chrome/browser/prerender/prerender_resource_throttle.h

   1 // Copyright 2013 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 CHROME_BROWSER_PRERENDER_PRERENDER_RESOURCE_THROTTLE_H_
   6 #define CHROME_BROWSER_PRERENDER_PRERENDER_RESOURCE_THROTTLE_H_
   7
   8 #include <string>
   9
  10 #include "base/macros.h"
  11 #include "base/memory/weak_ptr.h"
  12 #include "content/public/browser/resource_throttle.h"
  13 #include "content/public/common/resource_type.h"
  14
  15 class GURL;
  16
  17 namespace net {
  18 class URLRequest;
  19 }
  20
  21 namespace prerender {
  22 class PrerenderContents;
  23
  24 // This class implements policy on resource requests in prerenders.  It cancels
  25 // prerenders on certain requests.  It also defers certain requests until after
  26 // the prerender is swapped in.
  27 //
  28 // TODO(davidben): Experiment with deferring network requests that
  29 // would otherwise cancel the prerender.
  30 class PrerenderResourceThrottle
  31     : public content::ResourceThrottle,
  32       public base::SupportsWeakPtr<PrerenderResourceThrottle> {
  33  public:
  34   explicit PrerenderResourceThrottle(net::URLRequest* request);
  35
  36   // content::ResourceThrottle implementation:
  37   void WillStartRequest(bool* defer) override;
  38   void WillRedirectRequest(const net::RedirectInfo& redirect_info,
  39                            bool* defer) override;
  40   const char* GetNameForLogging() const override;
  41
  42   // Called by the PrerenderContents when a prerender becomes visible.
  43   // May only be called if currently throttling the resource.
  44   void Resume();
  45
  46   static void OverridePrerenderContentsForTesting(PrerenderContents* contents);
  47
  48  private:
  49   // Helper method to cancel the request. May only be called if currently
  50   // throttling the resource.
  51   void Cancel();
  52
  53   static void WillStartRequestOnUI(
  54       const base::WeakPtr<PrerenderResourceThrottle>& throttle,
  55       const std::string& method,
  56       content::ResourceType resource_type,
  57       int render_process_id,
  58       int render_frame_id,
  59       const GURL& url);
  60
  61   static void WillRedirectRequestOnUI(
  62       const base::WeakPtr<PrerenderResourceThrottle>& throttle,
  63       const std::string& follow_only_when_prerender_shown_header,
  64       content::ResourceType resource_type,
  65       bool async,
  66       int render_process_id,
  67       int render_frame_id,
  68       const GURL& new_url);
  69
  70   // Helper to return the PrerenderContents given a render frame id. May return
  71   // NULL if it's gone.
  72   static PrerenderContents* PrerenderContentsFromRenderFrame(
  73       int render_process_id, int render_frame_id);
  74
  75   net::URLRequest* request_;
  76
  77   DISALLOW_COPY_AND_ASSIGN(PrerenderResourceThrottle);
  78 };
  79
  80 }  // namespace prerender
  81
  82 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_RESOURCE_THROTTLE_H_