Add MinimumDeploymentFee (#2140)

Author: erikzhang

src/neo/SmartContract/Native/ManagementContract.cs

@@ -17,6 +17,7 @@ public sealed class ManagementContract : NativeContract
         public override int Id => 0;
         public override uint ActiveBlockIndex => 0;
 
+        private const byte Prefix_MinimumDeploymentFee = 20;
         private const byte Prefix_NextAvailableId = 15;
         private const byte Prefix_Contract = 8;
 
@@ -28,6 +29,11 @@ private int GetNextAvailableId(StoreView snapshot)
             return value;
         }
 
+        internal override void Initialize(ApplicationEngine engine)
+        {
+            engine.Snapshot.Storages.Add(CreateStorageKey(Prefix_MinimumDeploymentFee), new StorageItem(100_00000000));
+        }
+
         internal override void OnPersist(ApplicationEngine engine)
         {
             foreach (NativeContract contract in Contracts)
@@ -45,6 +51,20 @@ internal override void OnPersist(ApplicationEngine engine)
             }
         }
 
+        [ContractMethod(0_01000000, CallFlags.ReadStates)]
+        private long GetMinimumDeploymentFee(StoreView snapshot)
+        {
+            return (long)(BigInteger)snapshot.Storages[CreateStorageKey(Prefix_MinimumDeploymentFee)];
+        }
+
+        [ContractMethod(0_03000000, CallFlags.WriteStates)]
+        private void SetMinimumDeploymentFee(ApplicationEngine engine, BigInteger value)
+        {
+            if (value < 0) throw new ArgumentOutOfRangeException(nameof(value));
+            if (!CheckCommittee(engine)) throw new InvalidOperationException();
+            engine.Snapshot.Storages.GetAndChange(CreateStorageKey(Prefix_MinimumDeploymentFee)).Set(value);
+        }
+
         [ContractMethod(0_01000000, CallFlags.ReadStates)]
         public ContractState GetContract(StoreView snapshot, UInt160 hash)
         {
@@ -67,7 +87,10 @@ private ContractState Deploy(ApplicationEngine engine, byte[] nefFile, byte[] ma
             if (manifest.Length == 0 || manifest.Length > ContractManifest.MaxLength)
                 throw new ArgumentException($"Invalid Manifest Length: {manifest.Length}");
 
-            engine.AddGas(engine.StoragePrice * (nefFile.Length + manifest.Length));
+            engine.AddGas(Math.Max(
+                engine.StoragePrice * (nefFile.Length + manifest.Length),
+                GetMinimumDeploymentFee(engine.Snapshot)
+                ));
 
             NefFile nef = nefFile.AsSerializable<NefFile>();
             UInt160 hash = Helper.GetContractHash(tx.Sender, nef.Script);

tests/neo.UnitTests/Extensions/NativeContractExtensions.cs

@@ -10,7 +10,7 @@ namespace Neo.UnitTests.Extensions
 {
     public static class NativeContractExtensions
     {
-        public static ContractState DeployContract(this StoreView snapshot, UInt160 sender, byte[] nefFile, byte[] manifest, long gas = ApplicationEngine.TestModeGas)
+        public static ContractState DeployContract(this StoreView snapshot, UInt160 sender, byte[] nefFile, byte[] manifest, long gas = 200_00000000)
         {
             var script = new ScriptBuilder();
             script.EmitAppCall(NativeContract.Management.Hash, "deploy", nefFile, manifest);