THRIFT-4841 THTTPTransport relies on activeX component
Client: Delphi
Patch: Jens Geyer

This closes #1778
diff --git a/lib/delphi/src/Thrift.WinHTTP.pas b/lib/delphi/src/Thrift.WinHTTP.pas
new file mode 100644
index 0000000..0d824b6
--- /dev/null
+++ b/lib/delphi/src/Thrift.WinHTTP.pas
@@ -0,0 +1,805 @@
+(*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *)
+unit Thrift.WinHTTP;
+
+{$I Thrift.Defines.inc}
+{$SCOPEDENUMS ON}
+
+// packing according to winhttp.h
+{$IFDEF Win64} {$ALIGN 8} {$ELSE} {$ALIGN 4} {$ENDIF}
+
+interface
+
+uses
+  Windows,
+  Classes,
+  SysUtils,
+  Math,
+  Generics.Collections;
+
+
+type
+  HINTERNET = type Pointer;
+  INTERNET_PORT = type WORD;
+  INTERNET_SCHEME = type Integer;
+  LPLPCWSTR = ^LPCWSTR;
+
+  LPURL_COMPONENTS = ^URL_COMPONENTS;
+  URL_COMPONENTS = record
+    dwStructSize      : DWORD;              // set to SizeOf(URL_COMPONENTS)
+    lpszScheme        : LPWSTR;             // scheme name
+    dwSchemeLength    : DWORD;
+    nScheme           : INTERNET_SCHEME;    // enumerated scheme type
+    lpszHostName      : LPWSTR;             // host name
+    dwHostNameLength  : DWORD;
+    nPort             : INTERNET_PORT;      // port number
+    lpszUserName      : LPWSTR;             // user name
+    dwUserNameLength  : DWORD;
+    lpszPassword      : LPWSTR;             // password
+    dwPasswordLength  : DWORD;
+    lpszUrlPath       : LPWSTR;             // URL-path
+    dwUrlPathLength   : DWORD;
+    lpszExtraInfo     : LPWSTR;             // extra information
+    dwExtraInfoLength : DWORD;
+  end;
+
+  URL_COMPONENTSW = URL_COMPONENTS;
+  LPURL_COMPONENTSW = LPURL_COMPONENTS;
+
+
+function WinHttpCloseHandle( aHandle : HINTERNET) : BOOL;  stdcall;
+
+function WinHttpOpen( const pszAgentW       : LPCWSTR;
+                      const dwAccessType    : DWORD;
+                      const pszProxyW       : LPCWSTR;
+                      const pszProxyBypassW : LPCWSTR;
+                      const dwFlags         : DWORD
+                      ) : HINTERNET;  stdcall;
+
+function WinHttpConnect( const hSession : HINTERNET;
+                         const pswzServerName : LPCWSTR;
+                         const nServerPort : INTERNET_PORT;
+                         const dwReserved : DWORD
+                         ) : HINTERNET;  stdcall;
+
+function WinHttpOpenRequest( const hConnect : HINTERNET;
+                             const pwszVerb, pwszObjectName, pwszVersion, pwszReferrer : LPCWSTR;
+                             const ppwszAcceptTypes : LPLPCWSTR;
+                             const dwFlags : DWORD
+                             ) : HINTERNET;  stdcall;
+
+function WinHttpSetTimeouts( const hRequestOrSession : HINTERNET;
+                             const aResolveTimeout, aConnectTimeout, aSendTimeout, aReceiveTimeout : Int32
+                             ) : BOOL;  stdcall;
+
+function WinHttpAddRequestHeaders( const hRequest : HINTERNET;
+                                   const pwszHeaders : LPCWSTR;
+                                   const dwHeadersLengthInChars : DWORD;
+                                   const dwModifiers : DWORD
+                                   ) : BOOL;  stdcall;
+
+function WinHttpSendRequest( const hRequest : HINTERNET;
+                             const lpszHeaders : LPCWSTR;
+                             const dwHeadersLength : DWORD;
+                             const lpOptional : Pointer;
+                             const dwOptionalLength : DWORD;
