NETCore Web API中使用AOP记录异常

Question

我有一个正在运行的Web API项目，我想使用记录器将Web API中的所有控制器记录到文件中。

[HttpGet]
    [Route("")]
    public IActionResult GetAllDocumentTempates()
    {
        try
        {
            var document = _doumentTemplate.GetLiteDocumentReportTemplates().ToList();
            var result = Mapper.Map<IEnumerable<LiteDocumentReportTemplateViewModel>>(document);
            return Ok(result);
        }
        catch (Exception ex)
        {
            String msgInnerExAndStackTrace = string.Format("{0}; Inner Ex: {1};  Stack Trace: {2}", ex.Message, ex.InnerException, ex.StackTrace);
            ExceptionLoggingService.Instance.WriteLog(string.Format("From frmDelivery.ConditionallyPrint():{0}", msgInnerExAndStackTrace));
            return BadRequest();
        }
    }

This is my ExceptionLoggingService.cs:这是处理所有错误并为我记录文件的服务

public class ExceptionLoggingService: ActionFilterAttribute
{
    // </ Singleton code
    // private fields
    private readonly FileStream _fileStream;
    private readonly StreamWriter _streamWriter;
    private static ExceptionLoggingService _instance;
    // public property
    public static ExceptionLoggingService Instance
    {
        get
        {
            return _instance ?? (_instance = new ExceptionLoggingService());
        }
    }
    //private constructor
    private ExceptionLoggingService()
    {
        _fileStream = File.OpenWrite(GetExecutionFolder() + "\\EasyAsFallingOffA.log");
        _streamWriter = new StreamWriter(_fileStream);
    }
    // <!-- Singleton code

    public void WriteLog(string message)
    {
        if (!HHSConsts.Logging) return;
        StringBuilder formattedMessage = new StringBuilder();
        formattedMessage.AppendLine("Date: " + DateTime.Now.ToString());
        formattedMessage.AppendLine("Message: " + message);
        _streamWriter.WriteLine(formattedMessage.ToString());
        _streamWriter.Flush();
    }
    private string GetExecutionFolder()
    {
        return Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);

    }
}

这是我的EasyAsFallingOffA.log文件输出

日期：2018/6/23 12:02:24消息：来自frmDelivery.ConditionallyPrint（）：未将对象引用设置为对象的实例。 内部Ex ：； 堆栈跟踪：位于C：\\ Users \\ BABATUNDE \\ Documents \\ Visual Studio 2017 \\ Projects \\ pcm-netcore \\ ProcessFlowManager.Domain \\ Helpers \\ ModelFactory.cs：行1170处的ProcessFlowManager.Domain.Helpers.ModelFactory.Create（CalendarActivity cal） C：\\ Users \\ BABATUNDE \\ Documents \\ Visual Studio 2017 \\ Projects \\ pcm-netcore \\ ProcessFlowManager.Infrastructure \\ LogicImplementations \\ EfCalendarActivity.cs：Line 54中的ProcessFlowManager.Infrastructure.LogicImplementations.EfCalendarActivities.GetCalendarActivity（Int32 id）在ProcessFlowManager.API上的第54行。 C：\\ Users \\ BABATUNDE \\ Documents \\ Visual Studio 2017 \\ Projects \\ pcm-netcore \\ ProcessFlowManager.API \\ Controllers \\ CalendarController.cs：line 79中的Controllers.CalendarController.GetAllGeneratedDcument（Int32 id）

上面的所有代码一切正常，但是所有这些代码都是使用重言式实现的，因为我在所有尝试和捕获中都进行了重复。 我是AOP的新手，正在寻找一种使用AOP进行此操作的方法，因此我可以在控制器内调用它一次。

