DeprecationWarning: current Server Discovery and Monitoring engine is deprecated, and will be removed in a future version. To use the new Server Discover and Monitoring engine, pass option code example

Example 1: DeprecationWarning: current Server Discovery and Monitoring engine is deprecated,

mongoose.connect("paste db link", {useUnifiedTopology: true, useNewUrlParser: true, useCreateIndex: true });

mongoose.connect(uri, { useNewUrlParser: true,useUnifiedTopology:true });
mongoose.createConnection(uri, { useNewUrlParser: true });