From d692ea41394af9e073d4fe0c01c7988bbafbb9c1 Mon Sep 17 00:00:00 2001
From: Ghufran Zahidi <18732053+Ghufz@users.noreply.github.com>
Date: Mon, 12 Jun 2023 14:22:15 +0530
Subject: [PATCH 1/7] added property in HttpSIgningConfiguration to accept API
 key in string format.

---
 .../HttpSigningConfiguration.mustache         | 81 +++++++++++--------
 1 file changed, 49 insertions(+), 32 deletions(-)

diff --git a/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache b/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
index 6b773b8d596a..0ef145115c23 100644
--- a/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
@@ -40,6 +40,11 @@ namespace {{packageName}}.Client
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; } 
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -104,6 +109,17 @@ namespace {{packageName}}.Client
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -242,7 +258,7 @@ namespace {{packageName}}.Client
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -293,7 +309,7 @@ namespace {{packageName}}.Client
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -317,16 +333,7 @@ namespace {{packageName}}.Client
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -419,22 +426,13 @@ namespace {{packageName}}.Client
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -721,20 +719,15 @@ namespace {{packageName}}.Client
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -744,6 +737,7 @@ namespace {{packageName}}.Client
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -761,6 +755,29 @@ namespace {{packageName}}.Client
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }

From c384fe3b41285d678d1342d08d586977a2f8595e Mon Sep 17 00:00:00 2001
From: William Cheng <wing328hk@gmail.com>
Date: Mon, 12 Jun 2023 18:34:45 +0800
Subject: [PATCH 2/7] remove trailing space, update samples

---
 .../HttpSigningConfiguration.mustache         |  2 +-
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 9 files changed, 393 insertions(+), 257 deletions(-)

diff --git a/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache b/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
index 0ef145115c23..50d7bf35ab53 100644
--- a/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
@@ -43,7 +43,7 @@ namespace {{packageName}}.Client
         /// <summary>
         /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
         /// </summary>
-        public string KeyString { get; set; } 
+        public string KeyString { get; set; }
 
         /// <summary>
         /// Gets the key pass phrase for password protected key
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..116c890aee58 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; }
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..116c890aee58 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; }
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..116c890aee58 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; }
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..116c890aee58 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; }
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..116c890aee58 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; }
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..116c890aee58 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; }
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..116c890aee58 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; }
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..116c890aee58 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; }
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }

From 5b945c7a59ef03782dc5f48d97784894d6b41614 Mon Sep 17 00:00:00 2001
From: Ghufran Zahidi <18732053+Ghufz@users.noreply.github.com>
Date: Mon, 12 Jun 2023 16:14:43 +0530
Subject: [PATCH 3/7] updated the sample code.

---
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 .../Client/HttpSigningConfiguration.cs        | 81 +++++++++++--------
 8 files changed, 392 insertions(+), 256 deletions(-)

diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..265b513e84c2 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; } 
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..265b513e84c2 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; } 
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..265b513e84c2 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; } 
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..265b513e84c2 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; } 
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..265b513e84c2 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; } 
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..265b513e84c2 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; } 
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..265b513e84c2 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; } 
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 0b3e867d0f42..265b513e84c2 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,6 +48,11 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
+        /// <summary>
+        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
+        /// </summary>
+        public string KeyString { get; set; } 
+
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -112,6 +117,17 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
+            //Read the api key from the file
+            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            {
+                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
+            }
+
+            if(string.IsNullOrEmpty(KeyString))
+            {
+                throw new Exception("No API key has been provided.");
+            }
+
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -250,7 +266,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyFilePath);
+            var keyType = GetKeyType(KeyString);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -301,7 +317,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -325,16 +341,7 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            string keyStr = string.Empty;
-            if (File.Exists(KeyFilePath))
-            {
-                keyStr = File.ReadAllText(KeyFilePath);
-            }
-            else
-            {
-                keyStr = KeyFilePath;
-            }
-
+            var keyStr = KeyString;
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -427,22 +434,13 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-
-            string pemstr = string.Empty;
-            if (File.Exists(pemfile))
-            {
-                pemstr = File.ReadAllText(pemfile).Trim();
-            }
-            else
-            {
-                pemstr = pemfile;
-            }
+            string pemstr = keyString;
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -729,20 +727,15 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyFilePath">key file path in pem format</param>
+        /// <param name="keyString">api key in string format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyFilePath)
+        private PrivateKeyType GetKeyType(string keyString)
         {
             string[] key = null;
 
