netwerk/base/public/nsITraceableChannel.idl

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is Mozilla.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Jan Wrobel <wrobel@blues.ath.cx>
  19  * Portions created by the Initial Developer are Copyright (C) 2008
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Jan Odvarko <odvarko@gmail.com>
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either the GNU General Public License Version 2 or later (the "GPL"), or
  27  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  28  * in which case the provisions of the GPL or the LGPL are applicable instead
  29  * of those above. If you wish to allow use of your version of this file only
  30  * under the terms of either the GPL or the LGPL, and not to allow others to
  31  * use your version of this file under the terms of the MPL, indicate your
  32  * decision by deleting the provisions above and replace them with the notice
  33  * and other provisions required by the GPL or the LGPL. If you do not delete
  34  * the provisions above, a recipient may use your version of this file under
  35  * the terms of any one of the MPL, the GPL or the LGPL.
  36  *
  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #include "nsISupports.idl"
  40
  41 interface nsIStreamListener;
  42
  43 /**
  44  * A channel implementing this interface allows one to intercept its data by
  45  * inserting intermediate stream listeners.
  46  */
  47 [scriptable, uuid(68167b0b-ef34-4d79-a09a-8045f7c5140e)]
  48 interface nsITraceableChannel : nsISupports
  49 {
  50     /*
  51      * Replace the channel's listener with a new one, and return the listener
  52      * the channel used to have. The new listener intercepts OnStartRequest,
  53      * OnDataAvailable and OnStopRequest calls and must pass them to
  54      * the original listener after examination. If multiple callers replace
  55      * the channel's listener, a chain of listeners is created.
  56      * The caller of setNewListener has no way to control at which place
  57      * in the chain its listener is placed.
  58      *
  59      * Note: The caller of setNewListener must not delay passing
  60      * OnStartRequest to the original listener.
  61      *
  62      * Note2: A channel may restrict when the listener can be replaced.
  63      * It is not recommended to allow listener replacement after OnStartRequest
  64      * has been called.
  65      */
  66     nsIStreamListener setNewListener(in nsIStreamListener aListener);
  67 };