fiddler 插件开发二

本篇主要讲解Fildder插件开发中的涉及到的主要接口与类。

1.IFiddlerExtension 接口

如果要开发的自定义插件有UI界面，则需要实现IFiddlerExtension 接口。你程序集中的实现了IFiddlerExtension接口的公有类(public class)将会在Fiddler启动时加载。

public interface IFiddlerExtension
    {
      // Called when Fiddler User Interface is fully available
      void OnLoad();

      // Called when Fiddler is shutting down
      void OnBeforeUnload();
    }

• OnLoad 方法将会在Fiddler加载完成并且她的UI完全可用时调用，在这个方法中，你可以安全地添加菜单项，选项卡页或者其他UI元素到Fiddler UI。
• OnBeforeUnload 方法将会在Fiddler 关闭和卸载所有插件时执行。

2.IAutoTamper 接口

IAutoTamper 接口继承了IFiddlerExtension接口，所有实现了IAutoTamper 接口的插件将会在每一个http/https 请求或响应时被调用，所以可以用来劫持或修改http/https 请求响应数据。

注意：这个接口的方法是在后台被调用，非UI线程，如果想要更新UI，可以使用Invoke 或者 BeginInvoke 方法来更新UI。IAutoTamper 的所有方法可能会在OnLoad事件之前就执行。

public interface IAutoTamper : IFiddlerExtension
{
  // Called before the user can edit a request using the Fiddler Inspectors
  void AutoTamperRequestBefore(Session oSession);

  // Called after the user has had the chance to edit the request using the Fiddler Inspectors, but before the request is sent
  void AutoTamperRequestAfter(Session oSession);

  // Called before the user can edit a response using the Fiddler Inspectors, unless streaming.
  void AutoTamperResponseBefore(Session oSession);

  // Called after the user edited a response using the Fiddler Inspectors.  Not called when streaming.
  void AutoTamperResponseAfter(Session oSession);

  // Called Fiddler returns a self-generated HTTP error (for instance DNS lookup failed, etc)
  void OnBeforeReturningError(Session oSession);
}

3.IAutoTamper2 接口

所有实现了IAutoTamper2 接口（继承自IAutoTamper接口)的扩展将会在响应头(Response Headers)可用时被调用。

/// <summary>
/// Interface for AutoTamper extensions that want to "peek" at response headers
/// </summary>
public interface IAutoTamper2 : IAutoTamper
{
     /// <summary>
     /// Called when the response headers become available
     /// </summary>
     /// <param name="oSession">The Session object for which the response headers are available</param>
    void OnPeekAtResponseHeaders(Session oSession);
}

4.IAutoTamper3 接口

所有实现了IAutoTamper3接口(继承自IAutoTamper2接口)的扩展将会在请求头(Request Headers)可用时被调用。

/// <summary>
/// Interface for AutoTamper extensions that want to "peek" at request headers
/// </summary>
public interface IAutoTamper3 : IAutoTamper2
{
    /// <summary>
    /// Called when the request headers become available
    /// </summary>
    /// <param name="oSession">The Session object for which the request headers are available</param>
    void OnPeekAtRequestHeaders(Session oSession);
}

5.IHandleExecAction接口

所有实现了IHandleExecAction接口的扩展将在用户执行QuickExec命令时被调用。OnExecAction方法中返回 true 表示命令执行成功，不用再处理其他Action。

public interface IHandleExecAction
{
  // return TRUE if handled.
  bool OnExecAction(string sCommand);
}

例如：

public bool OnExecAction(string sCommand)
{
    if (sCommand == "clearcache")
    {
        //检测到用户在quickexec中输入的命令是clearcache时，调用Fiddler的清缓存方法
        FiddlerApplication.UI.actClearWinINETCache();
        return true;  //表示命令处理成功，不用继续其他的处理
    }
    return false;  //表示命令没有被处理，允许其他 ExecAction handlers继续处理
}

6.参考资料

http://www.fiddlerbook.com/Fiddler/dev/IFiddlerExtension.asp