-            if (File.Exists(keyFilePath))
-            {
-                key = File.ReadAllLines(keyFilePath);
-            }
-            else
+            if (string.IsNullOrEmpty(keyString))
             {
-                // The ApiKeyFilePath is passed as string
-                key = new string[] { keyFilePath };
+                throw new Exception("No API key has been provided.");
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -752,6 +745,7 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
+            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -769,6 +763,29 @@ private PrivateKeyType GetKeyType(string keyFilePath)
             }
             return keyType;
         }
+
+        /// <summary>
+        /// Read the api key form the api key file path and stored it in KeyString property.
+        /// </summary>
+        /// <param name="apiKeyFilePath">api key file path</param>
+        private string ReadApiKeyFromFile(string apiKeyFilePath)
+        {
+            string apiKeyString = null;
+            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
+            {
+                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
+            }
+
+            if(File.Exists(apiKeyFilePath))
+            {
+                apiKeyString = File.ReadAllText(apiKeyFilePath);
+            }
+            else
+            {
+                throw new Exception("Provided API key file path does not exists.");
+            }
+            return apiKeyString;
+        }
         #endregion
     }
 }

From 811a62a0510ce9fc7390cb81b1d6ca63bd39132b Mon Sep 17 00:00:00 2001
From: Ghufran Zahidi <18732053+Ghufz@users.noreply.github.com>
Date: Tue, 13 Jun 2023 14:33:02 +0530
Subject: [PATCH 4/7] Revert "updated the sample code."

This reverts commit 5b945c7a59ef03782dc5f48d97784894d6b41614.
---
 .../Client/HttpSigningConfiguration.cs        | 81 ++++++++-----------
 .../Client/HttpSigningConfiguration.cs        | 81 ++++++++-----------
 .../Client/HttpSigningConfiguration.cs        | 81 ++++++++-----------
 .../Client/HttpSigningConfiguration.cs        | 81 ++++++++-----------
 .../Client/HttpSigningConfiguration.cs        | 81 ++++++++-----------
 .../Client/HttpSigningConfiguration.cs        | 81 ++++++++-----------
 .../Client/HttpSigningConfiguration.cs        | 81 ++++++++-----------
 .../Client/HttpSigningConfiguration.cs        | 81 ++++++++-----------
 8 files changed, 256 insertions(+), 392 deletions(-)

diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 265b513e84c2..0b3e867d0f42 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,11 +48,6 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
-        /// <summary>
-        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
-        /// </summary>
-        public string KeyString { get; set; } 
-
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -117,17 +112,6 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
-            //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
-            {
-                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
-            }
-
-            if(string.IsNullOrEmpty(KeyString))
-            {
-                throw new Exception("No API key has been provided.");
-            }
-
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -266,7 +250,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyString);
+            var keyType = GetKeyType(KeyFilePath);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -317,7 +301,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -341,7 +325,16 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            var keyStr = KeyString;
+            string keyStr = string.Empty;
+            if (File.Exists(KeyFilePath))
+            {
+                keyStr = File.ReadAllText(KeyFilePath);
+            }
+            else
+            {
+                keyStr = KeyFilePath;
+            }
+
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -434,13 +427,22 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-            string pemstr = keyString;
+
+            string pemstr = string.Empty;
+            if (File.Exists(pemfile))
+            {
+                pemstr = File.ReadAllText(pemfile).Trim();
+            }
+            else
+            {
+                pemstr = pemfile;
+            }
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -727,15 +729,20 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyString">api key in string format</param>
+        /// <param name="keyFilePath">key file path in pem format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyString)
+        private PrivateKeyType GetKeyType(string keyFilePath)
         {
             string[] key = null;
 
-            if (string.IsNullOrEmpty(keyString))
+            if (File.Exists(keyFilePath))
+            {
+                key = File.ReadAllLines(keyFilePath);
+            }
+            else
             {
-                throw new Exception("No API key has been provided.");
+                // The ApiKeyFilePath is passed as string
+                key = new string[] { keyFilePath };
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -745,7 +752,6 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -763,29 +769,6 @@ private PrivateKeyType GetKeyType(string keyString)
             }
             return keyType;
         }
-
-        /// <summary>
-        /// Read the api key form the api key file path and stored it in KeyString property.
-        /// </summary>
-        /// <param name="apiKeyFilePath">api key file path</param>
-        private string ReadApiKeyFromFile(string apiKeyFilePath)
-        {
-            string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
-            if(File.Exists(apiKeyFilePath))
-            {
-                apiKeyString = File.ReadAllText(apiKeyFilePath);
-            }
-            else
-            {
-                throw new Exception("Provided API key file path does not exists.");
-            }
-            return apiKeyString;
-        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 265b513e84c2..0b3e867d0f42 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,11 +48,6 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
-        /// <summary>
-        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
-        /// </summary>
-        public string KeyString { get; set; } 
-
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -117,17 +112,6 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
-            //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
-            {
-                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
-            }
-
-            if(string.IsNullOrEmpty(KeyString))
-            {
-                throw new Exception("No API key has been provided.");
-            }
-
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -266,7 +250,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyString);
+            var keyType = GetKeyType(KeyFilePath);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -317,7 +301,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -341,7 +325,16 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            var keyStr = KeyString;
+            string keyStr = string.Empty;
+            if (File.Exists(KeyFilePath))
+            {
+                keyStr = File.ReadAllText(KeyFilePath);
+            }
+            else
+            {
+                keyStr = KeyFilePath;
+            }
+
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -434,13 +427,22 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-            string pemstr = keyString;
+
+            string pemstr = string.Empty;
+            if (File.Exists(pemfile))
+            {
+                pemstr = File.ReadAllText(pemfile).Trim();
+            }
+            else
+            {
+                pemstr = pemfile;
+            }
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -727,15 +729,20 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyString">api key in string format</param>
+        /// <param name="keyFilePath">key file path in pem format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyString)
+        private PrivateKeyType GetKeyType(string keyFilePath)
         {
             string[] key = null;
 
