[BackgroundSync] Initial land of the BackgroundSyncManager

content/browser/background_sync/background_sync_manager.cc

+// Copyright 2015 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 "content/browser/background_sync/background_sync_manager.h"
+
+#include "base/barrier_closure.h"
+#include "base/bind.h"
+#include "content/browser/background_sync/background_sync.pb.h"
+#include "content/browser/service_worker/service_worker_context_wrapper.h"
+#include "content/browser/service_worker/service_worker_storage.h"
+#include "content/public/browser/browser_thread.h"
+
+namespace {
+const char kBackgroundSyncUserDataKey[] = "BackgroundSyncUserData";
+}
+
+namespace content {
+
+const BackgroundSyncManager::BackgroundSyncRegistration::RegistrationId
+    BackgroundSyncManager::BackgroundSyncRegistration::kInvalidRegistrationId =
+        -1;
+
+const BackgroundSyncManager::BackgroundSyncRegistration::RegistrationId
+    BackgroundSyncManager::BackgroundSyncRegistrations::kInitialId = 0;
+
+BackgroundSyncManager::BackgroundSyncRegistrations::
+    BackgroundSyncRegistrations()
+    : next_id(kInitialId) {
+}
+BackgroundSyncManager::BackgroundSyncRegistrations::BackgroundSyncRegistrations(
+    BackgroundSyncRegistration::RegistrationId next_id)
+    : next_id(next_id) {
+}
+BackgroundSyncManager::BackgroundSyncRegistrations::
+    ~BackgroundSyncRegistrations() {
+}
+
+// static
+scoped_ptr<BackgroundSyncManager> BackgroundSyncManager::Create(
+    const scoped_refptr<ServiceWorkerContextWrapper>& service_worker_context) {
+  BackgroundSyncManager* sync_manager =
+      new BackgroundSyncManager(service_worker_context);
+  sync_manager->Init();
+  return make_scoped_ptr(sync_manager);
+}
+
+BackgroundSyncManager::~BackgroundSyncManager() {
+}
+
+void BackgroundSyncManager::Register(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& sync_registration,
+    const StatusAndRegistrationCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK_EQ(BackgroundSyncRegistration::kInvalidRegistrationId,
+            sync_registration.id);
+
+  StatusAndRegistrationCallback pending_callback =
+      base::Bind(&BackgroundSyncManager::PendingStatusAndRegistrationCallback,
+                 weak_ptr_factory_.GetWeakPtr(), callback);
+
+  op_scheduler_.ScheduleOperation(base::Bind(
+      &BackgroundSyncManager::RegisterImpl, weak_ptr_factory_.GetWeakPtr(),
+      origin, sw_registration_id, sync_registration, pending_callback));
+}
+
+void BackgroundSyncManager::Unregister(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const std::string& sync_registration_name,
+    BackgroundSyncRegistration::RegistrationId sync_registration_id,
+    const StatusCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  StatusCallback pending_callback =
+      base::Bind(&BackgroundSyncManager::PendingStatusCallback,
+                 weak_ptr_factory_.GetWeakPtr(), callback);
+
+  op_scheduler_.ScheduleOperation(base::Bind(
+      &BackgroundSyncManager::UnregisterImpl, weak_ptr_factory_.GetWeakPtr(),
+      origin, sw_registration_id, sync_registration_name, sync_registration_id,
+      pending_callback));
+}
+
+void BackgroundSyncManager::GetRegistration(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const std::string sync_registration_name,
+    const StatusAndRegistrationCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  StatusAndRegistrationCallback pending_callback =
+      base::Bind(&BackgroundSyncManager::PendingStatusAndRegistrationCallback,
+                 weak_ptr_factory_.GetWeakPtr(), callback);
+
+  op_scheduler_.ScheduleOperation(
+      base::Bind(&BackgroundSyncManager::GetRegistrationImpl,
+                 weak_ptr_factory_.GetWeakPtr(), origin, sw_registration_id,
+                 sync_registration_name, pending_callback));
+}
+
+BackgroundSyncManager::BackgroundSyncManager(
+    const scoped_refptr<ServiceWorkerContextWrapper>& service_worker_context)
+    : service_worker_context_(service_worker_context), weak_ptr_factory_(this) {
+}
+
+void BackgroundSyncManager::Init() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(!op_scheduler_.ScheduledOperations());
+
+  op_scheduler_.ScheduleOperation(base::Bind(&BackgroundSyncManager::InitImpl,
+                                             weak_ptr_factory_.GetWeakPtr()));
+}
+
+void BackgroundSyncManager::InitImpl() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  GetDataFromBackend(
+      kBackgroundSyncUserDataKey,
+      base::Bind(&BackgroundSyncManager::InitDidGetDataFromBackend,
+                 weak_ptr_factory_.GetWeakPtr()));
+}
+
+void BackgroundSyncManager::InitDidGetDataFromBackend(
+    const std::vector<std::pair<int64, std::string>>& user_data,
+    ServiceWorkerStatusCode status) {

