uriloader/base/nsIURILoader.idl

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsISupports.idl"
   7
   8 interface nsIURIContentListener;
   9 interface nsIURI;
  10 interface nsILoadGroup;
  11 interface nsIProgressEventSink;
  12 interface nsIChannel;
  13 interface nsIRequest;
  14 interface nsIStreamListener;
  15 interface nsIInputStream;
  16 interface nsIInterfaceRequestor;
  17
  18 /**
  19  * The uri dispatcher is responsible for taking uri's, determining
  20  * the content and routing the opened url to the correct content
  21  * handler.
  22  *
  23  * When you encounter a url you want to open, you typically call
  24  * openURI, passing it the content listener for the window the uri is
  25  * originating from. The uri dispatcher opens the url to discover the
  26  * content type. It then gives the content listener first crack at
  27  * handling the content. If it doesn't want it, the dispatcher tries
  28  * to hand it off one of the registered content listeners. This allows
  29  * running applications the chance to jump in and handle the content.
  30  *
  31  * If that also fails, then the uri dispatcher goes to the registry
  32  * looking for the preferred content handler for the content type
  33  * of the uri. The content handler may create an app instance
  34  * or it may hand the contents off to a platform specific plugin
  35  * or helper app. Or it may hand the url off to an OS registered
  36  * application.
  37  */
  38 [scriptable, uuid(8762c4e7-be35-4958-9b81-a05685bb516d)]
  39 interface nsIURILoader : nsISupports
  40 {
  41   /**
  42    * @name Flags for opening URIs.
  43    */
  44   /* @{ */
  45   /**
  46    * Should the content be displayed in a container that prefers the
  47    * content-type, or will any container do.
  48    */
  49   const unsigned long IS_CONTENT_PREFERRED = 1 << 0;
  50   /**
  51    * If this flag is set, only the listener of the specified window context will
  52    * be considered for content handling; if it refuses the load, an error will
  53    * be indicated.
  54    */
  55   const unsigned long DONT_RETARGET        = 1 << 1;
  56   /* @} */
  57
  58   /**
  59    * As applications such as messenger and the browser are instantiated,
  60    * they register content listener's with the uri dispatcher corresponding
  61    * to content windows within that application.
  62    *
  63    * Note to self: we may want to optimize things a bit more by requiring
  64    * the content types the registered content listener cares about.
  65    *
  66    * @param aContentListener
  67    *        The listener to register. This listener must implement
  68    *        nsISupportsWeakReference.
  69    *
  70    * @see the nsIURILoader class description
  71    */
  72   void registerContentListener   (in nsIURIContentListener aContentListener);
  73   void unRegisterContentListener (in nsIURIContentListener aContentListener);
  74
  75   /**
  76    * OpenURI requires the following parameters.....
  77    * @param aChannel
  78    *        The channel that should be opened. This must not be asyncOpen'd yet!
  79    *        If a loadgroup is set on the channel, it will get replaced with a
  80    *        different one.
  81    * @param aFlags
  82    *        Combination (bitwise OR) of the flags specified above. 0 indicates
  83    *        default handling.
  84    * @param aWindowContext
  85    *        If you are running the url from a doc shell or a web shell, this is
  86    *        your window context. If you have a content listener you want to
  87    *        give first crack to, the uri loader needs to be able to get it
  88    *        from the window context. We will also be using the window context
  89    *        to get at the progress event sink interface.
  90    *        <b>Must not be null!</b>
  91    */
  92   void openURI(in nsIChannel aChannel,
  93                in unsigned long aFlags,
  94                in nsIInterfaceRequestor aWindowContext);
  95
  96   /**
  97    * Loads data from a channel. This differs from openURI in that the channel
  98    * may already be opened, and that it returns a stream listener into which the
  99    * caller should pump data. The caller is responsible for opening the channel
 100    * and pumping the channel's data into the returned stream listener.
 101    *
 102    * Note: If the channel already has a loadgroup, it will be replaced with the
 103    * window context's load group, or null if the context doesn't have one.
 104    *
 105    * If the window context's nsIURIContentListener refuses the load immediately
 106    * (e.g. in nsIURIContentListener::onStartURIOpen), this method will return
 107    * NS_ERROR_WONT_HANDLE_CONTENT. At that point, the caller should probably
 108    * cancel the channel if it's already open (this method will not cancel the
 109    * channel).
 110    *
 111    * If flags include DONT_RETARGET, and the content listener refuses the load
 112    * during onStartRequest (e.g. in canHandleContent/isPreferred), then the
 113    * returned stream listener's onStartRequest method will return
 114    * NS_ERROR_WONT_HANDLE_CONTENT.
 115    *
 116    * @param aChannel
 117    *        The channel that should be loaded. The channel may already be
 118    *        opened. It must not be closed (i.e. this must be called before the
 119    *        channel calls onStopRequest on its stream listener).
 120    * @param aFlags
 121    *        Combination (bitwise OR) of the flags specified above. 0 indicates
 122    *        default handling.
 123    * @param aWindowContext
 124    *        If you are running the url from a doc shell or a web shell, this is
 125    *        your window context. If you have a content listener you want to
 126    *        give first crack to, the uri loader needs to be able to get it
 127    *        from the window context. We will also be using the window context
 128    *        to get at the progress event sink interface.
 129    *        <b>Must not be null!</b>
 130    */
 131   nsIStreamListener openChannel(in nsIChannel aChannel,
 132                                 in unsigned long aFlags,
 133                                 in nsIInterfaceRequestor aWindowContext);
 134
 135   /**
 136    * Stops an in progress load
 137    */
 138   void stop(in nsISupports aLoadCookie);
 139 };