-            if (string.IsNullOrEmpty(keyString))
+            if (File.Exists(keyFilePath))
+            {
+                key = File.ReadAllLines(keyFilePath);
+            }
+            else
             {
-                throw new Exception("No API key has been provided.");
+                // The ApiKeyFilePath is passed as string
+                key = new string[] { keyFilePath };
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -745,7 +752,6 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -763,29 +769,6 @@ private PrivateKeyType GetKeyType(string keyString)
             }
             return keyType;
         }
-
-        /// <summary>
-        /// Read the api key form the api key file path and stored it in KeyString property.
-        /// </summary>
-        /// <param name="apiKeyFilePath">api key file path</param>
-        private string ReadApiKeyFromFile(string apiKeyFilePath)
-        {
-            string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
-            if(File.Exists(apiKeyFilePath))
-            {
-                apiKeyString = File.ReadAllText(apiKeyFilePath);
-            }
-            else
-            {
-                throw new Exception("Provided API key file path does not exists.");
-            }
-            return apiKeyString;
-        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 265b513e84c2..0b3e867d0f42 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,11 +48,6 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
-        /// <summary>
-        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
-        /// </summary>
-        public string KeyString { get; set; } 
-
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -117,17 +112,6 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
-            //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
-            {
-                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
-            }
-
-            if(string.IsNullOrEmpty(KeyString))
-            {
-                throw new Exception("No API key has been provided.");
-            }
-
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -266,7 +250,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyString);
+            var keyType = GetKeyType(KeyFilePath);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -317,7 +301,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -341,7 +325,16 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            var keyStr = KeyString;
+            string keyStr = string.Empty;
+            if (File.Exists(KeyFilePath))
+            {
+                keyStr = File.ReadAllText(KeyFilePath);
+            }
+            else
+            {
+                keyStr = KeyFilePath;
+            }
+
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -434,13 +427,22 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-            string pemstr = keyString;
+
+            string pemstr = string.Empty;
+            if (File.Exists(pemfile))
+            {
+                pemstr = File.ReadAllText(pemfile).Trim();
+            }
+            else
+            {
+                pemstr = pemfile;
+            }
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -727,15 +729,20 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyString">api key in string format</param>
+        /// <param name="keyFilePath">key file path in pem format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyString)
+        private PrivateKeyType GetKeyType(string keyFilePath)
         {
             string[] key = null;
 
-            if (string.IsNullOrEmpty(keyString))
+            if (File.Exists(keyFilePath))
+            {
+                key = File.ReadAllLines(keyFilePath);
+            }
+            else
             {
-                throw new Exception("No API key has been provided.");
+                // The ApiKeyFilePath is passed as string
+                key = new string[] { keyFilePath };
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -745,7 +752,6 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -763,29 +769,6 @@ private PrivateKeyType GetKeyType(string keyString)
             }
             return keyType;
         }
-
-        /// <summary>
-        /// Read the api key form the api key file path and stored it in KeyString property.
-        /// </summary>
-        /// <param name="apiKeyFilePath">api key file path</param>
-        private string ReadApiKeyFromFile(string apiKeyFilePath)
-        {
-            string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
-            if(File.Exists(apiKeyFilePath))
-            {
-                apiKeyString = File.ReadAllText(apiKeyFilePath);
-            }
-            else
-            {
-                throw new Exception("Provided API key file path does not exists.");
-            }
-            return apiKeyString;
-        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 265b513e84c2..0b3e867d0f42 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,11 +48,6 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
-        /// <summary>
-        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
-        /// </summary>
-        public string KeyString { get; set; } 
-
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -117,17 +112,6 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
-            //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
-            {
-                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
-            }
-
-            if(string.IsNullOrEmpty(KeyString))
-            {
-                throw new Exception("No API key has been provided.");
-            }
-
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -266,7 +250,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyString);
+            var keyType = GetKeyType(KeyFilePath);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -317,7 +301,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -341,7 +325,16 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            var keyStr = KeyString;
+            string keyStr = string.Empty;
+            if (File.Exists(KeyFilePath))
+            {
+                keyStr = File.ReadAllText(KeyFilePath);
+            }
+            else
+            {
+                keyStr = KeyFilePath;
+            }
+
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -434,13 +427,22 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-            string pemstr = keyString;
+
+            string pemstr = string.Empty;
+            if (File.Exists(pemfile))
+            {
+                pemstr = File.ReadAllText(pemfile).Trim();
+            }
+            else
+            {
+                pemstr = pemfile;
+            }
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -727,15 +729,20 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyString">api key in string format</param>
+        /// <param name="keyFilePath">key file path in pem format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyString)
+        private PrivateKeyType GetKeyType(string keyFilePath)
         {
             string[] key = null;
 