+                             const dwTotalLength : DWORD;
+                             const pContext : Pointer
+                             ) : BOOL;  stdcall;
+
+function WinHttpWriteData( const hRequest : HINTERNET;
+                           const pBuf : Pointer;
+                           const dwBytesToWrite : DWORD;
+                           out dwBytesWritten : DWORD
+                           ) : BOOL;  stdcall;
+
+function WinHttpReceiveResponse( const hRequest : HINTERNET; const lpReserved : Pointer) : BOOL;  stdcall;
+
+function WinHttpQueryHeaders( const hRequest     : HINTERNET;
+                              const dwInfoLevel  : DWORD;
+                              const pwszName     : LPCWSTR;
+                              const lpBuffer     : Pointer;
+                              var dwBufferLength : DWORD;
+                              var dwIndex        : DWORD
+                              ) : BOOL;  stdcall;
+
+function WinHttpQueryDataAvailable( const hRequest     : HINTERNET;
+                                    var dwNumberOfBytesAvailable : DWORD
+                                    ) : BOOL;  stdcall;
+
+function WinHttpReadData( const hRequest      : HINTERNET;
+                          const lpBuffer      : Pointer;
+                          const dwBytesToRead : DWORD;
+                          out dwBytesRead     : DWORD
+                          ) : BOOL;  stdcall;
+
+function WinHttpCrackUrl( const pwszUrl : LPCWSTR;
+                          const dwUrlLength : DWORD;
+                          const dwFlags : DWORD;
+                          var urlComponents : URL_COMPONENTS
+                          ) : BOOL;  stdcall;
+
+function WinHttpCreateUrl( const UrlComponents : URL_COMPONENTS;
+                           const dwFlags : DWORD;
+                           const pwszUrl : LPCWSTR;
+                           var pdwUrlLength : DWORD
+                          ) : BOOL;  stdcall;
+
+
+const
+  // WinHttpOpen dwAccessType values
+  WINHTTP_ACCESS_TYPE_DEFAULT_PROXY = 0;
+  WINHTTP_ACCESS_TYPE_NO_PROXY      = 1;
+  WINHTTP_ACCESS_TYPE_NAMED_PROXY   = 3;
+
+  // flags for WinHttpOpen():
+  WINHTTP_FLAG_ASYNC = $10000000;  // want async session, requires WinHttpSetStatusCallback() usage
+
+  // ports
+  INTERNET_DEFAULT_PORT = 0;           // use the protocol-specific default (80 or 443)
+
+  // flags for WinHttpOpenRequest():
+  WINHTTP_FLAG_SECURE                = $00800000;  // use SSL if applicable (HTTPS)
+  WINHTTP_FLAG_ESCAPE_PERCENT        = $00000004;  // if escaping enabled, escape percent as well
+  WINHTTP_FLAG_NULL_CODEPAGE         = $00000008;  // assume all symbols are ASCII, use fast convertion
+  WINHTTP_FLAG_BYPASS_PROXY_CACHE    = $00000100; // add "pragma: no-cache" request header
+  WINHTTP_FLAG_REFRESH               = WINHTTP_FLAG_BYPASS_PROXY_CACHE;
+  WINHTTP_FLAG_ESCAPE_DISABLE        = $00000040;  // disable escaping
+  WINHTTP_FLAG_ESCAPE_DISABLE_QUERY  = $00000080;  // if escaping enabled escape path part, but do not escape query
+
+  // flags for WinHttpSendRequest():
+  WINHTTP_NO_ADDITIONAL_HEADERS   = nil;
+  WINHTTP_NO_REQUEST_DATA         = nil;
+
+  // WinHttpAddRequestHeaders() dwModifiers
+  WINHTTP_ADDREQ_INDEX_MASK = $0000FFFF;
+  WINHTTP_ADDREQ_FLAGS_MASK = $FFFF0000;
+
+  WINHTTP_ADDREQ_FLAG_ADD_IF_NEW                = $10000000;
+  WINHTTP_ADDREQ_FLAG_ADD                       = $20000000;
+  WINHTTP_ADDREQ_FLAG_COALESCE_WITH_COMMA       = $40000000;
