Service Worker: in Unregister, wait until after the active worker no longer controls a document

content/browser/service_worker/service_worker_registration.cc

 // Copyright 2013 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/service_worker/service_worker_registration.h"
 
 #include "content/browser/service_worker/service_worker_context_core.h"
 #include "content/browser/service_worker/service_worker_info.h"
 #include "content/browser/service_worker/service_worker_register_job.h"
 #include "content/browser/service_worker/service_worker_utils.h"
@@ skipping 13 matching lines @@
 
 ServiceWorkerRegistration::ServiceWorkerRegistration(
     const GURL& pattern,
     const GURL& script_url,
     int64 registration_id,
     base::WeakPtr<ServiceWorkerContextCore> context)
     : pattern_(pattern),
       script_url_(script_url),
       registration_id_(registration_id),
       is_deleted_(false),
+      is_uninstalling_(false),
       should_activate_when_ready_(false),
       context_(context) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   DCHECK(context_);
   context_->AddLiveRegistration(this);
 }
 
 ServiceWorkerRegistration::~ServiceWorkerRegistration() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   if (context_)
     context_->RemoveLiveRegistration(registration_id_);
-  ResetShouldActivateWhenReady();
+  if (should_activate_when_ready_ || is_uninstalling())
+    active_version()->RemoveListener(this);
 }
 
 void ServiceWorkerRegistration::AddListener(Listener* listener) {
   listeners_.AddObserver(listener);
 }
 
 void ServiceWorkerRegistration::RemoveListener(Listener* listener) {
   listeners_.RemoveObserver(listener);
 }
 
 ServiceWorkerRegistrationInfo ServiceWorkerRegistration::GetInfo() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   return ServiceWorkerRegistrationInfo(
       script_url(),
       pattern(),
       registration_id_,
       GetVersionInfo(active_version_),
       GetVersionInfo(waiting_version_),
       GetVersionInfo(installing_version_));
 }
 
 void ServiceWorkerRegistration::SetActiveVersion(
     ServiceWorkerVersion* version) {
-  ResetShouldActivateWhenReady();
+  SetShouldActivateWhenReady(false);
   SetVersionInternal(version, &active_version_,
                      ChangedVersionAttributesMask::ACTIVE_VERSION);
 }
 
 void ServiceWorkerRegistration::SetWaitingVersion(
     ServiceWorkerVersion* version) {
-  ResetShouldActivateWhenReady();
+  SetShouldActivateWhenReady(false);
   SetVersionInternal(version, &waiting_version_,
                      ChangedVersionAttributesMask::WAITING_VERSION);
 }
 
 void ServiceWorkerRegistration::SetInstallingVersion(
     ServiceWorkerVersion* version) {
   SetVersionInternal(version, &installing_version_,
                      ChangedVersionAttributesMask::INSTALLING_VERSION);
 }
 
@@ skipping 39 matching lines @@
   } else if (active_version_ == version) {
     active_version_ = NULL;
     mask->add(ChangedVersionAttributesMask::ACTIVE_VERSION);
   }
 }
 
 void ServiceWorkerRegistration::ActivateWaitingVersionWhenReady() {
   DCHECK(waiting_version());
   if (should_activate_when_ready_)
     return;
-  if (active_version() && active_version()->HasControllee()) {
+  if (active_version() && active_version()->HasControllee())
+    SetShouldActivateWhenReady(true);
+  else
+    ActivateWaitingVersion();
+}
+
+bool ServiceWorkerRegistration::IsListeningForNoControllees() {
+  return active_version() && (should_activate_when_ready_ || is_uninstalling_);
+}
+
+void ServiceWorkerRegistration::SetShouldActivateWhenReady(
+    bool should_activate) {
+  if (should_activate_when_ready_ == should_activate)
+    return;
+  bool listening = IsListeningForNoControllees();
+  should_activate_when_ready_ = should_activate;
+  if (listening == IsListeningForNoControllees())
+    return;
+  if (IsListeningForNoControllees())
     active_version()->AddListener(this);
-    should_activate_when_ready_ = true;
+  else
+    active_version()->RemoveListener(this);
+}

[falken, 2014/07/29 14:04:05]

It may be better for Registration to always listen to its active_version. Then
in NoControllees it always Clears() if is_uninstall is set, or activates the
waiting version if it exists. Then we don't need this bookkeeping about when to
listen.