Answer 1

经过大量改组，尝试获取我的问题的答案后，我已经成功记录了所有异常，而未使用第三方库，例如PostSharp，Log4File，Spring等。

ActionFilterAttribute，IExceptionFilter

我能够解决此问题，并使用以下代码记录我的企业项目的所有异常

public class LatestErrorHandler : ActionFilterAttribute, IExceptionFilter
{
    private const string FILE_NAME = "Exception.log";
    private const string TRACE_FILE = "TraceLog.log";
    public Type _exceptionType;
    FileStream _fileStream;
    StreamWriter _streamWriter;
    IHostingEnvironment host;
    public LatestErrorHandler(Type exceptionType)
    {
       // _fileStream = File.OpenWrite(host.ContentRootPath + "\\wale.log");
        //_streamWriter = new StreamWriter(_fileStream);
        //_fileStream.Close();
        _exceptionType = exceptionType;
    }


    public override void OnActionExecuting(ActionExecutingContext context)
    {
        base.OnActionExecuting(context);
        using (FileStream fs=new FileStream(TRACE_FILE, FileMode.Append, FileAccess.Write))
        {
            using (BinaryWriter rite=new BinaryWriter(fs))
            {
                if (context.HttpContext.Response==null)
                {
                    string con = "No log";
                    rite.Write(con);
                }
                else
                {
                    Controller exValue = (Controller)context.Controller;
                    ControllerContext control = (ControllerContext)exValue.ControllerContext;
                    ///HttpMethodActionConstraint http = (HttpMethodActionConstraint)control.ActionDescriptor.ActionConstraints.;

                    rite.Write(
                                 "  Date Exception Occurred" + DateTime.Now.ToString() +
                                 "  Route " 
                                 +control.RouteData.DataTokens.Values
                                 +context.RouteData.Routers
                                 //+control.ActionDescriptor.ActionConstraints+ ":"+ http.HttpMethods
                                 + context.RouteData.Values.Keys
                                 + control.ActionDescriptor.ActionName
                                 +context.ActionDescriptor.RouteValues.Values+
                                 "  Parameter"
                                 + context.ActionDescriptor.Parameters 
                                 +context.ActionDescriptor.Properties+
                                 "  Controller" 
                                 + control.ActionDescriptor.ControllerName

                                           );
                }
            }
        }


    }





    public void OnException(ExceptionContext context)
    {
        var cont= context.Exception;
        //var contInner = context.Exception.InnerException;
        using (FileStream fs = new FileStream(FILE_NAME, FileMode.OpenOrCreate, FileAccess.ReadWrite))
        {
            using (BinaryWriter rite = new BinaryWriter(fs))
          {
                // context.Result actionResult = new context.Result();

                if (context.HttpContext.Response == null)
                {
                    string con = "no errroer  ";
                    rite.Write(con);
                }
                else
                {

                    rite.Write(
                        "Date Exception Occurred" + DateTime.Now.ToString() +
                        " Exceptions" + "Message: " + cont.Message +
                        " InnerException" + cont.InnerException +
                        " StackTrace" + cont.StackTrace+
                        "Response" + context.HttpContext.Response.StatusCode
                    );




                }

            }

        }

    }






    public override void OnActionExecuted(ActionExecutedContext context)
    {

        base.OnActionExecuted(context);
        var cont = context.Exception;
        //var contInner = context.Exception.InnerException;
        using (FileStream fs = new FileStream(FILE_NAME, FileMode.Append, FileAccess.Write))
        {
            using (BinaryWriter rite=new BinaryWriter(fs))
            {
                // context.Result actionResult = new context.Result();
               var type =  context.Result.GetType().Name;   //context.Result

                if(type == "BadRequestObjectResult" )
                {

                    BadRequestObjectResult cont2 = (BadRequestObjectResult)context.Result;


                    Exception exValue = (Exception) cont2.Value;
                    if (exValue.InnerException==null)
                    {
                        rite.Write(
                              "\n  Date Exception Occurred  " + DateTime.Now.ToString() +
                              "\n  Exceptions" + "Message: " + cont2.Value +
                             // "\n  InnerException  " + exValue.InnerException +
                              "\n  Message    " + exValue.Message +
                              "\n  StackTrace  " + exValue.StackTrace
                       //"Response" + context.HttpContext.Response.StatusCode
                       );
                    }
                    else
                    {
                        rite.Write(
                               "\n  Date Exception Occurred  " + DateTime.Now.ToString() +
                               "\n  Exceptions" + "Message: " + cont2.Value +
                               "\n  InnerException  " + exValue.InnerException +
                               "\n  Message    " + exValue.Message +
                               "\n  StackTrace  " + exValue.StackTrace
                        //"Response" + context.HttpContext.Response.StatusCode
                        );
                    }


                }






                else
                {
                    // log details without error.





