Implementing an endpoint to update a note using HTTP verb PUT

To update Note, we will implement the endpoint that meets specific requirements. Let's make a list of these requirements for our update endpoint to gain an understanding of what the request and response should look like.

The request is expected to meet the following criteria:

• The HTTP method will be PUT.
• The HTTP route will be /notes/:id.
• The request body will have a payload representing a Note in JSON format.

The response is expected to meet the following criteria:

• When a malformed JSON is present in the request payload, the following will occur:
  • The response body will have a CustomResponse struct encoded into JSON with a reasonable message.
  • The status code will show 400, Bad Request.
• If the proper JSON payload of the Note is present in the request body, do the following:
  • Check whether the Note to be updated exists in the database using the built-in orm-based syntax.
• When a Note...