nodejs collection.ensureIndex is deprecated. Use createIndexes instead. code example

Example 1: (node:2736) DeprecationWarning: collection.ensureIndex is deprecated. Use createIndexes instead.

mongoose.connect(
  url,
  {useCreateIndex: true },
  () => {
    console.log("MongoDB is connected!");
  }
);

Example 2: (node:2496) DeprecationWarning: collection.ensureIndex is deprecated. Use createIndexes instead.

mongoose.set('useNewUrlParser', true);
mongoose.set('useFindAndModify', false);
mongoose.set('useCreateIndex', true);