Middleware functions are those functions having access to the request object (req), the response object (res), and also the next function in an application's request-response cycle. The following function is basically a function in the Express router, when invoked, executes the middleware which is succeeding in the current middleware.

Middlewares can perform the following tasks:
  • Execute any type of code
  • Making changes to the request and response objects
  • We are ending the request-response cycle.
  • Cleaning the next middleware in the stack
BY Best Interview Question ON 25 Jun 2020