fix: add user provided transport to the logger (#543)

Author: laljikanjareeya

handwritten/logging-winston/src/middleware/express.ts

@@ -47,10 +47,10 @@ export async function makeMiddleware(
     const options = {logName: 'winston_log', ...optionsOrTransport};
 
     transport = new LoggingWinston(options);
-    logger.add(transport);
   } else {
     transport = optionsOrTransport;
   }
+  logger.add(transport);
 
   const auth = transport.common.stackdriverLog.logging.auth;
   const [env, projectId] = await Promise.all([

handwritten/logging-winston/test/middleware/express.ts

@@ -113,6 +113,13 @@ describe('middleware/express', () => {
     assert.strictEqual(logger.transports[0], transport);
   });
 
+  it('should add a user provided transport to the logger', async () => {
+    const t = new FakeLoggingWinston({});
+    await makeMiddleware(logger, t);
+    assert.strictEqual(logger.transports.length, 1);
+    assert.strictEqual(logger.transports[0], t);
+  });
+
   it('should create a transport with the correct logName', async () => {
     await makeMiddleware(logger);
     assert.ok(passedOptions);