bluetooth: Add control for reading/writing of characteristics to internals page.

device/bluetooth/device.cc

 // 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.
 
 #include <utility>
 #include <vector>
 
 #include "base/memory/ptr_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "device/bluetooth/device.h"
+#include "device/bluetooth/public/interfaces/gatt_result_enum_traits.h"
 #include "mojo/public/cpp/bindings/strong_binding.h"
 
+using GattResultTraits =
+    mojo::EnumTraits<bluetooth::mojom::GattResult,
+                     device::BluetoothGattService::GattErrorCode>;
+
 namespace bluetooth {
 Device::~Device() {
   adapter_->RemoveObserver(this);
 }
 
 // static
 void Device::Create(scoped_refptr<device::BluetoothAdapter> adapter,
                     std::unique_ptr<device::BluetoothGattConnection> connection,
                     mojom::DeviceRequest request) {
   auto device_impl =
@@ skipping 93 matching lines @@
     characteristic_info->id = characteristic->GetIdentifier();
     characteristic_info->uuid = characteristic->GetUUID();
     characteristic_info->properties = characteristic->GetProperties();
 
     characteristics.push_back(std::move(characteristic_info));
   }
 
   callback.Run(std::move(characteristics));
 }
 
+void Device::ReadValueForCharacteristic(
+    const std::string& service_id,
+    const std::string& characteristic_id,
+    const ReadValueForCharacteristicCallback& callback) {
+  device::BluetoothDevice* device = adapter_->GetDevice(GetAddress());
+  DCHECK(device);
+
+  device::BluetoothRemoteGattService* service =
+      device->GetGattService(service_id);
+  if (service == nullptr) {
+    callback.Run(mojom::GattResult::SERVICE_NOT_FOUND,
+                 base::nullopt /* value */);
+    return;
+  }
+
+  device::BluetoothRemoteGattCharacteristic* characteristic =
+      service->GetCharacteristic(characteristic_id);
+  if (characteristic == nullptr) {
+    callback.Run(mojom::GattResult::CHARACTERISTIC_NOT_FOUND,
+                 base::nullopt /* value */);
+    return;
+  }
+
+  characteristic->ReadRemoteCharacteristic(
+      base::Bind(&Device::OnReadRemoteCharacteristic,
+                 weak_ptr_factory_.GetWeakPtr(), callback),
+      base::Bind(&Device::OnReadRemoteCharacteristicError,
+                 weak_ptr_factory_.GetWeakPtr(), callback));
+}
+
+void Device::WriteValueForCharacteristic(
+    const std::string& service_id,
+    const std::string& characteristic_id,
+    const std::vector<uint8_t>& value,
+    const WriteValueForCharacteristicCallback& callback) {
+  device::BluetoothDevice* device = adapter_->GetDevice(GetAddress());
+  DCHECK(device);
+
+  device::BluetoothRemoteGattService* service =
+      device->GetGattService(service_id);
+  if (service == nullptr) {
+    callback.Run(mojom::GattResult::SERVICE_NOT_FOUND);
+    return;
+  }
+
+  device::BluetoothRemoteGattCharacteristic* characteristic =
+      service->GetCharacteristic(characteristic_id);
+  if (characteristic == nullptr) {
+    callback.Run(mojom::GattResult::CHARACTERISTIC_NOT_FOUND);
+    return;
+  }
+
+  characteristic->WriteRemoteCharacteristic(
+      value, base::Bind(&Device::OnWriteRemoteCharacteristic,
+                        weak_ptr_factory_.GetWeakPtr(), callback),
+      base::Bind(&Device::OnWriteRemoteCharacteristicError,
+                 weak_ptr_factory_.GetWeakPtr(), callback));
+}
+
+void Device::GetDescriptors(const std::string& service_id,
+                            const std::string& characteristic_id,
+                            const GetDescriptorsCallback& callback) {
+  device::BluetoothDevice* device = adapter_->GetDevice(GetAddress());
+  if (!device) {
+    callback.Run(base::nullopt);
+    return;
+  }
+
+  device::BluetoothRemoteGattService* service =
+      device->GetGattService(service_id);
+  if (!service) {
+    callback.Run(base::nullopt);
+    return;
+  }
+
+  device::BluetoothRemoteGattCharacteristic* characteristic =
+      service->GetCharacteristic(characteristic_id);
+  if (!characteristic) {
+    callback.Run(base::nullopt);
+    return;
+  }
+
+  std::vector<mojom::DescriptorInfoPtr> descriptors;
+
+  for (const auto* descriptor : characteristic->GetDescriptors()) {
+    mojom::DescriptorInfoPtr descriptor_info = mojom::DescriptorInfo::New();
+
+    descriptor_info->id = descriptor->GetIdentifier();
+    descriptor_info->uuid = descriptor->GetUUID();
+    descriptors.push_back(std::move(descriptor_info));
+  }
+
+  callback.Run(std::move(descriptors));
+}
+
 Device::Device(scoped_refptr<device::BluetoothAdapter> adapter,
                std::unique_ptr<device::BluetoothGattConnection> connection)
-    : adapter_(std::move(adapter)), connection_(std::move(connection)) {
+    : adapter_(std::move(adapter)),
+      connection_(std::move(connection)),
+      weak_ptr_factory_(this) {
   adapter_->AddObserver(this);
 }
 
