ASP.NET Core 6.0 - How to implement custom middleware for performance monitoring?
I've encountered a strange issue with I'm updating my dependencies and After trying multiple solutions online, I still can't figure this out... Can someone help me understand I'm updating my dependencies and I'm trying to implement a custom middleware in my ASP.NET Core 6.0 application to monitor the performance of my API endpoints. I want to log the time taken for each request and the response status code. However, I'm running into issues where the logs are showing the wrong duration for requests that involve async calls. Here's a snippet of my middleware code: ```csharp public class PerformanceMonitoringMiddleware { private readonly RequestDelegate _next; public PerformanceMonitoringMiddleware(RequestDelegate next) { _next = next; } public async Task InvokeAsync(HttpContext context) { var watch = System.Diagnostics.Stopwatch.StartNew(); await _next(context); watch.Stop(); var duration = watch.ElapsedMilliseconds; var statusCode = context.Response.StatusCode; // Log the duration and status code (using a hypothetical logging service) Console.WriteLine($"Request to {context.Request.Path} took {duration} ms and returned status {statusCode}."); } } ``` I registered the middleware in the `Startup.cs` like this: ```csharp public void Configure(IApplicationBuilder app, IWebHostEnvironment env) { // Other middleware registrations... app.UseMiddleware<PerformanceMonitoringMiddleware>(); // More middleware registrations... } ``` The issue arises when I make requests to endpoints that utilize asynchronous operations, such as database calls using Entity Framework Core. For instance, when I send a request to an endpoint that retrieves data, the logged duration often appears to be much shorter than expected, sometimes even showing zero milliseconds. I've tried adding logging before and after the `_next(context)` call, but it seems that the stopwatch is stopping too early. Is there a known issue with how the execution flow works with async operations in middleware, or is there something I am missing in the implementation? Any insights or recommendations on best practices for logging performance metrics would be greatly appreciated! I'm on Ubuntu 22.04 using the latest version of Csharp. Thanks in advance! My development environment is Debian. What's the best practice here? Thanks for any help you can provide! I'm working on a web app that needs to handle this. Any examples would be super helpful.