+  WINHTTP_ADDREQ_FLAG_COALESCE_WITH_SEMICOLON   = $01000000;
+  WINHTTP_ADDREQ_FLAG_COALESCE                  = WINHTTP_ADDREQ_FLAG_COALESCE_WITH_COMMA;
+  WINHTTP_ADDREQ_FLAG_REPLACE                   = $80000000;
+
+  // URL functions
+  ICU_NO_ENCODE          = $20000000;  // Don't convert unsafe characters to escape sequence
+  ICU_DECODE             = $10000000;  // Convert %XX escape sequences to characters
+  ICU_NO_META            = $08000000;  // Don't convert .. etc. meta path sequences
+  ICU_ENCODE_SPACES_ONLY = $04000000;  // Encode spaces only
+  ICU_BROWSER_MODE       = $02000000;  // Special encode/decode rules for browser
+  ICU_ENCODE_PERCENT     = $00001000;  // Encode any percent (ASCII25)
+
+  ICU_ESCAPE             = $80000000;  // (un)escape URL characters
+  ICU_ESCAPE_AUTHORITY   = $00002000;  // causes InternetCreateUrlA to escape chars in authority components (user, pwd, host)
+  ICU_REJECT_USERPWD     = $00004000;  // rejects usrls whick have username/pwd sections
+
+  INTERNET_SCHEME_HTTP  = INTERNET_SCHEME(1);
+  INTERNET_SCHEME_HTTPS = INTERNET_SCHEME(2);
+
+const
+  WINHTTP_ERROR_BASE                      = 12000;
+  ERROR_WINHTTP_OUT_OF_HANDLES            = WINHTTP_ERROR_BASE + 1;
+  ERROR_WINHTTP_TIMEOUT                   = WINHTTP_ERROR_BASE + 2;
+  ERROR_WINHTTP_INTERNAL_ERROR            = WINHTTP_ERROR_BASE + 4;
+  ERROR_WINHTTP_INVALID_URL               = WINHTTP_ERROR_BASE + 5;
+  ERROR_WINHTTP_UNRECOGNIZED_SCHEME       = WINHTTP_ERROR_BASE + 6;
+  ERROR_WINHTTP_NAME_NOT_RESOLVED         = WINHTTP_ERROR_BASE + 7;
+  ERROR_WINHTTP_INVALID_OPTION            = WINHTTP_ERROR_BASE + 9;
+  ERROR_WINHTTP_OPTION_NOT_SETTABLE       = WINHTTP_ERROR_BASE + 11;
+  ERROR_WINHTTP_SHUTDOWN                  = WINHTTP_ERROR_BASE + 12;
+  ERROR_WINHTTP_LOGIN_FAILURE             = WINHTTP_ERROR_BASE + 15;
+  ERROR_WINHTTP_OPERATION_CANCELLED       = WINHTTP_ERROR_BASE + 17;
+  ERROR_WINHTTP_INCORRECT_HANDLE_TYPE     = WINHTTP_ERROR_BASE + 18;
+  ERROR_WINHTTP_INCORRECT_HANDLE_STATE    = WINHTTP_ERROR_BASE + 19;
+  ERROR_WINHTTP_CANNOT_CONNECT            = WINHTTP_ERROR_BASE + 29;
+  ERROR_WINHTTP_CONNECTION_ERROR          = WINHTTP_ERROR_BASE + 30;
+  ERROR_WINHTTP_RESEND_REQUEST            = WINHTTP_ERROR_BASE + 32;
+  ERROR_WINHTTP_CLIENT_AUTH_CERT_NEEDED   = WINHTTP_ERROR_BASE + 44;
+  ERROR_WINHTTP_CANNOT_CALL_BEFORE_OPEN	  = WINHTTP_ERROR_BASE + 100;
+  ERROR_WINHTTP_CANNOT_CALL_BEFORE_SEND	  = WINHTTP_ERROR_BASE + 101;
+  ERROR_WINHTTP_CANNOT_CALL_AFTER_SEND	  = WINHTTP_ERROR_BASE + 102;
+  ERROR_WINHTTP_CANNOT_CALL_AFTER_OPEN	  = WINHTTP_ERROR_BASE + 103;
+  ERROR_WINHTTP_HEADER_NOT_FOUND          = WINHTTP_ERROR_BASE + 150;
+  ERROR_WINHTTP_INVALID_SERVER_RESPONSE   = WINHTTP_ERROR_BASE + 152;
+  ERROR_WINHTTP_INVALID_HEADER            = WINHTTP_ERROR_BASE + 153;
+  ERROR_WINHTTP_INVALID_QUERY_REQUEST     = WINHTTP_ERROR_BASE + 154;
+  ERROR_WINHTTP_HEADER_ALREADY_EXISTS     = WINHTTP_ERROR_BASE + 155;
+  ERROR_WINHTTP_REDIRECT_FAILED           = WINHTTP_ERROR_BASE + 156;
+  ERROR_WINHTTP_AUTO_PROXY_SERVICE_ERROR  = WINHTTP_ERROR_BASE + 178;
+  ERROR_WINHTTP_BAD_AUTO_PROXY_SCRIPT     = WINHTTP_ERROR_BASE + 166;
+  ERROR_WINHTTP_UNABLE_TO_DOWNLOAD_SCRIPT = WINHTTP_ERROR_BASE + 167;
+  ERROR_WINHTTP_NOT_INITIALIZED           = WINHTTP_ERROR_BASE + 172;
+  ERROR_WINHTTP_SECURE_FAILURE            = WINHTTP_ERROR_BASE + 175;
+
+  // Certificate security errors. Additional information is provided
+  // via the WINHTTP_CALLBACK_STATUS_SECURE_FAILURE callback notification.