-            if (string.IsNullOrEmpty(keyString))
+            if (File.Exists(keyFilePath))
+            {
+                key = File.ReadAllLines(keyFilePath);
+            }
+            else
             {
-                throw new Exception("No API key has been provided.");
+                // The ApiKeyFilePath is passed as string
+                key = new string[] { keyFilePath };
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -745,7 +752,6 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -763,29 +769,6 @@ private PrivateKeyType GetKeyType(string keyString)
             }
             return keyType;
         }
-
-        /// <summary>
-        /// Read the api key form the api key file path and stored it in KeyString property.
-        /// </summary>
-        /// <param name="apiKeyFilePath">api key file path</param>
-        private string ReadApiKeyFromFile(string apiKeyFilePath)
-        {
-            string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
-            if(File.Exists(apiKeyFilePath))
-            {
-                apiKeyString = File.ReadAllText(apiKeyFilePath);
-            }
-            else
-            {
-                throw new Exception("Provided API key file path does not exists.");
-            }
-            return apiKeyString;
-        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 265b513e84c2..0b3e867d0f42 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,11 +48,6 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
-        /// <summary>
-        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
-        /// </summary>
-        public string KeyString { get; set; } 
-
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -117,17 +112,6 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
-            //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
-            {
-                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
-            }
-
-            if(string.IsNullOrEmpty(KeyString))
-            {
-                throw new Exception("No API key has been provided.");
-            }
-
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -266,7 +250,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyString);
+            var keyType = GetKeyType(KeyFilePath);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -317,7 +301,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -341,7 +325,16 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            var keyStr = KeyString;
+            string keyStr = string.Empty;
+            if (File.Exists(KeyFilePath))
+            {
+                keyStr = File.ReadAllText(KeyFilePath);
+            }
+            else
+            {
+                keyStr = KeyFilePath;
+            }
+
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -434,13 +427,22 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-            string pemstr = keyString;
+
+            string pemstr = string.Empty;
+            if (File.Exists(pemfile))
+            {
+                pemstr = File.ReadAllText(pemfile).Trim();
+            }
+            else
+            {
+                pemstr = pemfile;
+            }
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -727,15 +729,20 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyString">api key in string format</param>
+        /// <param name="keyFilePath">key file path in pem format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyString)
+        private PrivateKeyType GetKeyType(string keyFilePath)
         {
             string[] key = null;
 
-            if (string.IsNullOrEmpty(keyString))
+            if (File.Exists(keyFilePath))
+            {
+                key = File.ReadAllLines(keyFilePath);
+            }
+            else
             {
-                throw new Exception("No API key has been provided.");
+                // The ApiKeyFilePath is passed as string
+                key = new string[] { keyFilePath };
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -745,7 +752,6 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -763,29 +769,6 @@ private PrivateKeyType GetKeyType(string keyString)
             }
             return keyType;
         }
-
-        /// <summary>
-        /// Read the api key form the api key file path and stored it in KeyString property.
-        /// </summary>
-        /// <param name="apiKeyFilePath">api key file path</param>
-        private string ReadApiKeyFromFile(string apiKeyFilePath)
-        {
-            string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
-            if(File.Exists(apiKeyFilePath))
-            {
-                apiKeyString = File.ReadAllText(apiKeyFilePath);
-            }
-            else
-            {
-                throw new Exception("Provided API key file path does not exists.");
-            }
-            return apiKeyString;
-        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 265b513e84c2..0b3e867d0f42 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,11 +48,6 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
-        /// <summary>
-        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
-        /// </summary>
-        public string KeyString { get; set; } 
-
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -117,17 +112,6 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
-            //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
-            {
-                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
-            }
-
-            if(string.IsNullOrEmpty(KeyString))
-            {
-                throw new Exception("No API key has been provided.");
-            }
-
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -266,7 +250,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyString);
+            var keyType = GetKeyType(KeyFilePath);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -317,7 +301,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -341,7 +325,16 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            var keyStr = KeyString;
+            string keyStr = string.Empty;
+            if (File.Exists(KeyFilePath))
+            {
+                keyStr = File.ReadAllText(KeyFilePath);
+            }
+            else
+            {
+                keyStr = KeyFilePath;
+            }
+
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -434,13 +427,22 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-            string pemstr = keyString;
+
+            string pemstr = string.Empty;
+            if (File.Exists(pemfile))
+            {
+                pemstr = File.ReadAllText(pemfile).Trim();
+            }
+            else
+            {
+                pemstr = pemfile;
+            }
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -727,15 +729,20 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyString">api key in string format</param>
+        /// <param name="keyFilePath">key file path in pem format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyString)
+        private PrivateKeyType GetKeyType(string keyFilePath)
         {
             string[] key = null;
 
