bluetooth: Move requestDevice to mojo

content/browser/bluetooth/bluetooth_device_chooser_controller.h

+// Copyright 2016 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 CONTENT_BROWSER_BLUETOOTH_BLUETOOTH_DEVICE_CHOOSER_CONTROLLER_H_
+#define CONTENT_BROWSER_BLUETOOTH_BLUETOOTH_DEVICE_CHOOSER_CONTROLLER_H_
+
+#include <string>
+
+#include "base/memory/weak_ptr.h"
+#include "base/time/time.h"
+#include "base/timer/timer.h"
+#include "content/public/browser/bluetooth_chooser.h"
+#include "third_party/WebKit/public/platform/modules/bluetooth/web_bluetooth.mojom.h"
+
+namespace device {
+class BluetoothAdapter;
+class BluetoothDevice;
+class BluetoothDiscoveryFilter;
+class BluetoothDiscoverySession;
+}
+
+namespace content {
+
+class RenderFrameHost;
+class WebContents;
+class WebBluetoothServiceImpl;
+
+// Class that interacts with a chooser and starts a bluetooth discovery session.
+// This class needs to be re-instantiated for each call to GetDevice(). Calling
+// GetDevice() twice for the same instance will DCHECK.
+class BluetoothDeviceChooserController final {
+ public:
+  typedef base::Callback<void(blink::mojom::WebBluetoothRequestDeviceOptionsPtr,
+                              const std::string& device_address)>
+      SuccessCallback;
+  typedef base::Callback<void(blink::mojom::WebBluetoothError error)>
+      ErrorCallback;
+
+  // |web_bluetooth_service_| service that owns this class.
+  // |render_frame_host| should be the RenderFrameHost that owns the
+  // |web_bluetooth_service_|.
+  // |adapter| should be the adapter used to scan for Bluetooth devices.
+  // |scan_duration| is how long will a discovery session be active.
+  BluetoothDeviceChooserController(
+      WebBluetoothServiceImpl* web_bluetooth_service_,
+      RenderFrameHost* render_frame_host,
+      device::BluetoothAdapter* adapter,
+      base::TimeDelta scan_duration);
+  ~BluetoothDeviceChooserController();
+
+  // This function performs the following checks before starting a discovery
+  // session:
+  //   - Validates filters in |request_device_options|.
+  //   - Removes any blacklisted UUIDs from
+  //     |request_device_options.optinal_services|.
+  //   - Checks if the request came from a cross-origin iframe.
+  //   - Checks if the request came from a unique origin.
+  //   - Checks if the adapter is present.
+  //   - Checks if the Web Bluetooth API has been disabled.
+  //   - Checks if we are allowed to ask for scanning permission.
+  // If any of the previous checks failed then this function runs
+  // |error_callback| with the corresponding error. Otherwise this function
+  // populates the embedder provided BluetoothChooser with existing devices and
+  // starts a new discovery session.
+  // This function should only be called once per
+  // BluetoothDeviceChooserController instance. Calling this function more than
+  // once will DCHECK.
+  void GetDevice(
+      blink::mojom::WebBluetoothRequestDeviceOptionsPtr request_device_options,
+      const SuccessCallback& success_callback,
+      const ErrorCallback& error_callback);
+
+  // Adds a device to the chooser. Should only be called after GetDevice and
+  // before either of the callbacks are run.
+  void AddFilteredDevice(const device::BluetoothDevice& device);
+
+  // Stops the current discovery session and notifies the chooser

[Jeffrey Yasskin, 2016/05/13 21:36:55]

Mhmm. Another way to do it would be to just make this class observe the adapter,
but I do see the benefit of having that all go through the
WebBluetoothServiceImpl. No need to change anything.

[ortuno, 2016/05/13 22:14:38]

Ack.

+  // that the adapter changed states.
+  void AdapterPoweredChanged(bool powered);
+
+ private:
+  // Notifies the chooser that discovery is starting and starts a discovery
+  // session.
+  void StartDeviceDiscovery();
+
+  // Stops the discovery session and notifies the chooser.
+  void StopDeviceDiscovery();
+
+  // StartDiscoverySessionWithFilter callbacks:
+  void OnStartDiscoverySessionSuccess(
+      std::unique_ptr<device::BluetoothDiscoverySession> discovery_session);
+  void OnStartDiscoverySessionFailed();
+
+  // BluetoothChooser::EventHandler:
+  // Runs error_callback_ if the chooser was cancelled or if we weren't able
+  // to show the chooser. Otherwise runs success_callback_ with
+  // |device_address|.
+  void OnBluetoothChooserEvent(BluetoothChooser::Event event,
+                               const std::string& device_address);
+
+  // Helper function to asynchronously run success_callback_.
+  void PostSuccessCallback(const std::string& device_address);
+  // Helper function to asynchronously run error_callback_.
+  void PostErrorCallback(blink::mojom::WebBluetoothError error);
+
+  // The adapter used to get existing devices and start a discovery session.
+  device::BluetoothAdapter* adapter_;
+  // The WebBluetoothServiceImpl that owns this instance.
+  WebBluetoothServiceImpl* web_bluetooth_service_;
+  // The RenderFrameHost that owns web_bluetooth_service_.
+  RenderFrameHost* render_frame_host_;
+  // The WebContents that owns render_frame_host_.
+  WebContents* web_contents_;
+
+  // Contains the filters and optional services used when scanning.
+  blink::mojom::WebBluetoothRequestDeviceOptionsPtr options_;
+
+  // Callbacks to be called with the result of the chooser.
+  SuccessCallback success_callback_;
+  ErrorCallback error_callback_;
+
+  // The currently opened BluetoothChooser.
+  std::unique_ptr<BluetoothChooser> chooser_;
+
+  // Automatically stops Bluetooth discovery a set amount of time after it was
+  // started.
+  base::Timer discovery_session_timer_;
+
+  // The last discovery session to be started.

[Jeffrey Yasskin, 2016/05/13 21:36:55]

Looking at the implementation, you do actually null it out any time we call
StopDiscoverySession() (because that's what std::move() does on a unique_ptr),
so the only ambiguity is when the system stops discovery. We should be reporting
that to the chooser anyway, so we can probably clear discovery_session_ at the
same time.

However, I don't think you need to do that now. Add a TODO for
https://crbug.com/611852?

[ortuno, 2016/05/13 22:14:38]

Done. Thanks for opening the issue!

+  std::unique_ptr<device::BluetoothDiscoverySession> discovery_session_;
+
+  // Weak pointer factory for generating 'this' pointers that might live longer
+  // than we do.
+  // Note: This should remain the last member so it'll be destroyed and
+  // invalidate its weak pointers before any other members are destroyed.
+  base::WeakPtrFactory<BluetoothDeviceChooserController> weak_ptr_factory_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_BLUETOOTH_BLUETOOTH_DEVICE_CHOOSER_CONTROLLER_H_