[davidben, 2015/03/25 19:42:03]

Should this check status? Looks like this'll just silently drop everything if it
can't read things in. Probably should at least LOG(ERROR)? I suppose the
corruption_detected line below also just silently drops everything.

Dunno what we usually do in that case, disable the subsystem or silently try to
recover with some data loss.

[jkarlin, 2015/03/25 20:45:45]

Added a LOG error and a TODO to the header file that I need to look into error
handling from the backend.

+  bool corruption_detected = false;
+  for (const std::pair<int64, std::string>& data : user_data) {
+    BackgroundSyncRegistrationsProto registrations_proto;
+    if (registrations_proto.ParseFromString(data.second)) {
+      sw_to_registrations_map_[data.first] = BackgroundSyncRegistrations(
+          registrations_proto.next_registration_id());
+      BackgroundSyncRegistrations* registrations =
+          &sw_to_registrations_map_[data.first];
+
+      for (int i = 0, max = registrations_proto.registration_size(); i < max;
+           ++i) {
+        const BackgroundSyncRegistrationProto& registration_proto =
+            registrations_proto.registration(i);
+
+        if (registration_proto.id() >= registrations->next_id) {
+          corruption_detected = true;
+          break;
+        }
+
+        BackgroundSyncRegistration registration(registration_proto.id(),
+                                                registration_proto.name());
+        if (registration_proto.has_min_period())
+          registration.min_period = registration_proto.min_period();
+        registrations->name_to_registration_map[registration_proto.name()] =
+            registration;
+      }
+    }
+
+    if (corruption_detected)
+      break;
+  }
+
+  if (corruption_detected)

[davidben, 2015/03/25 19:42:03]

Nit: Maybe spew to LOG(ERROR) or something? Though I'm not really sure what we
do about on-disk stuff in general.

[jkarlin, 2015/03/25 20:45:45]

Done.