-            if (string.IsNullOrEmpty(keyString))
+            if (File.Exists(keyFilePath))
+            {
+                key = File.ReadAllLines(keyFilePath);
+            }
+            else
             {
-                throw new Exception("No API key has been provided.");
+                // The ApiKeyFilePath is passed as string
+                key = new string[] { keyFilePath };
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -745,7 +752,6 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -763,29 +769,6 @@ private PrivateKeyType GetKeyType(string keyString)
             }
             return keyType;
         }
-
-        /// <summary>
-        /// Read the api key form the api key file path and stored it in KeyString property.
-        /// </summary>
-        /// <param name="apiKeyFilePath">api key file path</param>
-        private string ReadApiKeyFromFile(string apiKeyFilePath)
-        {
-            string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
-            if(File.Exists(apiKeyFilePath))
-            {
-                apiKeyString = File.ReadAllText(apiKeyFilePath);
-            }
-            else
-            {
-                throw new Exception("Provided API key file path does not exists.");
-            }
-            return apiKeyString;
-        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 265b513e84c2..0b3e867d0f42 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,11 +48,6 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
-        /// <summary>
-        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
-        /// </summary>
-        public string KeyString { get; set; } 
-
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -117,17 +112,6 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
-            //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
-            {
-                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
-            }
-
-            if(string.IsNullOrEmpty(KeyString))
-            {
-                throw new Exception("No API key has been provided.");
-            }
-
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -266,7 +250,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyString);
+            var keyType = GetKeyType(KeyFilePath);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -317,7 +301,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -341,7 +325,16 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            var keyStr = KeyString;
+            string keyStr = string.Empty;
+            if (File.Exists(KeyFilePath))
+            {
+                keyStr = File.ReadAllText(KeyFilePath);
+            }
+            else
+            {
+                keyStr = KeyFilePath;
+            }
+
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -434,13 +427,22 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-            string pemstr = keyString;
+
+            string pemstr = string.Empty;
+            if (File.Exists(pemfile))
+            {
+                pemstr = File.ReadAllText(pemfile).Trim();
+            }
+            else
+            {
+                pemstr = pemfile;
+            }
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -727,15 +729,20 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyString">api key in string format</param>
+        /// <param name="keyFilePath">key file path in pem format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyString)
+        private PrivateKeyType GetKeyType(string keyFilePath)
         {
             string[] key = null;
 
-            if (string.IsNullOrEmpty(keyString))
+            if (File.Exists(keyFilePath))
+            {
+                key = File.ReadAllLines(keyFilePath);
+            }
+            else
             {
-                throw new Exception("No API key has been provided.");
+                // The ApiKeyFilePath is passed as string
+                key = new string[] { keyFilePath };
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -745,7 +752,6 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -763,29 +769,6 @@ private PrivateKeyType GetKeyType(string keyString)
             }
             return keyType;
         }
-
-        /// <summary>
-        /// Read the api key form the api key file path and stored it in KeyString property.
-        /// </summary>
-        /// <param name="apiKeyFilePath">api key file path</param>
-        private string ReadApiKeyFromFile(string apiKeyFilePath)
-        {
-            string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
-            if(File.Exists(apiKeyFilePath))
-            {
-                apiKeyString = File.ReadAllText(apiKeyFilePath);
-            }
-            else
-            {
-                throw new Exception("Provided API key file path does not exists.");
-            }
-            return apiKeyString;
-        }
         #endregion
     }
 }
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 265b513e84c2..0b3e867d0f42 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -48,11 +48,6 @@ public HttpSigningConfiguration()
         /// </summary>
         public string KeyFilePath { get; set; }
 
-        /// <summary>
-        /// Specify the API key in the form of a string, either configure the KeyString property or configure the KeyFilePath property.
-        /// </summary>
-        public string KeyString { get; set; } 
-
         /// <summary>
         /// Gets the key pass phrase for password protected key
         /// </summary>
@@ -117,17 +112,6 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             //the list of signed headers and a base64-encoded signature.
             const string HEADER_AUTHORIZATION = "Authorization";
 
