homescreen: Re-work gRPC client start-up

And start the gRPC client as soon as possible and just wait for
a connected status after we bounded to the agl-shell
extension/interface.

Bug-AGL: SPEC-4912
Signed-off-by: Marius Vlad <marius.vlad@collabora.com>
Change-Id: I26da89dd6aaf1b5c2357d70dcaed7622c1892c31

3 files changed, 25 insertions, 19 deletions

diff --git a/homescreen/src/AglShellGrpcClient.cpp b/homescreen/src/AglShellGrpcClient.cpp
index ee7510f..f3c72ca 100644
--- a/homescreen/src/AglShellGrpcClient.cpp
+++ b/homescreen/src/AglShellGrpcClient.cpp
@@ -25,28 +25,31 @@ namespace {
 
 GrpcClient::GrpcClient()
 {
-	struct timespec ts;
-	auto channel = grpc::CreateChannel(kDefaultGrpcServiceAddress,
+	m_channel = grpc::CreateChannel(kDefaultGrpcServiceAddress,
 			grpc::InsecureChannelCredentials());
 
+	// init the stub here
+	m_stub = agl_shell_ipc::AglShellManagerService::NewStub(m_channel);
+	reader = new Reader(m_stub.get());
+}
+
+void
+GrpcClient::WaitForConnected(int wait_time_ms, int tries_timeout)
+{
+	struct timespec ts;
+	grpc_connectivity_state state;
+	int try_ = 0;
+
 	clock_gettime(CLOCK_MONOTONIC, &ts);
 	ts.tv_sec = 0;
 	ts.tv_nsec = 500 * 1000 * 1000; // 500ms
 
-	bool try_to_connect = true;
-	grpc_connectivity_state state = channel->GetState(try_to_connect);
-
-	while (state != GRPC_CHANNEL_READY) {
-		state = channel->GetState(try_to_connect);
-
+	while (((state = m_channel->GetState(true)) != GRPC_CHANNEL_READY) && 
+		try_++ < tries_timeout) {
 		HMI_DEBUG("HomesScreen", "waiting for channel state to be ready, current state %d", state);
 		nanosleep(&ts, NULL);
 	}
 
-
-	// init the stub here
-	m_stub = agl_shell_ipc::AglShellManagerService::NewStub(channel);
-	reader = new Reader(m_stub.get());
 }
 
 
diff --git a/homescreen/src/AglShellGrpcClient.h b/homescreen/src/AglShellGrpcClient.h
index bb74377..19cfb75 100644
--- a/homescreen/src/AglShellGrpcClient.h
+++ b/homescreen/src/AglShellGrpcClient.h
@@ -92,6 +92,7 @@ private:
 class GrpcClient {
 public:
 	GrpcClient();
+	void WaitForConnected(int wait_time_ms, int tries_timeout);
 	bool ActivateApp(const std::string& app_id, const std::string& output_name);
 	bool DeactivateApp(const std::string& app_id);
 	bool SetAppFloat(const std::string& app_id, int32_t x_pos, int32_t y_pos);
@@ -108,5 +109,6 @@ public:
 private:
 	Reader *reader;
 	std::unique_ptr<agl_shell_ipc::AglShellManagerService::Stub> m_stub;
+	std::shared_ptr<grpc::Channel> m_channel;
 };
 
diff --git a/homescreen/src/main.cpp b/homescreen/src/main.cpp
index 66ddb75..ec0e1c5 100644
--- a/homescreen/src/main.cpp
+++ b/homescreen/src/main.cpp
@@ -321,8 +321,7 @@ run_in_thread(GrpcClient *client)
 
 static void
 load_agl_shell_app(QPlatformNativeInterface *native, QQmlApplicationEngine *engine,
-		   struct shell_data shell_data, const char *screen_name,
-		   bool is_demo, GrpcClient *client)
+		   struct shell_data shell_data, const char *screen_name, bool is_demo)
 {
 	QScreen *screen = nullptr;
 	HomescreenHandler *homescreenHandler = shell_data.homescreenHandler;
@@ -418,6 +417,9 @@ int main(int argc, char *argv[])
 	// we need to have an app_id
 	app.setDesktopFileName("homescreen");
 
+	GrpcClient *client = new GrpcClient();
+	// create a new thread to listner for gRPC events
+	std::thread th = std::thread(run_in_thread, client);
 
 	register_agl_shell(native, &shell_data);
 	if (!shell_data.shell) {
@@ -444,10 +446,6 @@ int main(int argc, char *argv[])
 
 	std::shared_ptr<struct agl_shell> agl_shell{shell_data.shell, agl_shell_destroy};
 
-	GrpcClient *client = new GrpcClient();
-	// create a new thread to listner for gRPC events
-	std::thread th = std::thread(run_in_thread, client);
-
 	// Import C++ class to QML
 	qmlRegisterType<StatusBarModel>("HomeScreen", 1, 0, "StatusBarModel");
 	qmlRegisterType<MasterVolume>("MasterVolume", 1, 0, "MasterVolume");
@@ -459,6 +457,9 @@ int main(int argc, char *argv[])
 	shell_data.homescreenHandler = homescreenHandler;
 	shell_data.homescreenHandler->setGrpcClient(client);
 
+	// blocks until we're sure connected with the server
+	HMI_DEBUG("HomescreenHandler", "Checking if connected to the gRPC server...");
+	client->WaitForConnected(500, 10);
 	client->AppStatusState(app_status_callback, homescreenHandler);
 
 	QQmlApplicationEngine engine;
@@ -470,7 +471,7 @@ int main(int argc, char *argv[])
 	context->setContextProperty("bluetooth", new Bluetooth(false, context));
 
 	load_agl_shell_app(native, &engine, shell_data,
-			   screen_name, is_demo_val, client);
+			   screen_name, is_demo_val);
 
 	return app.exec();
 }