What is Request Pipeline?

Usman Pervez — Fri, 20 Mar 2026 07:42:26 +0000

The request pipeline is simply:

The path an HTTP request follows inside ASP.NET Core before a response is returned.

Think of it like a chain of steps.

When a user sends a request like:

https://yourwebsite.com/api/users

that request does NOT directly go to the controller.

Instead, it passes through multiple stages first.

How the pipeline actually works

Imagine this flow:

Client → Server → Middleware 1 → Middleware 2 → Middleware 3 → Controller → Response → Back through middleware → Client

So every request must pass through middleware before reaching the controller.

And every response passes back through the same pipeline.

When someone opens your API endpoint:

GET /api/users

ASP.NET Core processes it like this:

This entire flow is called the request pipeline.

User → Controller → Response

But real flow is:

User → Middleware → Routing → Controller → Middleware → Response

Middleware is a small piece of code that:

Example:

Authentication middleware:

So middleware controls the entire request flow.

Open this file:

Program.cs

You’ll see lines like this:

app.UseAuthentication();
app.UseAuthorization();
app.MapControllers();

These lines define the order of the request pipeline.
And the order is extremely important.

I Hope you get the concept, Thank You.