Implement a Mojo service for Background Fetch

third_party/WebKit/Source/modules/background_fetch/BackgroundFetchBridge.h

+// Copyright 2017 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.
+
+#ifndef BackgroundFetchBridge_h
+#define BackgroundFetchBridge_h
+
+#include <memory>
+#include "modules/serviceworkers/ServiceWorkerRegistration.h"
+#include "platform/Supplementable.h"
+#include "platform/heap/Handle.h"
+#include "public/platform/modules/background_fetch/background_fetch.mojom-blink.h"
+#include "wtf/Functional.h"
+#include "wtf/Vector.h"
+#include "wtf/text/WTFString.h"
+
+namespace blink {
+
+class BackgroundFetchRegistration;
+
+// The bridge is responsible for establishing and maintaining the Mojo
+// connection to the BackgroundFetchService. It's keyed on an active Service
+// Worker Registration.
+class BackgroundFetchBridge final
+    : public GarbageCollectedFinalized<BackgroundFetchBridge>,
+      public Supplement<ServiceWorkerRegistration> {
+  USING_GARBAGE_COLLECTED_MIXIN(BackgroundFetchBridge);
+  WTF_MAKE_NONCOPYABLE(BackgroundFetchBridge);
+
+ public:
+  using UpdateUICallback = Function<void(mojom::blink::BackgroundFetchError)>;
+  using GetRegistrationCallback =
+      Function<void(mojom::blink::BackgroundFetchError,
+                    BackgroundFetchRegistration*)>;
+  using GetTagsCallback =
+      Function<void(mojom::blink::BackgroundFetchError, const Vector<String>&)>;
+
+  static BackgroundFetchBridge* from(ServiceWorkerRegistration*);
+  static const char* supplementName();
+
+  virtual ~BackgroundFetchBridge();
+
+  // TODO(peter): Implement suppor for the `fetch()` function in the bridge.

[haraken, 2017/03/14 09:13:14]

support

[Peter Beverloo, 2017/03/14 15:17:21]

Done.

+
+  // Updates the user interface for the Background Fetch identified by |tag|
+  // with the updated |title|. Will invoke the |callback| when the interface
+  // has been updated.

[harkness, 2017/03/14 11:55:47]

Can we give a weaker time guarantee for this? Instead just say that callback is
invoked when the UI has been told to update and when queries of the UI would
return the updated title?

[Peter Beverloo, 2017/03/14 15:17:21]

Done.

+  void updateUI(const String& tag,
+                const String& title,
+                std::unique_ptr<UpdateUICallback>);
+
+  // Aborts the active Background Fetch for |tag|. Does not respond.
+  void abort(const String& tag);
+
+  // Gets the Background Fetch registration for the given |tag|. Will invoke the
+  // |callback| with the Background Fetch registration, which may be a nullptr
+  // if the |tag| does not exist, when the Mojo call has completed.
+  void getRegistration(const String& tag,
+                       std::unique_ptr<GetRegistrationCallback>);
+
+  // Gets the sequence of tags for active Background Fetch registrations. Will
+  // invoke the |callback| with the tags when the Mojo call has completed.
+  void getTags(std::unique_ptr<GetTagsCallback>);
+
+ private:
+  explicit BackgroundFetchBridge(ServiceWorkerRegistration&);
+
+  // Returns an initialized BackgroundFetchServicePtr. A connection will be
+  // established after the first call to this method.
+  const mojom::blink::BackgroundFetchServicePtr& GetService();
+
+  void didGetRegistration(std::unique_ptr<GetRegistrationCallback>,
+                          mojom::blink::BackgroundFetchError,
+                          mojom::blink::BackgroundFetchRegistrationPtr);
+
+  mojom::blink::BackgroundFetchServicePtr m_backgroundFetchService;
+};
+
+}  // namespace blink
+
+#endif  // BackgroundFetchBridge_h