Rework vehicle signals support to use KUKSA.val databroker

Rework the VehicleSignals class and its use in the Navigation and
Hvac classes to switch from using the original KUKSA.val server
via WebSockets to the KUKSA.val databroker's gRPC "VAL" API.

Notable changes:
- The VehicleSignals API has changed a bit with respect to setting
  signals, callers now need to pass the new value as the type that
  matches the signal as opposed to always passing a string, and
  optionally indicate if an actuator's target or value is being set.
  Subscribe operations now also allow subscribing for either
  actuator targets or values.
- It is possible that the values returned by get and subscribe
  operations will be changed to using QVariant instead of QStrings
  in a future follow up, but that has not been done in these changes.
- The connected signal from VehicleSignals still has roughly the
  same meaning, but the authorize function and authorized signals
  are to some degree redundant now.  They have been kept for
  compatibility, but may be removed in a follow up set of changes.
- The section header in the .ini files expected by the
  VehicleSignalsConfig class has been changed from "vis-client" to
  "kuksa-client" since the databroker is not a VIS server, and to
  some degree forcing an update on the part of clients is useful
  since their authorization tokens also need to change.
- The client key and certificate support has been removed from the
  VehicleSignalsConfig class, as they are no longer used in either
  the server or databroker as of KUKSA.val 0.4.0.  A new optional
  parameter, "tls-server-name", has been added to work with the new
  TLS support behavior.  It can be used to override the expected
  host name for connecting to a non-local databroker instance.
- The Navigation constructor now takes an additional parameter to
  indicate whether the instance acts as a router or a client.
  The underlying need for this stems from an application acting as
  a router needing to subscribe to the destination setting actuator
  targets.

Bug-AGL: SPEC-4762

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: I253480ae2abf068dc6e41a495454960ed5c0feaf

13 files changed, 990 insertions, 545 deletions

diff --git a/hvac/hvac.cpp b/hvac/hvac.cpp
index 246fa63..63ba5cf 100644
--- a/hvac/hvac.cpp
+++ b/hvac/hvac.cpp
@@ -29,8 +29,6 @@ HVAC::HVAC(VehicleSignals *vs, QObject * parent) :
 	m_temp_right_zone(21)
 {
 	QObject::connect(m_vs, &VehicleSignals::connected, this, &HVAC::onConnected);
-	QObject::connect(m_vs, &VehicleSignals::authorized, this, &HVAC::onAuthorized);
-	QObject::connect(m_vs, &VehicleSignals::disconnected, this, &HVAC::onDisconnected);
 
 	if (m_vs)
 		m_vs->connect();
@@ -48,7 +46,7 @@ void HVAC::set_fanspeed(int speed)
 
 	// Scale incoming 0-255 speed to 0-100 to match VSS signal
 	double value = (speed % 256) * 100.0 / 255.0;
-	m_vs->set("Vehicle.Cabin.HVAC.Station.Row1.Left.FanSpeed", QString::number((int) (value + 0.5)));
+	m_vs->set("Vehicle.Cabin.HVAC.Station.Row1.Left.FanSpeed", (unsigned int) (value + 0.5), true);
 	emit fanSpeedChanged(speed);
 }
 
@@ -63,7 +61,7 @@ void HVAC::set_temp_left_zone(int temp)
 		value = 50;
 	else if (value < -50)
 		value = -50;
-	m_vs->set("Vehicle.Cabin.HVAC.Station.Row1.Left.Temperature", QString::number(value));
+	m_vs->set("Vehicle.Cabin.HVAC.Station.Row1.Left.Temperature", value, true);
 	emit leftTemperatureChanged(temp);
 }
 
@@ -78,7 +76,7 @@ void HVAC::set_temp_right_zone(int temp)
 		value = 50;
 	else if (value < -50)
 		value = -50;
-	m_vs->set("Vehicle.Cabin.HVAC.Station.Row1.Right.Temperature", QString::number(value));
+	m_vs->set("Vehicle.Cabin.HVAC.Station.Row1.Right.Temperature", value, true);
 	emit rightTemperatureChanged(temp);
 }
 
@@ -87,21 +85,8 @@ void HVAC::onConnected()
 	if (!m_vs)
 		return;
 
-	m_vs->authorize();
-}
-
-void HVAC::onAuthorized()
-{
-	if (!m_vs)
-		return;
-
 	// Could subscribe and connect notification signal here to monitor
 	// external updates...
 
 	m_connected = true;
 }
-
-void HVAC::onDisconnected()
-{
-	m_connected = false;
-}
diff --git a/hvac/hvac.h b/hvac/hvac.h
index 34530fa..12c84fb 100644
--- a/hvac/hvac.h
+++ b/hvac/hvac.h
@@ -45,8 +45,6 @@ signals:
 
 private slots:
 	void onConnected();
-	void onAuthorized();
-	void onDisconnected();
 
 private:
 	VehicleSignals *m_vs;
diff --git a/meson.build b/meson.build
index eb52859..263d3d5 100644
--- a/meson.build
+++ b/meson.build
@@ -19,7 +19,7 @@ project (
   ['cpp'],
   version : '2.0.1',
   license : 'Apache-2.0',
-  meson_version : '>= 0.46.0',
+  meson_version : '>= 0.49.0',
   default_options :
     [
       'warning_level=1',
diff --git a/meson_options.txt b/meson_options.txt
new file mode 100644
index 0000000..1fe219e
--- /dev/null
+++ b/meson_options.txt
@@ -0,0 +1 @@
+option('protos', type : 'string', value : '/usr/include', description : 'Include directory for .proto files')
diff --git a/navigation/navigation.cpp b/navigation/navigation.cpp
index cb9f6cd..a39684f 100644
--- a/navigation/navigation.cpp
+++ b/navigation/navigation.cpp
@@ -1,33 +1,23 @@
 /*
- * Copyright (C) 2019-2022 Konsulko Group
+ * Copyright (C) 2019-2023 Konsulko Group
  *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * SPDX-License-Identifier: Apache-2.0
  */
 
 #include <QDebug>
+#include <math.h>
 
 #include "navigation.h"
 #include "vehiclesignals.h"
 
-Navigation::Navigation(VehicleSignals *vs, QObject * parent) :
-	QObject(parent),
-	m_vs(vs),
-	m_connected(false)
+#define ROUND9(x) (round((x) * 1000000000) / 1000000000)
 
+Navigation::Navigation(VehicleSignals *vs, bool router, QObject * parent) :
+	m_vs(vs),
+	m_router(router),
+	QObject(parent)
 {
 	QObject::connect(m_vs, &VehicleSignals::connected, this, &Navigation::onConnected);
-	QObject::connect(m_vs, &VehicleSignals::authorized, this, &Navigation::onAuthorized);
-	QObject::connect(m_vs, &VehicleSignals::disconnected, this, &Navigation::onDisconnected);
 
 	if (m_vs)
 		m_vs->connect();
@@ -40,7 +30,7 @@ Navigation::~Navigation()
 
 void Navigation::sendWaypoint(double lat, double lon)
 {
-	if (!(m_vs && m_connected))
+	if (!(m_vs && m_connected && m_router))
 		return;
 
 	// The original implementation resulted in at least 9 decimal places
@@ -48,18 +38,18 @@ void Navigation::sendWaypoint(double lat, double lon)
 	// practice going from the QString default 6 to 9 does make a difference
 	// with respect to smoothness in the position-based map rotations done
 	// in tbtnavi.
-	m_vs->set("Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Latitude", QString::number(lat, 'f', 9));
-	m_vs->set("Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Longitude", QString::number(lon, 'f', 9));
+	m_vs->set("Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Latitude", lat);
+	m_vs->set("Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Longitude", lon);
 }
 
 void Navigation::broadcastPosition(double lat, double lon, double drc, double dst)
 {
-	if (!(m_vs && m_connected))
+	if (!(m_vs && m_connected && m_router))
 		return;
 
