working with. mongoose code example
Example 1: node js + mongoose
await mongoose.connect('mongodb://localhost/my_database', { useNewUrlParser: true, useUnifiedTopology: true});
Example 2: node js + mongoose
const db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function() {
// we're connected!
});