– Middleware is a piece of code in an application pipeline used to handle requests and responses.

– we may have a middleware component to authenticate a user, another piece of middleware to handle errors, and another middleware to serve static files such as JavaScript files, CSS files, images, etc.

– Middleware can be built-in as part of the .NET Core framework, added via NuGet packages, or can be custom middleware.

– These middleware components are configured as part of the application startup class in the configure method.

– Configure methods set up a request processing pipeline for an ASP.NET Core application. It consists of a sequence of request delegates called one after the other

– Middleware component can decide not to call the next piece of middleware in the pipeline. This is called short-circuiting or terminating the request pipeline.

– Short-circuiting is often desirable because it avoids unnecessary work.

– Middleware components are executed in the order they are added to the pipeline, and care should be taken to add the middleware in the right order; otherwise, the application may not function as expected.

– This ordering is critical for security, performance, and functionality.

– Some middleware components may expose Run[Middleware] methods that run at the end of the pipeline

Below are Middleware typically consists of components

· Management console. Provides an overview of the middleware’s activities and configurations.

· Client interface.

· Internal interface.

· Platform interface.

· Contract manager.

· Session manager.

· Database manager.

· Runtime monitor.