components/enhanced_bookmarks/bookmark_image_service.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 #ifndef COMPONENTS_ENHANCED_BOOKMARKS_BOOKMARK_IMAGE_SERVICE_H_
   5 #define COMPONENTS_ENHANCED_BOOKMARKS_BOOKMARK_IMAGE_SERVICE_H_
   6
   7 #include "base/files/file_path.h"
   8 #include "base/memory/scoped_ptr.h"
   9 #include "base/memory/singleton.h"
  10 #include "components/bookmarks/browser/bookmark_model_observer.h"
  11 #include "components/enhanced_bookmarks/image_record.h"
  12 #include "components/enhanced_bookmarks/image_store.h"
  13 #include "components/keyed_service/core/keyed_service.h"
  14 #include "net/url_request/url_request.h"
  15 #include "url/gurl.h"
  16
  17 namespace base {
  18 class SingleThreadTaskRunner;
  19 }
  20
  21 namespace bookmarks {
  22 class BookmarkNode;
  23 }
  24
  25 namespace enhanced_bookmarks {
  26
  27 class EnhancedBookmarkModel;
  28
  29 // The BookmarkImageService stores salient images for bookmarks.
  30 class BookmarkImageService : public KeyedService,
  31                              public bookmarks::BookmarkModelObserver,
  32                              public base::NonThreadSafe {
  33  public:
  34   BookmarkImageService(const base::FilePath& path,
  35                        EnhancedBookmarkModel* enhanced_bookmark_model,
  36                        scoped_refptr<base::SequencedWorkerPool> pool);
  37   BookmarkImageService(scoped_ptr<ImageStore> store,
  38                        EnhancedBookmarkModel* enhanced_bookmark_model,
  39                        scoped_refptr<base::SequencedWorkerPool> pool);
  40
  41   ~BookmarkImageService() override;
  42
  43   typedef base::Callback<void(const ImageRecord&)> ImageCallback;
  44
  45   // KeyedService:
  46   void Shutdown() override;
  47
  48   // Returns a salient image for a URL. This may trigger a network request for
  49   // the image if the image was not retrieved before and if a bookmark node has
  50   // a URL for this salient image available.  The image (which may be empty) is
  51   // sent via the callback. The callback may be called synchronously if it is
  52   // possible. The callback is always triggered on the main thread.
  53   void SalientImageForUrl(const GURL& page_url, ImageCallback callback);
  54
  55   // bookmarks::BookmarkModelObserver:
  56   void BookmarkNodeRemoved(bookmarks::BookmarkModel* model,
  57                            const bookmarks::BookmarkNode* parent,
  58                            int old_index,
  59                            const bookmarks::BookmarkNode* node,
  60                            const std::set<GURL>& removed_urls) override;
  61   void BookmarkModelLoaded(bookmarks::BookmarkModel* model,
  62                            bool ids_reassigned) override;
  63   void BookmarkNodeMoved(bookmarks::BookmarkModel* model,
  64                          const bookmarks::BookmarkNode* old_parent,
  65                          int old_index,
  66                          const bookmarks::BookmarkNode* new_parent,
  67                          int new_index) override;
  68   void BookmarkNodeAdded(bookmarks::BookmarkModel* model,
  69                          const bookmarks::BookmarkNode* parent,
  70                          int index) override;
  71   void OnWillChangeBookmarkNode(bookmarks::BookmarkModel* model,
  72                                 const bookmarks::BookmarkNode* node) override;
  73   void BookmarkNodeChanged(bookmarks::BookmarkModel* model,
  74                            const bookmarks::BookmarkNode* node) override;
  75   void BookmarkNodeFaviconChanged(bookmarks::BookmarkModel* model,
  76                                   const bookmarks::BookmarkNode* node) override;
  77   void BookmarkNodeChildrenReordered(
  78       bookmarks::BookmarkModel* model,
  79       const bookmarks::BookmarkNode* node) override;
  80   void BookmarkAllUserNodesRemoved(bookmarks::BookmarkModel* model,
  81                                    const std::set<GURL>& removed_urls) override;
  82
  83  protected:
  84   // Returns true if the image for the page_url is currently being fetched.
  85   bool IsPageUrlInProgress(const GURL& page_url);
  86
  87   // Stores the new image to local storage. If update_bookmarks is true, relates
  88   // the corresponding bookmark to image_url.
