Creating Custom Middleware

Guide to creating custom middleware using the `BaseMiddleware` class.

Middleware in web applications sits between the request and the response, allowing you to intercept and process requests before they reach the main view and responses before they are returned to the client. Here’s how you can create custom middleware based on the BaseMiddleware class.

1. Define Your Custom Middleware Class

# middleware.py
from blazingapi.middleware import BaseMiddleware


class MyCustomMiddleware(BaseMiddleware):

    def execute_before(self, request):
        """
        Implement actions to perform before the view or next middleware is called.
        For example, you can log the request details or modify headers.
        """
        # Example: Logging request details
        print(f"Request method: {request.method}. Request path: {request.path}")

    def execute_after(self, request, response):
        """
        Implement actions to perform after the view or next middleware is called.
        This is called in reverse order of middleware stack after the response is generated.
        """
        # Example: Modifying response data
        response.headers['X-Processed-By'] = 'MyCustomMiddleware'

2. Register Your Middleware in settings.py

Add your custom middleware class to the MIDDLEWARE_CLASSES list in settings.py to include it in the middleware stack.

# settings.py
MIDDLEWARE_CLASSES = [
    "middleware.MyCustomMiddleware",
    "blazingapi.middleware.CorsMiddleware",
    "blazingapi.auth.middleware.BearerAuthenticationMiddleware",
    ...
]

3. Middleware Execution Order

Middleware components are executed in the order they are added in settings.py. The execute_before method is called in the order of the middleware stack, starting from the first middleware component added to the application. The execute_after method is called in reverse order of the middleware stack.

For a more detailed explanation, refer to the Middleware Execution Order documentation.