Azure App Service: HTTP 500 scenarios When Using Custom Middleware in ASP.NET Core
I'm attempting to set up I'm trying to figure out I'm experiencing an HTTP 500 behavior when deploying my ASP.NET Core application to Azure App Service, specifically when I include a custom middleware for logging... Locally, everything works as expected, but once I deploy to Azure, I get the following behavior in the Application Insights logs: ``` System.Exception: An behavior occurred while processing your request. ---> System.NullReferenceException: Object reference not set to an instance of an object. ``` The middleware I'm using is meant to log HTTP requests and responses. Here’s a snippet of the middleware code: ```csharp public class CustomLoggingMiddleware { private readonly RequestDelegate _next; public CustomLoggingMiddleware(RequestDelegate next) { _next = next; } public async Task InvokeAsync(HttpContext context) { // Log request information var requestBody = await new StreamReader(context.Request.Body).ReadToEndAsync(); // Perform logging with requestBody... context.Response.OnStarting(() => { // Log response information // Attempt to log the response body here... return Task.CompletedTask; }); await _next(context); } } ``` I've ensured that my custom middleware is correctly registered in the `Configure` method: ```csharp public void Configure(IApplicationBuilder app, IWebHostEnvironment env) { app.UseMiddleware<CustomLoggingMiddleware>(); // Other middleware registrations... } ``` I also checked the Azure App Service settings and made sure that `ASPNETCORE_ENVIRONMENT` is set to `Production`. The behavior doesn't give much detail, and my logging inside Azure isn't showing anything specific before the exception is thrown. I've also tried enabling Application Insights to get more insights, but so far, I haven't been able to pinpoint the scenario. It's worth mentioning that this middleware works perfectly fine in a local IIS Express environment. How can I debug this further or what could be causing the `NullReferenceException` in Azure? Any help would be greatly appreciated! My development environment is Linux. I've been using Csharp for about a year now. I'm open to any suggestions.