[GCM] Add basic collapse key support for upstream

google_apis/gcm/engine/gcm_store_impl.cc

 // Copyright 2014 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 "google_apis/gcm/engine/gcm_store_impl.h"
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/file_util.h"
@@ skipping 692 matching lines @@
                    message,
                    base::Bind(&GCMStoreImpl::AddOutgoingMessageContinuation,
                               weak_ptr_factory_.GetWeakPtr(),
                               callback,
                               app_id)));
     return true;
   }
   return false;
 }
 
+void GCMStoreImpl::OverwriteOutgoingMessage(const std::string& persistent_id,
+                                            const MCSMessage& message,
+                                            const UpdateCallback& callback) {
+  DCHECK_EQ(message.tag(), kDataMessageStanzaTag);
+  std::string app_id = reinterpret_cast<const mcs_proto::DataMessageStanza*>(
+      &message.GetProtobuf())->from();

[fgorski, 2014/01/27 17:39:38]

app_id is stored in category

[Nicolas Zea, 2014/01/28 08:15:35]

from is supposed to store project id, and category stores package name, right?
Id seems a better key to use (and is also what the gcm_store_impl is using for
per-app message limits)

[fgorski, 2014/01/28 18:10:27]

Ok. For upstream messages the following holds true:
* to stores project Id, and that is what you want to use,
* from is set to an arbitrary string ("gcm@chrome.com"),
* category indeed stores app_id/package name.

From would be set to sender ID/project Id on downstream messages.

[Nicolas Zea, 2014/01/31 11:58:43]

Done.

+  DCHECK(!app_id.empty());
+  // There should already be pending messages for this app.
+  DCHECK(app_message_counts_.count(app_id));
+  // TODO(zea); consider verifying the specific message already exists.
+  blocking_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&GCMStoreImpl::Backend::AddOutgoingMessage,
+                 backend_,
+                 persistent_id,
+                 message,
+                 callback));
+}
+
 void GCMStoreImpl::RemoveOutgoingMessage(const std::string& persistent_id,
                                          const UpdateCallback& callback) {
   blocking_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&GCMStoreImpl::Backend::RemoveOutgoingMessages,
                  backend_,
                  PersistentIdList(1, persistent_id),
                  base::Bind(&GCMStoreImpl::RemoveOutgoingMessagesContinuation,
                             weak_ptr_factory_.GetWeakPtr(),
                             callback)));
@@ skipping 91 matching lines @@
            removed_message_counts.begin();
        iter != removed_message_counts.end(); ++iter) {
     DCHECK_NE(app_message_counts_.count(iter->first), 0U);
     app_message_counts_[iter->first] -= iter->second;
     DCHECK_GE(app_message_counts_[iter->first], 0);
   }
   callback.Run(true);
 }
 
 }  // namespace gcm