Creating custom middleware

Middleware is an API component that allows you to intercept and modify incoming requests and outgoing responses, making it a powerful tool for implementing cross-cutting concerns such as authentication, logging, and error handling.

In this recipe, we’ll explore how to develop custom middleware to process requests and responses in FastAPI applications and retrieve information on the client.

Getting ready…

All you need is to have a running FastAPI application. The recipe will use our trip platform defined in the previous recipe, Implementing dependency injection. However, middleware works for a generic running application.

How to do it…

We will show you how to create a custom middleware object class that we will use in our application through the following steps.

1. Let’s create a dedicated module in the app folder called middleware.py.

   We want the middleware to intercept the request and print the host client and...