+  ERROR_WINHTTP_SECURE_CERT_DATE_INVALID    = WINHTTP_ERROR_BASE + 37;
+  ERROR_WINHTTP_SECURE_CERT_CN_INVALID      = WINHTTP_ERROR_BASE + 38;
+  ERROR_WINHTTP_SECURE_INVALID_CA           = WINHTTP_ERROR_BASE + 45;
+  ERROR_WINHTTP_SECURE_CERT_REV_FAILED      = WINHTTP_ERROR_BASE + 57;
+  ERROR_WINHTTP_SECURE_CHANNEL_ERROR        = WINHTTP_ERROR_BASE + 157;
+  ERROR_WINHTTP_SECURE_INVALID_CERT         = WINHTTP_ERROR_BASE + 169;
+  ERROR_WINHTTP_SECURE_CERT_REVOKED         = WINHTTP_ERROR_BASE + 170;
+  ERROR_WINHTTP_SECURE_CERT_WRONG_USAGE     = WINHTTP_ERROR_BASE + 179;
+
+  ERROR_WINHTTP_AUTODETECTION_FAILED                  = WINHTTP_ERROR_BASE + 180;
+  ERROR_WINHTTP_HEADER_COUNT_EXCEEDED                 = WINHTTP_ERROR_BASE + 181;
+  ERROR_WINHTTP_HEADER_SIZE_OVERFLOW                  = WINHTTP_ERROR_BASE + 182;
+  ERROR_WINHTTP_CHUNKED_ENCODING_HEADER_SIZE_OVERFLOW = WINHTTP_ERROR_BASE + 183;
+  ERROR_WINHTTP_RESPONSE_DRAIN_OVERFLOW               = WINHTTP_ERROR_BASE + 184;
+  ERROR_WINHTTP_CLIENT_CERT_NO_PRIVATE_KEY            = WINHTTP_ERROR_BASE + 185;
+  ERROR_WINHTTP_CLIENT_CERT_NO_ACCESS_PRIVATE_KEY     = WINHTTP_ERROR_BASE + 186;
+
+
+const
+  WINHTTP_THRIFT_DEFAULTS = WINHTTP_FLAG_NULL_CODEPAGE
+                         or WINHTTP_FLAG_BYPASS_PROXY_CACHE
+                         or WINHTTP_FLAG_ESCAPE_DISABLE;
+
+
+type
+  IWinHTTPRequest = interface
+    ['{35C6D9D4-FDCE-42C6-B84C-9294E6FB904C}']
+    function  Handle : HINTERNET;
+    function  AddRequestHeader( const aHeader : string; const addflag : DWORD = WINHTTP_ADDREQ_FLAG_ADD) : Boolean;
+    function  SetTimeouts( const aResolveTimeout, aConnectTimeout, aSendTimeout, aReceiveTimeout : Int32) : Boolean;
+    function  SendRequest( const pBuf : Pointer; const dwBytes : DWORD; const dwExtra : DWORD = 0) : Boolean;
+    function  WriteExtraData( const pBuf : Pointer; const dwBytes : DWORD) : DWORD;
+    function  FlushAndReceiveResponse : Boolean;
+    function  ReadData( const dwRead : DWORD) : TBytes;  overload;
+    function  ReadData( const pBuf : Pointer; const dwRead : DWORD) : DWORD;  overload;
+  end;
+
+  IWinHTTPConnection = interface
+    ['{1C4F78B5-1525-4788-B638-A0E41BCF4D43}']
+    function  Handle : HINTERNET;
+    function  OpenRequest( const secure : Boolean; const aVerb, aObjName, aAcceptTypes : UnicodeString) : IWinHTTPRequest;
+  end;
+
+  IWinHTTPSession = interface
+    ['{B6F8BD98-0605-4A9E-B671-4CB191D74A5E}']
+    function  Handle : HINTERNET;
+    function  Connect( const aHostName : UnicodeString; const aPort : INTERNET_PORT = INTERNET_DEFAULT_PORT) : IWinHTTPConnection;
+    function  SetTimeouts( const aResolveTimeout, aConnectTimeout, aSendTimeout, aReceiveTimeout : Int32) : Boolean;
+  end;
+
+  IWinHTTPUrl = interface
+    ['{78BE977C-4171-4AF5-A250-FD2890205E63}']
+    // url parts getter
+    function  GetScheme : UnicodeString;
+    function  GetNumScheme : INTERNET_SCHEME;
+    function  GetHostName  : UnicodeString;
+    function  GetPort : INTERNET_PORT;
+    function  GetUserName  : UnicodeString;
+    function  GetPassword  : UnicodeString;
+    function  GetUrlPath   : UnicodeString;
+    function  GetExtraInfo : UnicodeString;
+
+    // url parts setter
+    procedure SetScheme( const value : UnicodeString);
+    procedure SetHostName ( const value : UnicodeString);
+    procedure SetPort( const value : INTERNET_PORT);
+    procedure SetUserName( const value : UnicodeString);
+    procedure SetPassword( const value : UnicodeString);
+    procedure SetUrlPath( const value : UnicodeString);
+    procedure SetExtraInfo( const value : UnicodeString);
+
+    // url as a whole
+    function  BuildUrl : UnicodeString;
+    procedure CrackUrl( const value : UnicodeString);
+
+    // url parts
+    property  Scheme    : UnicodeString   read GetScheme    write SetScheme;
+    property  NumScheme : INTERNET_SCHEME read GetNumScheme; // readonly
+    property  HostName  : UnicodeString   read GetHostName  write SetHostName;
