ios/web/net/request_group_util.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef IOS_WEB_NET_REQUEST_GROUP_UTIL_H_
   6 #define IOS_WEB_NET_REQUEST_GROUP_UTIL_H_
   7
   8 @class NSString;
   9 @class NSURL;
  10 @class NSURLRequest;
  11
  12 // Request group IDs are internally used by the web layer to associate network
  13 // requests to RequestTracker instances, and in turn, to WebState instances.
  14 // The ID can be added to the user-agent string by UIWebView in most cases and
  15 // then extracted by the network layer.
  16 // However, when using non-standard schemes, UIWebView does not add the
  17 // "User-Agent" HTTP header to the requests. The workaround for this case is to
  18 // add the ID directly in the URL of the main request (which is the only request
  19 // accessible from the UIWebView delegate).
  20
  21 namespace web {
  22
  23 // Generates a request-group ID.
  24 NSString* GenerateNewRequestGroupID();
  25
  26 // Extracts the requestGroupID embedded in a User-Agent string or nil if a
  27 // requestGroupID cannot be located.
  28 NSString* ExtractRequestGroupIDFromUserAgent(NSString* user_agent);
  29
  30 // Returns a new user agent, which is the result of the encoding of
  31 // |request_group_id| in |base_user_agent|. The request group ID can be later
  32 // extracted with ExtractRequestGroupIDFromUserAgent().
  33 NSString* AddRequestGroupIDToUserAgent(NSString* base_user_agent,
  34                                        NSString* request_group_id);
  35
  36 // Extracts the requestGroupID embedded in a NSURL or nil if a requestGroupID
  37 // cannot be located.
  38 NSString* ExtractRequestGroupIDFromURL(NSURL* url);
  39
  40 // Returns a new user agent, which is the result of the encoding of
  41 // |request_group_id| in |base_url|. The request group ID can be later extracted
  42 // with ExtractRequestGroupIDFromURL().
  43 NSURL* AddRequestGroupIDToURL(NSURL* base_url, NSString* request_group_id);
  44
  45 // Extracts the request group ID from |request| by retrieving it from the
  46 // user-agent if possible, and from the parent URL otherwise.
  47 // The ID can only be retrived from the parent URL if its scheme is
  48 // |application_scheme|.
  49 // The reason why the |application_scheme| case is different is because
  50 // UIWebView does not provide a "User-Agent" HTTP header for these requests.
  51 // The ID is then encoded in the URL of the main request, and thus sub-requests
  52 // have to look in their parent URL for the ID.
  53 NSString* ExtractRequestGroupIDFromRequest(NSURLRequest* request,
  54                                            NSString* application_scheme);
  55
  56 }  // namespace web
  57
  58 #endif  // IOS_WEB_NET_REQUEST_GROUP_UTIL_H_