Create express based APIs to upload and download files to and from MongoDB GridFS.

Lean option on Query

While returning data from the database as an API response, the virtuals/methods available on a mongoose document are unnecessary. Lean option can be set on such queries to return just the data directly from the database. It also improves the overall performance of the API.

Model Relations

Relations are logical links which define how models are connected with each other. A document of a model can be connected to one or more documents of the same or another model.