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

JavaScript
/*As of this edit, Mongoose is now at v5.4.13. Per their docs, these are the fixes for the deprecation warnings..*/
mongoose.set('useNewUrlParser', true);
mongoose.set('useFindAndModify', false);
mongoose.set('useCreateIndex', true);mongoose.set('useNewUrlParser', true);
mongoose.set('useFindAndModify', false);
mongoose.set('useCreateIndex', true);
Source

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