drive: Support offline delete

chrome/browser/chromeos/drive/sync_client.cc

 // Copyright (c) 2012 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/chromeos/drive/sync_client.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "chrome/browser/chromeos/drive/drive.pb.h"
 #include "chrome/browser/chromeos/drive/file_cache.h"
 #include "chrome/browser/chromeos/drive/file_system/download_operation.h"
 #include "chrome/browser/chromeos/drive/file_system/update_operation.h"
 #include "chrome/browser/chromeos/drive/file_system_util.h"
+#include "chrome/browser/chromeos/drive/sync/remove_performer.h"
 #include "chrome/browser/google_apis/task_util.h"
 #include "content/public/browser/browser_thread.h"
 
 using content::BrowserThread;
 
 namespace drive {
 namespace internal {
 
 namespace {
 
 // The delay constant is used to delay processing a sync task. We should not
 // process SyncTasks immediately for the following reasons:
 //
 // 1) For fetching, the user may accidentally click on "Make available
 //    offline" checkbox on a file, and immediately cancel it in a second.
 //    It's a waste to fetch the file in this case.
 //
 // 2) For uploading, file writing via HTML5 file system API is performed in
 //    two steps: 1) truncate a file to 0 bytes, 2) write contents. We
 //    shouldn't start uploading right after the step 1). Besides, the user
 //    may edit the same file repeatedly in a short period of time.
 //
 // TODO(satorux): We should find a way to handle the upload case more nicely,
 // and shorten the delay. crbug.com/134774
 const int kDelaySeconds = 5;
 
 // The delay constant is used to delay retrying a sync task on server errors.
 const int kLongDelaySeconds = 600;
 
-// Iterates cache entries and appends IDs to |to_fetch| if the file is pinned
-// but not fetched (not present locally), or to |to_upload| if the file is dirty
-// but not uploaded.
-void CollectBacklog(FileCache* cache,
+// Iterates entries and appends IDs to |to_fetch| if the file is pinned but not
+// fetched (not present locally), to |to_upload| if the file is dirty but not
+// uploaded, or to |to_remove| if the entry is locally deleted.
+void CollectBacklog(ResourceMetadata* metadata,
                     std::vector<std::string>* to_fetch,
-                    std::vector<std::string>* to_upload) {
+                    std::vector<std::string>* to_upload,
+                    std::vector<std::string>* to_remove) {
   DCHECK(to_fetch);
   DCHECK(to_upload);
+  DCHECK(to_remove);
 
-  scoped_ptr<FileCache::Iterator> it = cache->GetIterator();
+  scoped_ptr<ResourceMetadata::Iterator> it = metadata->GetIterator();
   for (; !it->IsAtEnd(); it->Advance()) {
-    const FileCacheEntry& cache_entry = it->GetValue();
     const std::string& local_id = it->GetID();
-    if (cache_entry.is_pinned() && !cache_entry.is_present())
-      to_fetch->push_back(local_id);
+    const ResourceEntry& entry = it->GetValue();
+    if (entry.parent_local_id() == util::kDriveOtherDirLocalId &&
+        entry.deleted())
+      to_remove->push_back(local_id);

[kinaba, 2013/11/12 06:21:29]

Probably we don't want to, say, fetch a pinned and removed file. It might be
better to continue to the next entry at this point.

[hashimoto, 2013/11/25 10:13:58]

Done.

 
-    if (cache_entry.is_dirty())
-      to_upload->push_back(local_id);
+    FileCacheEntry cache_entry;
+    if (it->GetCacheEntry(&cache_entry)) {
+      if (cache_entry.is_pinned() && !cache_entry.is_present())
+        to_fetch->push_back(local_id);
+
+      if (cache_entry.is_dirty())
+        to_upload->push_back(local_id);
+    }
   }
   DCHECK(!it->HasError());
 }
 
 // Iterates cache entries and collects IDs of ones with obsolete cache files.
 void CheckExistingPinnedFiles(ResourceMetadata* metadata,
                               FileCache* cache,
                               std::vector<std::string>* local_ids) {
   scoped_ptr<FileCache::Iterator> it = cache->GetIterator();
   for (; !it->IsAtEnd(); it->Advance()) {
@@ skipping 49 matching lines @@
           observer,
           scheduler,
           metadata,
           cache,
           temporary_file_directory)),
       update_operation_(new file_system::UpdateOperation(blocking_task_runner,
                                                          observer,
                                                          scheduler,
                                                          metadata,
                                                          cache)),
+      remove_performer_(new RemovePerformer(blocking_task_runner,
+                                            scheduler,
+                                            metadata)),
       delay_(base::TimeDelta::FromSeconds(kDelaySeconds)),
       long_delay_(base::TimeDelta::FromSeconds(kLongDelaySeconds)),
       weak_ptr_factory_(this) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
 
