Performance - Timeouts middleware

In this article

Add the middleware to the app

Note

In apps that explicitly call UseRouting, UseRequestTimeouts must be called after UseRouting.

Configure one endpoint or page

using Microsoft.AspNetCore.Http.Timeouts;

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddRequestTimeouts();

var app = builder.Build();
app.UseRequestTimeouts();

app.MapGet("/", async (HttpContext context) => {
    try
    {
        await Task.Delay(TimeSpan.FromSeconds(10), context.RequestAborted);
    }
    catch (TaskCanceledException)
    {
        return Results.Content("Timeout!", "text/plain");
    }

    return Results.Content("No timeout!", "text/plain");
}).WithRequestTimeout(TimeSpan.FromSeconds(2));
// Returns "Timeout!"

app.MapGet("/attribute",
    [RequestTimeout(milliseconds: 2000)] async (HttpContext context) => {
        try
        {
            await Task.Delay(TimeSpan.FromSeconds(10), context.RequestAborted);
        }
        catch (TaskCanceledException)
        {
            return Results.Content("Timeout!", "text/plain");
        }

        return Results.Content("No timeout!", "text/plain");
    });
// Returns "Timeout!"

app.Run();

Configure multiple endpoints or pages

builder.Services.AddRequestTimeouts(options => {
    options.DefaultPolicy =
        new RequestTimeoutPolicy { Timeout = TimeSpan.FromMilliseconds(1500) };
    options.AddPolicy("MyPolicy", TimeSpan.FromSeconds(2));
});

app.MapGet("/namedpolicy", async (HttpContext context) => {
    try
    {
        await Task.Delay(TimeSpan.FromSeconds(10), context.RequestAborted);
    }
    catch (TaskCanceledException)
    {
        return Results.Content("Timeout!", "text/plain");
    }

    return Results.Content("No timeout!", "text/plain");
}).WithRequestTimeout("MyPolicy");
// Returns "Timeout!"

Set global default timeout policy

builder.Services.AddRequestTimeouts(options => {
    options.DefaultPolicy =
        new RequestTimeoutPolicy { Timeout = TimeSpan.FromMilliseconds(1500) };
    options.AddPolicy("MyPolicy", TimeSpan.FromSeconds(2));
});

app.MapGet("/", async (HttpContext context) => {
    try
    {
        await Task.Delay(TimeSpan.FromSeconds(10), context.RequestAborted);
    }
    catch
    {
        return Results.Content("Timeout!", "text/plain");
    }

    return Results.Content("No timeout!", "text/plain");
});
// Returns "Timeout!" due to default policy.

Specify the status code in a policy

builder.Services.AddRequestTimeouts(options => {
    options.DefaultPolicy = new RequestTimeoutPolicy {
        Timeout = TimeSpan.FromMilliseconds(1000),
        TimeoutStatusCode = 503
    };
    options.AddPolicy("MyPolicy2", new RequestTimeoutPolicy {
        Timeout = TimeSpan.FromMilliseconds(1000),
        WriteTimeoutResponse = async (HttpContext context) => {
            context.Response.ContentType = "text/plain";
            await context.Response.WriteAsync("Timeout from MyPolicy2!");
        }
    });
});

app.MapGet("/", async (HttpContext context) => {
    try
    {
        await Task.Delay(TimeSpan.FromSeconds(10), context.RequestAborted);
    }
    catch (TaskCanceledException)
    {
        throw;
    }

    return Results.Content("No timeout!", "text/plain");
});
// Returns status code 503 due to default policy.

Use a delegate in a policy

builder.Services.AddRequestTimeouts(options => {
    options.DefaultPolicy = new RequestTimeoutPolicy {
        Timeout = TimeSpan.FromMilliseconds(1000),
        TimeoutStatusCode = 503
    };
    options.AddPolicy("MyPolicy2", new RequestTimeoutPolicy {
        Timeout = TimeSpan.FromMilliseconds(1000),
        WriteTimeoutResponse = async (HttpContext context) => {
            context.Response.ContentType = "text/plain";
            await context.Response.WriteAsync("Timeout from MyPolicy2!");
        }
    });
});

app.MapGet("/usepolicy2", async (HttpContext context) => {
    try
    {
        await Task.Delay(TimeSpan.FromSeconds(10), context.RequestAborted);
    }
    catch (TaskCanceledException)
    {
        throw;
    }

    return Results.Content("No timeout!", "text/plain");
}).WithRequestTimeout("MyPolicy2");
// Returns "Timeout from MyPolicy2!" due to WriteTimeoutResponse in MyPolicy2.

Disable timeouts

app.MapGet("/disablebyattr", [DisableRequestTimeout] async (HttpContext context) => {
    try
    {
        await Task.Delay(TimeSpan.FromSeconds(10), context.RequestAborted);
    }
    catch
    {
        return Results.Content("Timeout!", "text/plain");
    }

    return Results.Content("No timeout!", "text/plain");
});
// Returns "No timeout!", ignores default timeout.

app.MapGet("/disablebyext", async (HttpContext context) => {
    try
    {
        await Task.Delay(TimeSpan.FromSeconds(10), context.RequestAborted);
    }
    catch
    {
        return Results.Content("Timeout!", "text/plain");
    }

    return Results.Content("No timeout!", "text/plain");
}).DisableRequestTimeout();
// Returns "No timeout!", ignores default timeout.

Cancel a timeout

app.MapGet("/canceltimeout", async (HttpContext context) => {
    var timeoutFeature = context.Features.Get<IHttpRequestTimeoutFeature>();
    timeoutFeature?.DisableTimeout();

    try
    {
        await Task.Delay(TimeSpan.FromSeconds(10), context.RequestAborted);
    } 
    catch (TaskCanceledException)
    {
        return Results.Content("Timeout!", "text/plain");
    }

    return Results.Content("No timeout!", "text/plain");
}).WithRequestTimeout(TimeSpan.FromSeconds(1));
// Returns "No timeout!" since the default timeout is not triggered.

See also

• Microsoft.AspNetCore.Http.Timeouts

• ASP.NET Core Middleware

Ref: Request timeouts middleware in ASP.NET Core