asp.net - WebAPI : DelegatingHandler and ApiController on the same thread?

Question

在WebAPI自托管应用程序中，DelegatingHandler的SendAsync()方法和ApiController的任何方法是否总是在同一线程上执行？

使用[ThreadStatic]变量将RequestId从SessionHandler传递到TestController是否安全？

例子:

public class TestController : ApiController
{
    [HttpGet]
    public string Run()
    {
        LogManager.GetLogger("Controller").InfoFormat("Thread id: {0} ", Thread.CurrentThread.ManagedThreadId);
        return "Bar";
    }
}

public class SessionHandler : DelegatingHandler
{
    protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
    {
        LogManager.GetLogger("SessionHandler").InfoFormat("Thread id: {0} ", Thread.CurrentThread.ManagedThreadId);
        return await base.SendAsync(request, cancellationToken);
    }
}

Answer 1

In a WebAPI Self-Host application, will SendAsync() method of DelegatingHandler and any method of ApiController always execute on the same thread?

Is it safe to use [ThreadStatic] variable to pass RequestId from SessionHandler to TestController ?

不，不。 Web API上的 async将线程返回运行时，因此管道中的任何异步( Controller 操作，过滤器等)都可以在另一个线程上恢复。