如何为C#MVC4 WebAPI应用程序全局记录所有异常？

Question

背景

我正在为客户开发API服务层,并且我被要求在全局范围内捕获并记录所有错误.

因此,虽然通过使用ELMAH或通过向以下内容添加类似内容,可以轻松处理类似未知端点(或操作)的内容Global.asax:

protected void Application_Error()
{
     Exception unhandledException = Server.GetLastError();
     //do more stuff
}

...不会记录与路由无关的未处理错误.例如:

public class ReportController : ApiController
{
    public int test()
    {
        var foo = Convert.ToInt32("a");//Will throw error but isn't logged!!
        return foo;
    }
}

我还尝试[HandleError]通过注册此过滤器来全局设置该属性:

filters.Add(new HandleErrorAttribute());

但这也不会记录所有错误.

问题/疑问

如何拦截错误,例如通过调用/test上面生成的错误,以便我可以记录它们？似乎这个答案应该是显而易见的,但我已经尝试了迄今为止我能想到的一切.

理想情况下,我想在错误记录中添加一些内容,例如请求用户的IP地址,日期,时间等.我还希望能够在遇到错误时自动通过电子邮件发送支持人员.所有这些我都可以做到,只要我能在它们发生时拦截这些错误!

解决!

感谢Darin Dimitrov,我接受了他的回答,我弄清楚了. 的WebAPI并没有以同样的方式作为一个普通MVC控制器处理错误.

这是有效的:

1)在命名空间中添加自定义过滤器:

public class ExceptionHandlingAttribute : ExceptionFilterAttribute
{
    public override void OnException(HttpActionExecutedContext context)
    {
        if (context.Exception is BusinessException)
        {
            throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError)
            {
                Content = new StringContent(context.Exception.Message),
                ReasonPhrase = "Exception"
            });

        }

        //Log Critical errors
        Debug.WriteLine(context.Exception);

        throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError)
        {
            Content = new StringContent("An error occurred, please try again or contact the administrator."),
            ReasonPhrase = "Critical Exception"
        });
    }
}

2)现在在WebApiConfig类中全局注册过滤器:

public static class WebApiConfig
{
     public static void Register(HttpConfiguration config)
     {
         config.Routes.MapHttpRoute("DefaultApi", "api/{controller}/{action}/{id}", new { id = RouteParameter.Optional });
         config.Filters.Add(new ExceptionHandlingAttribute());
     }
}

或者您可以跳过注册,只使用[ExceptionHandling]属性装饰一个控制器.

Answer 1

作为以前答案的补充.

昨天,ASP.NET Web API 2.1正式发布.
它提供了另一个处理全球异常的机会.
详细信息在样本中给出.

简而言之,您添加全局异常记录器和/或全局异常处理程序(只有一个).
您将它们添加到配置:

public static void Register(HttpConfiguration config)
{
  config.MapHttpAttributeRoutes();

  // There can be multiple exception loggers.
  // (By default, no exception loggers are registered.)
  config.Services.Add(typeof(IExceptionLogger), new ElmahExceptionLogger());

  // There must be exactly one exception handler.
  // (There is a default one that may be replaced.)
  config.Services.Replace(typeof(IExceptionHandler), new GenericTextExceptionHandler());
}

他们的实现:

public class ElmahExceptionLogger : ExceptionLogger
{
  public override void Log(ExceptionLoggerContext context)
  {
    ...
  }
}

public class GenericTextExceptionHandler : ExceptionHandler
{
  public override void Handle(ExceptionHandlerContext context)
  {
    context.Result = new InternalServerErrorTextPlainResult(
      "An unhandled exception occurred; check the log for more information.",
      Encoding.UTF8,
      context.Request);
  }
}

Answer 2

如果您的Web API托管在ASP.NET应用程序中,Application_Error则将为您的代码中的所有未处理异常调用该事件,包括您显示的测试操作中的异常.因此,您所要做的就是在Application_Error事件中处理此异常.在您显示的示例代码中,您只处理类型的异常,HttpException这显然不是Convert.ToInt32("a")代码的情况.因此,请确保您记录并处理其中的所有异常:

protected void Application_Error()
{
    Exception unhandledException = Server.GetLastError();
    HttpException httpException = unhandledException as HttpException;
    if (httpException == null)
    {
        Exception innerException = unhandledException.InnerException;
        httpException = innerException as HttpException;
    }

    if (httpException != null)
    {
        int httpCode = httpException.GetHttpCode();
        switch (httpCode)
        {
            case (int)HttpStatusCode.Unauthorized:
                Response.Redirect("/Http/Error401");
                break;

            // TODO: don't forget that here you have many other status codes to test 
            // and handle in addition to 401.
        }
        else
        {
            // It was not an HttpException. This will be executed for your test action.
            // Here you should log and handle this case. Use the unhandledException instance here
        }
    }
}

Web API中的异常处理可以在各个级别完成.这是一个detailed article解释不同的可能性:

• 自定义异常过滤器属性,可以注册为全局异常过滤器

  [AttributeUsage(AttributeTargets.All)]
  public class ExceptionHandlingAttribute : ExceptionFilterAttribute
  {
      public override void OnException(HttpActionExecutedContext context)
      {
          if (context.Exception is BusinessException)
          {
              throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError)
              {
                  Content = new StringContent(context.Exception.Message),
                  ReasonPhrase = "Exception"
              });
          }
  
          //Log Critical errors
          Debug.WriteLine(context.Exception);
  
          throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError)
          {
              Content = new StringContent("An error occurred, please try again or contact the administrator."),
              ReasonPhrase = "Critical Exception"
          });
      }
  }
  

• 自定义动作调用者

  public class MyApiControllerActionInvoker : ApiControllerActionInvoker
  {
      public override Task<HttpResponseMessage> InvokeActionAsync(HttpActionContext actionContext, System.Threading.CancellationToken cancellationToken)
      {
          var result = base.InvokeActionAsync(actionContext, cancellationToken);
  
          if (result.Exception != null && result.Exception.GetBaseException() != null)
          {
              var baseException = result.Exception.GetBaseException();
  
              if (baseException is BusinessException)
              {
                  return Task.Run<HttpResponseMessage>(() => new HttpResponseMessage(HttpStatusCode.InternalServerError)
                  {
                      Content = new StringContent(baseException.Message),
                      ReasonPhrase = "Error"
  
                  });
              }
              else
              {
                  //Log critical error
                  Debug.WriteLine(baseException);
  
                  return Task.Run<HttpResponseMessage>(() => new HttpResponseMessage(HttpStatusCode.InternalServerError)
                  {
                      Content = new StringContent(baseException.Message),
                      ReasonPhrase = "Critical Error"
                  });
              }
          }
  
          return result;
      }
  }
  

Answer 3

为什么要重新抛出？这有效,它将使服务返回状态500等

public class LogExceptionFilter : ExceptionFilterAttribute
{
    private static readonly ILog log = LogManager.GetLogger(typeof (LogExceptionFilter));

    public override void OnException(HttpActionExecutedContext actionExecutedContext)
    {
        log.Error("Unhandeled Exception", actionExecutedContext.Exception);
        base.OnException(actionExecutedContext);
    }
}