Media Galleries API Picasa: Add file watch to invalidate database data on disk write.

chrome/browser/media_galleries/fileapi/picasa/picasa_data_provider.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/media_galleries/fileapi/picasa/picasa_data_provider.h"
 
 #include <utility>
 
 #include "base/basictypes.h"
 #include "base/bind_helpers.h"
+#include "base/callback.h"
+#include "base/file_util.h"
 #include "base/strings/stringprintf.h"
+#include "chrome/browser/media_galleries/fileapi/data_provider_helper.h"
 #include "chrome/browser/media_galleries/fileapi/media_file_system_backend.h"
 #include "chrome/browser/media_galleries/fileapi/safe_picasa_album_table_reader.h"
 #include "chrome/browser/media_galleries/fileapi/safe_picasa_albums_indexer.h"
 #include "chrome/browser/media_galleries/imported_media_gallery_registry.h"
 #include "webkit/browser/fileapi/file_system_operation_context.h"
 #include "webkit/browser/fileapi/file_system_url.h"
 
 using chrome::MediaFileSystemBackend;
 
 namespace picasa {
 
 namespace {
 
+const char kPicasaTempDirName[] = "tmp";
+
 void RunAllCallbacks(
     std::queue<PicasaDataProvider::ReadyCallback>* ready_callbacks_queue,
     bool success) {
   while (!ready_callbacks_queue->empty()) {
     ready_callbacks_queue->front().Run(success);
     ready_callbacks_queue->pop();
   }
 }
 
 }  // namespace
 
 PicasaDataProvider::PicasaDataProvider(const base::FilePath& database_path)
     : database_path_(database_path),
       state_(STALE_DATA_STATE),
       weak_factory_(this) {
   DCHECK(MediaFileSystemBackend::CurrentlyOnMediaTaskRunnerThread());
+
+  chrome::StartFilePathWatchOnMediaTaskRunner(
+      database_path_.DirName().AppendASCII(kPicasaTempDirName),
+      true /* recursive */,
+      base::Bind(&PicasaDataProvider::OnTempDirWatchStarted,
+                 weak_factory_.GetWeakPtr()),
+      base::Bind(&PicasaDataProvider::OnTempDirChanged,
+                 weak_factory_.GetWeakPtr()));
+}
+
+PicasaDataProvider::PicasaDataProvider(const base::FilePath& database_path,
+                                       const base::FilePath& temp_dir_path)
+    : database_path_(database_path),
+      state_(STALE_DATA_STATE),
+      weak_factory_(this) {
+  DCHECK(MediaFileSystemBackend::CurrentlyOnMediaTaskRunnerThread());
+
+  chrome::StartFilePathWatchOnMediaTaskRunner(
+      temp_dir_path,
+      true /* recursive */,
+      base::Bind(&PicasaDataProvider::OnTempDirWatchStarted,
+                 weak_factory_.GetWeakPtr()),
+      base::Bind(&PicasaDataProvider::OnTempDirChanged,
+                 weak_factory_.GetWeakPtr()));
 }
 
 PicasaDataProvider::~PicasaDataProvider() {}
 
 void PicasaDataProvider::RefreshData(DataType needed_data,
                                      const ReadyCallback& ready_callback) {
   DCHECK(MediaFileSystemBackend::CurrentlyOnMediaTaskRunnerThread());
   // TODO(tommycli): Need to watch the database_path_ folder and handle
   // rereading the data when it changes.
 
@@ skipping 57 matching lines @@
   // Set data state to stale and ignore responses from any in-flight processes.
   // TODO(tommycli): Implement and call Cancel function for these
   // UtilityProcessHostClients to actually kill the in-flight processes.
   state_ = STALE_DATA_STATE;
   album_table_reader_ = NULL;
   albums_indexer_ = NULL;
 
   DoRefreshIfNecessary();
 }
 
+void PicasaDataProvider::OnTempDirWatchStarted(
+    scoped_ptr<base::FilePathWatcher> temp_dir_watcher) {
+  DCHECK(MediaFileSystemBackend::CurrentlyOnMediaTaskRunnerThread());
+  temp_dir_watcher_.reset(temp_dir_watcher.release());
+}
+
+void PicasaDataProvider::OnTempDirChanged(const base::FilePath& temp_dir_path,
+                                          bool error) {
+  DCHECK(MediaFileSystemBackend::CurrentlyOnMediaTaskRunnerThread());
+  if (file_util::IsDirectoryEmpty(temp_dir_path))
+    InvalidateData();
+}
+
 void PicasaDataProvider::DoRefreshIfNecessary() {
   DCHECK(state_ != INVALID_DATA_STATE);
   DCHECK(state_ != ALBUMS_IMAGES_FRESH_STATE);
   DCHECK(!(album_table_reader_ && albums_indexer_));
 
   if (album_list_ready_callbacks_.empty() &&
       albums_index_ready_callbacks_.empty()) {
     return;
   }
 
@@ skipping 105 matching lines @@
 
     if (total_counts[name] != 1) {
       name = base::StringPrintf("%s (%d)", name.c_str(),
                                 ++current_counts[name]);
     }
 
     result_map->insert(std::pair<std::string, AlbumInfo>(name, info_list[i]));
   }
 }
 
-void PicasaDataProvider::SetDatabasePathForTesting(
-    const base::FilePath& database_path) {
-  database_path_ = database_path;
-}
-
-void PicasaDataProvider::SetAlbumMapsForTesting(const AlbumMap& album_map,
-                                                const AlbumMap& folder_map) {
-  album_map_ = album_map;
-  folder_map_ = folder_map;
-}
-
 }  // namespace picasa