ASP.NET Core Interview Question #78
Why is middleware order important in ASP.NET Core?
Middleware & Request Pipeline Mid-Level Intermediate
Quick Interview Answer
Middleware order determines which components see a request and when they run. Incorrect ordering can cause authentication, authorization, routing, static files, CORS, or exception handling to behave incorrectly.
Detailed Explanation
Middleware order determines which components see a request and when they run. Incorrect ordering can cause authentication, authorization, routing, static files, CORS, or exception handling to behave incorrectly.
For example, authentication should normally run before authorization so the user identity is available when authorization policies are evaluated. Exception handling should be placed early enough to catch exceptions from downstream middleware.
Endpoint mapping also interacts with the pipeline, so the application's chosen routing style should follow the recommended order for the ASP.NET Core version and features being used.
Code Example
app.UseExceptionHandler("/Home/Error");
app.UseHttpsRedirection();
app.UseStaticFiles();
app.UseRouting();
app.UseAuthentication();
app.UseAuthorization();
app.MapControllers();