-	m_vs->set("Vehicle.CurrentLocation.Latitude", QString::number(lat, 'f', 9));
-	m_vs->set("Vehicle.CurrentLocation.Longitude", QString::number(lon, 'f', 9));
-	m_vs->set("Vehicle.CurrentLocation.Heading", QString::number(drc, 'f', 9));
+	m_vs->set("Vehicle.CurrentLocation.Latitude", lat);
+	m_vs->set("Vehicle.CurrentLocation.Longitude", lon);
+	m_vs->set("Vehicle.CurrentLocation.Heading", drc);
 
 	// NOTES:
 	// - This signal is an AGL addition, it may make sense to engage with the
@@ -67,24 +57,24 @@ void Navigation::broadcastPosition(double lat, double lon, double drc, double ds
 	// - The signal makes more sense in kilometers wrt VSS expectations, so
 	//   conversion from meters happens here for now to avoid changing the
 	//   existing clients.  This may be worth revisiting down the road.
-	m_vs->set("Vehicle.Cabin.Infotainment.Navigation.ElapsedDistance", QString::number(dst / 1000, 'f', 9));
+	m_vs->set("Vehicle.Cabin.Infotainment.Navigation.ElapsedDistance", (float) (dst / 1000));
 }
 
 void Navigation::broadcastRouteInfo(double lat, double lon, double route_lat, double route_lon)
 {
-	if (!(m_vs && m_connected))
+	if (!(m_vs && m_connected && m_router))
 		return;
 
-	m_vs->set("Vehicle.CurrentLocation.Latitude", QString::number(lat, 'f', 9));
-	m_vs->set("Vehicle.CurrentLocation.Longitude", QString::number(lon, 'f', 9));
+	m_vs->set("Vehicle.CurrentLocation.Latitude", lat);
+	m_vs->set("Vehicle.CurrentLocation.Longitude", lon);
 
-	m_vs->set("Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Latitude", QString::number(route_lat, 'f', 9));
-	m_vs->set("Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Longitude", QString::number(route_lon, 'f', 9));
+	m_vs->set("Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Latitude", route_lat, true);
+	m_vs->set("Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Longitude", route_lon, true);
 }
 
 void Navigation::broadcastStatus(QString state)
 {
-	if (!(m_vs && m_connected))
+	if (!(m_vs && m_connected && m_router))
 		return;
 
 	// The signal states have been changed to all uppercase to match
@@ -97,58 +87,121 @@ void Navigation::onConnected()
 	if (!m_vs)
 		return;
 
-	m_vs->authorize();
-}
-
-void Navigation::onAuthorized()
-{
-	if (!m_vs)
-		return;
-
 	m_connected = true;
 
-	QObject::connect(m_vs, &VehicleSignals::signalNotification, this, &Navigation::onSignalNotification);
+	if (m_router) {
+		qInfo() << "Connected as router";
+		QObject::connect(m_vs, &VehicleSignals::signalNotification, this, &Navigation::onSignalNotificationRouter);
+	} else {
+		QObject::connect(m_vs, &VehicleSignals::signalNotification, this, &Navigation::onSignalNotification);
+	}
 
 	// NOTE: This signal is another AGL addition where it is possible
 	//       upstream may be open to adding it to VSS.
-	m_vs->subscribe("Vehicle.Cabin.Infotainment.Navigation.State");
-	m_vs->subscribe("Vehicle.CurrentLocation.Latitude");
-	m_vs->subscribe("Vehicle.CurrentLocation.Longitude");
-	m_vs->subscribe("Vehicle.CurrentLocation.Heading");
-	m_vs->subscribe("Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Latitude");
-	m_vs->subscribe("Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Longitude");
-	m_vs->subscribe("Vehicle.Cabin.Infotainment.Navigation.ElapsedDistance");
-}
-
-void Navigation::onDisconnected()
-{
-	QObject::disconnect(m_vs, &VehicleSignals::signalNotification, this, &Navigation::onSignalNotification);
-
-	m_connected = false;
+	QMap<QString, bool> s;
+	s["Vehicle.Cabin.Infotainment.Navigation.State"] = false;
+	if (!m_router) {
+		// Router broadcasts these signals and does not need to listen to them
+		s["Vehicle.CurrentLocation.Latitude"] = false;
+		s["Vehicle.CurrentLocation.Longitude"] = false;
+		s["Vehicle.CurrentLocation.Heading"] = false;
+		s["Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Latitude"] = false;
+		s["Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Longitude"] = false;
+		s["Vehicle.Cabin.Infotainment.Navigation.ElapsedDistance"] = false;
+	} else {
+		// Router acts as actuator for these signals
+		// This is a bit convoluted, but would allow wiring up external destination
+		// setting with e.g. Alexa as has been done in the past.
+		s["Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Latitude"] = true;
+		s["Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Longitude"] = true;
+	}
+	m_vs->subscribe(s);
 }
 
 void Navigation::onSignalNotification(QString path, QString value, QString timestamp)
 {
-	// NOTE: Since all the known AGL users of the VSS signals are users of
-	//       this API, we know that updates occur in certain sequences and
-	//       can leverage this to roll up for emitting the existing events.
-	//       This is the path of least effort with respect to changing
-	//       the existing clients, but it may make sense down the road to
-	//       either switch them to using VehicleSignals directly or having
-	//       a more granular signal scheme that maps more directly onto
-	//       VSS.
 	if (path == "Vehicle.Cabin.Infotainment.Navigation.State") {
 		QVariantMap event;
 		event["state"] = value;
 		emit statusEvent(event);
 	} else if (path == "Vehicle.CurrentLocation.Latitude") {
+		m_position_mutex.lock();
 		m_latitude = value.toDouble();
+		m_latitude_set = true;
+		handlePositionUpdate();
+		m_position_mutex.unlock();
 	} else if (path == "Vehicle.CurrentLocation.Longitude") {
+		m_position_mutex.lock();
 		m_longitude = value.toDouble();
+		m_longitude_set = true;
+		handlePositionUpdate();
+		m_position_mutex.unlock();
 	} else if (path == "Vehicle.CurrentLocation.Heading") {
+		m_position_mutex.lock();
 		m_heading = value.toDouble();
+		m_heading_set = true;
+		handlePositionUpdate();
+		m_position_mutex.unlock();
 	} else if (path == "Vehicle.Cabin.Infotainment.Navigation.ElapsedDistance") {
+		m_position_mutex.lock();
 		m_distance = value.toDouble();
+		m_distance_set = true;
+		handlePositionUpdate();
+		m_position_mutex.unlock();
+	} else if (path == "Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Latitude") {
+		m_position_mutex.lock();
+		m_dest_latitude = value.toDouble();
+		m_dest_latitude_set = true;
+		handlePositionUpdate();
+		m_position_mutex.unlock();
+	} else if (path == "Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Longitude") {
+		m_position_mutex.lock();
+		m_dest_longitude = value.toDouble();
+		m_dest_longitude_set = true;
+		handlePositionUpdate();
+		m_position_mutex.unlock();
+
+		// NOTE: Potentially could emit a waypointsEvent here, but
+		//       nothing in the demo currently requires it, so do
+		//       not bother for now.  If something like Alexa is
+		//       added it or some other replacement / rework will
+		//       be required.
+	}
+}
+
+void Navigation::onSignalNotificationRouter(QString path, QString value, QString timestamp)
+{
+	if (path == "Vehicle.Cabin.Infotainment.Navigation.State") {
+		QVariantMap event;
+		event["state"] = value;
+		emit statusEvent(event);
+	} else if (path == "Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Latitude") {
+		m_vs->set(path, value.toDouble());
+	} else if (path == "Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Longitude") {
+		m_vs->set(path, value.toDouble());
+	}
+}
+
+// Private
+
+void Navigation::handlePositionUpdate()
+{
+	// NOTE: Since all the known AGL users of the VSS signals are users of
+	//       this API, we know that updates occur in certain sequences and
+	//       can leverage this to roll up for emitting the existing events.
+	//
+	//       The switch to the gRPC API for KUKSA.val complicates this as
+	//       we now have to live with the combination of only getting
+	//       notified when a signal changes to a new value on top of
+	//       notifications not necessarily happening in order by the time
+	//       they get through gRPC client/server/client/Qt stacks.  The "set"
+	//       flags give us something that mostly works for now, but further
+	//       investigation is required.  It is possible that either a switch
+	//       to a custom gRPC API (i.e. standalone nav service daemon) or
+	//       pushing for a rolled up position signal in a struct in upstream
+	//       VSS might be needed to do this better.
+
+	if (m_latitude_set && m_longitude_set && m_heading_set && m_distance_set) {
 		QVariantMap event;
 		event["position"] = "car";
 		event["latitude"] = m_latitude;
@@ -156,10 +209,9 @@ void Navigation::onSignalNotification(QString path, QString value, QString times
 		event["direction"] = m_heading;
 		event["distance"] = m_distance * 1000;
 		emit positionEvent(event);
-	} else if (path == "Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Latitude") {
-		m_dest_latitude = value.toDouble();
-	} else if (path == "Vehicle.Cabin.Infotainment.Navigation.DestinationSet.Longitude") {
-		m_dest_longitude = value.toDouble();
+		// The distance being updated is our trigger, so clear its flag.
+		m_distance_set = false;
+	} else if (m_latitude_set && m_longitude_set && m_dest_latitude_set && m_dest_longitude_set) {
 		QVariantMap event;
 		event["position"] = "route";
 		event["latitude"] = m_latitude;
@@ -167,11 +219,7 @@ void Navigation::onSignalNotification(QString path, QString value, QString times
 		event["route_latitude"] = m_dest_latitude;
 		event["route_longitude"] = m_dest_longitude;
 		emit positionEvent(event);
-
-		// NOTE: Potentially could emit a waypointsEvent here, but
-		//       nothing in the demo currently requires it, so do
-		//       not bother for now.  If something like Alexa is
-		//       added it or some other replacement / rework will
-		//       be required.
+		// The destination values are the triggers, so clear their flags.
+		m_dest_latitude_set = m_dest_longitude_set = false;
 	}
 }
diff --git a/navigation/navigation.h b/navigation/navigation.h
index 2c8a8ff..eb15ed3 100644
--- a/navigation/navigation.h
+++ b/navigation/navigation.h
@@ -1,17 +1,7 @@
  /*
- * Copyright (C) 2019-2022 Konsulko Group
+ * Copyright (C) 2019-2023 Konsulko Group
  *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * SPDX-License-Identifier: Apache-2.0
  */
 
