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

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

Index: chrome/browser/media_galleries/fileapi/picasa/picasa_data_provider.cc
diff --git a/chrome/browser/media_galleries/fileapi/picasa/picasa_data_provider.cc b/chrome/browser/media_galleries/fileapi/picasa/picasa_data_provider.cc
index 1baa46038f476323443ebccc4847b22747b70889..b4a2df4b7479b11a0809abe8c2cc31fa3b9ed759 100644
--- a/chrome/browser/media_galleries/fileapi/picasa/picasa_data_provider.cc
+++ b/chrome/browser/media_galleries/fileapi/picasa/picasa_data_provider.cc
@@ -8,7 +8,10 @@
 
 #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"
@@ -22,6 +25,8 @@ namespace picasa {
 
 namespace {
 
+const char kPicasaTempDirName[] = "tmp";
+
 void RunAllCallbacks(
     std::queue<PicasaDataProvider::ReadyCallback>* ready_callbacks_queue,
     bool success) {
@@ -38,6 +43,30 @@ PicasaDataProvider::PicasaDataProvider(const base::FilePath& 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() {}
@@ -115,6 +144,19 @@ void PicasaDataProvider::InvalidateData() {
   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);
@@ -240,15 +282,4 @@ void PicasaDataProvider::UniquifyNames(const std::vector<AlbumInfo>& info_list,
   }
 }
 
-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