+    property  Port      : INTERNET_PORT   read GetPort      write SetPort;
+    property  UserName  : UnicodeString   read GetUserName  write SetUserName;
+    property  Password  : UnicodeString   read GetPassword  write SetPassword;
+    property  UrlPath   : UnicodeString   read GetUrlPath   write SetUrlPath;
+    property  ExtraInfo : UnicodeString   read GetExtraInfo write SetExtraInfo;
+
+    // url as a whole
+    property  CompleteURL : UnicodeString read BuildUrl write CrackUrl;
+  end;
+
+
+
+
+type
+  TWinHTTPHandleObjectImpl = class( TInterfacedObject)
+  strict protected
+    FHandle : HINTERNET;
+    function  Handle : HINTERNET;
+  public
+    constructor Create( const aHandle : HINTERNET);
+    destructor Destroy;  override;
+  end;
+
+
+  TWinHTTPSessionImpl = class( TWinHTTPHandleObjectImpl, IWinHTTPSession)
+  strict protected
+
+    // IWinHTTPSession
+    function  Connect( const aHostName : UnicodeString; const aPort : INTERNET_PORT = INTERNET_DEFAULT_PORT) : IWinHTTPConnection;
+    function  SetTimeouts( const aResolveTimeout, aConnectTimeout, aSendTimeout, aReceiveTimeout : Int32) : Boolean;
+
+  public
+    constructor Create( const aAgent : UnicodeString;
+                        const aAccessType : DWORD          = WINHTTP_ACCESS_TYPE_DEFAULT_PROXY;
+                        const aProxy : UnicodeString       = '';
+                        const aProxyBypass : UnicodeString = '';
+                        const aFlags : DWORD               = 0);
+    destructor Destroy;  override;
+  end;
+
+
+  TWinHTTPConnectionImpl = class( TWinHTTPHandleObjectImpl, IWinHTTPConnection)
+  strict protected
+    FSession : IWinHTTPSession;
+
+    // IWinHTTPConnection
+    function  OpenRequest( const secure : Boolean; const aVerb, aObjName, aAcceptTypes : UnicodeString) : IWinHTTPRequest;
+
+  public
+    constructor Create( const aSession : IWinHTTPSession; const aHostName : UnicodeString; const aPort : INTERNET_PORT);
+    destructor Destroy;  override;
+  end;
+
+
+  TAcceptTypesArray = array of string;
+
+  TWinHTTPRequestImpl = class( TWinHTTPHandleObjectImpl, IWinHTTPRequest)
+  strict protected
+    FConnection : IWinHTTPConnection;
+
+    // IWinHTTPRequest
+    function  AddRequestHeader( const aHeader : string; const addflag : DWORD = WINHTTP_ADDREQ_FLAG_ADD) : Boolean;
+    function  SetTimeouts( const aResolveTimeout, aConnectTimeout, aSendTimeout, aReceiveTimeout : Int32) : Boolean;
+    function  SendRequest( const pBuf : Pointer; const dwBytes : DWORD; const dwExtra : DWORD = 0) : Boolean;
+    function  WriteExtraData( const pBuf : Pointer; const dwBytes : DWORD) : DWORD;
+    function  FlushAndReceiveResponse : Boolean;
+    function  ReadData( const dwRead : DWORD) : TBytes;  overload;
+    function  ReadData( const pBuf : Pointer; const dwRead : DWORD) : DWORD;  overload;
+
+  public
+    constructor Create( const aConnection : IWinHTTPConnection;
+                        const aVerb, aObjName : UnicodeString;
+                        const aVersion : UnicodeString = '';
+                        const aReferrer : UnicodeString = '';
+                        const aAcceptTypes : UnicodeString = '*/*';
+                        const aFlags : DWORD = WINHTTP_THRIFT_DEFAULTS
+                        );
+
+    destructor Destroy;  override;
+  end;
+
+
+  TWinHTTPUrlImpl = class( TInterfacedObject, IWinHTTPUrl)
+  strict private
+    FScheme    : UnicodeString;
+    FNumScheme : INTERNET_SCHEME;
+    FHostName  : UnicodeString;
+    FPort      : INTERNET_PORT;
+    FUserName  : UnicodeString;
+    FPassword  : UnicodeString;
+    FUrlPath   : UnicodeString;
+    FExtraInfo : UnicodeString;
+
+  strict protected
+    // url parts getter
+    function  GetScheme    : UnicodeString;
+    function  GetNumScheme : INTERNET_SCHEME;
+    function  GetHostName  : UnicodeString;
+    function  GetPort      : INTERNET_PORT;
+    function  GetUserName  : UnicodeString;