-            //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
-            {
-                this.KeyString = ReadApiKeyFromFile(KeyFilePath);
-            }
-
-            if(string.IsNullOrEmpty(KeyString))
-            {
-                throw new Exception("No API key has been provided.");
-            }
-
             //Hash table to store singed headers
             var HttpSignedRequestHeader = new Dictionary<string, string>();
             var HttpSignatureHeader = new Dictionary<string, string>();
@@ -266,7 +250,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             var headerValuesString = string.Join("\n", headerValuesList);
             var signatureStringHash = GetStringHash(HashAlgorithm.ToString(), headerValuesString);
             string headerSignatureStr = null;
-            var keyType = GetKeyType(KeyString);
+            var keyType = GetKeyType(KeyFilePath);
 
             if (keyType == PrivateKeyType.RSA)
             {
@@ -317,7 +301,7 @@ private int GetUnixTime(DateTime date2)
 
         private string GetRSASignature(byte[] stringToSign)
         {
-            RSA rsa = GetRSAProviderFromPemFile(KeyString, KeyPassPhrase);
+            RSA rsa = GetRSAProviderFromPemFile(KeyFilePath, KeyPassPhrase);
             if (SigningAlgorithm == "RSASSA-PSS")
             {
                 var signedbytes = rsa.SignHash(stringToSign, HashAlgorithm, RSASignaturePadding.Pss);
@@ -341,7 +325,16 @@ private string GetRSASignature(byte[] stringToSign)
         /// <returns>ECDSA signature</returns>
         private string GetECDSASignature(byte[] dataToSign)
         {
-            var keyStr = KeyString;
+            string keyStr = string.Empty;
+            if (File.Exists(KeyFilePath))
+            {
+                keyStr = File.ReadAllText(KeyFilePath);
+            }
+            else
+            {
+                keyStr = KeyFilePath;
+            }
+
             const string ecKeyHeader = "-----BEGIN EC PRIVATE KEY-----";
             const string ecKeyFooter = "-----END EC PRIVATE KEY-----";
             var ecKeyBase64String = keyStr.Replace(ecKeyHeader, "").Replace(ecKeyFooter, "").Trim();
@@ -434,13 +427,22 @@ private byte[] ConvertToECDSAANS1Format(byte[] signedBytes)
             return derBytes.ToArray();
         }
 
-        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string keyString, SecureString keyPassPhrase = null)
+        private  RSACryptoServiceProvider GetRSAProviderFromPemFile(string pemfile, SecureString keyPassPhrase = null)
         {
             const string pempubheader = "-----BEGIN PUBLIC KEY-----";
             const string pempubfooter = "-----END PUBLIC KEY-----";
             bool isPrivateKeyFile = true;
             byte[] pemkey = null;
-            string pemstr = keyString;
+
+            string pemstr = string.Empty;
+            if (File.Exists(pemfile))
+            {
+                pemstr = File.ReadAllText(pemfile).Trim();
+            }
+            else
+            {
+                pemstr = pemfile;
+            }
 
             if (pemstr.StartsWith(pempubheader) && pemstr.EndsWith(pempubfooter))
             {
@@ -727,15 +729,20 @@ private byte[] DecryptKey(byte[] cipherData, byte[] desKey, byte[] IV)
         /// <summary>
         /// Detect the key type from the pem file.
         /// </summary>
-        /// <param name="keyString">api key in string format</param>
+        /// <param name="keyFilePath">key file path in pem format</param>
         /// <returns>Private Key Type</returns>
-        private PrivateKeyType GetKeyType(string keyString)
+        private PrivateKeyType GetKeyType(string keyFilePath)
         {
             string[] key = null;
 
-            if (string.IsNullOrEmpty(keyString))
+            if (File.Exists(keyFilePath))
+            {
+                key = File.ReadAllLines(keyFilePath);
+            }
+            else
             {
-                throw new Exception("No API key has been provided.");
+                // The ApiKeyFilePath is passed as string
+                key = new string[] { keyFilePath };
             }
 
             const string ecPrivateKeyHeader = "BEGIN EC PRIVATE KEY";
@@ -745,7 +752,6 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
@@ -763,29 +769,6 @@ private PrivateKeyType GetKeyType(string keyString)
             }
             return keyType;
         }
-
-        /// <summary>
-        /// Read the api key form the api key file path and stored it in KeyString property.
-        /// </summary>
-        /// <param name="apiKeyFilePath">api key file path</param>
-        private string ReadApiKeyFromFile(string apiKeyFilePath)
-        {
-            string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
-            if(File.Exists(apiKeyFilePath))
-            {
-                apiKeyString = File.ReadAllText(apiKeyFilePath);
-            }
-            else
-            {
-                throw new Exception("Provided API key file path does not exists.");
-            }
-            return apiKeyString;
-        }
         #endregion
     }
 }

From ec6404d511d20b2847dfd974232c2c68eab24daa Mon Sep 17 00:00:00 2001
From: Ghufran Zahidi <18732053+Ghufz@users.noreply.github.com>
Date: Tue, 13 Jun 2023 14:36:25 +0530
Subject: [PATCH 5/7] fix the sample code compilation error for split function.

---
 .../resources/csharp-netcore/HttpSigningConfiguration.mustache  | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache b/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
index 50d7bf35ab53..983ab4883404 100644
--- a/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
@@ -737,7 +737,7 @@ namespace {{packageName}}.Client
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
+            key = KeyString.TrimEnd().Split('\n');
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))

From 368a2e4ba3a8fe634254ee63f8f368d3b71da713 Mon Sep 17 00:00:00 2001
From: Ghufran Zahidi <18732053+Ghufz@users.noreply.github.com>
Date: Tue, 13 Jun 2023 14:41:05 +0530
Subject: [PATCH 6/7] updated the sample code after the split function fix.

