Middleware (middleware)

Middleware (middleware)

ASP. NET core development, development and use of middleware (middleware).

Middleware is a software component that is assembled into an application pipeline to process requests and responses.

Each component chooses whether to pass a request to the next component in the pipeline and can perform a specific operation before and after the next component is called in the pipeline.

Specific

Development Middleware (middleware)

Today we will implement a middleware that records IP.

1. Create a new ASP. NET Core project and select an empty template.

Then add a Microsoft.Extensions.Logging.Console to the project

NuGet command line, please use the official source.

Install-package Microsoft.extensions.logging.console-pre

2. Create a new class: RequestIPMiddleware.cs

    public class Requestipmiddleware    {        private readonly requestdelegate _next;        Private ReadOnly ILogger _logger;        Public Requestipmiddleware (Requestdelegate Next, iloggerfactory loggerfactory)        {            _next = next;            _logger = loggerfactory.createlogger<requestipmiddleware> ();        }        Public Async Task Invoke (HttpContext context)        {                        _logger. Loginformation ("User IP:" + context.) Connection.RemoteIpAddress.ToString ());            Await _next. Invoke (context);        }    }

3. Create another one: RequestIPExtensions.cs

    public static class Requestipextensions    {public        static Iapplicationbuilder Userequestip (this Iapplicationbuilder builder)        {            return builder. Usemiddleware<requestipmiddleware> ();        }    }

So we've written a middleware.

Using Middleware (middleware)

1. Use

Add apps to Startup.cs. Userequestip ()

        public void Configure (Iapplicationbuilder app, Iloggerfactory loggerfactory)        {            loggerfactory. Addconsole (minLevel:LogLevel.Information);            App. Userequestip ();//Use middleware            app. Run (Async (context) =            {                await context. Response.writeasync ("Hello world!");}            );        

Then run the program and I choose to use Kestrel.

Visit: Http://localhost:5000/

Run successfully.

Here we can further improve the middleware, add more features, such as restricted access.

Middleware (middleware)