 #ifndef NAVIGATION_H
@@ -19,6 +9,7 @@
 
 #include <QObject>
 #include <QVariant>
+#include <QMutex>
 
 class VehicleSignals;
 
@@ -27,7 +18,7 @@ class Navigation : public QObject
 	Q_OBJECT
 
 public:
-	explicit Navigation(VehicleSignals *vs, QObject *parent = Q_NULLPTR);
+	explicit Navigation(VehicleSignals *vs, bool router = false, QObject *parent = Q_NULLPTR);
 	virtual ~Navigation();
 
 	Q_INVOKABLE void broadcastPosition(double lat, double lon, double drc, double dst);
@@ -44,19 +35,29 @@ signals:
 
 private slots:
 	void onConnected();
-	void onAuthorized();
-	void onDisconnected();
 	void onSignalNotification(QString path, QString value, QString timestamp);
+	void onSignalNotificationRouter(QString path, QString value, QString timestamp);
 
 private:
+	void handlePositionUpdate();
+
 	VehicleSignals *m_vs;
-	bool m_connected;
+	bool m_router = false;
+	bool m_connected = false;
+
+	QMutex m_position_mutex;
 	double m_latitude;
+	bool m_latitude_set = false;
 	double m_longitude;
+	bool m_longitude_set = false;
 	double m_heading;
-	double m_distance;
+	bool m_heading_set = false;
+	double m_distance = 0.0;
+	bool m_distance_set = false;
 	double m_dest_latitude;
+	bool m_dest_latitude_set = false;
 	double m_dest_longitude;
+	bool m_dest_longitude_set = false;
 };
 
