mongoose.connect('mongodb://localhost/myapp', { useNewUrlParser: true, useUnifiedTopology: true });
mongoose.connect('mongodb://localhost:27017/test', { useMongoClient: true, connectTimeoutMS: 1000 })
try { mongoose.connect(MONGODB_URI || 'mongodb://localhost/YOUR_DB_NAME', { useNewUrlParser: true, useUnifiedTopology: true }, () => console.log("connected")); } catch (error) { console.log("could not connect"); }