---
 .../src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs     | 2 +-
 .../src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs     | 2 +-
 .../src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs     | 2 +-
 .../src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs     | 2 +-
 .../src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs     | 2 +-
 .../src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs     | 2 +-
 .../src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs     | 2 +-
 .../src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs     | 2 +-
 8 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 116c890aee58..790be8d020f0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -745,7 +745,7 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
+            key = KeyString.TrimEnd().Split('\n');
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 116c890aee58..790be8d020f0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -745,7 +745,7 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
+            key = KeyString.TrimEnd().Split('\n');
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 116c890aee58..790be8d020f0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -745,7 +745,7 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
+            key = KeyString.TrimEnd().Split('\n');
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 116c890aee58..790be8d020f0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -745,7 +745,7 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
+            key = KeyString.TrimEnd().Split('\n');
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 116c890aee58..790be8d020f0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -745,7 +745,7 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
+            key = KeyString.TrimEnd().Split('\n');
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 116c890aee58..790be8d020f0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -745,7 +745,7 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
+            key = KeyString.TrimEnd().Split('\n');
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 116c890aee58..790be8d020f0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -745,7 +745,7 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
+            key = KeyString.TrimEnd().Split('\n');
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 116c890aee58..790be8d020f0 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -745,7 +745,7 @@ private PrivateKeyType GetKeyType(string keyString)
             //var pkcs8Header = "BEGIN PRIVATE KEY";
             //var pkcs8Footer = "END PRIVATE KEY";
             PrivateKeyType keyType;
-            key = KeyString.TrimEnd().Split("\n");
+            key = KeyString.TrimEnd().Split('\n');
 
             if (key[0].Contains(rsaPrivateKeyHeader) &&
                 key[key.Length - 1].ToString().Contains(rsaPrivateFooter))

From a9a585649722b444baabf3e59985639939a8080f Mon Sep 17 00:00:00 2001
From: Ghufran Zahidi <18732053+Ghufz@users.noreply.github.com>
Date: Tue, 13 Jun 2023 17:56:26 +0530
Subject: [PATCH 7/7] Removed the either or check for filePath or KeyString.

---
 .../csharp-netcore/HttpSigningConfiguration.mustache      | 8 ++------
 .../Org.OpenAPITools/Client/HttpSigningConfiguration.cs   | 8 ++------
 .../Org.OpenAPITools/Client/HttpSigningConfiguration.cs   | 8 ++------
 .../Org.OpenAPITools/Client/HttpSigningConfiguration.cs   | 8 ++------
 .../Org.OpenAPITools/Client/HttpSigningConfiguration.cs   | 8 ++------
 .../Org.OpenAPITools/Client/HttpSigningConfiguration.cs   | 8 ++------
 .../Org.OpenAPITools/Client/HttpSigningConfiguration.cs   | 8 ++------
 .../Org.OpenAPITools/Client/HttpSigningConfiguration.cs   | 8 ++------
 .../Org.OpenAPITools/Client/HttpSigningConfiguration.cs   | 8 ++------
 9 files changed, 18 insertions(+), 54 deletions(-)

diff --git a/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache b/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
index 983ab4883404..a1169150ea22 100644
--- a/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp-netcore/HttpSigningConfiguration.mustache
@@ -110,7 +110,7 @@ namespace {{packageName}}.Client
             const string HEADER_AUTHORIZATION = "Authorization";
 
             //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            if(string.IsNullOrEmpty(this.KeyString))
             {
                 this.KeyString = ReadApiKeyFromFile(KeyFilePath);
             }
@@ -763,11 +763,7 @@ namespace {{packageName}}.Client
         private string ReadApiKeyFromFile(string apiKeyFilePath)
         {
             string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
+            
             if(File.Exists(apiKeyFilePath))
             {
                 apiKeyString = File.ReadAllText(apiKeyFilePath);
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 790be8d020f0..05442e501a96 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-ConditionalSerialization/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -118,7 +118,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             const string HEADER_AUTHORIZATION = "Authorization";
 
             //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            if(string.IsNullOrEmpty(this.KeyString))
             {
                 this.KeyString = ReadApiKeyFromFile(KeyFilePath);
             }
@@ -771,11 +771,7 @@ private PrivateKeyType GetKeyType(string keyString)
         private string ReadApiKeyFromFile(string apiKeyFilePath)
         {
             string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
+            
             if(File.Exists(apiKeyFilePath))
             {
                 apiKeyString = File.ReadAllText(apiKeyFilePath);
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 790be8d020f0..05442e501a96 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-httpclient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -118,7 +118,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             const string HEADER_AUTHORIZATION = "Authorization";
 