 #endif // NAVIGATION_H
diff --git a/vehicle-signals/QtKuksaClient.cpp b/vehicle-signals/QtKuksaClient.cpp
new file mode 100644
index 0000000..901459d
--- /dev/null
+++ b/vehicle-signals/QtKuksaClient.cpp
@@ -0,0 +1,421 @@
+/*
+ * Copyright (C) 2023 Konsulko Group
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <QDebug>
+#include <QSettings>
+#include <QUrl>
+#include <QFile>
+#include <QtConcurrent>
+#include <mutex>
+#include <chrono>
+
+#include "QtKuksaClient.h"
+
+using grpc::Channel;
+using grpc::ClientContext;
+using grpc::ClientReader;
+using grpc::Status;
+
+class QtKuksaClient::SubscribeReader : public grpc::ClientReadReactor<SubscribeResponse> {
+public:
+	SubscribeReader(VAL::Stub *stub,
+			QtKuksaClient *client,
+			VehicleSignalsConfig &config,
+			const QMap<QString, bool> &s,
+			const SubscribeRequest *request):
+		client_(client),
+		config_(config),
+		signals_(s) {
+		QString token = config_.authToken();
+		if (!token.isEmpty()) {
+			token.prepend("Bearer ");
+			context_.AddMetadata(std::string("authorization"), token.toStdString());
+		}
+		stub->async()->Subscribe(&context_, request, this);
+		StartRead(&response_);
+		StartCall();
+	}
+	void OnReadDone(bool ok) override {
+		std::unique_lock<std::mutex> lock(mutex_);
+		if (ok) {
+			if (client_)
+				client_->handleSubscribeResponse(&response_);
+			StartRead(&response_);
+		}
+	}
+	void OnDone(const Status& s) override {
+		status_ = s;
+		if (client_) {
+			if (config_.verbose() > 1)
+				qDebug() << "QtKuksaClient::subscribe::Reader done";
+			client_->handleSubscribeDone(signals_, status_);
+		}
+
+		// gRPC engine is done with us, safe to self-delete
+		delete this;
+	}
+
+private:
+	QtKuksaClient *client_;
+	VehicleSignalsConfig config_;
+	QMap<QString, bool> signals_;
+
+	ClientContext context_;
+	SubscribeResponse response_;
+	std::mutex mutex_;
+	Status status_;
+};
+
+QtKuksaClient::QtKuksaClient(const std::shared_ptr< ::grpc::ChannelInterface>& channel,
+			     const VehicleSignalsConfig &config,
+			     QObject *parent) :
+	QObject(parent),
+	m_channel(channel),
+	m_config(config),
+	m_connected(false)
+{
+        m_stub = VAL::NewStub(channel);
+
+}
+
+void QtKuksaClient::connect()
+{
+	// Check for connection in another thread
+	QFuture<void> future = QtConcurrent::run(this, &QtKuksaClient::waitForConnected);
+}
+
+void QtKuksaClient::get(const QString &path, const bool actuator)
+{
+	m_connected_mutex.lock();
+	if (!m_connected) {
+		m_connected_mutex.unlock();
+		return;
+	}
+	m_connected_mutex.unlock();
+	
+	ClientContext *context = new ClientContext();
+	if (!context) {
+		handleCriticalFailure("Could not create ClientContext");
+		return;
+	}
+	QString token = m_config.authToken();
+	if (!token.isEmpty()) {
+		token.prepend("Bearer ");
+		context->AddMetadata(std::string("authorization"), token.toStdString());
+	}
+
+	GetRequest request;
+	auto entry = request.add_entries();
+	entry->set_path(path.toStdString());
+	entry->add_fields(Field::FIELD_PATH);	
+	if (actuator)
+		entry->add_fields(Field::FIELD_ACTUATOR_TARGET);
+	else
+		entry->add_fields(Field::FIELD_VALUE);
+
+	GetResponse *response = new GetResponse();
+	if (!response) {
+		handleCriticalFailure("Could not create GetResponse");
+		return;
+	}
+
+	// NOTE: Using ClientUnaryReactor instead of the shortcut method
+	//       would allow getting detailed errors.
+	m_stub->async()->Get(context, &request, response,
+			     [this, context, response](Status s) {
+				     if (s.ok())
+					     handleGetResponse(response);
+				     delete response;
+				     delete context;
+			     });
+}
+
+// Since a set request needs a Datapoint with the appropriate type value,
+// checking the signal metadata to get the type would be a requirement for
+// a generic set call that takes a string as argument.  For now, assume
+// that set with a string is specifically for a signal of string type.
+
+void QtKuksaClient::set(const QString &path, const QString &value, const bool actuator)
+{
+	Datapoint dp;
+	dp.set_string(value.toStdString());
+	set(path, dp, actuator);
+}
+
+void QtKuksaClient::set(const QString &path, const qint32 value, const bool actuator)
+{
+	Datapoint dp;
+	dp.set_int32(value);
+	set(path, dp, actuator);
+}
+
+void QtKuksaClient::set(const QString &path, const qint64 value, const bool actuator)
+{
+	Datapoint dp;
+	dp.set_int64(value);
+	set(path, dp, actuator);
+}
+
+void QtKuksaClient::set(const QString &path, const quint32 value, const bool actuator)
+{
+	Datapoint dp;
+	dp.set_uint32(value);
+	set(path, dp, actuator);
+}
+
+void QtKuksaClient::set(const QString &path, const quint64 value, const bool actuator)
+{
+	Datapoint dp;
+	dp.set_uint64(value);
+	set(path, dp, actuator);
+}
+
+void QtKuksaClient::set(const QString &path, const float value, const bool actuator)
+{
+	Datapoint dp;
+	dp.set_float_(value);
+	set(path, dp, actuator);
+}
+
+void QtKuksaClient::set(const QString &path, const double value, const bool actuator)
+{
+	Datapoint dp;
+	dp.set_double_(value);
+	set(path, dp, actuator);
+}
+
+void QtKuksaClient::subscribe(const QString &path, const bool actuator)
+{
+	m_connected_mutex.lock();
+	if (!m_connected) {
+		m_connected_mutex.unlock();
+		return;
+	}
+	m_connected_mutex.unlock();
+
+	QMap<QString, bool> s;
+	s[path] = actuator;
+	subscribe(s);
+}
+
+void QtKuksaClient::subscribe(const QMap<QString, bool> &signals_)
+{
+	m_connected_mutex.lock();
+	if (!m_connected) {
+		m_connected_mutex.unlock();
+		return;
+	}
+	m_connected_mutex.unlock();
+
+	SubscribeRequest *request = new SubscribeRequest();
+	if (!request) {
+		handleCriticalFailure("Could not create SubscribeRequest");
+		return;
+	}
+
+	auto it = signals_.constBegin();
+	while (it != signals_.constEnd()) {
+		if (m_config.verbose() > 1)
+			qDebug() << "QtKuksaClient::subscribe: adding " << it.key() << ", actuator " << it.value();
+		auto entry = request->add_entries();
+		entry->set_path(it.key().toStdString());
+		entry->add_fields(Field::FIELD_PATH);	
+		if (it.value())
+			entry->add_fields(Field::FIELD_ACTUATOR_TARGET);
+		else
+			entry->add_fields(Field::FIELD_VALUE);
+		++it;
+	}
+
+	SubscribeReader *reader = new SubscribeReader(m_stub.get(), this, m_config, signals_, request);
+	if (!reader)
+		handleCriticalFailure("Could not create SubscribeReader");
+
+	delete request;
+}
+
+// Private
+
+void QtKuksaClient::waitForConnected()
+{
+	while (!m_channel->WaitForConnected(std::chrono::system_clock::now() +
+					  std::chrono::milliseconds(500)));
+
+	m_connected_mutex.lock();
+	m_connected = true;
+	m_connected_mutex.unlock();
+
+	qInfo() << "Databroker gRPC channel ready";
+	emit connected();
+}
+
+void QtKuksaClient::set(const QString &path, const Datapoint &dp, const bool actuator)
+{
+	m_connected_mutex.lock();
+	if (!m_connected) {
+		m_connected_mutex.unlock();
+		return;
+	}
+	m_connected_mutex.unlock();
+
+	ClientContext *context = new ClientContext();
+	if (!context) {
+		handleCriticalFailure("Could not create ClientContext");
+		return;
+	}
+	QString token = m_config.authToken();
+	if (!token.isEmpty()) {
+		token.prepend("Bearer ");
+		context->AddMetadata(std::string("authorization"), token.toStdString());
+	}
+
+	SetRequest request;
+	auto update = request.add_updates();
+	auto entry = update->mutable_entry();
+	entry->set_path(path.toStdString());
+	if (actuator) {
+		auto target = entry->mutable_actuator_target();
+		*target = dp;
+		update->add_fields(Field::FIELD_ACTUATOR_TARGET);
+	} else {
+		auto value = entry->mutable_value();
+		*value = dp;
+		update->add_fields(Field::FIELD_VALUE);		
+	}
+
+	SetResponse *response = new SetResponse();
+	if (!response) {
+		handleCriticalFailure("Could not create SetResponse");
+		delete context;
+		return;
+	}
+
+	// NOTE: Using ClientUnaryReactor instead of the shortcut method
+	//       would allow getting detailed errors.
+	m_stub->async()->Set(context, &request, response,
+				       [this, context, response](Status s) {
+					       if (s.ok())
+						       handleSetResponse(response);
+					       delete response;
+					       delete context;
+				       });
+}
+
+void QtKuksaClient::handleGetResponse(const GetResponse *response)
+{
+	if (!(response && response->entries_size()))
+		return;
+
+	for (auto it = response->entries().begin(); it != response->entries().end(); ++it) {
+		// We expect paths in the response entries
+		if (!it->path().size())
+			continue;
+		Datapoint dp;
+		if (it->has_actuator_target())
+			dp = it->actuator_target();
+		else
+			dp = it->value();
+
+		QString path = QString::fromStdString(it->path());
+		QString value;
+		QString timestamp;		
+		if (convertDatapoint(dp, value, timestamp)) {
+			if (m_config.verbose() > 1)
+				qDebug() << "QtKuksaClient::handleGetResponse: path = " << path << ", value = " << value;
+
+			emit getResponse(path, value, timestamp);
+		}
+	}
+}
+
+void QtKuksaClient::handleSetResponse(const SetResponse *response)
+{
+	if (!(response && response->errors_size()))
+		return;
+
+	for (auto it = response->errors().begin(); it != response->errors().end(); ++it) {
+		QString path = QString::fromStdString(it->path());
+		QString error = QString::fromStdString(it->error().reason());
+		emit setResponse(path, error);
+	}
+
+}
+
+void QtKuksaClient::handleSubscribeResponse(const SubscribeResponse *response)
+{
+	if (!(response && response->updates_size()))
+		return;
+
+	for (auto it = response->updates().begin(); it != response->updates().end(); ++it) {
+		// We expect entries that have paths in the response
+		if (!(it->has_entry() && it->entry().path().size()))
+			continue;
+
+		auto entry = it->entry();
+		QString path = QString::fromStdString(entry.path());
+
+		Datapoint dp;
+		if (entry.has_actuator_target())
+			dp = entry.actuator_target();
+		else
+			dp = entry.value();
+
+		QString value;
+		QString timestamp;		
+		if (convertDatapoint(dp, value, timestamp)) {
+			if (m_config.verbose() > 1)
+				qDebug() << "QtKuksaClient::handleSubscribeResponse: path = " << path << ", value = " << value;
+	
+			emit subscribeResponse(path, value, timestamp);
+		}
+	}
+}
+
+void QtKuksaClient::handleSubscribeDone(const QMap<QString, bool> &signals_, const Status &status)
+{
+	qInfo() << "QtKuksaClient::handleSubscribeDone: enter";
+	if (m_config.verbose() > 1)
+		qDebug() << "Subscribe status = " << status.error_code() <<
+			" (" << QString::fromStdString(status.error_message()) << ")";
+
+	emit subscribeDone(signals_, status.error_code() == grpc::CANCELLED);
+}
+
+bool QtKuksaClient::convertDatapoint(const Datapoint &dp, QString &value, QString &timestamp)
+{
+	// NOTE: Currently no array type support
+
+	if (dp.has_string())
+		value = QString::fromStdString(dp.string());
+	else if (dp.has_int32())
+		value = QString::number(dp.int32());
+	else if (dp.has_int64())
+		value = QString::number(dp.int64());
+	else if (dp.has_uint32())
+		value = QString::number(dp.uint32());
+	else if (dp.has_uint64())
+		value = QString::number(dp.uint64());
+	else if (dp.has_float_())
+		value = QString::number(dp.float_(), 'f', 6);
+	else if (dp.has_double_())
+		value = QString::number(dp.double_(), 'f', 6);
+	else if (dp.has_bool_())
+		value = dp.bool_() ? "true" : "false";
+	else {
+		if (m_config.verbose())
+			qWarning() << "Malformed response (unsupported value type)";
+		return false;
+	}
+
+	timestamp = QString::number(dp.timestamp().seconds()) + "." + QString::number(dp.timestamp().nanos());
+	return true;
+}
+
+void QtKuksaClient::handleCriticalFailure(const QString &error)
+{
+	if (error.size())
+		qCritical() << error;
+}
diff --git a/vehicle-signals/QtKuksaClient.h b/vehicle-signals/QtKuksaClient.h
new file mode 100644
index 0000000..1f24e09
--- /dev/null
+++ b/vehicle-signals/QtKuksaClient.h
@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2023 Konsulko Group
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef QT_KUKSA_CLIENT_H
+#define QT_KUKSA_CLIENT_H
+
+#include <QObject>
+#include <QMap>
+#include <QMutex>
+#include <grpcpp/grpcpp.h>
+#include "kuksa/val/v1/val.grpc.pb.h"
+
+// Just pull in the whole namespace since Datapoint contains a lot of
+// definitions that may potentially be needed.
+using namespace kuksa::val::v1;
+
+using grpc::Status;
+
+#include "VehicleSignalsConfig.h"
+
+// KUKSA.val databroker gRPC API Qt client class
+
+class QtKuksaClient : public QObject
+{
+	Q_OBJECT
+
+public:
+	explicit QtKuksaClient(const std::shared_ptr< ::grpc::ChannelInterface>& channel,
+			       const VehicleSignalsConfig &config,
+			       QObject * parent = Q_NULLPTR);
+
+	Q_INVOKABLE void connect();
+
+	Q_INVOKABLE void get(const QString &path, const bool actuator = false);
+
+	Q_INVOKABLE void set(const QString &path, const QString &value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const qint32 value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const qint64 value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const quint32 value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const quint64 value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const float value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const double value, const bool actuator = false);
+  
+	Q_INVOKABLE void subscribe(const QString &path, const bool actuator = false);
+	Q_INVOKABLE void subscribe(const QMap<QString, bool> &signals_);
+
+signals:
+	void connected();
+	void getResponse(QString path, QString value, QString timestamp);
+        void setResponse(QString path, QString error);
+        void subscribeResponse(QString path, QString value, QString timestamp);
+        void subscribeDone(const QMap<QString, bool> &signals_, bool canceled);
+
+private:
+	class SubscribeReader;
+
+	std::shared_ptr< ::grpc::ChannelInterface> m_channel;
+	VehicleSignalsConfig m_config;
+	std::shared_ptr<VAL::Stub> m_stub;
+	bool m_connected;
+	QMutex m_connected_mutex;
+
+	void waitForConnected();
+
+	void set(const QString &path, const Datapoint &dp, const bool actuator);
+
+	void handleGetResponse(const GetResponse *response);
+
+	void handleSetResponse(const SetResponse *response);
+
+	void handleSubscribeResponse(const SubscribeResponse *response);
+
+	void handleSubscribeDone(const QMap<QString, bool> &signals_, const Status &status);
+
+	void handleCriticalFailure(const QString &error);
+	void handleCriticalFailure(const char *error) { handleCriticalFailure(QString(error)); };
+
+	void resubscribe(const QMap<QString, bool> &signals_);
+
+	bool convertDatapoint(const Datapoint &dp, QString &value, QString &timestamp);
+};
+
+#endif // QT_KUKSA_CLIENT_H
diff --git a/vehicle-signals/VehicleSignalsConfig.cpp b/vehicle-signals/VehicleSignalsConfig.cpp
new file mode 100644
index 0000000..c72c2cd
--- /dev/null
+++ b/vehicle-signals/VehicleSignalsConfig.cpp
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2023 Konsulko Group
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <QDebug>
+#include <QSettings>
+#include <QUrl>
+#include <QFile>
+// ?
+//#include <QSslKey>
+//#include <QTimer>
+
+#include "VehicleSignalsConfig.h"
+
+#define DEFAULT_CLIENT_KEY_FILE  "/etc/kuksa-val/Client.key"
+#define DEFAULT_CLIENT_CERT_FILE "/etc/kuksa-val/Client.pem"
+#define DEFAULT_CA_CERT_FILE     "/etc/kuksa-val/CA.pem"
+
+VehicleSignalsConfig::VehicleSignalsConfig(const QString &hostname,
+					   const unsigned port,
+					   const QByteArray &caCert,
+					   const QString &tlsServerName,
+					   const QString &authToken) :
+	m_hostname(hostname),
+	m_port(port),
+	m_caCert(caCert),
+	m_tlsServerName(tlsServerName),
+	m_authToken(authToken),
+	m_verbose(0),
+	m_valid(true)
+{
+	// Potentially could do some certificate validation here...
+}
+
+VehicleSignalsConfig::VehicleSignalsConfig(const QString &appname)
+{
+	m_valid = false;
+
+	QSettings *pSettings = new QSettings("AGL", appname);
+	if (!pSettings)
+		return;
+
+	m_hostname = pSettings->value("kuksa-client/server", "localhost").toString();
+	if (m_hostname.isEmpty()) {
+		qCritical() << "Invalid server hostname";
+		return;
+	}
+
+	m_port = pSettings->value("kuksa-client/port", 55555).toInt();
+	if (m_port == 0) {
+		qCritical() << "Invalid server port";
+		return;
+	}
+
+	QString caCertFileName = pSettings->value("kuksa-client/ca-certificate", DEFAULT_CA_CERT_FILE).toString();
+	if (caCertFileName.isEmpty()) {
+		qCritical() << "Invalid CA certificate filename";
+		return;
+	}
+	QFile caCertFile(caCertFileName);
+	if (!caCertFile.open(QIODevice::ReadOnly)) {
+		qCritical() << "Could not open CA certificate file";
+		return;
+	}
+	QByteArray caCertData = caCertFile.readAll();
+	if (caCertData.isEmpty()) {
+		qCritical() << "Invalid CA certificate file";
+		return;
+	}
+	m_caCert = caCertData;
+
+	m_tlsServerName = pSettings->value("kuksa-client/tls-server-name", "").toString();
+
+	QString authTokenFileName = pSettings->value("kuksa-client/authorization").toString();
+	if (authTokenFileName.isEmpty()) {
+		qCritical() << "Invalid authorization token filename";
+		return;
+	}
+	QFile authTokenFile(authTokenFileName);
+	if (!authTokenFile.open(QIODevice::ReadOnly | QIODevice::Text)) {
+		qCritical() << "Could not open authorization token file";
+		return;
+	}
+	QTextStream in(&authTokenFile);
+	QString authToken = in.readLine();
+	if (authToken.isEmpty()) {
+		qCritical() << "Invalid authorization token file";
+		return;
+	}
+	m_authToken = authToken;
+
+	m_verbose = 0;
+	QString verbose = pSettings->value("kuksa-client/verbose").toString();
+	if (!verbose.isEmpty()) {
+		if (verbose == "true" || verbose == "1")
+			m_verbose = 1;
+		if (verbose == "2")
+			m_verbose = 2;
+	}
+
+	m_valid = true;
+}
diff --git a/vehicle-signals/VehicleSignalsConfig.h b/vehicle-signals/VehicleSignalsConfig.h
new file mode 100644
index 0000000..c3d52ca
--- /dev/null
+++ b/vehicle-signals/VehicleSignalsConfig.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2023 Konsulko Group
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef VEHICLE_SIGNALS_CONFIG_H
+#define VEHICLE_SIGNALS_CONFIG_H
+
+#include <QObject>
+
+// Class to read/hold VSS server configuration
+
+class VehicleSignalsConfig
+{
+public:
+        explicit VehicleSignalsConfig(const QString &hostname,
+				      const unsigned port,
+				      const QByteArray &caCert,
+				      const QString &tlsServerName,
+				      const QString &authToken);
+        explicit VehicleSignalsConfig(const QString &appname);
+        ~VehicleSignalsConfig() {};
+
+	QString hostname() { return m_hostname; };
+	unsigned port() { return m_port; };
+	QByteArray caCert() { return m_caCert; };
+	QString tlsServerName() { return m_tlsServerName; };
+	QString authToken() { return m_authToken; };
+	bool valid() { return m_valid; };
+	unsigned verbose() { return m_verbose; };
+
+private:
+	QString m_hostname;
+	unsigned m_port;
+	QByteArray m_caCert;
+	QString m_tlsServerName;
+	QString m_authToken;
+	bool m_valid = true;
+	unsigned m_verbose = 0;
+};
+
+#endif // VEHICLE_SIGNALS_CONFIG_H
diff --git a/vehicle-signals/meson.build b/vehicle-signals/meson.build
index e4c6dc0..50383e4 100644
--- a/vehicle-signals/meson.build
+++ b/vehicle-signals/meson.build
@@ -1,25 +1,69 @@
-qt5_dep = dependency('qt5', modules: ['Core', 'WebSockets'])
+cpp = meson.get_compiler('cpp')
+grpcpp_reflection_dep = cpp.find_library('grpc++_reflection')
 
