refactor: Add validation for serverApi version and tests

Author: dariakp

src/connection_string.ts

@@ -23,7 +23,8 @@ import {
   MongoClientOptions,
   MongoOptions,
   PkFactory,
-  ServerApi
+  ServerApi,
+  ServerApiVersion
 } from './mongo_client';
 import { MongoCredentials } from './cmap/auth/mongo_credentials';
 import type { TagSet } from './sdam/server_description';
@@ -590,10 +591,24 @@ export const OPTIONS = {
   serverApi: {
     target: 'serverApi',
     transform({ values: [version] }): ServerApi {
-      if (typeof version === 'string') {
-        return { version };
+      const serverApiToValidate =
+        typeof version === 'string' ? ({ version } as ServerApi) : (version as ServerApi);
+      const versionToValidate = serverApiToValidate && serverApiToValidate.version;
+      if (!versionToValidate) {
+        throw new MongoParseError(
+          `Invalid \`serverApi\` property; must specify a version as one of the following strings: "${Object.values(
+            ServerApiVersion
+          ).join('", "')}"`
+        );
+      }
+      if (!Object.values(ServerApiVersion).some(v => v === versionToValidate)) {
+        throw new MongoParseError(
+          `Invalid server API version=${versionToValidate}; must be one of the following strings: "${Object.values(
+            ServerApiVersion
+          ).join('", "')}"`
+        );
       }
-      return version as ServerApi;
+      return serverApiToValidate;
     }
   },
   checkKeys: {

src/mongo_client.ts

@@ -43,7 +43,7 @@ export type ServerApiVersion = typeof ServerApiVersion[keyof typeof ServerApiVer
 
 /** @public */
 export interface ServerApi {
-  version: string | ServerApiVersion;
+  version: ServerApiVersion;
   strict?: boolean;
   deprecationErrors?: boolean;
 }

test/unit/mongo_client_options.test.js

@@ -8,7 +8,7 @@ const { WriteConcern } = require('../../src/write_concern');
 const { ReadPreference } = require('../../src/read_preference');
 const { Logger } = require('../../src/logger');
 const { MongoCredentials } = require('../../src/cmap/auth/mongo_credentials');
-const { MongoClient, MongoParseError } = require('../../src');
+const { MongoClient, MongoParseError, ServerApiVersion } = require('../../src');
 
 describe('MongoOptions', function () {
   it('MongoClient should always freeze public options', function () {
@@ -122,6 +122,7 @@ describe('MongoOptions', function () {
     serializeFunctions: true,
     serverSelectionTimeoutMS: 3,
     servername: 'some tls option',
+    serverApi: { version: '1' },
     socketTimeoutMS: 3,
     ssl: true,
     sslPass: 'pass',
@@ -369,4 +370,71 @@ describe('MongoOptions', function () {
     expect(optionsUndefined.rejectUnauthorized).to.equal(undefined);
     expect(optionsUndefined.checkServerIdentity).to.equal(undefined);
   });
+
+  describe('serverApi', function () {
+    it('is supported as a client option when it is a valid ServerApiVersion string', function () {
+      const validVersions = Object.values(ServerApiVersion);
+      expect(validVersions.length).to.be.at.least(1);
+      for (const version of validVersions) {
+        const result = parseOptions('mongodb://localhost/', {
+          serverApi: version
+        });
+        expect(result).to.have.property('serverApi').deep.equal({ version });
+      }
+    });
+
+    it('is supported as a client option when it is an object with a valid version property', function () {
+      const validVersions = Object.values(ServerApiVersion);
+      expect(validVersions.length).to.be.at.least(1);
+      for (const version of validVersions) {
+        const result = parseOptions('mongodb://localhost/', {
+          serverApi: { version }
+        });
+        expect(result).to.have.property('serverApi').deep.equal({ version });
+      }
+    });
+
+    it('is not supported as a client option when it is an invalid string', function () {
+      expect(() =>
+        parseOptions('mongodb://localhost/', {
+          serverApi: 'bad'
+        })
+      ).to.throw(/^Invalid server API version=bad;/);
+    });
+
+    it('is not supported as a client option when it is a number', function () {
+      expect(() =>
+        parseOptions('mongodb://localhost/', {
+          serverApi: 1
+        })
+      ).to.throw(/^Invalid `serverApi` property;/);
+    });
+
+    it('is not supported as a client option when it is an object without a specified version', function () {
+      expect(() =>
+        parseOptions('mongodb://localhost/', {
+          serverApi: {}
+        })
+      ).to.throw(/^Invalid `serverApi` property;/);
+    });
+
+    it('is not supported as a client option when it is an object with an invalid specified version', function () {
+      expect(() =>
+        parseOptions('mongodb://localhost/', {
+          serverApi: { version: 1 }
+        })
+      ).to.throw(/^Invalid server API version=1;/);
+      expect(() =>
+        parseOptions('mongodb://localhost/', {
+          serverApi: { version: 'bad' }
+        })
+      ).to.throw(/^Invalid server API version=bad;/);
+    });
+
+    it('is not supported as a URI option even when it is a valid ServerApiVersion string', function () {
+      expect(() => parseOptions('mongodb://localhost/?serverApi=1')).to.throw(
+        'URI cannot contain `serverApi`, it can only be passed to the client'
+      );
+    });
+  });
 });