Remove RemoteServerDisconnect() from web_bluetooth.mojom

third_party/WebKit/Source/modules/bluetooth/BluetoothRemoteGATTServer.cpp

 // 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 "modules/bluetooth/BluetoothRemoteGATTServer.h"
 
 #include "bindings/core/v8/CallbackPromiseAdapter.h"
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
 #include "core/dom/DOMException.h"
@@ skipping 19 matching lines @@
     ExecutionContext* context,
     BluetoothDevice* device) {
   return new BluetoothRemoteGATTServer(context, device);
 }
 
 void BluetoothRemoteGATTServer::contextDestroyed(ExecutionContext*) {
   Dispose();
 }
 
 void BluetoothRemoteGATTServer::GATTServerDisconnected() {
-  DispatchDisconnected();
+  // This function can only be called if |m_clientBinding| is bound and
+  // |m_clientBinding| can only be bound if |m_connected| is true.
+  // Therefore we skip Step 2 of Responding to Disconnection.
+  // https://webbluetoothcg.github.io/web-bluetooth/#disconnection-events
+  DCHECK(m_clientBinding.is_bound());
+  CleanupDisconnectedDevice(true /* dispatchEvent */);
 }
 
 void BluetoothRemoteGATTServer::AddToActiveAlgorithms(
     ScriptPromiseResolver* resolver) {
   auto result = m_activeAlgorithms.insert(resolver);
   CHECK(result.isNewEntry);
 }
 
 bool BluetoothRemoteGATTServer::RemoveFromActiveAlgorithms(
     ScriptPromiseResolver* resolver) {
   if (!m_activeAlgorithms.contains(resolver)) {
     return false;
   }
   m_activeAlgorithms.erase(resolver);
   return true;
 }
 
-void BluetoothRemoteGATTServer::DisconnectIfConnected() {
-  if (m_connected) {
-    SetConnected(false);
-    ClearActiveAlgorithms();
-    mojom::blink::WebBluetoothService* service =
-        m_device->bluetooth()->Service();
-    service->RemoteServerDisconnect(m_device->id());
+void BluetoothRemoteGATTServer::CleanupDisconnectedDevice(bool dispatchEvent) {

[scheib, 2017/03/22 01:11:08]

ortuno reminds us that this implementation is intended to follow
https://webbluetoothcg.github.io/web-bluetooth/#clean-up-the-disconnected-device.


Please add a comment on this implementation to make that clear

// This implements the specification "clean up the disconnected device"
algorithm 
//
https://webbluetoothcg.github.io/web-bluetooth/#clean-up-the-disconnected-device

I think it is warranted in both declaration and here in definition because it's
being used in a very specific way.

[juncai, 2017/03/27 20:44:46]

Done.

+  DCHECK(m_connected);
+  SetConnected(false);
+  ClearActiveAlgorithms();
+  m_device->ClearAttributeInstanceMap();

[scheib, 2017/03/22 01:11:08]

Below this line there are steps in the specification which we are not explicitly
handling here (clearing representedService, notification & indications). We
should comment here explaining why no explicit actions are needed. OK to mark
this as a TODO and follow up.

[juncai, 2017/03/27 20:44:46]

Done.

+  if (dispatchEvent) {
+    m_device->dispatchEvent(
+        Event::createBubble(EventTypeNames::gattserverdisconnected));
   }
 }
 
-void BluetoothRemoteGATTServer::CleanupDisconnectedDeviceAndFireEvent() {
-  DCHECK(m_connected);
-  SetConnected(false);
-  ClearActiveAlgorithms();
-  m_device->ClearAttributeInstanceMapAndFireEvent();
-}
-
-void BluetoothRemoteGATTServer::DispatchDisconnected() {
+void BluetoothRemoteGATTServer::HandleClientConnectionError() {
   if (!m_connected) {
     return;
   }
-  CleanupDisconnectedDeviceAndFireEvent();
+  CleanupDisconnectedDevice(true /* dispatchEvent */);
 }
 
 void BluetoothRemoteGATTServer::Dispose() {
-  DisconnectIfConnected();
-  // The pipe to this object must be closed when is marked unreachable to
-  // prevent messages from being dispatched before lazy sweeping.
+  if (!m_connected) {
+    return;
+  }
+  // The object is being garbage collected or the context is being destroyed,
+  // so no need to dispatch a gattserverdisconnected event.
+  CleanupDisconnectedDevice(false /* dispatchEvent */);

[scheib, 2017/03/22 01:11:08]

Thanks! So much clearer.

+  DCHECK(m_clientBinding.is_bound());
   m_clientBinding.Close();
 }
 
 DEFINE_TRACE(BluetoothRemoteGATTServer) {
   visitor->trace(m_activeAlgorithms);
   visitor->trace(m_device);
   ContextLifecycleObserver::trace(visitor);
 }
 
 void BluetoothRemoteGATTServer::ConnectCallback(
@@ skipping 11 matching lines @@
   }
 }
 
 ScriptPromise BluetoothRemoteGATTServer::connect(ScriptState* scriptState) {
   ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
   ScriptPromise promise = resolver->promise();
 
   mojom::blink::WebBluetoothService* service = m_device->bluetooth()->Service();
   mojom::blink::WebBluetoothServerClientAssociatedPtrInfo ptrInfo;
   m_clientBinding.Bind(&ptrInfo);
+  m_clientBinding.set_connection_error_handler(convertToBaseCallback(
+      WTF::bind(&BluetoothRemoteGATTServer::HandleClientConnectionError,
+                wrapWeakPersistent(this))));
   service->RemoteServerConnect(
       m_device->id(), std::move(ptrInfo),
       convertToBaseCallback(
           WTF::bind(&BluetoothRemoteGATTServer::ConnectCallback,
                     wrapPersistent(this), wrapPersistent(resolver))));
 
   return promise;
 }
 
 void BluetoothRemoteGATTServer::disconnect(ScriptState* scriptState) {
-  if (!m_connected)
+  ClearActiveAlgorithms();
+  if (!m_connected) {
     return;
-  CleanupDisconnectedDeviceAndFireEvent();
+  }
+  CleanupDisconnectedDevice(true /* dispatchEvent */);
+  DCHECK(m_clientBinding.is_bound());
   m_clientBinding.Close();

[scheib, 2017/03/22 01:11:08]

It now becomes less clear how we are signaling to the WBService that disconnect
should happen. Perhaps a short comment here, or less so on the member
m_clientBinding.

// Implicitly signals disconnect via the connection_error_handler

[juncai, 2017/03/27 20:44:46]

Done.

-  mojom::blink::WebBluetoothService* service = m_device->bluetooth()->Service();
-  service->RemoteServerDisconnect(m_device->id());
 }
 
 // Callback that allows us to resolve the promise with a single service or
 // with a vector owning the services.
 void BluetoothRemoteGATTServer::GetPrimaryServicesCallback(
     const String& requestedServiceUUID,
     mojom::blink::WebBluetoothGATTQueryQuantity quantity,
     ScriptPromiseResolver* resolver,
     mojom::blink::WebBluetoothResult result,
     Optional<Vector<mojom::blink::WebBluetoothRemoteGATTServicePtr>> services) {
@@ skipping 90 matching lines @@
   service->RemoteServerGetPrimaryServices(
       m_device->id(), quantity, servicesUUID,
       convertToBaseCallback(
           WTF::bind(&BluetoothRemoteGATTServer::GetPrimaryServicesCallback,
                     wrapPersistent(this), servicesUUID, quantity,
                     wrapPersistent(resolver))));
   return promise;
 }
 
 }  // namespace blink