+    function  GetPassword  : UnicodeString;
+    function  GetUrlPath   : UnicodeString;
+    function  GetExtraInfo : UnicodeString;
+
+    // url parts setter
+    procedure SetScheme(    const value : UnicodeString);
+    procedure SetHostName ( const value : UnicodeString);
+    procedure SetPort(      const value : INTERNET_PORT);
+    procedure SetUserName(  const value : UnicodeString);
+    procedure SetPassword(  const value : UnicodeString);
+    procedure SetUrlPath(   const value : UnicodeString);
+    procedure SetExtraInfo( const value : UnicodeString);
+
+    // url as a whole
+    function  BuildUrl : UnicodeString;
+    procedure CrackUrl( const value : UnicodeString);
+
+  public
+    constructor Create( const aUri : UnicodeString);
+    destructor Destroy;  override;
+  end;
+
+
+  EWinHTTPException = class(Exception);
+
+implementation
+
+const WINHTTP_DLL = 'WinHTTP.dll';
+
+function WinHttpCloseHandle;  stdcall; external WINHTTP_DLL;
+function WinHttpOpen;  stdcall; external WINHTTP_DLL;
+function WinHttpConnect;  stdcall; external WINHTTP_DLL;
+function WinHttpOpenRequest; stdcall; external WINHTTP_DLL;
+function WinHttpSendRequest; stdcall; external WINHTTP_DLL;
+function WinHttpSetTimeouts; stdcall; external WINHTTP_DLL;
+function WinHttpAddRequestHeaders; stdcall; external WINHTTP_DLL;
+function WinHttpWriteData; stdcall; external WINHTTP_DLL;
+function WinHttpReceiveResponse; stdcall; external WINHTTP_DLL;
+function WinHttpQueryHeaders; stdcall; external WINHTTP_DLL;
+function WinHttpQueryDataAvailable; stdcall; external WINHTTP_DLL;
+function WinHttpReadData; stdcall; external WINHTTP_DLL;
+function WinHttpCrackUrl; stdcall; external WINHTTP_DLL;
+function WinHttpCreateUrl; stdcall; external WINHTTP_DLL;
+
+
+{ TWinHTTPHandleObjectImpl }
+
+constructor TWinHTTPHandleObjectImpl.Create( const aHandle : HINTERNET);
+begin
+  inherited Create;
+  FHandle := aHandle;
+
+  if FHandle = nil
+  then raise EWinHTTPException.Create('Invalid handle');
+end;
+
+
+destructor TWinHTTPHandleObjectImpl.Destroy;
+begin
+  try
+    if Assigned(FHandle) then begin
+      WinHttpCloseHandle(FHandle);
+      FHandle := nil;
+    end;
+
+  finally
+    inherited Destroy;
+  end;
+end;
+
+
+function TWinHTTPHandleObjectImpl.Handle : HINTERNET;
+begin
+  result := FHandle;
+end;
+
+
+{ TWinHTTPSessionImpl }
+
+
+constructor TWinHTTPSessionImpl.Create( const aAgent : UnicodeString; const aAccessType : DWORD;
+                                        const aProxy, aProxyBypass : UnicodeString; const aFlags : DWORD);
+var handle : HINTERNET;
+begin
+  handle := WinHttpOpen( PWideChar(aAgent), aAccessType,
+                         PWideChar(Pointer(aProxy)),        // may be nil
+                         PWideChar(Pointer(aProxyBypass)),  // may be nil
+                         aFlags);
+  inherited Create( handle);
+end;
+
+
+destructor TWinHTTPSessionImpl.Destroy;
+begin
+  inherited Destroy;
+  // add code here
+end;
+
+
+function TWinHTTPSessionImpl.Connect( const aHostName : UnicodeString; const aPort : INTERNET_PORT) : IWinHTTPConnection;
+begin
+  result := TWinHTTPConnectionImpl.Create( Self, aHostName, aPort);
+end;
+
+
+function TWinHTTPSessionImpl.SetTimeouts( const aResolveTimeout, aConnectTimeout, aSendTimeout, aReceiveTimeout : Int32) : Boolean;
+begin
+  result := WinHttpSetTimeouts( FHandle, aResolveTimeout, aConnectTimeout, aSendTimeout, aReceiveTimeout);
+end;
+
+
+{ TWinHTTPConnectionImpl }
+
+constructor TWinHTTPConnectionImpl.Create( const aSession : IWinHTTPSession; const aHostName : UnicodeString; const aPort : INTERNET_PORT);
+var handle : HINTERNET;
+begin
+  FSession := aSession;
+  handle   := WinHttpConnect( FSession.Handle, PWideChar(aHostName), aPort, 0);
+  inherited Create( handle);
+end;
+
+
+destructor TWinHTTPConnectionImpl.Destroy;
+begin
+  inherited Destroy;
+  FSession := nil;
+end;
+
+
+function TWinHTTPConnectionImpl.OpenRequest( const secure : Boolean; const aVerb, aObjName, aAcceptTypes : UnicodeString) : IWinHTTPRequest;
