How do I test middleware in ASP.NET Core?

How do I test middleware in ASP.NET Core?

To test middleware in ASP.NET Core, you can use the built-in testing framework along with the TestServer class.

Can you show me a code example?

Sure! Here's a simple example:

public class MyMiddleware
{
    private readonly RequestDelegate _next;

    public MyMiddleware(RequestDelegate next)
    {
        _next = next;
    }

    public async Task InvokeAsync(HttpContext context)
    {
        // Middleware logic here
        await _next(context);
    }
}

// In your test:
var builder = new WebHostBuilder()
    .Configure(app => app.UseMiddleware<MyMiddleware>());
var server = new TestServer(builder);
var client = server.CreateClient();
var response = await client.GetAsync("/your-endpoint");

What should I be aware of when testing middleware?

When testing middleware, ensure you handle exceptions properly and test various scenarios, including edge cases.