 SyncClient::~SyncClient() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
 
 void SyncClient::StartProcessingBacklog() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   std::vector<std::string>* to_fetch = new std::vector<std::string>;
   std::vector<std::string>* to_upload = new std::vector<std::string>;
+  std::vector<std::string>* to_remove = new std::vector<std::string>;
   blocking_task_runner_->PostTaskAndReply(
       FROM_HERE,
-      base::Bind(&CollectBacklog, cache_, to_fetch, to_upload),
+      base::Bind(&CollectBacklog, metadata_, to_fetch, to_upload, to_remove),
       base::Bind(&SyncClient::OnGetLocalIdsOfBacklog,
                  weak_ptr_factory_.GetWeakPtr(),
                  base::Owned(to_fetch),
-                 base::Owned(to_upload)));
+                 base::Owned(to_upload),
+                 base::Owned(to_remove)));
 }
 
 void SyncClient::StartCheckingExistingPinnedFiles() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   std::vector<std::string>* local_ids = new std::vector<std::string>;
   blocking_task_runner_->PostTaskAndReply(
       FROM_HERE,
       base::Bind(&CheckExistingPinnedFiles,
                  metadata_,
@@ skipping 16 matching lines @@
   // TODO(kinaba): Cancel tasks in JobScheduler as well. crbug.com/248856
   pending_fetch_list_.erase(local_id);
 }
 
 void SyncClient::AddUploadTask(const std::string& local_id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   AddTaskToQueue(UPLOAD, local_id, delay_);
 }
 
+void SyncClient::AddRemoveTask(const std::string& local_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  DVLOG(1) << "Removing " << local_id;
+  remove_performer_->Remove(local_id,
+                            base::Bind(&SyncClient::OnRemoveComplete,
+                                       weak_ptr_factory_.GetWeakPtr(),
+                                       local_id));
+}
+
 void SyncClient::AddTaskToQueue(SyncType type,
                                 const std::string& local_id,
                                 const base::TimeDelta& delay) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   // If the same task is already queued, ignore this task.
   switch (type) {
     case FETCH:
       if (fetch_list_.find(local_id) == fetch_list_.end()) {
         fetch_list_.insert(local_id);
@@ skipping 52 matching lines @@
                          : file_system::UpdateOperation::NO_CONTENT_CHECK,
           base::Bind(&SyncClient::OnUploadFileComplete,
                      weak_ptr_factory_.GetWeakPtr(),
                      local_id));
       break;
   }
 }
 
 void SyncClient::OnGetLocalIdsOfBacklog(
     const std::vector<std::string>* to_fetch,
-    const std::vector<std::string>* to_upload) {
+    const std::vector<std::string>* to_upload,
+    const std::vector<std::string>* to_remove) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   // Give priority to upload tasks over fetch tasks, so that dirty files are
   // uploaded as soon as possible.
   for (size_t i = 0; i < to_upload->size(); ++i) {
     const std::string& local_id = (*to_upload)[i];
     DVLOG(1) << "Queuing to upload: " << local_id;
     AddTaskToQueue(UPLOAD_NO_CONTENT_CHECK, local_id, delay_);
   }
 
   for (size_t i = 0; i < to_fetch->size(); ++i) {
     const std::string& local_id = (*to_fetch)[i];
     DVLOG(1) << "Queuing to fetch: " << local_id;
     AddTaskToQueue(FETCH, local_id, delay_);
   }
+
+  for (size_t i = 0; i < to_remove->size(); ++i) {
+    const std::string& local_id = (*to_remove)[i];
+    DVLOG(1) << "Queuing to remove: " << local_id;
+    AddRemoveTask(local_id);
+  }
 }
 
 void SyncClient::AddFetchTasks(const std::vector<std::string>* local_ids) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   for (size_t i = 0; i < local_ids->size(); ++i)
     AddFetchTask((*local_ids)[i]);
 }
 
 void SyncClient::OnFetchFileComplete(const std::string& local_id,
@@ skipping 47 matching lines @@
         // Re-queue the task so that we'll retry once the service is back.
         AddTaskToQueue(UPLOAD_NO_CONTENT_CHECK, local_id, long_delay_);
         break;
       default:
         LOG(WARNING) << "Failed to upload " << local_id << ": "
                      << FileErrorToString(error);
     }
   }
 }
 
+void SyncClient::OnRemoveComplete(const std::string& local_id,
+                                  FileError error) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  if (error == FILE_ERROR_OK) {
+    DVLOG(1) << "Removed " << local_id;
+  } else {
+    switch (error) {
+      case FILE_ERROR_NO_CONNECTION:
+        // Re-queue the task so that we'll retry once the connection is back.
+        AddRemoveTask(local_id);
+        break;
+      case FILE_ERROR_SERVICE_UNAVAILABLE:
+        // Re-queue the task so that we'll retry once the service is back.
+        AddRemoveTask(local_id);

[kinaba, 2013/11/12 06:21:29]

AddTaskToQueue posts the task after a long_delay_, while AddRemoveTask retries
immediately. Is it fine?

[hashimoto, 2013/11/25 10:13:58]

Done.

+        break;
+      default:
+        LOG(WARNING) << "Failed to remove " << local_id << ": "
+                     << FileErrorToString(error);
+    }
+  }
+}
+
 }  // namespace internal
 }  // namespace drive