[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_cache_scheduler.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 {
+
+// 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(initialized_ || initializing_);
+
+  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 BackgroundSyncRegistration& sync_registration,
+    const StatusCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(initialized_ || initializing_);
+
+  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, pending_callback));
+}
+
+void BackgroundSyncManager::GetRegistration(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const std::string sync_registration_id,
+    const StatusAndRegistrationCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(initialized_ || initializing_);
+
+  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_id, pending_callback));
+}
+
+BackgroundSyncManager::BackgroundSyncManager(
+    const scoped_refptr<ServiceWorkerContextWrapper>& service_worker_context)
+    : initialized_(false),
+      initializing_(false),
+      registration_map_(new IdToRegistrationMap()),
+      op_scheduler_(new ServiceWorkerCacheScheduler()),
+      service_worker_context_(service_worker_context),
+      weak_ptr_factory_(this) {
+}
+
+void BackgroundSyncManager::Init() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(!initialized_ && !initializing_);
+  DCHECK(op_scheduler_->Empty());
+
+  initializing_ = true;
+  op_scheduler_->ScheduleOperation(base::Bind(&BackgroundSyncManager::InitImpl,
+                                              weak_ptr_factory_.GetWeakPtr()));
+}
+
+void BackgroundSyncManager::InitImpl() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(!initialized_);
+  DCHECK(initializing_);
+
+  service_worker_context_->context()->storage()->GetUserDataForAllRegistrations(
+      kBackgroundSyncUserDataKey,
+      base::Bind(&BackgroundSyncManager::InitDidGetUserData,
+                 weak_ptr_factory_.GetWeakPtr()));
+}
+
+void BackgroundSyncManager::InitDidGetUserData(
+    const std::vector<std::pair<int64, std::string>>& user_data,
+    ServiceWorkerStatusCode status) {
+  for (const std::pair<int64, std::string>& data : user_data) {
+    BackgroundSyncRegistrationsProto registrations_proto;
+    if (registrations_proto.ParseFromString(data.second)) {
+      for (int i = 0, max = registrations_proto.registration_size(); i < max;
+           ++i) {
+        const BackgroundSyncRegistrationProto& registration_proto =
+            registrations_proto.registration(i);
+        (*registration_map_)[data.first].push_back(
+            BackgroundSyncRegistration(registration_proto.id()));
+      }
+    }
+  }
+
+  initializing_ = false;
+  initialized_ = true;
+
+  // 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) {
+  // TODO(jkarlin): Check for permission.

[davidben, 2015/03/13 22:05:43]

(Seems an important thing to do. :-P)

[jkarlin, 2015/03/14 01:17:27]

Yes, though we're protected by (two) command line flags.

+
+  if (!AddRegistrationToMap(sw_registration_id, sync_registration)) {
+    callback.Run(ErrorTypeExists, BackgroundSyncRegistration(""));

[davidben, 2015/03/13 22:05:43]

Between this and everyone futher up the stack, it looks like all this makes
Register possible to run its callback reentrantly. It might be better to pop
them to the message loop one iteration. At a glance, ServiceWorkerStorage has a
RunSoon, so there's some precedence in SW code to do this. (Otherwise you end up
potentially deeply nesting functions on the stack. //net functions can return
synchronously to avoid this. When they can't, they pop to the message loop.)

(Ditto for the other callback.Runs, although probably not all make the public
APIs reentrant.)

[jkarlin, 2015/03/14 01:17:27]

RunSoon is a good idea, done.

+    return;
+  }
+
+  StoreRegistrations(
+      origin, sw_registration_id,
+      base::Bind(&BackgroundSyncManager::RegisterDidStore,
+                 weak_ptr_factory_.GetWeakPtr(), sw_registration_id,
+                 sync_registration, callback));
+}
+
+bool BackgroundSyncManager::HasRegistration(
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& sync_registration) {
+  IdToRegistrationMap::iterator it =
+      registration_map_->find(sw_registration_id);
+  if (it == registration_map_->end())
+    return false;
+
+  for (const BackgroundSyncRegistration& reg : it->second) {
+    if (sync_registration.id == reg.id)
+      return true;
+  }
+  return false;
+}
+
+void BackgroundSyncManager::StoreRegistrations(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const ServiceWorkerStorage::StatusCallback& callback) {
+  // Serialize the data.
+  BackgroundSyncRegistrationsProto registrations_proto;
+  for (const BackgroundSyncRegistration& sync_registration :
+       (*registration_map_)[sw_registration_id]) {
+    BackgroundSyncRegistrationProto* registration_proto =
+        registrations_proto.add_registration();
+    registration_proto->set_id(sync_registration.id);
+  }

[davidben, 2015/03/13 22:05:43]

Writing N registrations takes O(N^2). Is this a problem for what you're planning
on doing?

[jkarlin, 2015/03/14 01:17:27]

The thought is that the lists will be small.  In which case a list makes more
sense than a map or hash table. But one never knows, I'm sure there will be
strange pages out there. I'll stick with a list for now but consider a map
later.