             //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            if(string.IsNullOrEmpty(this.KeyString))
             {
                 this.KeyString = ReadApiKeyFromFile(KeyFilePath);
             }
@@ -771,11 +771,7 @@ private PrivateKeyType GetKeyType(string keyString)
         private string ReadApiKeyFromFile(string apiKeyFilePath)
         {
             string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
+            
             if(File.Exists(apiKeyFilePath))
             {
                 apiKeyString = File.ReadAllText(apiKeyFilePath);
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 790be8d020f0..05442e501a96 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net47/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -118,7 +118,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             const string HEADER_AUTHORIZATION = "Authorization";
 
             //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            if(string.IsNullOrEmpty(this.KeyString))
             {
                 this.KeyString = ReadApiKeyFromFile(KeyFilePath);
             }
@@ -771,11 +771,7 @@ private PrivateKeyType GetKeyType(string keyString)
         private string ReadApiKeyFromFile(string apiKeyFilePath)
         {
             string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
+            
             if(File.Exists(apiKeyFilePath))
             {
                 apiKeyString = File.ReadAllText(apiKeyFilePath);
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 790be8d020f0..05442e501a96 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net48/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -118,7 +118,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             const string HEADER_AUTHORIZATION = "Authorization";
 
             //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            if(string.IsNullOrEmpty(this.KeyString))
             {
                 this.KeyString = ReadApiKeyFromFile(KeyFilePath);
             }
@@ -771,11 +771,7 @@ private PrivateKeyType GetKeyType(string keyString)
         private string ReadApiKeyFromFile(string apiKeyFilePath)
         {
             string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
+            
             if(File.Exists(apiKeyFilePath))
             {
                 apiKeyString = File.ReadAllText(apiKeyFilePath);
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 790be8d020f0..05442e501a96 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-net5.0/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -118,7 +118,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             const string HEADER_AUTHORIZATION = "Authorization";
 
             //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            if(string.IsNullOrEmpty(this.KeyString))
             {
                 this.KeyString = ReadApiKeyFromFile(KeyFilePath);
             }
@@ -771,11 +771,7 @@ private PrivateKeyType GetKeyType(string keyString)
         private string ReadApiKeyFromFile(string apiKeyFilePath)
         {
             string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
+            
             if(File.Exists(apiKeyFilePath))
             {
                 apiKeyString = File.ReadAllText(apiKeyFilePath);
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 790be8d020f0..05442e501a96 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient-unityWebRequest/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -118,7 +118,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             const string HEADER_AUTHORIZATION = "Authorization";
 
             //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            if(string.IsNullOrEmpty(this.KeyString))
             {
                 this.KeyString = ReadApiKeyFromFile(KeyFilePath);
             }
@@ -771,11 +771,7 @@ private PrivateKeyType GetKeyType(string keyString)
         private string ReadApiKeyFromFile(string apiKeyFilePath)
         {
             string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
+            
             if(File.Exists(apiKeyFilePath))
             {
                 apiKeyString = File.ReadAllText(apiKeyFilePath);
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 790be8d020f0..05442e501a96 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -118,7 +118,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             const string HEADER_AUTHORIZATION = "Authorization";
 
             //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            if(string.IsNullOrEmpty(this.KeyString))
             {
                 this.KeyString = ReadApiKeyFromFile(KeyFilePath);
             }
@@ -771,11 +771,7 @@ private PrivateKeyType GetKeyType(string keyString)
         private string ReadApiKeyFromFile(string apiKeyFilePath)
         {
             string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
+            
             if(File.Exists(apiKeyFilePath))
             {
                 apiKeyString = File.ReadAllText(apiKeyFilePath);
diff --git a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
index 790be8d020f0..05442e501a96 100644
--- a/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
+++ b/samples/client/petstore/csharp-netcore/OpenAPIClientCore/src/Org.OpenAPITools/Client/HttpSigningConfiguration.cs
@@ -118,7 +118,7 @@ internal Dictionary<string, string> GetHttpSignedHeader(string basePath,string m
             const string HEADER_AUTHORIZATION = "Authorization";
 
             //Read the api key from the file
-            if(!string.IsNullOrEmpty(this.KeyFilePath))
+            if(string.IsNullOrEmpty(this.KeyString))
             {
                 this.KeyString = ReadApiKeyFromFile(KeyFilePath);
             }
@@ -771,11 +771,7 @@ private PrivateKeyType GetKeyType(string keyString)
         private string ReadApiKeyFromFile(string apiKeyFilePath)
         {
             string apiKeyString = null;
-            if(!string.IsNullOrEmpty(apiKeyFilePath) && !string.IsNullOrEmpty(this.KeyString))
-            {
-                throw new Exception("Configure either the KeyFilePath or configure the KeyString property.");
-            }
-
+            
             if(File.Exists(apiKeyFilePath))
             {
                 apiKeyString = File.ReadAllText(apiKeyFilePath);