Middleware to Asp.net Core MVC Application + Custom Middleware

Hello everyone,

Today, I’m excited to guide you through the process of adding custom middleware to your application. Middleware is a vital component of any application, and understanding how to effectively use it can greatly enhance your development process.

Why Middleware Matters

Middleware is crucial in handling all requests and responses in your application. By leveraging middleware, you can streamline and manage various tasks such as:

Authentication: Verifying user identity.
Authorization: Checking user permissions.
Logging: Recording details about requests and responses.
Error Handling: Catching and managing exceptions.

Using middleware can save you significant time and effort by centralizing and simplifying these common tasks.

What is Middleware?

Middleware is a piece of code (or a component) that sits in the HTTP request-response pipeline. It has access to all incoming requests and outgoing responses, allowing it to process or manipulate them. Middleware can log information, modify requests/responses, or even terminate requests early.

Common Examples of Middleware

Some commonly used middleware includes:

Authentication Middleware: Verifies user identity.
Authorization Middleware: Checks user permissions.
Logging Middleware: Logs details about requests and responses.
Exception Handling Middleware: Catches and handles exceptions.
Static Files Middleware: Serves static files like images, CSS, and JavaScript.

public class Startup
{
    public void Configure(IApplicationBuilder app, IHostingEnvironment env)
    {
        // Add custom middleware
        app.Use(async (context, next) =>
        {
            await context.Response.WriteAsync("Hello from Middleware");
            await next(); // Call the next middleware in the pipeline
        });

        // Other middleware registrations
        app.UseStaticFiles();
        app.UseAuthentication();
        app.UseMvc();
    }
}

Adding Custom Middleware

Let’s walk through the process of adding a custom middleware that writes "Hello from Middleware" to every response.

Steps to Add Custom Middleware
Open Startup.cs: This file configures your application's request pipeline.
Modify the Configure Method: Add your custom middleware within the Configure method.

I hope this helps you understand how to integrate custom middleware into your application. Happy coding!`