MongoDB instrumentation not working with MongoClient.connect static method

[abreu-gyant]

Describe the bug

MongoDB instrumentation is not working when the MongoClient is created through the static method. Also, when creating the MongoClient through the constructor it only works if monitorCommands: true is set in the client options.

To Reproduce

Steps to reproduce the behavior:

import * as apm from 'elastic-apm-node';

apm.start({
  serviceName: 'MongoDB Test',
  serverUrl: 'http://localhost:8200/',
  logLevel: 'debug',
});

async function test() {
  const client = await MongoClient.connect('mongodb://localhost:27017/apm-test');
  const db = client.db();
  apm.startTransaction('test');
  const result = await db.listCollections().toArray();
  console.log(result);
  apm.endTransaction('end');
}

void test();

Expected behavior

APM spans of MongoDB should be logged.

Environment (please complete the following information)

• OS: macOS (11.3.1)
• Node.js version: v14.17.6
• APM Server version: 7.15.0
• Agent version: 3.24.0
• MongoDB: 4.2.0

How are you starting the agent? (please tick one of the boxes)

• Calling agent.start() directly (e.g. require('elastic-apm-node').start(...))
• Requiring elastic-apm-node/start from within the source code
• Starting node with -r elastic-apm-node/start

[trentm]

@abreu-gyant Thanks very much for the issue! I believe I will have a fix for both issues in #2512