Incomplete key value pair for option remote mongodb

问题

I'm trying to deploy my local node mongoDB app to Heroku. Everything is working fine on my local machine, no errors.

First thing I'm trying to do is to connect to a database on mlab. It seen very straight forward but I get this error:

err { MongoParseError: Incomplete key value pair for option
  name: 'MongoParseError',
  message: 'Incomplete key value pair for option',
  [Symbol(mongoErrorContextSymbol)]: {} }

My code looks like this:

    var mongoose = require('mongoose');

    const options = {
            useNewUrlParser: true
          };

    mongoose.connect("mongodb://username:password@xxxxx.mlab.com:39251/nameodDB",options).then(
   ()=>{
      console.log("connected to mongoDB")},
   (err)=>{
       console.log("err",err);
 });

来源：https://stackoverflow.com/questions/51352077/incomplete-key-value-pair-for-option-remote-mongodb