首先是一些背景知识.
我在Visual Studio 2017社区中使用.Net Framework 4.6.1,Microsoft.AspNet.WebApi 5.2.4.
我的ApiController的实现端点会抛出预期的异常,例如,如果不满足某些要求.我添加了全局ExceptionFilterAttribute和ExceptionHandler来处理这些异常并返回正确的响应.
异常是一种继承System.Exception的类型.
这只是偶尔按预期工作.每隔一秒或三分之一或有时第五(没有实际模式)请求api服务器根本不返回任何响应,例如例如Postman说:“无法得到任何回应”.
为了测试这个,我使用了具有相同输入的相同端点.
以下是我为了更好地了解问题所做的一些事情:
我向Global.asax添加了异常日志记录(以捕获First Chance Exceptions)
我订阅了Global.asax Application_Error事件
我查看了IIS日志
没有人让我更接近这个问题.异常被捕获并记录在Global.asax中,就像预期的那样,但是没有其他错误或异常可以为我的问题提供更多信息.
这是我的代码:
我简化了ApiController的功能并删除了业务逻辑.
[Route("test")]
[HttpGet]
public IHttpActionResult GetTest()
{
throw new ObjectAlreadyExistsException("test");
return ResponseFactory.CreateOkResponse(null);
}
public class ExceptionFilter : ExceptionFilterAttribute
{
public override void OnException(HttpActionExecutedContext context)
{
if (context.Exception is ObjectAlreadyExistsException)
{
context.Response = ResponseFactory.CreateErrorResponseMessage(context.Exception.Message, new Error("OBJECT_ALREADY_EXISTS_ERROR", context.Exception.Message));
}
else if (context.Exception is ObjectNotFoundException)
{
context.Response = ResponseFactory.CreateErrorResponseMessage(context.Exception.Message, new Error("OBJECT_NOT_FOUND_ERROR", context.Exception.Message));
}
base.OnException(context);
}
}
public class GlobalExceptionHandler : ExceptionHandler
{
private static readonly ILogger Log = new LoggerConfiguration()
.WriteTo.File(new CompactJsonFormatter(), Path.Combine(@Properties.Settings.Default.LOG_DIRECTORY, @"error.json"), rollOnFileSizeLimit: true, retainedFileCountLimit: 5, shared: true)
.Enrich.WithWebApiControllerName()
.Enrich.WithWebApiActionName()
.Enrich.WithWebApiRouteTemplate()
.Enrich.WithWebApiRouteData()
.Enrich.With(new AuthTokenEnricher())
.CreateLogger();
public override void Handle(ExceptionHandlerContext context)
{
if (context != null && context.Exception != null)
{
Log.Error("Unexpected Internal Server Error {Exception}", context.Exception);
}
context.Result = ResponseFactory.CreateErrorResponse(HttpStatusCode.InternalServerError, "Unexpected Internal Server Error", new Error("INTERNAL_SERVER_ERROR", "This request failed because of an unexpected server error."));
}
}
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
//Exception filters
config.Filters.Add(new ExceptionFilter());
config.Services.Replace(typeof(IExceptionHandler), new GlobalExceptionHandler());
// Web API routes
config.MapHttpAttributeRoutes();
}
}
public class ObjectAlreadyExistsException : Exception
{
public ObjectAlreadyExistsException(string message) : base(message)
{
}
public ObjectAlreadyExistsException(string message, Exception inner) : base(message, inner)
{
}
}
现在我提出了一个解决方法,看起来像这样:
[Route("test")]
[HttpGet]
public IHttpActionResult GetTest()
{
try
{
throw new ObjectAlreadyExistsException("test");
}
catch (Exception ex)
{
return CustomExceptionHandler.Handle(ex);
}
}
public class CustomExceptionHandler
{
private static readonly ILogger Log = new LoggerConfiguration()
.WriteTo.File(new CompactJsonFormatter(), Path.Combine(@Properties.Settings.Default.LOG_DIRECTORY, @"error.json"), rollOnFileSizeLimit: true, retainedFileCountLimit: 5, shared: true)
.Enrich.WithWebApiControllerName()
.Enrich.WithWebApiActionName()
.Enrich.WithWebApiRouteTemplate()
.Enrich.WithWebApiRouteData()
.Enrich.With(new AuthTokenEnricher())
.CreateLogger();
public static IHttpActionResult Handle(Exception ex)
{
IHttpActionResult result = null;
if (ex != null)
{
if (ex is ObjectAlreadyExistsException)
{
result = ResponseFactory.CreateErrorResponse(ex.Message, new Error("OBJECT_ALREADY_EXISTS_ERROR", ex.Message));
}
else if (ex is ObjectNotFoundException)
{
result = ResponseFactory.CreateErrorResponse(ex.Message, new Error("OBJECT_NOT_FOUND_ERROR", ex.Message));
}
}
if (result == null)
{
if (ex != null)
{
Log.Error("Unexpected Internal Server Error {Exception}", ex);
}
result = ResponseFactory.CreateErrorResponse(HttpStatusCode.InternalServerError, "Unexpected Internal Server Error", new Error("INTERNAL_SERVER_ERROR", "This request failed because of an unexpected server error."));
}
return result;
}
}
我将不胜感激任何想法如何调试此或任何建议来解决它.
最佳答案 你可以尝试从IHttpActionResult继承并使用它作为从GlobalExceptionHandler返回异常
private class ErrorMessageResult : IHttpActionResult
{
private readonly HttpResponseMessage _httpResponseMessage;
private HttpRequestMessage _request;
public ErrorMessageResult(HttpRequestMessage request, HttpResponseMessage httpResponseMessage)
{
_request = request;
_httpResponseMessage = httpResponseMessage;
}
public Task<HttpResponseMessage> ExecuteAsync(CancellationToken cancellationToken)
{
return Task.FromResult(_httpResponseMessage);
}
}
并称之为,
public override void Handle(ExceptionHandlerContext context)
{
var result = new HttpResponseMessage(HttpStatusCode.InternalServerError)
{
Content = new StringContent("Internal Server Error Occurred"),
ReasonPhrase = "Exception"
};
context.Result = new ErrorMessageResult(context.Request, result);
}
来自GlobalExceptionHandler:ExceptionHandler