+    sw_to_registrations_map_.clear();
+
+  // TODO(jkarlin): Call the scheduling algorithm here.
+
+  op_scheduler_.CompleteOperationAndRunNext();
+}
+
+void BackgroundSyncManager::RegisterImpl(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& sync_registration,
+    const StatusAndRegistrationCallback& callback) {
+  BackgroundSyncRegistration existing_registration;
+  if (LookupRegistration(sw_registration_id, sync_registration.name,
+                         &existing_registration)) {
+    if (existing_registration.Equals(sync_registration)) {
+      base::MessageLoop::current()->PostTask(
+          FROM_HERE,
+          base::Bind(callback, ERROR_TYPE_OK, existing_registration));
+      return;
+    }
+  }
+
+  BackgroundSyncRegistration new_registration = sync_registration;
+  BackgroundSyncRegistrations* registrations =
+      &sw_to_registrations_map_[sw_registration_id];
+  new_registration.id = registrations->next_id++;
+
+  AddRegistrationToMap(sw_registration_id, new_registration);
+
+  StoreRegistrations(
+      origin, sw_registration_id,
+      base::Bind(&BackgroundSyncManager::RegisterDidStore,
+                 weak_ptr_factory_.GetWeakPtr(), sw_registration_id,
+                 new_registration, existing_registration, callback));
+}
+
+bool BackgroundSyncManager::LookupRegistration(
+    int64 sw_registration_id,
+    const std::string& sync_registration_name,
+    BackgroundSyncRegistration* existing_registration) {
+  SWIdToRegistrationsMap::iterator it =
+      sw_to_registrations_map_.find(sw_registration_id);
+  if (it == sw_to_registrations_map_.end())
+    return false;
+
+  const BackgroundSyncRegistrations& registrations = it->second;
+  const auto name_and_registration_iter =
+      registrations.name_to_registration_map.find(sync_registration_name);
+  if (name_and_registration_iter ==
+      registrations.name_to_registration_map.end())
+    return false;
+
+  if (existing_registration)
+    *existing_registration = name_and_registration_iter->second;
+
+  return true;
+}
+
+void BackgroundSyncManager::StoreRegistrations(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const ServiceWorkerStorage::StatusCallback& callback) {
+  // Serialize the data.
+  const BackgroundSyncRegistrations& registrations =
+      sw_to_registrations_map_[sw_registration_id];
+  BackgroundSyncRegistrationsProto registrations_proto;
+  registrations_proto.set_next_registration_id(registrations.next_id);
+
+  for (const auto& name_and_registration :
+       registrations.name_to_registration_map) {
+    const BackgroundSyncRegistration& registration =
+        name_and_registration.second;
+    BackgroundSyncRegistrationProto* registration_proto =
+        registrations_proto.add_registration();
+    registration_proto->set_id(registration.id);
+    registration_proto->set_name(registration.name);
+    if (registration.min_period != 0)
+      registration_proto->set_min_period(registration.min_period);
+  }
+  std::string serialized;
+  bool success = registrations_proto.SerializeToString(&serialized);
+  DCHECK(success);
+
+  StoreDataInBackend(sw_registration_id, origin, kBackgroundSyncUserDataKey,
+                     serialized, callback);
+}
+
+void BackgroundSyncManager::RegisterDidStore(
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& new_registration,
+    const BackgroundSyncRegistration& previous_registration,
+    const StatusAndRegistrationCallback& callback,
+    ServiceWorkerStatusCode status) {
+  if (status != SERVICE_WORKER_OK) {
+    // Restore the previous state.
+    if (previous_registration.id !=
+        BackgroundSyncRegistration::kInvalidRegistrationId) {
+      AddRegistrationToMap(sw_registration_id, previous_registration);
+    } else {
+      RemoveRegistrationFromMap(sw_registration_id, new_registration.name,
+                                nullptr);
+    }
+    base::MessageLoop::current()->PostTask(
+        FROM_HERE,
+        base::Bind(callback, ERROR_TYPE_STORAGE, BackgroundSyncRegistration()));
+    return;
+  }
+
+  // TODO(jkarlin): Run the registration algorithm.
+  base::MessageLoop::current()->PostTask(
+      FROM_HERE, base::Bind(callback, ERROR_TYPE_OK, new_registration));
+}
+
+void BackgroundSyncManager::RemoveRegistrationFromMap(
+    int64 sw_registration_id,
+    const std::string& sync_registration_name,
+    BackgroundSyncRegistration* old_registration) {
+  DCHECK(
+      LookupRegistration(sw_registration_id, sync_registration_name, nullptr));
+
+  BackgroundSyncRegistrations* registrations =
+      &sw_to_registrations_map_[sw_registration_id];
+
+  const auto name_and_registration_iter =