+var dwFlags : DWORD;
+begin
+  dwFlags := WINHTTP_THRIFT_DEFAULTS;
+  if secure
+  then dwFlags := dwFlags or WINHTTP_FLAG_SECURE
+  else dwFlags := dwFlags and not WINHTTP_FLAG_SECURE;
+
+  result := TWinHTTPRequestImpl.Create( Self, aVerb, aObjName, '', '', aAcceptTypes, dwFlags);
+end;
+
+
+{ TWinHTTPRequestImpl }
+
+constructor TWinHTTPRequestImpl.Create( const aConnection : IWinHTTPConnection;
+                                        const aVerb, aObjName, aVersion, aReferrer : UnicodeString;
+                                        const aAcceptTypes : UnicodeString;
+                                        const aFlags : DWORD
+                                        );
+var handle : HINTERNET;
+    accept : array[0..1] of PWideChar;
+begin
+  FConnection := aConnection;
+
+  accept[0] := PWideChar(aAcceptTypes);
+  accept[1] := nil;
+
+  handle      := WinHttpOpenRequest( FConnection.Handle,
+                                     PWideChar(UpperCase(aVerb)),
+                                     PWideChar(aObjName),
+                                     PWideChar(aVersion),
+                                     PWideChar(aReferrer),
+                                     @accept,
+                                     aFlags);
+  inherited Create( handle);
+end;
+
+
+destructor TWinHTTPRequestImpl.Destroy;
+begin
+  inherited Destroy;
+  FConnection := nil;
+end;
+
+
+function TWinHTTPRequestImpl.SetTimeouts( const aResolveTimeout, aConnectTimeout, aSendTimeout, aReceiveTimeout : Int32) : Boolean;
+begin
+  result := WinHttpSetTimeouts( FHandle, aResolveTimeout, aConnectTimeout, aSendTimeout, aReceiveTimeout);
+end;
+
+
+function TWinHTTPRequestImpl.AddRequestHeader( const aHeader : string; const addflag : DWORD) : Boolean;
+begin
+  result := WinHttpAddRequestHeaders( FHandle, PWideChar(aHeader), DWORD(-1), addflag);
+end;
+
+
+function TWinHTTPRequestImpl.SendRequest( const pBuf : Pointer; const dwBytes, dwExtra : DWORD) : Boolean;
+begin
+  result := WinHttpSendRequest( FHandle,
+                                WINHTTP_NO_ADDITIONAL_HEADERS, 0,
+                                pBuf, dwBytes,      // number of bytes in pBuf
+                                dwBytes + dwExtra,  // becomes the Content-Length
+                                nil);               // context for async operations
+end;
+
+
+function TWinHTTPRequestImpl.WriteExtraData( const pBuf : Pointer; const dwBytes : DWORD) : DWORD;
+begin
+  if not WinHttpWriteData( FHandle, pBuf, dwBytes, result)
+  then result := 0;
+end;
+
+
+function TWinHTTPRequestImpl.FlushAndReceiveResponse : Boolean;
+begin
+  result := WinHttpReceiveResponse( FHandle, nil);
+end;
+
+
+function TWinHTTPRequestImpl.ReadData( const dwRead : DWORD) : TBytes;
+var dwAvailable, dwReceived : DWORD;
+begin
+  if WinHttpQueryDataAvailable( FHandle, dwAvailable)
+  then dwAvailable := Min( dwRead, dwAvailable)
+  else dwAvailable := 0;
+
+  SetLength( result, dwAvailable);
+  if dwAvailable = 0 then Exit;
+
+  if WinHttpReadData( FHandle, @result[0], Length(result), dwReceived)
+  then SetLength( result, dwReceived)
+  else SetLength( result, 0);
+end;
+
+
+function TWinHTTPRequestImpl.ReadData( const pBuf : Pointer; const dwRead : DWORD) : DWORD;
+var dwAvailable : DWORD;
+begin
+  if WinHttpQueryDataAvailable( FHandle, dwAvailable)
+  then dwAvailable := Min( dwRead, dwAvailable)
+  else dwAvailable := 0;
+
+  if (dwAvailable = 0)
+  or not WinHttpReadData( FHandle, pBuf, dwAvailable, result)
+  then result := 0;
+end;
+
+
+{ TWinHTTPUrlImpl }
+
+constructor TWinHTTPUrlImpl.Create(const aUri: UnicodeString);
+begin
+  inherited Create;
+  CrackUrl( aUri)
+end;
+
+
+destructor TWinHTTPUrlImpl.Destroy;
+begin
+  inherited Destroy;
+end;
+
+
+procedure TWinHTTPUrlImpl.CrackURL( const value : UnicodeString);
+const FLAGS = 0; // no special operations, leave components as-is
+var components : URL_COMPONENTS;
+begin
