Implement Invalidator::Acknowledge

sync/notifier/sync_invalidation_listener.cc

Index: sync/notifier/sync_invalidation_listener.cc
diff --git a/sync/notifier/sync_invalidation_listener.cc b/sync/notifier/sync_invalidation_listener.cc
index 4e57bb85ed5a2096072ab572573d4d7cf01e431b..28b37bc07873bf829ad9342ac1cefc2ba75006b4 100644
--- a/sync/notifier/sync_invalidation_listener.cc
+++ b/sync/notifier/sync_invalidation_listener.cc
@@ -4,9 +4,9 @@
 
 #include "sync/notifier/sync_invalidation_listener.h"
 
-#include <string>
 #include <vector>
 
+#include "base/bind.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
@@ -29,8 +29,11 @@ namespace syncer {
 SyncInvalidationListener::Delegate::~Delegate() {}
 
 SyncInvalidationListener::SyncInvalidationListener(
+    base::TickClock* tick_clock,
     scoped_ptr<notifier::PushClient> push_client)
-    : push_client_(push_client.get()),
+    : weak_ptr_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)),
+      ack_tracker_(tick_clock, ALLOW_THIS_IN_INITIALIZER_LIST(this)),
+      push_client_(push_client.get()),
       sync_system_resources_(push_client.Pass(),
                              ALLOW_THIS_IN_INITIALIZER_LIST(this)),
       delegate_(NULL),
@@ -105,6 +108,19 @@ void SyncInvalidationListener::Start(
       FROM_HERE,
       &InvalidationStateTracker::SetInvalidatorClientId,
       client_id);
+
+  // Set up reminders for any invalidations that have not been locally
+  // acknowledged.
+  ObjectIdSet unacknowledged_ids;
+  for (InvalidationStateMap::const_iterator it =
+           invalidation_state_map_.begin();
+       it != invalidation_state_map_.end(); ++it) {
+    if (it->second.expected.Equals(it->second.current))
+      continue;
+    unacknowledged_ids.insert(it->first);
+  }
+  if (!unacknowledged_ids.empty())
+    ack_tracker_.Track(unacknowledged_ids);
 }
 
 void SyncInvalidationListener::UpdateCredentials(
@@ -124,6 +140,27 @@ void SyncInvalidationListener::UpdateRegisteredIds(const ObjectIdSet& ids) {
   }
 }
 
+void SyncInvalidationListener::Acknowledge(const invalidation::ObjectId& id,
+                                           const AckHandle& ack_handle) {
+  DCHECK(CalledOnValidThread());
+  InvalidationStateMap::iterator state_it = invalidation_state_map_.find(id);
+  if (state_it == invalidation_state_map_.end())
+    return;
+  invalidation_state_tracker_.Call(
+      FROM_HERE,
+      &InvalidationStateTracker::Acknowledge,
+      id,
+      ack_handle);
+  state_it->second.current = ack_handle;
+  if (state_it->second.expected.Equals(ack_handle)) {
+    // If the received ack matches the expected ack, then we no longer need to
+    // keep track of |id| since it is up-to-date.
+    ObjectIdSet ids;
+    ids.insert(id);
+    ack_tracker_.Ack(ids);
+  }
+}
+
 void SyncInvalidationListener::Ready(
     invalidation::InvalidationClient* client) {
   DCHECK(CalledOnValidThread());
@@ -167,17 +204,15 @@ void SyncInvalidationListener::Invalidate(
   DVLOG(2) << "Setting max invalidation version for " << ObjectIdToString(id)
            << " to " << invalidation.version();
   invalidation_state_map_[id].version = invalidation.version();
+  invalidation_state_map_[id].payload = payload;
   invalidation_state_tracker_.Call(
       FROM_HERE,
       &InvalidationStateTracker::SetMaxVersionAndPayload,
       id, invalidation.version(), payload);
 
-  ObjectIdInvalidationMap invalidation_map;
-  invalidation_map[id].payload = payload;
-  EmitInvalidation(invalidation_map);
-  // TODO(akalin): We should really acknowledge only after we get the
-  // updates from the sync server. (see http://crbug.com/78462).
-  client->Acknowledge(ack_handle);
+  ObjectIdSet ids;
+  ids.insert(id);
+  PrepareInvalidation(ids, payload, client, ack_handle);
 }
 
 void SyncInvalidationListener::InvalidateUnknownVersion(
@@ -188,12 +223,9 @@ void SyncInvalidationListener::InvalidateUnknownVersion(
   DCHECK_EQ(client, invalidation_client_.get());
   DVLOG(1) << "InvalidateUnknownVersion";
 