 void Device::GetServicesImpl(const GetServicesCallback& callback) {
   device::BluetoothDevice* device = adapter_->GetDevice(GetAddress());
   DCHECK(device);
 
   std::vector<mojom::ServiceInfoPtr> services;
 
   for (const device::BluetoothRemoteGattService* service :
        device->GetGattServices()) {
     services.push_back(ConstructServiceInfoStruct(*service));
   }
 
   callback.Run(std::move(services));
 }
 
 mojom::ServiceInfoPtr Device::ConstructServiceInfoStruct(
     const device::BluetoothRemoteGattService& service) {
   mojom::ServiceInfoPtr service_info = mojom::ServiceInfo::New();
 
   service_info->id = service.GetIdentifier();
   service_info->uuid = service.GetUUID();
   service_info->is_primary = service.IsPrimary();
 
   return service_info;
 }
 
+void Device::OnReadRemoteCharacteristic(
+    const ReadValueForCharacteristicCallback& callback,
+    const std::vector<uint8_t>& value) {
+  callback.Run(mojom::GattResult::SUCCESS, std::move(value));
+}
+
+void Device::OnReadRemoteCharacteristicError(
+    const ReadValueForCharacteristicCallback& callback,
+    device::BluetoothGattService::GattErrorCode error_code) {
+  callback.Run(GattResultTraits::ToMojom(error_code),

[dcheng, 2017/01/26 19:32:25]

I think you need a typemap file as well (see the CL I linked previously): then
you can just write:

callback.Run(error_code, base::nullopt);

and it will Just Work (tm).

[mbrunson, 2017/01/26 21:27:40]

Ah...yes. The issue with that is I can't do things like this:

  callback.Run(mojom::GattResult::SERVICE_NOT_FOUND);
  callback.Run(mojom::GattResult::CHARACTERISTIC_NOT_FOUND);
  callback.Run(mojom::GattResult::SUCCESS);

with a typemap because there is no matching C++ value for this. The generated
callback only accepts the C++ version of the enum once a typemap is specified.
Adding these values to the C++ enum will require a large change to existing
code. This is what I was referring to in my original question.

+               base::nullopt /* value */);
+}
+
+void Device::OnWriteRemoteCharacteristic(
+    const WriteValueForCharacteristicCallback& callback) {
+  callback.Run(mojom::GattResult::SUCCESS);
+}
+
+void Device::OnWriteRemoteCharacteristicError(
+    const WriteValueForCharacteristicCallback& callback,
+    device::BluetoothGattService::GattErrorCode error_code) {
+  callback.Run(GattResultTraits::ToMojom(error_code));
+}
+
 const std::string& Device::GetAddress() {
   return connection_->GetDeviceAddress();
 }
 
 }  // namespace bluetooth