                }

            }

        }

    }



}

在此类中，我使用了面向方面的编程（AOP）来成功地将所有异常记录到我所有控制器中的文件中。

 [LatestErrorHandler(typeof(ExceptionContext))]
//[CustomLoggingAttirbute]
[Produces("application/json")]
[Route("api/Calendar")]
public class CalendarController : Controller
{
      ICalendarActivities calendarActivities;

    IHostingEnvironment IHostingEnvironment;

    string projectFolder = "";
    string fileRootPath = "";

    // private string projectRootFolder;
    public CalendarController(ICalendarActivities _calendarActivities)
    {
        calendarActivities = _calendarActivities;
    }

    [HttpGet]
    [Route("")]

    public IActionResult GetAllCalenderReportList()
    {
        try
        {
            var calendars = calendarActivities.GetCalendarActivities();
            var result = AutoMapper.Mapper.Map<IEnumerable<LiteCalendarViewModel>>(calendars);
            return Ok(result);
        }
        catch (Exception ex)

        {
            //string msginnerexandstacktrace = string.Format("{0}; inner ex: {1};  stack trace: {2}", ex.Message, ex.InnerException, ex.StackTrace);
            //ExceptionLoggingService.Instance.WriteLog(string.Format("from frmdelivery.conditionallyprint():{0}", msginnerexandstacktrace));
            return BadRequest(ex);
        }
    }

这是我的输出

日期发生日期7/2/2018 5:13:18 PM Exceptions消息：System.NullReferenceException：对象引用未设置为对象的实例。 在ProcessFlowManager.Infrastructure的C：\\ Users \\ BABATUNDE \\ Documents \\ Visual Studio 2017 \\ Projects \\ pcm-netcore \\ ProcessFlowManager.Domain \\ Helpers \\ ModelFactory.cs：行1170处的ProcessFlowManager.Domain.Helpers.ModelFactory.Create（CalendarActivity cal） .LogicImplementations.EfCalendarActivities.GetCalendarActivity（Int32 id）在C：\\ Users \\ BABATUNDE \\ Documents \\ Visual Studio 2017 \\ Projects \\ pcm-netcore \\ ProcessFlowManager.Infrastructure \\ LogicImplementations \\ EfCalendarActivities.cs：Line 48在ProcessFlowManager.API.Controllers.CalendarController .GetAllGeneratedDcument（Int32 id）在C：\\ Users \\ BABATUNDE \\ Documents \\ Visual Studio 2017 \\ Projects \\ pcm-netcore \\ ProcessFlowManager.API \\ Controllers \\ CalendarController.cs：line 83 InnerException
消息对象引用未设置为对象的实例。 在C：\\ Users \\ BABATUNDE \\ Documents \\ Visual Studio 2017 \\ Projects \\ pcm-netcore \\ ProcessFlowManager.Domain \\ Helpers \\ ModelFactory.cs：line 1170中的ProcessFlowManager.Domain.Helpers.ModelFactory.Create（CalendarActivity cal）处的StackTrace

Answer 2

您可以使用此链接开始： 使用C＃和PostSharp进行面向方面的编程

或者这： 在方法执行之前和之后的注入行为

第一级 ：

1）使用命名为LoggingAspect的项目添加类

2）继承OnMethodBoundaryAspect

3）so OnEntry，OnSuccess，OnExit，OnException的实现

像下面的代码：

    [PSerializable]
   public class LoggingAspect : OnMethodBoundaryAspect
   {

     public override void OnEntry(MethodExecutionArgs args)
     {
        Console.WriteLine("The {0} method has been entered.", args.Method.Name);
     }

     public override void OnSuccess(MethodExecutionArgs args)
     {
       Console.WriteLine("The {0} method executed successfully.", args.Method.Name);
     }

     public override void OnExit(MethodExecutionArgs args)
     {
        Console.WriteLine("The {0} method has exited.", args.Method.Name);
     }     

     public override void OnException(MethodExecutionArgs args)
     {
        Console.WriteLine("An exception was thrown in {0}.", args.Method.Name);
     }

    }

  static class Program
  {
      [LoggingAspect]
      static void Main()
      {
         Console.WriteLine("Hello, world.");
      }
   }

输出：

     The Main method has been entered.
     Hello, world.
     The Main method executed successfully.
     The Main method has exited.