-moc_files = qt5.compile_moc(headers: 'vehiclesignals.h',
+qt5_dep = dependency('qt5', modules: ['Core', 'Concurrent'])
+
+vs_dep = [
+    qt5_dep,
+    dependency('protobuf'),
+    dependency('grpc'),
+    dependency('grpc++'),
+    grpcpp_reflection_dep,
+]
+
+protoc = find_program('protoc')
+grpc_cpp = find_program('grpc_cpp_plugin')
+
+protos_base_dir = get_option('protos')
+protos_dir = protos_base_dir / 'kuksa/val/v1'
+protoc_gen = generator(protoc, \
+                       output : ['@BASENAME@.pb.cc', '@BASENAME@.pb.h'],
+                       arguments : ['-I=' + protos_base_dir,
+                         '--cpp_out=@BUILD_DIR@',
+                         '@INPUT@'])
+generated_protoc_sources = [ \
+    protoc_gen.process(protos_dir / 'types.proto', preserve_path_from : protos_base_dir),
+    protoc_gen.process(protos_dir / 'val.proto', preserve_path_from : protos_base_dir),
+]
+
+grpc_gen = generator(protoc, \
+                     output : ['@BASENAME@.grpc.pb.cc', '@BASENAME@.grpc.pb.h'],
+                     arguments : ['-I=' + protos_base_dir,
+                       '--grpc_out=@BUILD_DIR@',
+                       '--plugin=protoc-gen-grpc=' + grpc_cpp.path(),
+                       '@INPUT@'])
+generated_grpc_sources = [ \
+    grpc_gen.process(protos_dir / 'val.proto', preserve_path_from : protos_base_dir),
+]
+
+moc_files = qt5.compile_moc(headers: [ 'vehiclesignals.h', 'QtKuksaClient.h' ],
                             dependencies: qt5_dep)
 
