Health Monitoring - ASP.NET 2.0

Nas versões anteriores do ASP.NET tínhamos algumas funcionalidades/serviços que nos permitiam monitorar a vida de uma aplicação ASP.NET. Podemos considerar como estes serviços os Traces e os contadores de performance.

por Israel Aéce

using System.Web.Management;

public class CodeEvent : WebBaseEvent
{
    private static readonly int _eventCode = WebEventCodes.WebExtendedBase + 1;

    public CodeEvent(string msg, object eventSource, int eventCode)
        : base(msg, eventSource, CodeEvent._eventCode) {}

    public CodeEvent(string msg, object eventSource, int eventCode, int eventDetails)
        : base(msg, eventSource, CodeEvent._eventCode, eventDetails) {}
}

Imports System.Web.Management

Public Class CodeEvent

    Inherits WebBaseEvent

    Private Shared ReadOnly _eventCode As Integer = WebEventCodes.WebExtendedBase + 1

    Public Sub New(ByVal msg As String, _
        ByVal eventSource As Object, _
        ByVal eventCode As Integer)

        MyBase.New(msg, eventSource, CodeEvent._eventCode)
    End Sub

    Public Sub New(ByVal msg As String, _
        ByVal eventSource As Object, _
        ByVal eventCode As Integer, _
        ByVal eventDetails As Integer)

        MyBase.New(msg, eventSource, CodeEvent._eventCode, eventDetails)
    End Sub

End Class

using System.IO;
using System.Web.Management;

public class TextEventProvider : WebEventProvider
{
    private string _providerName = "TextEventProvider";
    private string _path = string.Empty;

    public override void Initialize(string name, 
        System.Collections.Specialized.NameValueCollection config)
    {
        if (string.IsNullOrEmpty(config["path"]))
            throw new ArgumentException("Caminho inválido/inexistente.");

        this._path = config["path"];
        base.Initialize(name, config);
    }

    public override void ProcessEvent(WebBaseEvent raisedEvent)
    {
        if (raisedEvent is CodeEvent)
        {
            StreamWriter sw = File.AppendText(this._path);
            sw.WriteLine(
                string.Format("{0}\t{1}\t{2}\t{3}\t",
                    raisedEvent.EventCode,
                    raisedEvent.EventID,
                    raisedEvent.EventTime,
                    raisedEvent.Message));
            sw.Close();
        }
    }

    public override void Shutdown(){}
    public override void Flush(){}
}

Imports System.IO
Imports System.Web.Management

Public Class TextEventProvider

    Inherits WebEventProvider

    Private _providerName As String = "TextEventProvider"
    Private _path As String = String.Empty

    Public Overrides Sub Initialize(ByVal name As String, _
        ByVal config As System.Collections.Specialized.NameValueCollection)

        If String.IsNullOrEmpty(config("path")) Then
            Throw New ArgumentException("Caminho inválido/inexistente.")
        End If

        Me._path = config("path")
        MyBase.Initialize(name, config)
    End Sub

    Public Overrides Sub ProcessEvent(ByVal raisedEvent As _
        System.Web.Management.WebBaseEvent)

        If (TypeOf raisedEvent Is CodeEvent) Then
            Dim sw As StreamWriter = File.AppendText(Me._path)
            sw.WriteLine( _
                String.Format("{0}\t{1}\t{2}\t{3}\t", _
                    raisedEvent.EventCode, _
                    raisedEvent.EventID, _
                    raisedEvent.EventTime, _
                    raisedEvent.Message))
            sw.Close()
        End If
    End Sub

    Public Overrides Sub Flush()
    End Sub

    Public Overrides Sub Shutdown()
    End Sub

End Class

<system.web>
  <healthMonitoring enabled="true">
    <providers>
      <add 
          name="TextEventProvider" 
          type="TextEventProvider" 
          path="C:\EventLog.txt"/>
    </providers>
    <eventMappings>
      <add 
          name="Code Event" 
          type="CodeEvent"/>
    </eventMappings>
    <rules>
      <add 
          name="Text Event Rule" 
          eventName="Code Event" 
          provider="TextEventProvider" 
          profile="Default" 
          minInterval="00:00:00"/>
    </rules>
  </healthMonitoring>
</system.web>

try
{
    int i = 0;
    int resultado = 10 / i;
}
catch (DivideByZeroException ex)
{
    CodeEvent codeEvent = new CodeEvent("Divisão por zero.", sender, 0);
    codeEvent.Raise();
}

Try
    Dim i As Integer = 0
    Dim resultado As Integer = 10 / i
Catch(ex As DivideByZeroException)
    Dim codeEvent As New CodeEvent("Divisão por zero.", sender, 0)
    codeEvent.Raise()
End Try