Connecting mongoose to AWS documentDB

Question

I am trying to connect a NodeJS server to an AWS documentDB cluster with TLS enabled. The NodeJS server is hosted on an EC2 instance and it's on the same VPC as the documentDB cluster. But I'm getting the following error:

{ MongoServerSelectionError: unable to get local issuer certificate
     at Timeout.waitQueueMember.timer.setTimeout [as _onTimeout] (/home/ubuntu/server/node_modules/mongodb/lib/core/sdam/topology.js:438:30)
     at ontimeout (timers.js:436:11)
     at tryOnTimeout (timers.js:300:5)
     at listOnTimeout (timers.js:263:5)
     at Timer.processTimers (timers.js:223:10)
   name: 'MongoServerSelectionError',
   reason:
    TopologyDescription {
      type: 'ReplicaSetNoPrimary',
      setName: null,
      maxSetVersion: null,
      maxElectionId: null,
      servers:
       Map {
         '*******.cluster-****.us-east-1.docdb.amazonaws.com:27017' => [ServerDescription] },
      stale: false,
      compatible: true,
      compatibilityError: null,
      logicalSessionTimeoutMinutes: null,
      heartbeatFrequencyMS: 10000,
      localThresholdMS: 15,
      commonWireVersion: null } }

The error seems to be with the TLS certificate. But I'm passing the contents of rds-combined-ca-bundle.pem while connecting as shown in the following code:

uri = process.env.MONGODB_URI || process.env.Db_url;
options = {
    user: "****",
    pass: "****",
}
mongoose.set("useCreateIndex", true);
mongoose.connect(
  uri,
  {
    useNewUrlParser: true,
    useFindAndModify: false,
    useUnifiedTopology: true,
    sslCA: [fs.readFileSync("/home/ubuntu/rds-combined-ca-bundle.pem")],
  },
  err => {
    if (err) {
      console.log('Connection Error: ', err);
    } else {
      console.log(`Successfully Connected============`);
    }
  }
);     

I've tried connecting to the mongo cluster using mongo shell on EC2 instance using

mongo --ssl --host *******.cluster-****.us-east-1.docdb.amazonaws.com:27017 \
--sslCAFile rds-combined-ca-bundle.pem --username ***** --password *****

and this is working. So, the connection to the cluster is fine, but the mongoose cannot connect.

Is there any other way to connect to documentDB using mongoose?

Answer 1

Can you add ssl: true? Something like this works for me:

const mongoose = require('mongoose');

main().catch(err => console.log(err));

async function main() {
  await mongoose.connect('mongodb://user:password@docdb_uri',
      {
          useNewUrlParser: true,
          ssl: true,
          sslValidate: true,
          sslCA: `/usr/local/rds-combined-ca-bundle.pem`
      })
}