-src = ['vehiclesignals.cpp', moc_files]
+src = [
+    'vehiclesignals.cpp',
+    'VehicleSignalsConfig.cpp',
+    'QtKuksaClient.cpp',
+    moc_files,
+    generated_protoc_sources,
+    generated_grpc_sources,
+]
+
 lib = shared_library('qtappfw-vehicle-signals',
                      sources: src,
                      version: '1.0.0',
                      soversion: '0',
-                     dependencies: qt5_dep,
+                     dependencies: vs_dep,
                      install: true)
 
-install_headers('vehiclesignals.h')
+install_headers(['vehiclesignals.h', 'VehicleSignalsConfig.h'])
 
 pkg_mod = import('pkgconfig')
 pkg_mod.generate(libraries: lib,
                  version: '1.0',
                  name: 'libqtappfw-vehicle-signals',
                  filebase: 'qtappfw-vehicle-signals',
-                 requires: ['Qt5Core', 'Qt5WebSockets'],
-                 description: 'Library wrapping VIS vehicle signaling API in Qt objects')
+                 requires: ['Qt5Core'],
+                 description: 'Library wrapping VSS API in Qt objects')
 
 qtappfw_vs_dep = declare_dependency(dependencies: qt5_dep,
                                     link_with: lib,
diff --git a/vehicle-signals/vehiclesignals.cpp b/vehicle-signals/vehiclesignals.cpp
index d6cf8eb..adf371a 100644
--- a/vehicle-signals/vehiclesignals.cpp
+++ b/vehicle-signals/vehiclesignals.cpp
@@ -1,427 +1,176 @@
 /*
- * Copyright (C) 2022 Konsulko Group
+ * Copyright (C) 2022,2023 Konsulko Group
  *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * SPDX-License-Identifier: Apache-2.0
  */
 
 #include <QDebug>
-#include <QSettings>
-#include <QUrl>
-#include <QFile>
-#include <QSslKey>
-#include <QTimer>
-#include <QVariantMap>
-#include <QJsonDocument>
-#include <QJsonObject>
+#include <QtConcurrent>
 
 #include "vehiclesignals.h"
+#include "QtKuksaClient.h"
 
