HAproxy 心跳在命中 API 方法时不断抛出 "Task Cancelled exception"

Question

我们使用 HAproxy 和 httpchk 来验证我们的网站是否在每台服务器上正常运行。 httpchk方法的controller方法如下：

[Route("heartbeat")]
[HttpGet]
[AllowAnonymous]
public async Task<IHttpActionResult> Heartbeat()
{
    return Ok();
}

我们每天都会在错误日志中看到以下内容：

System.Threading.Tasks.TaskCanceledExceptionA task was canceled.

System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at System.Web.Http.Controllers.ApiControllerActionInvoker.<InvokeActionAsyncCore>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at System.Web.Http.Controllers.ActionFilterResult.<ExecuteAsync>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Web.Http.Filters.AuthorizationFilterAttribute.<ExecuteAuthorizationFilterAsyncCore>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at System.Web.Http.Controllers.ExceptionFilterResult.<ExecuteAsync>d__0.MoveNext()

有什么建议吗？

Answer 1

这似乎是 .NET 的一个错误 API 2。我们将其从 API 中删除并将其放入常规控制器方法中，错误停止了。这就是我们的目标：

[AllowAnonymous]
public HttpStatusCodeResult Heartbeat()
{
    return new HttpStatusCodeResult(HttpStatusCode.OK);
}

HAproxy 心跳在命中 API 方法时不断抛出 "Task Cancelled exception"

HAproxy heartbeat throws "Task Cancelled exception" constantly when hitting API method

c#

haproxy