-  ObjectIdInvalidationMap invalidation_map;
-  invalidation_map[object_id].payload = std::string();
-  EmitInvalidation(invalidation_map);
-  // TODO(akalin): We should really acknowledge only after we get the
-  // updates from the sync server. (see http://crbug.com/78462).
-  client->Acknowledge(ack_handle);
+  ObjectIdSet ids;
+  ids.insert(object_id);
+  PrepareInvalidation(ids, std::string(), client, ack_handle);
 }
 
 // This should behave as if we got an invalidation with version
@@ -205,17 +237,60 @@ void SyncInvalidationListener::InvalidateAll(
   DCHECK_EQ(client, invalidation_client_.get());
   DVLOG(1) << "InvalidateAll";
 
-  const ObjectIdInvalidationMap& invalidation_map =
-      ObjectIdSetToInvalidationMap(registered_ids_, std::string());
-  EmitInvalidation(invalidation_map);
-  // TODO(akalin): We should really acknowledge only after we get the
-  // updates from the sync server. (see http://crbug.com/76482).
-  client->Acknowledge(ack_handle);
+  PrepareInvalidation(registered_ids_, std::string(), client, ack_handle);
+}
+
+void SyncInvalidationListener::PrepareInvalidation(
+    const ObjectIdSet& ids,
+    const std::string& payload,
+    invalidation::InvalidationClient* client,
+    const invalidation::AckHandle& ack_handle) {
+  DCHECK(CalledOnValidThread());
+
+  // A server invalidation resets the local retry count.
+  ack_tracker_.Ack(ids);
+  invalidation_state_tracker_.Call(
+      FROM_HERE,
+      &InvalidationStateTracker::GenerateAckHandles,
+      ids,
+      base::MessageLoopProxy::current(),
+      base::Bind(&SyncInvalidationListener::EmitInvalidation,
+                 weak_ptr_factory_.GetWeakPtr(),
+                 ids,
+                 payload,
+                 client,
+                 ack_handle));
 }
 
 void SyncInvalidationListener::EmitInvalidation(
-    const ObjectIdInvalidationMap& invalidation_map) {
+    const ObjectIdSet& ids,
+    const std::string& payload,
+    invalidation::InvalidationClient* client,
+    const invalidation::AckHandle& ack_handle,
+    const AckHandleMap& local_ack_handles) {
   DCHECK(CalledOnValidThread());
+  ObjectIdInvalidationMap invalidation_map =
+      ObjectIdSetToInvalidationMap(ids, payload);
+  for (AckHandleMap::const_iterator it = local_ack_handles.begin();
+       it != local_ack_handles.end(); ++it) {
+    // Update in-memory copy of the invalidation state.
+    invalidation_state_map_[it->first].expected = it->second;
+    invalidation_map[it->first].ack_handle = it->second;
+  }
+  ack_tracker_.Track(ids);
+  delegate_->OnInvalidate(invalidation_map);
+  client->Acknowledge(ack_handle);
+}
+
+void SyncInvalidationListener::OnTimeout(const ObjectIdSet& ids) {
+  ObjectIdInvalidationMap invalidation_map;
+  for (ObjectIdSet::const_iterator it = ids.begin(); it != ids.end(); ++it) {
+    Invalidation invalidation;
+    invalidation.ack_handle = invalidation_state_map_[*it].expected;
+    invalidation.payload = invalidation_state_map_[*it].payload;
+    invalidation_map.insert(std::make_pair(*it, invalidation));
+  }
+
   delegate_->OnInvalidate(invalidation_map);
 }
 
@@ -306,6 +381,7 @@ void SyncInvalidationListener::DoRegistrationUpdate() {
   }
   invalidation_state_tracker_.Call(
       FROM_HERE, &InvalidationStateTracker::Forget, unregistered_ids);
+  ack_tracker_.Ack(unregistered_ids);
 }
 
 void SyncInvalidationListener::StopForTest() {
@@ -318,12 +394,18 @@ InvalidationStateMap SyncInvalidationListener::GetStateMapForTest() const {
   return invalidation_state_map_;
 }
 
+AckTracker* SyncInvalidationListener::GetAckTrackerForTest() {
+  return &ack_tracker_;
+}
+
 void SyncInvalidationListener::Stop() {
   DCHECK(CalledOnValidThread());
   if (!invalidation_client_.get()) {
     return;
   }
 
+  ack_tracker_.Clear();
+
   registration_manager_.reset();
   sync_system_resources_.Stop();
   invalidation_client_->Stop();