-#define DEFAULT_CLIENT_KEY_FILE  "/etc/kuksa-val/Client.key"
-#define DEFAULT_CLIENT_CERT_FILE "/etc/kuksa-val/Client.pem"
-#define DEFAULT_CA_CERT_FILE     "/etc/kuksa-val/CA.pem"
-
-VehicleSignalsConfig::VehicleSignalsConfig(const QString &hostname,
-					   const unsigned port,
-					   const QByteArray &clientKey,
-					   const QByteArray &clientCert,
-					   const QByteArray &caCert,
-					   const QString &authToken,
-					   bool verifyPeer) :
-	m_hostname(hostname),
-	m_port(port),
-	m_clientKey(clientKey),
-	m_clientCert(clientCert),
-	m_caCert(caCert),
-	m_authToken(authToken),
-	m_verifyPeer(verifyPeer),
-	m_verbose(0),
-	m_valid(true)
-{
-	// Potentially could do some certificate validation here...
-}
-
-VehicleSignalsConfig::VehicleSignalsConfig(const QString &appname)
+VehicleSignals::VehicleSignals(const VehicleSignalsConfig &config, QObject *parent) :
+	QObject(parent),
+	m_config(config)
 {
-	m_valid = false;
-
-	QSettings *pSettings = new QSettings("AGL", appname);
-	if (!pSettings)
-		return;
-
-	m_hostname = pSettings->value("vis-client/server", "localhost").toString();
-	if (m_hostname.isEmpty()) {
-		qCritical() << "Invalid server hostname";
-		return;
-	}
-
-	m_port = pSettings->value("vis-client/port", 8090).toInt();
-	if (m_port == 0) {
-		qCritical() << "Invalid server port";
-		return;
-	}
-
-	// Default to disabling peer verification for now to be able
-        // to use the default upstream KUKSA.val certificates for
-	// testing.  Wrangling server and CA certificate generation
-	// and management to be able to verify will require further
-	// investigation.
-	m_verifyPeer = pSettings->value("vis-client/verify-server", false).toBool();
-
-	QString keyFileName = pSettings->value("vis-client/key", DEFAULT_CLIENT_KEY_FILE).toString();
-	if (keyFileName.isEmpty()) {
-		qCritical() << "Invalid client key filename";
-		return;
-	}
-	QFile keyFile(keyFileName);
-	if (!keyFile.open(QIODevice::ReadOnly)) {
-		qCritical() << "Could not open client key file";
-		return;
-	}
-	QByteArray keyData = keyFile.readAll();
-	if (keyData.isEmpty()) {
-		qCritical() << "Invalid client key file";
-		return;
-	}
-	m_clientKey = keyData;
-
-	QString certFileName = pSettings->value("vis-client/certificate", DEFAULT_CLIENT_CERT_FILE).toString();
-	if (certFileName.isEmpty()) {
-		qCritical() << "Invalid client certificate filename";
-		return;
-	}
-	QFile certFile(certFileName);
-	if (!certFile.open(QIODevice::ReadOnly)) {
-		qCritical() << "Could not open client certificate file";
-		return;
-	}
-	QByteArray certData = certFile.readAll();
-	if (certData.isEmpty()) {
-		qCritical() << "Invalid client certificate file";
-		return;
-	}
-	m_clientCert = certData;
-
-	QString caCertFileName = pSettings->value("vis-client/ca-certificate", DEFAULT_CA_CERT_FILE).toString();
-	if (caCertFileName.isEmpty()) {
-		qCritical() << "Invalid CA certificate filename";
-		return;
-	}
-	QFile caCertFile(caCertFileName);
-	if (!caCertFile.open(QIODevice::ReadOnly)) {
-		qCritical() << "Could not open CA certificate file";
-		return;
-	}
-	QByteArray caCertData = caCertFile.readAll();
-	if (caCertData.isEmpty()) {
-		qCritical() << "Invalid CA certificate file";
-		return;
-	}
-	// Pre-check CA certificate
-	QList<QSslCertificate> newSslCaCerts = QSslCertificate::fromData(caCertData);
-	if (newSslCaCerts.isEmpty()) {
-		qCritical() << "Invalid CA certificate";
-		return;
-	}
-	m_caCert = caCertData;
-
-	QString authTokenFileName = pSettings->value("vis-client/authorization").toString();
-	if (authTokenFileName.isEmpty()) {
-		qCritical() << "Invalid authorization token filename";
-		return;
-	}
-	QFile authTokenFile(authTokenFileName);
-	if (!authTokenFile.open(QIODevice::ReadOnly | QIODevice::Text)) {
-		qCritical() << "Could not open authorization token file";
-		return;
-	}
-	QTextStream in(&authTokenFile);
-	QString authToken = in.readLine();
-	if (authToken.isEmpty()) {
-		qCritical() << "Invalid authorization token file";
-		return;
+	// Create gRPC channel
+	// NOTE: channel creation and waiting for connected state could be put into
+	//       a thread that is spawned here.
+
+  	QString host = m_config.hostname();
+	host += ":";
+	host += QString::number(m_config.port());
+
+	std::shared_ptr<grpc::Channel> channel;
+	if (!m_config.caCert().isEmpty()) {
+		qInfo() << "Using TLS";
+		grpc::SslCredentialsOptions options;
+		options.pem_root_certs = m_config.caCert().toStdString();
+		if (!m_config.tlsServerName().isEmpty()) {
+			grpc::ChannelArguments args;
+			auto target = m_config.tlsServerName();
+			qInfo() << "Overriding TLS target name with " << target;
+			args.SetString(GRPC_SSL_TARGET_NAME_OVERRIDE_ARG, target.toStdString());
+			channel = grpc::CreateCustomChannel(host.toStdString(), grpc::SslCredentials(options), args);
+		} else {
+			channel = grpc::CreateChannel(host.toStdString(), grpc::SslCredentials(options));
+		}
+	} else {
+		channel = grpc::CreateChannel(host.toStdString(), grpc::InsecureChannelCredentials());
 	}
-	m_authToken = authToken;
 
-	m_verbose = 0;
-	QString verbose = pSettings->value("vis-client/verbose").toString();
-	if (!verbose.isEmpty()) {
-		if (verbose == "true" || verbose == "1")
-			m_verbose = 1;
-		if (verbose == "2")
-			m_verbose = 2;
-	}
+	m_broker = new QtKuksaClient(channel, config);
+	if (!m_broker)
+		qCritical() << "gRPC client initialization failed";
 
-	m_valid = true;
-}
-
-VehicleSignals::VehicleSignals(const VehicleSignalsConfig &config, QObject *parent) :
-	QObject(parent),
-	m_config(config),
-	m_request_id(0)
-{
-	QObject::connect(&m_websocket, &QWebSocket::connected, this, &VehicleSignals::onConnected);
-	QObject::connect(&m_websocket, QOverload<QAbstractSocket::SocketError>::of(&QWebSocket::error),
-			 this, &VehicleSignals::onError);
-	QObject::connect(&m_websocket, &QWebSocket::disconnected, this, &VehicleSignals::onDisconnected);
+	QObject::connect(m_broker, &QtKuksaClient::connected, this, &VehicleSignals::onConnected);
 }
 
 VehicleSignals::~VehicleSignals()
 {
-	m_websocket.close();
+	delete m_broker;
 }
 
 void VehicleSignals::connect()
 {
-	if (!m_config.valid()) {
-		qCritical() << "Invalid VIS server configuration";
-		return;
-	}
-
-	QUrl visUrl;
-	visUrl.setScheme(QStringLiteral("wss"));
-	visUrl.setHost(m_config.hostname());
-	visUrl.setPort(m_config.port());
-
-	QSslConfiguration sslConfig = QSslConfiguration::defaultConfiguration();
-
-	// Add client private key
-        // i.e. kuksa_certificates/Client.key in source tree
-	QSslKey sslKey(m_config.clientKey(), QSsl::Rsa);
-	sslConfig.setPrivateKey(sslKey);
-
-	// Add local client certificate
-        // i.e. kuksa_certificates/Client.pem in source tree
-	QList<QSslCertificate> sslCerts = QSslCertificate::fromData(m_config.clientCert());
-	if (sslCerts.empty()) {
-		qCritical() << "Invalid client certificate";
-		return; 
-	}
-	sslConfig.setLocalCertificate(sslCerts.first());
-
-	// Add CA certificate
-        // i.e. kuksa_certificates/CA.pem in source tree
-	// Note the following can be simplified with QSslConfiguration::addCaCertificate with Qt 5.15
-	QList<QSslCertificate> sslCaCerts = sslConfig.caCertificates();
-	QList<QSslCertificate> newSslCaCerts = QSslCertificate::fromData(m_config.caCert());
-	if (newSslCaCerts.empty()) {
-		qCritical() << "Invalid CA certificate";
-		return;
-	}
-	sslCaCerts.append(newSslCaCerts.first());
-	sslConfig.setCaCertificates(sslCaCerts);
-
-	sslConfig.setPeerVerifyMode(m_config.verifyPeer() ? QSslSocket::VerifyPeer : QSslSocket::VerifyNone);
+	// QtKuksaClient will call our onConnected slot when the channel
+	// is connected, and then we pass that along via our connected
+	// signal.
+	if (m_broker)
+		m_broker->connect();
+}
 
