(node:71307) [DEP0079] DeprecationWarning

You have to not worry about this error this is mongoose warning . Actually Mongoose use inspect() to debug output . they will update it may be before node 12.x . For now it is safe to use this.

Nothing to worry.

Check this info. https://nodejs.org/api/deprecations.html#deprecations_dep0079_custom_inspection_function_on_objects_via_inspect

DEP0079: Custom inspection function on Objects via .inspect()# Type: Runtime

Using a property named inspect on an object to specify a custom inspection function for util.inspect() is deprecated. Use util.inspect.custom instead. For backward compatibility with Node.js prior to version 6.4.0, both may be specified.

If you want more detail, see this . This is under progress. Warning will come in node 10

https://github.com/Automattic/mongoose/issues/6420

In order to not get the deprecation message you can upgrade to mongoose version 5.2.10 or later according to this Github mongoose issue and the set the following at a proper location in code:

mongoose.set('useCreateIndex', true)

upgrade to 5.2.10 and set

  mongoose.set('useCreateIndex', true);