Mongoose Promise error

Question

This is the error which is still being thrown when saving even after adding native promise.

(node:5604) DeprecationWarning: Mongoose: mpromise (mongoo

Answer 1

Despite using mongoose.Promise = global.Promise; before mongoose.connect(...), I had the same warning.

I discovered, that I initialized mongoose connection in one file:

import mongoose from 'mongoose';

...

// Connect to MongoDB
mongoose.Promise = global.Promise;
mongoose.connect(mongoUri, mongoOptions);
mongoose.connection.on('error', (err) => {
  console.error(`MongoDB connection error: ${err}`);
  process.exit(1);
});

But I imported mongoose in another file too (where mongoose scheme was described), so I added mongoose.Promise = global.Promise; in second file too, as a result of it, the warning disappeared.

import mongoose, { Schema } from 'mongoose';
mongoose.Promise = global.Promise;

const UserSchema = new Schema({ ... });

May be you have the same case.