sync: Loop committing items without downloading updates

sync/engine/post_commit_message_command.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 "sync/engine/post_commit_message_command.h"
 
 #include <vector>
 
 #include "base/location.h"
 #include "sync/engine/syncer_proto_util.h"
-#include "sync/engine/syncproto.h"
 #include "sync/sessions/sync_session.h"
 
 using std::vector;
 
 namespace browser_sync {
 
-PostCommitMessageCommand::PostCommitMessageCommand() {}
+PostCommitMessageCommand::PostCommitMessageCommand(
+    const ClientToServerMessage& message,
+    ClientToServerResponse* response)
+  : commit_message_(message), commit_response_(response) {
+}
+
 PostCommitMessageCommand::~PostCommitMessageCommand() {}
 
 SyncerError PostCommitMessageCommand::ExecuteImpl(
     sessions::SyncSession* session) {
-  if (session->status_controller().commit_ids().empty())

[rlarocque, 2012/04/13 02:02:22]

This if statement is no longer necessary, we break out of the loop in syncer.cc
if this condition is true.

-    return SYNCER_OK;  // Nothing to commit.
-  ClientToServerResponse response;
-  syncable::Directory* dir = session->context()->directory();
-  sessions::StatusController* status = session->mutable_status_controller();
-  SyncerError result = SyncerProtoUtil::PostClientToServerMessage(
-      status->commit_message(), &response, session);
-  if (result != SYNCER_OK) {

[rlarocque, 2012/04/13 02:02:22]

I believe this is the wrong place to put this code.  There are other cases where
our changes don't get through that are detected in ProcessCommitResponse.  For
now I think it's safer to assert ProcessCommitResponse is always reponsible for
clearing the SYNCING bits no matter what, rather than having this command handle
some failures while letting ProcessCommitResponse handles the success and
remaining failure cases.

-    // None of our changes got through.  Clear the SYNCING bit which was
-    // set to true during BuildCommitCommand, and which may still be true.
-    // Not to be confused with IS_UNSYNCED, this bit is used to detect local
-    // changes to items that happen during the server Commit operation.
-    syncable::WriteTransaction trans(FROM_HERE, syncable::SYNCER, dir);
-    const vector<syncable::Id>& commit_ids = status->commit_ids();
-    for (size_t i = 0; i < commit_ids.size(); i++) {
-      syncable::MutableEntry entry(&trans, syncable::GET_BY_ID, commit_ids[i]);
-      entry.Put(syncable::SYNCING, false);
-    }
-    return result;
-  }
-
-  status->set_items_committed();
-  status->mutable_commit_response()->CopyFrom(response);
-  return SYNCER_OK;
+  return SyncerProtoUtil::PostClientToServerMessage(

[rlarocque, 2012/04/13 02:02:22]

Seeing how little is left of this class, I intend to remove it and inline this
function.  That will happen either in a future CL, or a later revision of this
CL.  I want to keep the diffs simple for now.  

+      commit_message_, commit_response_, session);
 }
 
 }  // namespace browser_sync