  89   void ProcessNewImage(const GURL& page_url,
  90                        bool update_bookmarks,
  91                        const GURL& image_url,
  92                        const gfx::Image& image);
  93
  94   // Resizes large images to proper size that fits device display. This method
  95   // should _not_ run on the UI thread.
  96   virtual gfx::Image ResizeImage(gfx::Image image) = 0;
  97
  98   // Sets a new image for a bookmark. If the given page_url is bookmarked and
  99   // the image is retrieved from the image_url, then the image is locally
 100   // stored. If update_bookmark is true the URL is also added to the bookmark.
 101   virtual void RetrieveSalientImage(
 102       const GURL& page_url,
 103       const GURL& image_url,
 104       const std::string& referrer,
 105       net::URLRequest::ReferrerPolicy referrer_policy,
 106       bool update_bookmark) = 0;
 107
 108   // Retrieves a salient image for a given page_url by downloading the image in
 109   // one of the bookmark.
 110   virtual void RetrieveSalientImageForPageUrl(const GURL& page_url);
 111
 112   // PageUrls currently in the progress of being retrieved.
 113   std::set<GURL> in_progress_page_urls_;
 114
 115   // Cached pointer to the bookmark model.
 116   EnhancedBookmarkModel* enhanced_bookmark_model_;
 117
 118  private:
 119   // If fetch_from_web is true, retrieves the salient image via a network
 120   // request; else only gets the image from local storage.
 121   void SalientImageForUrl(const GURL& page_url,
 122                           bool fetch_from_web,
 123                           ImageCallback stack_callback);
 124
 125   // Processes the requests that have been waiting on an image.
 126   void ProcessRequests(const GURL& page_url, const ImageRecord& image);
 127
 128   // Once an image is retrieved this method calls ResizeImage() and updates the
 129   // store with the smaller image, then returns the newly formed ImageRecord.
 130   // This is typically called on |pool_|, the background sequenced worker pool
 131   // for this object.
 132   ImageRecord ResizeAndStoreImage(const gfx::Image& image,
 133                                   const GURL& image_url,
 134                                   const GURL& page_url);
 135
 136   // Calls |StoreImage| in the background.  This should only be called from the
 137   // main thread.
 138   void PostTaskToStoreImage(const gfx::Image& image,
 139                             const GURL& image_url,
 140                             const GURL& page_url);
 141
 142   // Called when |StoreImage| as been posted.  This should only be called from
 143   // the main thread.
 144   void OnStoreImagePosted(const GURL& page_url, const ImageRecord& image);
 145
 146   // Called when retrieving an image from the image store fails, to trigger
 147   // retrieving the image from the url stored in the bookmark (if any).
 148   void FetchCallback(const GURL& page_url,
 149                      ImageCallback original_callback,
 150                      const ImageRecord& record);
 151
 152   // Remove the image stored for this bookmark (if it exists). Called when a
 153   // bookmark is deleted.
 154   void RemoveImageForUrl(const GURL& url);
 155
 156   // Moves an image from one url to another.
 157   void ChangeImageURL(const GURL& from, const GURL& to);
 158
 159   // Removes all the entries in the image service.
 160   void ClearAll();
 161
 162   // The image store can only be accessed from the blocking pool.
 163   // RetrieveImageFromStore starts a request to retrieve the image and returns
 164   // the result via a callback. RetrieveImageFromStore must be called on the
 165   // main thread and the callback will be called on the main thread as well. The
 166   // callback will always be called. The returned image is nil if the image is
 167   // not present in the store.
 168   void RetrieveImageFromStore(const GURL& page_url, ImageCallback callback);
 169
 170   // Maps a pageUrl to an image.
 171   scoped_ptr<ImageStore> store_;
 172
 173   // All the callbacks waiting for a particular image.
 174   std::map<const GURL, std::vector<ImageCallback>> callbacks_;
 175
 176   // When a bookmark is changed, two messages are received on the
 177   // bookmarkModelObserver, one with the old state, one with the new. The url
 178   // before the change is saved in this instance variable.
 179   GURL previous_url_;
 180
 181   // The worker pool to enqueue the requests onto.
 182   scoped_refptr<base::SequencedWorkerPool> pool_;
 183   DISALLOW_COPY_AND_ASSIGN(BookmarkImageService);
 184 };
 185
 186 }  // namespace enhanced_bookmarks
 187
 188 #endif  // COMPONENTS_ENHANCED_BOOKMARKS_BOOKMARK_IMAGE_SERVICE_H_
 189