multithreading - Indy 的全局、线程安全、cookie 管理器

Question

我的 Delphi 2010 应用程序使用多线程上传内容，上传的数据被发布到需要登录的 PHP/Web 应用程序，因此我需要使用共享/全局 cookie 管理器(我正在使用 Indy10 修订版 4743 ) 因为 TIdCookieManager 不是线程安全的:(

此外，服务器端 session ID 每 5 分钟自动重新生成一次，因此我必须保持全局和本地 cookie 管理器同步。

我的代码如下所示:

TUploadThread = class(TThread)
// ...

var
   GlobalCookieManager : TIdCookieManager;

procedure TUploadThread.Upload(FileName : String);
var
   IdHTTP           : TIdHTTP;
   TheSSL           : TIdSSLIOHandlerSocketOpenSSL;
   TheCompressor    : TIdCompressorZLib;
   TheCookieManager : TIdCookieManager;
   AStream          : TIdMultipartFormDataStream;
begin
     ACookieManager := TIdCookieManager.Create(IdHTTP);

     // Automatically sync cookies between local & global Cookie managers
     @TheCookieManager.OnNewCookie := pPointer(Cardinal(pPointer( procedure(ASender : TObject; ACookie : TIdCookie; var VAccept : Boolean)
     begin
          OmniLock.Acquire;
          try
             GlobalCookieManager.CookieCollection.AddCookie(ACookie, TIdHTTP(TIdCookieManager(ASender).Owner).URL{IdHTTP.URL});
          finally
                  OmniLock.Release;
          end;    // try/finally

          VAccept := True;
     end )^ ) + $0C)^;
     // ======================================== //


     IdHTTP         := TIdHTTP.Create(nil);
     with IdHTTP do
     begin
          HTTPOptions     := [hoForceEncodeParams, hoNoParseMetaHTTPEquiv];
          AllowCookies    := True;
          HandleRedirects := True;
          ProtocolVersion := pv1_1;

          IOHandler       := TheSSL;
          Compressor      := TheCompressor;
          CookieManager   := TheCookieManager;
     end;    // with

     OmniLock.Acquire;
     try
        // Load login info/cookies
        TheCookieManager.CookieCollection.AddCookies(GlobalCookieManager.CookieCollection);
     finally
            OmniLock.Release;
     end;    // try/finally

     AStream         := TIdMultipartFormDataStream.Create;

     with Stream.AddFile('file_name', FileName, 'application/octet-stream') do
     begin
          HeaderCharset  := 'utf-8';
          HeaderEncoding := '8';
     end;    // with

     IdHTTP.Post('https://www.domain.com/post.php', AStream);
     AStream.Free;
end;

但是这不起作用!我在调用 AddCookies() 时遇到此异常

Project MyEXE.exe raised exception class EAccessViolation with message 'Access violation at address 00000000. Read of address 00000000'.

我也尝试过使用 allocate()，即。

 TheCookieManager.CookieCollection.Assign(GlobalCookieManager.CookieCollection);

但我仍然遇到同样的异常，通常在这里:

 TIdCookieManager.GenerateClientCookies()

有人知道如何解决这个问题吗？

Answer 1

不要对 OnNewCookie 事件使用匿名过程。使用普通的类方法代替:

procedure TUploadThread.NewCookie(ASender: TObject; ACookie : TIdCookie; var VAccept : Boolean);
var
  LCookie: TIdCookie;
begin
  LCookie := TIdCookieClass(ACookie.ClassType).Create;
  LCookie.Assign(ACookie);
  OmniLock.Acquire; 
  try 
    GlobalCookieManager.CookieCollection.AddCookie(LCookie, TIdHTTP(TIdCookieManager(ASender).Owner).URL); 
  finally 
    OmniLock.Release; 
  end;
  VAccept := True;
end;

或者:

procedure TUploadThread.NewCookie(ASender: TObject; ACookie : TIdCookie; var VAccept : Boolean);
begin
  OmniLock.Acquire; 
  try 
    GlobalCookieManager.CookieCollection.AddServerCookie(ACookie.ServerCookie, TIdHTTP(TIdCookieManager(ASender).Owner).URL); 
  finally 
    OmniLock.Release; 
  end;
  VAccept := True;
end;

然后像这样使用它:

procedure TUploadThread.Upload(FileName : String); 
var 
  IdHTTP           : TIdHTTP; 
  TheSSL           : TIdSSLIOHandlerSocketOpenSSL; 
  TheCompressor    : TIdCompressorZLib; 
  TheCookieManager : TIdCookieManager; 
  TheStream        : TIdMultipartFormDataStream; 
begin 
  IdHTTP := TIdHTTP.Create(nil); 
  try
    ...
    TheCookieManager := TIdCookieManager.Create(IdHTTP); 
    TheCookieManager.OnNewCookie := NewCookie;

    with IdHTTP do 
    begin 
      HTTPOptions     := [hoForceEncodeParams, hoNoParseMetaHTTPEquiv]; 
      AllowCookies    := True; 
      HandleRedirects := True; 
      ProtocolVersion := pv1_1; 

      IOHandler       := TheSSL; 
      Compressor      := TheCompressor; 
      CookieManager   := TheCookieManager; 
    end;    // with 

    OmniLock.Acquire; 
    try 
      // Load login info/cookies 
      TheCookieManager.CookieCollection.AddCookies(GlobalCookieManager.CookieCollection); 
    finally 
      OmniLock.Release; 
    end;

    TheStream := TIdMultipartFormDataStream.Create; 
    try
      with TheStream.AddFile('file_name', FileName, 'application/octet-stream') do 
      begin 
        HeaderCharset  := 'utf-8'; 
        HeaderEncoding := '8'; 
      end;

      IdHTTP.Post('https://www.domain.com/post.php', TheStream); 
    finally
      TheStream.Free; 
    end;
  finally
    IdHTTP.Free;
  end;
end;