fix(NODE-3591): tlsCertificateKeyFile option does not default cert

src/connection_string.ts

@@ -176,7 +176,7 @@ function getBoolean(name: string, value: unknown): boolean {
   const valueString = String(value).toLowerCase();
   if (TRUTHS.has(valueString)) return true;
   if (FALSEHOODS.has(valueString)) return false;
-  throw new MongoParseError(`For ${name} Expected stringified boolean value, got: ${value}`);
+  throw new MongoParseError(`Expected ${name} to be stringified boolean value, got: ${value}`);
 }
 
 function getInt(name: string, value: unknown): number {
@@ -335,6 +335,19 @@ export function parseOptions(
     allOptions.set(key, values);
   }
 
+  if (allOptions.has('tlsCertificateKeyFile') && !allOptions.has('tlsCertificateFile')) {
+    allOptions.set('tlsCertificateFile', allOptions.get('tlsCertificateKeyFile'));
+  }
+
+  if (allOptions.has('tls') || allOptions.has('ssl')) {
+    const tlsAndSslOpts = (allOptions.get('tls') || [])
+      .concat(allOptions.get('ssl') || [])
+      .map(getBoolean.bind(null, 'tls/ssl'));
+    if (new Set(tlsAndSslOpts).size !== 1) {
+      throw new MongoParseError('All values of tls/ssl must be the same.');
+    }
+  }
+
   const unsupportedOptions = setDifference(
     allKeys,
     Array.from(Object.keys(OPTIONS)).map(s => s.toLowerCase())
@@ -384,18 +397,6 @@ export function parseOptions(
     mongoOptions.dbName = 'test';
   }
 
-  if (allOptions.has('tls')) {
-    if (new Set(allOptions.get('tls')?.map(getBoolean)).size !== 1) {
-      throw new MongoParseError('All values of tls must be the same.');
-    }
-  }
-
-  if (allOptions.has('ssl')) {
-    if (new Set(allOptions.get('ssl')?.map(getBoolean)).size !== 1) {
-      throw new MongoParseError('All values of ssl must be the same.');
-    }
-  }
-
   checkTLSOptions(mongoOptions);
 
   if (options.promiseLibrary) PromiseProvider.set(options.promiseLibrary);

src/mongo_client.ts

@@ -112,7 +112,7 @@ export interface MongoClientOptions extends BSONSerializeOptions, SupportedNodeC
   ssl?: boolean;
   /** Specifies the location of a local TLS Certificate */
   tlsCertificateFile?: string;
-  /** Specifies the location of a local .pem file that contains either the client’s TLS/SSL certificate or the client’s TLS/SSL certificate and key. */
+  /** Specifies the location of a local .pem file that contains either the client's TLS/SSL certificate and key or only the client's TLS/SSL key when tlsCertificateFile is used to provide the certificate. */
   tlsCertificateKeyFile?: string;
   /** Specifies the password to de-crypt the tlsCertificateKeyFile. */
   tlsCertificateKeyFilePassword?: string;

test/unit/core/connection_string.test.js

@@ -136,7 +136,7 @@ describe('Connection String', function () {
     it('should validate non-equal tls values', function () {
       expect(() => parseOptions('mongodb://localhost/?tls=true&tls=false')).to.throw(
         MongoParseError,
-        'All values of tls must be the same.'
+        'All values of tls/ssl must be the same.'
       );
     });
   });

test/unit/mongo_client_options.test.js

@@ -128,7 +128,7 @@ describe('MongoOptions', function () {
     ssl: true,
     sslPass: 'pass',
     sslValidate: true,
-    tls: false,
+    tls: true,
     tlsAllowInvalidCertificates: true,
     tlsAllowInvalidHostnames: true,
     tlsCertificateKeyFilePassword: 'tls-pass',
@@ -245,6 +245,18 @@ describe('MongoOptions', function () {
     expect(options).has.property('tls', false);
   });
 
+  it('ssl= can be used to set tls=true', function () {
+    const options = parseOptions('mongodb+srv://server.example.com/?ssl=true');
+    expect(options).has.property('srvHost', 'server.example.com');
+    expect(options).has.property('tls', true);
+  });
+
+  it('tls= can be used to set tls=true', function () {
+    const options = parseOptions('mongodb+srv://server.example.com/?tls=true');
+    expect(options).has.property('srvHost', 'server.example.com');
+    expect(options).has.property('tls', true);
+  });
+
   it('supports ReadPreference option in url', function () {
     const options = parseOptions('mongodb://localhost/?readPreference=nearest');
     expect(options.readPreference).to.be.an.instanceof(ReadPreference);
@@ -366,6 +378,83 @@ describe('MongoOptions', function () {
     expect(optionsUndefined.checkServerIdentity).to.equal(undefined);
   });
 