+  std::string serialized;
+  bool success = registrations_proto.SerializeToString(&serialized);
+  DCHECK(success);
+
+  // Store it.
+  service_worker_context_->context()->storage()->StoreUserData(
+      sw_registration_id, origin, kBackgroundSyncUserDataKey, serialized,
+      callback);
+}
+
+void BackgroundSyncManager::RegisterDidStore(
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& sync_registration,
+    const StatusAndRegistrationCallback& callback,
+    ServiceWorkerStatusCode status) {
+  if (status != SERVICE_WORKER_OK) {
+    // Restore the previous state.
+    RemoveRegistrationFromMap(sw_registration_id, sync_registration);
+    callback.Run(ErrorTypeStorage, BackgroundSyncRegistration());
+    return;
+  }
+  // TODO(jkarlin): Run the registration algorithm.
+  callback.Run(ErrorTypeOK, sync_registration);
+}
+
+bool BackgroundSyncManager::RemoveRegistrationFromMap(
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& sync_registration) {
+  IdToRegistrationMap::iterator it =
+      registration_map_->find(sw_registration_id);
+
+  if (it == registration_map_->end())
+    return false;
+
+  std::list<BackgroundSyncRegistration>* registrations = &(it->second);
+  for (std::list<BackgroundSyncRegistration>::iterator reg_iter =
+           registrations->begin();
+       reg_iter != registrations->end(); ++reg_iter) {
+    if (reg_iter->id == sync_registration.id) {
+      registrations->erase(reg_iter);
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool BackgroundSyncManager::AddRegistrationToMap(
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& sync_registration) {
+  if (HasRegistration(sw_registration_id, sync_registration))
+    return false;
+
+  (*registration_map_)[sw_registration_id].push_back(sync_registration);
+  return true;
+}
+
+void BackgroundSyncManager::UnregisterImpl(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& sync_registration,
+    const StatusCallback& callback) {
+  if (!RemoveRegistrationFromMap(sw_registration_id, sync_registration)) {
+    callback.Run(ErrorTypeNotFound);
+    return;
+  }
+
+  StoreRegistrations(
+      origin, sw_registration_id,
+      base::Bind(&BackgroundSyncManager::UnregisterDidStore,
+                 weak_ptr_factory_.GetWeakPtr(), sw_registration_id,
+                 sync_registration, callback));
+}
+
+void BackgroundSyncManager::UnregisterDidStore(
+    int64 sw_registration_id,
+    const BackgroundSyncRegistration& sync_registration,
+    const StatusCallback& callback,
+    ServiceWorkerStatusCode status) {
+  if (status != SERVICE_WORKER_OK) {
+    // Restore the previous state.
+    AddRegistrationToMap(sw_registration_id, sync_registration);
+    callback.Run(ErrorTypeStorage);
+    return;
+  }
+
+  // TODO(jkarlin): Run the registration algorithm.
+  callback.Run(ErrorTypeOK);
+}
+
+void BackgroundSyncManager::GetRegistrationImpl(
+    const GURL& origin,
+    int64 sw_registration_id,
+    const std::string sync_registration_id,
+    const StatusAndRegistrationCallback& callback) {
+  IdToRegistrationMap::iterator it =
+      registration_map_->find(sw_registration_id);
+
+  if (it == registration_map_->end()) {
+    callback.Run(ErrorTypeNotFound, BackgroundSyncRegistration());
+    return;
+  }
+
+  std::list<BackgroundSyncRegistration>* registrations = &(it->second);
+  for (std::list<BackgroundSyncRegistration>::iterator reg_iter =
+           registrations->begin();
+       reg_iter != registrations->end(); ++reg_iter) {

[davidben, 2015/03/13 22:05:43]

for-each loop?

[jkarlin, 2015/03/14 01:17:27]

Done.

+    if (reg_iter->id == sync_registration_id) {
+      callback.Run(ErrorTypeOK, *reg_iter);
+      return;
+    }
+  }
+
+  callback.Run(ErrorTypeNotFound, BackgroundSyncRegistration());
+}
+
+void BackgroundSyncManager::PendingStatusAndRegistrationCallback(
+    const StatusAndRegistrationCallback& callback,
+    ErrorType error,
+    const BackgroundSyncRegistration& sync_registration) {
+  base::WeakPtr<BackgroundSyncManager> manager = weak_ptr_factory_.GetWeakPtr();

[davidben, 2015/03/13 22:05:43]

Worth a comment explaining what's going on here? (That you're worried about the
callback destroying the BackgroundSyncManager.)

Actually, I could believe that whatever the solution for the reentrancy problem
above turns out to be would make some of this moot.

[jkarlin, 2015/03/14 01:17:27]

Added comments. The callback is from outside of this object, and it may still
delete this object. So it's a good idea to keep the check.

+  callback.Run(error, sync_registration);
+  if (manager)
+    op_scheduler_->CompleteOperationAndRunNext();
+}
+
+void BackgroundSyncManager::PendingStatusCallback(
+    const StatusCallback& callback,
+    ErrorType error) {
+  base::WeakPtr<BackgroundSyncManager> manager = weak_ptr_factory_.GetWeakPtr();
+  callback.Run(error);
+  if (manager)
+    op_scheduler_->CompleteOperationAndRunNext();
+}
+
+}  // namespace content