爲什麼Windows Azure診斷程序不能可靠地登錄？

Question

我們在使Windows Azure Diagnostics可靠登錄時遇到問題。這看起來很難，我們不明白爲什麼。

這裏是我們的代碼，有時有效，有時不能：

public class WorkerRole : RoleEntryPoint 
{ 
    public override void Run() 
    { 
     Trace.WriteLine("Run() beginning.", LogLevel.Information.ToString()); 

     try 
     { 
      var logic = new WorkerAgent(); 
      logic.Go(false); 
     } 
     catch (Exception err) 
     { 
      Trace.WriteLine(err.ToString(), LogLevel.Critical.ToString()); 

      Run(); 
     } 
    } 

    public override bool OnStart() 
    { 
     // Initialize our Cloud Storage Configuration. 
     AzureStorageObject.Initialize(AzureConfigurationLocation.AzureProjectConfiguration); 

     // Initialize Azure Diagnostics 

     try 
     { 
      //get the storage account using the default Diag connection string 
      var cs = CloudStorageAccount.FromConfigurationSetting("Microsoft.WindowsAzure.Plugins.Diagnostics.ConnectionString"); 

      //get the diag manager 
      var dm = cs.CreateRoleInstanceDiagnosticManager(RoleEnvironment.DeploymentId, 
                  RoleEnvironment.CurrentRoleInstance.Role.Name, 
                  RoleEnvironment.CurrentRoleInstance.Id); 

      //get the current configuration but if that failed, get the values from config file 
      var dc = dm.GetCurrentConfiguration() ?? DiagnosticMonitor.GetDefaultInitialConfiguration(); 

      //Windows Azure Logs 
      dc.Logs.BufferQuotaInMB = 25; 
      dc.Logs.ScheduledTransferLogLevelFilter = LogLevel.Verbose; 
      dc.Logs.ScheduledTransferPeriod = TimeSpan.FromMinutes(1); 

      //Windows Event Logs 
      dc.WindowsEventLog.BufferQuotaInMB = 25; 
      dc.WindowsEventLog.DataSources.Add("System!*"); 
      dc.WindowsEventLog.DataSources.Add("Application!*"); 
      dc.WindowsEventLog.ScheduledTransferPeriod = TimeSpan.FromMinutes(1); 

      ////Performance Counters 
      //dc.PerformanceCounters.BufferQuotaInMB = 25; 
      //var perfConfig = new PerformanceCounterConfiguration 
      //      { 
      //       CounterSpecifier = @"\Processor(_Total)\% Processor Time", 
      //       SampleRate = TimeSpan.FromSeconds(60) 
      //      }; 
      //dc.PerformanceCounters.DataSources.Add(perfConfig); 
      //dc.PerformanceCounters.ScheduledTransferPeriod = TimeSpan.FromMinutes(1); 

      //Failed Request Logs 
      dc.Directories.BufferQuotaInMB = 25; 
      dc.Directories.ScheduledTransferPeriod = TimeSpan.FromMinutes(1); 

      ////Infrastructure Logs 
      //dc.DiagnosticInfrastructureLogs.BufferQuotaInMB = 25; 
      //dc.DiagnosticInfrastructureLogs.ScheduledTransferLogLevelFilter = LogLevel.Verbose; 
      //dc.DiagnosticInfrastructureLogs.ScheduledTransferPeriod = TimeSpan.FromMinutes(1); 

      //Crash Dumps 
      CrashDumps.EnableCollection(true); 

      //overall quota; must be larger than the sum of all items 
      dc.OverallQuotaInMB = 5000; 

      //save the configuration 
      dm.SetCurrentConfiguration(dc); 
     } 
     catch (Exception ex) 
     { 
      Trace.Write(ex.Message, LogLevel.Critical.ToString()); 
     } 

     // give logging time to register itself and load up. 
     Thread.Sleep(10000); 

     Trace.WriteLine("Completed diagnostics initialization.", LogLevel.Information.ToString()); 

     return base.OnStart(); 
    } 
} 

請注意，我們AzureStorageObject.Initialize方法取代了標準CloudStorageAccount.SetConfigurationSettingPublisher方法。

使用此代碼絕對沒有更改代碼或配置的變化，我們可以在模擬器中一遍又一遍又一遍運行或以上，並一遍又一遍地部署它同樣不可靠的結果到Azure。請注意，什麼是應該發生的是1）設置WAD 2）睡眠10秒給它的時間來完成（我是真的抓住了救命稻草，當我加入這個）3）日誌WAD初始化完成4）我們日誌Run()被稱爲然後我們去做所有的工作（WorkerAgent有我們的while(true)循環）。有時候這是事情發生的。有時，我們沒有得到3）中記錄的信息，但我們確實在4）中得到了它。有時我們不會在3或4）。同樣，代碼或配置中沒有任何更改，所有這些都指向Azure存儲（而非模擬器存儲）。

爲什麼沒有這種可靠記錄每次我們打電話Trace.Write時間？

Answer 1

這個問題

TraceSource.TraceEvent() fails logging when Exception message contains non-printable characters

時登錄靜靜地失敗作爲例外的結果，同時記錄被拋出報告的問題。特別是在這種情況下，日誌消息不能被序列化。

這種情況的解決辦法是使用HttpUtility.HtmlEncode它在Azure中登錄前的異常文本編碼。