connect mongoose to atlas
const mongoAtlasUri =
  "mongodb+srv://[email protected]:[email protected]/DB_NAme?retryWrites=true&w=majority";
try {
  // Connect to the MongoDB cluster
  mongoose.connect(
    mongoAtlasUri,
    { useNewUrlParser: true, useUnifiedTopology: true },
    () => console.log(" Mongoose is connected")
  );
} catch (e) {
  console.log("could not connect");
}