+      registrations->name_to_registration_map.find(sync_registration_name);
+  if (old_registration)
+    *old_registration = name_and_registration_iter->second;
+
+  registrations->name_to_registration_map.erase(name_and_registration_iter);
+}
+
+void BackgroundSyncManager::AddRegistrationToMap(
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& sync_registration) {
+  DCHECK_NE(BackgroundSyncRegistration::kInvalidRegistrationId,
+            sw_registration_id);
+
+  BackgroundSyncRegistrations* registrations =
+      &sw_to_registrations_map_[sw_registration_id];
+  registrations->name_to_registration_map[sync_registration.name] =
+      sync_registration;
+}
+
+void BackgroundSyncManager::StoreDataInBackend(
+    int64 sw_registration_id,
+    const GURL& origin,
+    const std::string& key,
+    const std::string& data,
+    const ServiceWorkerStorage::StatusCallback& callback) {
+  service_worker_context_->context()->storage()->StoreUserData(
+      sw_registration_id, origin, key, data, callback);
+}
+
+void BackgroundSyncManager::GetDataFromBackend(
+    const std::string& key,
+    const ServiceWorkerStorage::GetUserDataForAllRegistrationsCallback&
+        callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  service_worker_context_->context()->storage()->GetUserDataForAllRegistrations(
+      key, callback);
+}
+
+void BackgroundSyncManager::UnregisterImpl(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const std::string& sync_registration_name,
+    BackgroundSyncRegistration::RegistrationId sync_registration_id,
+    const StatusCallback& callback) {
+  BackgroundSyncRegistration existing_registration;
+  if (!LookupRegistration(sw_registration_id, sync_registration_name,
+                          &existing_registration) ||
+      existing_registration.id != sync_registration_id) {
+    base::MessageLoop::current()->PostTask(
+        FROM_HERE, base::Bind(callback, ERROR_TYPE_NOT_FOUND));
+    return;
+  }
+
+  BackgroundSyncRegistration old_sync_registration;
+  RemoveRegistrationFromMap(sw_registration_id, sync_registration_name,
+                            &old_sync_registration);
+
+  StoreRegistrations(
+      origin, sw_registration_id,
+      base::Bind(&BackgroundSyncManager::UnregisterDidStore,
+                 weak_ptr_factory_.GetWeakPtr(), sw_registration_id,
+                 old_sync_registration, callback));
+}
+
+void BackgroundSyncManager::UnregisterDidStore(
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& old_sync_registration,
+    const StatusCallback& callback,
+    ServiceWorkerStatusCode status) {
+  if (status != SERVICE_WORKER_OK) {
+    // Restore the previous state.
+    AddRegistrationToMap(sw_registration_id, old_sync_registration);
+    base::MessageLoop::current()->PostTask(
+        FROM_HERE, base::Bind(callback, ERROR_TYPE_STORAGE));
+    return;
+  }
+
+  // TODO(jkarlin): Run the registration algorithm.
+  base::MessageLoop::current()->PostTask(FROM_HERE,
+                                         base::Bind(callback, ERROR_TYPE_OK));
+}
+
+void BackgroundSyncManager::GetRegistrationImpl(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const std::string sync_registration_name,
+    const StatusAndRegistrationCallback& callback) {
+  BackgroundSyncRegistration out_registration;
+  if (!LookupRegistration(sw_registration_id, sync_registration_name,
+                          &out_registration)) {
+    base::MessageLoop::current()->PostTask(
+        FROM_HERE, base::Bind(callback, ERROR_TYPE_NOT_FOUND,
+                              BackgroundSyncRegistration()));
+    return;
+  }
+
+  base::MessageLoop::current()->PostTask(
+      FROM_HERE, base::Bind(callback, ERROR_TYPE_OK, out_registration));
+}
+
+void BackgroundSyncManager::PendingStatusAndRegistrationCallback(
+    const StatusAndRegistrationCallback& callback,
+    ErrorType error,
+    const BackgroundSyncRegistration& sync_registration) {
+  // The callback might delete this object, so hang onto a weak ptr to find out.
+  base::WeakPtr<BackgroundSyncManager> manager = weak_ptr_factory_.GetWeakPtr();
+  callback.Run(error, sync_registration);
+  if (manager)
+    op_scheduler_.CompleteOperationAndRunNext();
+}
+
+void BackgroundSyncManager::PendingStatusCallback(
+    const StatusCallback& callback,
+    ErrorType error) {
+  // The callback might delete this object, so hang onto a weak ptr to find out.
+  base::WeakPtr<BackgroundSyncManager> manager = weak_ptr_factory_.GetWeakPtr();
+  callback.Run(error);
+  if (manager)
+    op_scheduler_.CompleteOperationAndRunNext();
+}
+
+}  // namespace content