+  describe('[tls certificate handling]', () => {
+    before(() => {
+      fs.writeFileSync('testCertKey.pem', 'cert key');
+      fs.writeFileSync('testKey.pem', 'test key');
+      fs.writeFileSync('testCert.pem', 'test cert');
+    });
+
+    after(() => {
+      fs.unlinkSync('testCertKey.pem');
+      fs.unlinkSync('testKey.pem');
+      fs.unlinkSync('testCert.pem');
+    });
+
+    it('correctly sets the cert and key if only tlsCertificateKeyFile is provided', function () {
+      const optsFromObject = parseOptions('mongodb://localhost/', {
+        tlsCertificateKeyFile: 'testCertKey.pem'
+      });
+      expect(optsFromObject).to.have.property('cert', 'cert key');
+      expect(optsFromObject).to.have.property('key', 'cert key');
+
+      const optsFromUri = parseOptions('mongodb://localhost?tlsCertificateKeyFile=testCertKey.pem');
+      expect(optsFromUri).to.have.property('cert', 'cert key');
+      expect(optsFromUri).to.have.property('key', 'cert key');
+    });
+
+    it('correctly sets the cert and key if both tlsCertificateKeyFile and tlsCertificateFile is provided', function () {
+      const optsFromObject = parseOptions('mongodb://localhost/', {
+        tlsCertificateKeyFile: 'testKey.pem',
+        tlsCertificateFile: 'testCert.pem'
+      });
+      expect(optsFromObject).to.have.property('cert', 'test cert');
+      expect(optsFromObject).to.have.property('key', 'test key');
+
+      const optsFromUri = parseOptions(
+        'mongodb://localhost?tlsCertificateKeyFile=testKey.pem&tlsCertificateFile=testCert.pem'
+      );
+      expect(optsFromUri).to.have.property('cert', 'test cert');
+      expect(optsFromUri).to.have.property('key', 'test key');
+    });
+  });
+
+  it('throws an error if multiple tls parameters are not all set to the same value', () => {
+    expect(() => parseOptions('mongodb://localhost?tls=true&tls=false')).to.throw(
+      'All values of tls/ssl must be the same.'
+    );
+  });
+
+  it('throws an error if multiple ssl parameters are not all set to the same value', () => {
+    expect(() => parseOptions('mongodb://localhost?ssl=true&ssl=false')).to.throw(
+      'All values of tls/ssl must be the same.'
+    );
+  });
+
+  it('throws an error if tls and ssl parameters are not all set to the same value', () => {
+    expect(() => parseOptions('mongodb://localhost?tls=true&ssl=false')).to.throw(
+      'All values of tls/ssl must be the same.'
+    );
+    expect(() => parseOptions('mongodb://localhost?tls=false&ssl=true')).to.throw(
+      'All values of tls/ssl must be the same.'
+    );
+  });
+
+  it('correctly sets tls if multiple tls parameters are all set to the same value', () => {
+    expect(parseOptions('mongodb://localhost?tls=true&tls=true')).to.have.property('tls', true);
+    expect(parseOptions('mongodb://localhost?tls=false&tls=false')).to.have.property('tls', false);
+  });
+
+  it('correctly sets tls if multiple ssl parameters are all set to the same value', () => {
+    expect(parseOptions('mongodb://localhost?ssl=true&ssl=true')).to.have.property('tls', true);
+    expect(parseOptions('mongodb://localhost?ssl=false&ssl=false')).to.have.property('tls', false);
+  });
+
+  it('correctly sets tls if tls and ssl parameters are all set to the same value', () => {
+    expect(parseOptions('mongodb://localhost?ssl=true&tls=true')).to.have.property('tls', true);
+    expect(parseOptions('mongodb://localhost?ssl=false&tls=false')).to.have.property('tls', false);
+  });
+
   it('transforms tlsInsecure correctly', function () {
     const optionsTrue = parseOptions('mongodb://localhost/', {
       tlsInsecure: true