GODT-2108: implement C++ Focus gRPC service client in bridge-gui.

internal/frontend/bridge-gui/bridgepp/bridgepp/FocusGRPC/FocusGRPCClient.cpp

@@ -0,0 +1,101 @@
+// Copyright (c) 2022 Proton AG
+//
+// This file is part of Proton Mail Bridge.
+//
+// Proton Mail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail Bridge. If not, see <https://www.gnu.org/licenses/>.
+
+
+#include "FocusGRPCClient.h"
+#include "../Exception/Exception.h"
+
+
+using namespace focus;
+using namespace grpc;
+using namespace google::protobuf;
+
+
+namespace
+{
+
+
+Empty empty; ///< Empty protobuf message, re-used across calls.
+qint64 const port = 1042; ///< The port for the focus service.
+QString const hostname = "127.0.0.1"; ///< The hostname of the focus service.
+
+
+}
+
+
+namespace bridgepp
+{
+
+
+//****************************************************************************************************************************************************
+/// \param[in] timeoutMs The timeout for the connexion.
+/// \param[out] outError if not null and the function returns false.
+/// \return true iff the connexion was successfully established.
+//****************************************************************************************************************************************************
+bool FocusGRPCClient::connectToServer(qint64 timeoutMs, QString *outError)
+{
+    try
+    {
+        QString const address = QString("%1:%2").arg(hostname).arg(port);
+        channel_ = grpc::CreateChannel(address.toStdString(), grpc::InsecureChannelCredentials());
+        if (!channel_)
+            throw Exception("Could not create focus service channel.");
+        stub_ = Focus::NewStub(channel_);
+
+        if (!channel_->WaitForConnected(gpr_time_add(gpr_now(GPR_CLOCK_REALTIME), gpr_time_from_millis(timeoutMs, GPR_TIMESPAN))))
+            throw Exception("Could not connect to focus service");
+
+        if (channel_->GetState(true) != GRPC_CHANNEL_READY)
+            throw Exception("Connexion check with focus service failed.");
+
+        return true;
+    }
+    catch (Exception const &e)
+    {
+        if (outError)
+            *outError = e.qwhat();
+        return false;
+    }
+}
+
+
+//****************************************************************************************************************************************************
+/// \return The status for the call.
+//****************************************************************************************************************************************************
+grpc::Status FocusGRPCClient::raise()
+{
+    ClientContext ctx;
+    return stub_->Raise(&ctx, empty, &empty);
+}
+
+
+//****************************************************************************************************************************************************
+/// \param[out] outVersion The version string.
+/// \return The status for the call.
+//****************************************************************************************************************************************************
+grpc::Status FocusGRPCClient::version(QString &outVersion)
+{
+    ClientContext ctx;
+    VersionResponse response;
+    Status status = stub_->Version(&ctx, empty, &response);
+    if (status.ok())
+        outVersion = QString::fromStdString(response.version());
+    return status;
+}
+
+
+}// namespace bridgepp