+  FillChar(components, SizeOf(components), 0);
+  components.dwStructSize := SizeOf(components);
+
+  if value <> '' then begin
+    { For the WinHttpCrackUrl function, [...] if the pointer member is NULL but the
+      length member is not zero, both the pointer and length members are returned. }
+    components.dwSchemeLength    := DWORD(-1);
+    components.dwHostNameLength  := DWORD(-1);
+    components.dwUserNameLength  := DWORD(-1);
+    components.dwPasswordLength  := DWORD(-1);
+    components.dwUrlPathLength   := DWORD(-1);
+    components.dwExtraInfoLength := DWORD(-1);
+
+    WinHttpCrackUrl( PWideChar(value), Length(value), FLAGS, components);
+  end;
+
+  FNumScheme := components.nScheme;
+  FPort      := components.nPort;
+  SetString( FScheme,    components.lpszScheme,    components.dwSchemeLength);
+  SetString( FHostName,  components.lpszHostName,  components.dwHostNameLength);
+  SetString( FUserName,  components.lpszUserName,  components.dwUserNameLength);
+  SetString( FPassword,  components.lpszPassword,  components.dwPasswordLength);
+  SetString( FUrlPath,   components.lpszUrlPath,   components.dwUrlPathLength);
+  SetString( FExtraInfo, components.lpszExtraInfo, components.dwExtraInfoLength);
+end;
+
+
+function TWinHTTPUrlImpl.BuildUrl : UnicodeString;
+const FLAGS = 0; // no special operations, leave components as-is
+var components : URL_COMPONENTS;
+    dwChars : DWORD;
+begin
+  FillChar(components, SizeOf(components), 0);
+  components.dwStructSize      := SizeOf(components);
+  components.lpszScheme        := PWideChar(FScheme);
+  components.dwSchemeLength    := Length(FScheme);
+  components.lpszHostName      := PWideChar(FHostName);
+  components.dwHostNameLength  := Length(FHostName);
+  components.nPort             := FPort;
+  components.lpszUserName      := PWideChar(FUserName);
+  components.dwUserNameLength  := Length(FUserName);
+  components.lpszPassword      := PWideChar(FPassword);
+  components.dwPasswordLength  := Length(FPassword);
+  components.lpszUrlPath       := PWideChar(FUrlPath);
+  components.dwUrlPathLength   := Length(FUrlPath);
+  components.lpszExtraInfo     := PWideChar(FExtraInfo);
+  components.dwExtraInfoLength := Length(FExtraInfo);
+
+  WinHttpCreateUrl( components, FLAGS, nil, dwChars);
+  if dwChars = 0
+  then result := ''
+  else begin
+    SetLength( result, dwChars + 1);
+    WinHttpCreateUrl( components, FLAGS, @result[1], dwChars);
+    SetLength( result, dwChars);  // cut off terminating #0
+  end;
+end;
+
+
+function TWinHTTPUrlImpl.GetExtraInfo: UnicodeString;
+begin
+  result := FExtraInfo;
+end;
+
+function TWinHTTPUrlImpl.GetHostName: UnicodeString;
+begin
+  result := FHostName;
+end;
+
+function TWinHTTPUrlImpl.GetNumScheme: INTERNET_SCHEME;
+begin
+  result := FNumScheme;
+end;
+
+function TWinHTTPUrlImpl.GetPassword: UnicodeString;
+begin
+  result := FPassword;
+end;
+
+function TWinHTTPUrlImpl.GetPort: INTERNET_PORT;
+begin
+  result := FPort;
+end;
+
+function TWinHTTPUrlImpl.GetScheme: UnicodeString;
+begin
+  result := FScheme;
+end;
+
+function TWinHTTPUrlImpl.GetUrlPath: UnicodeString;
+begin
+  result := FUrlPath;
+end;
+
+function TWinHTTPUrlImpl.GetUserName: UnicodeString;
+begin
+  result := FUserName;
+end;
+
+procedure TWinHTTPUrlImpl.SetExtraInfo(const value: UnicodeString);
+begin
+  FExtraInfo := value;
+end;
+
+procedure TWinHTTPUrlImpl.SetHostName(const value: UnicodeString);
+begin
+  FHostName := value;
+end;
+
+procedure TWinHTTPUrlImpl.SetPassword(const value: UnicodeString);
+begin
+  FPassword := value;
+end;
+
+procedure TWinHTTPUrlImpl.SetPort(const value: INTERNET_PORT);
+begin
+  FPort := value;
+end;
+
+procedure TWinHTTPUrlImpl.SetScheme(const value: UnicodeString);
+begin
+  FScheme := value;
+end;
+
+procedure TWinHTTPUrlImpl.SetUrlPath(const value: UnicodeString);
+begin
+  FUrlPath := value;
+end;
+
+procedure TWinHTTPUrlImpl.SetUserName(const value: UnicodeString);
+begin
+  FUserName := value;
+end;
+
+
+end.
+