[michaeln, 2014/07/31 00:08:07]

sgtm

+
+void ServiceWorkerRegistration::SetUninstalling(bool is_uninstalling) {
+  if (is_uninstalling_ == is_uninstalling)
     return;
-  }
-  ActivateWaitingVersion();
+  bool listening = IsListeningForNoControllees();
+  is_uninstalling_ = is_uninstalling;
+  if (listening == IsListeningForNoControllees())
+    return;
+  if (IsListeningForNoControllees())
+    active_version()->AddListener(this);
+  else
+    active_version()->RemoveListener(this);
 }
 
 void ServiceWorkerRegistration::OnNoControllees(ServiceWorkerVersion* version) {
   DCHECK_EQ(active_version(), version);
-  DCHECK(should_activate_when_ready_);
-  active_version_->RemoveListener(this);
+  active_version()->RemoveListener(this);
+  if (is_uninstalling())
+    Clear();
+  else if (should_activate_when_ready_)
+    ActivateWaitingVersion();
+  is_uninstalling_ = false;
   should_activate_when_ready_ = false;
-  ActivateWaitingVersion();
 }
 
 void ServiceWorkerRegistration::ActivateWaitingVersion() {
   DCHECK(context_);
   DCHECK(waiting_version());
   scoped_refptr<ServiceWorkerVersion> activating_version = waiting_version();
   scoped_refptr<ServiceWorkerVersion> exiting_version = active_version();
 
   if (activating_version->is_doomed() ||
       activating_version->status() == ServiceWorkerVersion::REDUNDANT) {
@@ skipping 26 matching lines @@
   activating_version->SetStatus(ServiceWorkerVersion::ACTIVATING);
 
   // TODO(nhiroki): "8. Fire a simple event named controllerchange..."
 
   // "9. Queue a task to fire an event named activate..."
   activating_version->DispatchActivateEvent(
       base::Bind(&ServiceWorkerRegistration::OnActivateEventFinished,
                  this, activating_version));
 }
 
+void ServiceWorkerRegistration::ClearWhenReady() {
+  DCHECK(context_);
+  if (is_uninstalling())
+    return;
+  context_->storage()->NotifyUninstallingRegistration(this);
+
+  // Delete from DB in case browser dies before we're ready.
+  context_->storage()->DeleteRegistration(
+      id(),
+      script_url().GetOrigin(),
+      base::Bind(&ServiceWorkerUtils::NoOpStatusCallback));
+
+  if (active_version() && active_version()->HasControllee())
+    SetUninstalling(true);
+  else
+    Clear();
+}
+
+void ServiceWorkerRegistration::AbortPendingClear() {
+  DCHECK(context_);
+  if (!is_uninstalling())
+    return;
+  SetUninstalling(false);
+  context_->storage()->NotifyDoneUninstallingRegistration(this);
+
+  if (waiting_version()) {
+    context_->storage()->StoreRegistration(
+        this,
+        waiting_version(),
+        base::Bind(&ServiceWorkerUtils::NoOpStatusCallback));
+    return;
+  }
+  if (active_version()) {
+    context_->storage()->StoreRegistration(
+        this,
+        active_version(),
+        base::Bind(&ServiceWorkerUtils::NoOpStatusCallback));
+  }
+}
+
 void ServiceWorkerRegistration::OnActivateEventFinished(
     ServiceWorkerVersion* activating_version,
     ServiceWorkerStatusCode status) {
   if (!context_ || activating_version != active_version())
     return;
   // TODO(kinuko,falken): For some error cases (e.g. ServiceWorker is
   // unexpectedly terminated) we may want to retry sending the event again.
   if (status != SERVICE_WORKER_OK) {
     // "11. If activateFailed is true, then:..."
     ServiceWorkerRegisterJob::DisassociateVersionFromDocuments(
@@ skipping 15 matching lines @@
   // "12. Run the [[UpdateState]] algorithm passing registration.activeWorker
   // and "activated" as the arguments."
   activating_version->SetStatus(ServiceWorkerVersion::ACTIVATED);
   if (context_) {
     context_->storage()->UpdateToActiveState(
         this,
         base::Bind(&ServiceWorkerUtils::NoOpStatusCallback));
   }
 }
 
-void ServiceWorkerRegistration::ResetShouldActivateWhenReady() {
-  if (should_activate_when_ready_) {
-    active_version()->RemoveListener(this);
-    should_activate_when_ready_ = false;
-  }
-}
-
 void ServiceWorkerRegistration::OnDeleteFinished(
     ServiceWorkerStatusCode status) {
   // Intentionally empty completion callback, used to prevent
   // |this| from being deleted until the storage method completes.
 }
 
+void ServiceWorkerRegistration::Clear() {
+  context_->storage()->NotifyDoneUninstallingRegistration(this);
+
+  if (installing_version()) {
+    installing_version()->Doom();
+    UnsetVersion(installing_version());
+  }
+
+  if (waiting_version()) {
+    waiting_version()->Doom();
+    UnsetVersion(waiting_version());
+  }
+
+  if (active_version()) {
+    active_version()->Doom();
+    UnsetVersion(active_version());
+  }
+}
+
 }  // namespace content