-	m_websocket.setSslConfiguration(sslConfig);
+void VehicleSignals::authorize()
+{
+	// Databroker has no separate authorize call, so this is a no-op
+	emit authorized();
+}
 
-	if (m_config.verbose())
-		qInfo() << "Opening VIS websocket";
-	m_websocket.open(visUrl);
+void VehicleSignals::get(const QString &path, const bool actuator)
+{
+	if (m_broker)
+		m_broker->get(path, actuator);
 }
 
-void VehicleSignals::onConnected()
+void VehicleSignals::set(const QString &path, const QString &value, const bool actuator)
 {
-	if (m_config.verbose() > 1)
-		qDebug() << "VehicleSignals::onConnected: enter";
-	QObject::connect(&m_websocket, &QWebSocket::textMessageReceived, this, &VehicleSignals::onTextMessageReceived);
-	emit connected();
+	if (m_broker)
+		m_broker->set(path, value, actuator);
 }
 
-void VehicleSignals::onError(QAbstractSocket::SocketError error)
+void VehicleSignals::set(const QString &path, const qint32 value, const bool actuator)
 {
-	if (m_config.verbose() > 1)
-		qDebug() << "VehicleSignals::onError: enter";
-	QTimer::singleShot(1000, this, &VehicleSignals::reconnect);
+	if (m_broker)
+		m_broker->set(path, value, actuator);
 }
 
-void VehicleSignals::reconnect()
+void VehicleSignals::set(const QString &path, const qint64 value, const bool actuator)
 {
-	if (m_config.verbose() > 1)
-		qDebug() << "VehicleSignals::reconnect: enter";
-	connect();
+	if (m_broker)
+		m_broker->set(path, value, actuator);
 }
 
-void VehicleSignals::onDisconnected()
+void VehicleSignals::set(const QString &path, const quint32 value, const bool actuator)
 {
-	if (m_config.verbose() > 1)
-		qDebug() << "VehicleSignals::onDisconnected: enter";
-	QObject::disconnect(&m_websocket, &QWebSocket::textMessageReceived, this, &VehicleSignals::onTextMessageReceived);
-	emit disconnected();
+	if (m_broker)
+		m_broker->set(path, value, actuator);
+}
 
-	// Try to reconnect
-	QTimer::singleShot(1000, this, &VehicleSignals::reconnect);
+void VehicleSignals::set(const QString &path, const quint64 value, const bool actuator)
+{
+	if (m_broker)
+		m_broker->set(path, value, actuator);
 }
 
-void VehicleSignals::authorize()
+void VehicleSignals::set(const QString &path, const float value, const bool actuator)
 {
-	QVariantMap map;
-	map["action"] = QString("authorize");
-	map["tokens"] = m_config.authToken();
-	map["requestId"] = QString::number(m_request_id++);
-	QJsonDocument doc = QJsonDocument::fromVariant(map);
-	m_websocket.sendTextMessage(doc.toJson(QJsonDocument::Compact).data());
+	if (m_broker)
+		m_broker->set(path, value, actuator);
 }
 
-void VehicleSignals::get(const QString &path)
+void VehicleSignals::set(const QString &path, const double value, const bool actuator)
 {
-	QVariantMap map;
-	map["action"] = QString("get");
-	map["tokens"] = m_config.authToken();
-	map["path"] = path;
-	map["requestId"] = QString::number(m_request_id++);
-	QJsonDocument doc = QJsonDocument::fromVariant(map);
-	m_websocket.sendTextMessage(doc.toJson(QJsonDocument::Compact).data());
+	if (m_broker)
+		m_broker->set(path, value, actuator);
 }
 
-void VehicleSignals::set(const QString &path, const QString &value)
+void VehicleSignals::subscribe(const QString &path, bool actuator)
 {
-	QVariantMap map;
-	map["action"] = QString("set");
-	map["tokens"] = m_config.authToken();
-	map["path"] = path;
-	map["value"] = value;
-	map["requestId"] = QString::number(m_request_id++);
-	QJsonDocument doc = QJsonDocument::fromVariant(map);
-	m_websocket.sendTextMessage(doc.toJson(QJsonDocument::Compact).data());
+	if (m_broker)
+		m_broker->subscribe(path, actuator);
 }
 
-void VehicleSignals::subscribe(const QString &path)
+void VehicleSignals::subscribe(const QMap<QString, bool> &signals_)
 {
-	QVariantMap map;
-	map["action"] = QString("subscribe");
-	map["tokens"] = m_config.authToken();
-	map["path"] = path;
-	map["requestId"] = QString::number(m_request_id++);
-	QJsonDocument doc = QJsonDocument::fromVariant(map);
-	m_websocket.sendTextMessage(doc.toJson(QJsonDocument::Compact).data());
+	if (m_broker)
+		m_broker->subscribe(signals_);
 }
 
-bool VehicleSignals::parseData(const QJsonObject &response, QString &path, QString &value, QString &timestamp)
+// Slots
+
+void VehicleSignals::onConnected()
 {
-	if (response.contains("error")) {
-		QString error = response.value("error").toString();
-		return false;
-	}
+	QObject::connect(m_broker, &QtKuksaClient::getResponse, this, &VehicleSignals::onGetResponse);
+	QObject::connect(m_broker, &QtKuksaClient::setResponse, this, &VehicleSignals::onSetResponse);
+	QObject::connect(m_broker, &QtKuksaClient::subscribeResponse, this, &VehicleSignals::onSubscribeResponse);
+	//QObject::connect(m_broker, &QtKuksaClient::subscribeDone, this, &VehicleSignals::onSubscribeDone);
 
-	if (!(response.contains("data") && response["data"].isObject())) {
-		qWarning() << "Malformed response (data missing)";
-		return false;
-	}
-	QJsonObject data = response["data"].toObject();
-	if (!(data.contains("path") && data["path"].isString())) {
-		qWarning() << "Malformed response (path missing)";
-		return false;
-	}
-	path = data["path"].toString();
-	// Convert '/' to '.' in paths to ensure consistency for clients
-	path.replace(QString("/"), QString("."));
+	emit connected();
+}
 
-	if (!(data.contains("dp") && data["dp"].isObject())) {
-		qWarning() << "Malformed response (datapoint missing)";
-		return false;
-	}
-	QJsonObject dp = data["dp"].toObject();
-	if (!dp.contains("value")) {
-		qWarning() << "Malformed response (value missing)";
-		return false;
-	} else if (dp["value"].isString()) {
-		value = dp["value"].toString();
-	} else if (dp["value"].isDouble()) {
-		value = QString::number(dp["value"].toDouble(), 'f', 9);
-	} else if (dp["value"].isBool()) {
-		value = dp["value"].toBool() ? "true" : "false";
-	} else {
-		qWarning() << "Malformed response (unsupported value type)";
-		return false;
-	}
+void VehicleSignals::onGetResponse(QString path, QString value, QString timestamp)
+{
+	emit getSuccessResponse(path, value, timestamp);
+}
 
-	if (!(dp.contains("ts") && dp["ts"].isString())) {
-		qWarning() << "Malformed response (timestamp missing)";
-		return false;
-	}
-	timestamp = dp["ts"].toString();
+void VehicleSignals::onSetResponse(QString path, QString error)
+{
+	emit setErrorResponse(path, error);
+}
 
-	return true;
+void VehicleSignals::onSubscribeResponse(QString path, QString value, QString timestamp)
+{
+	if (m_config.verbose() > 1)
+		qDebug() << "VehicleSignals::onSubscribeResponse: got " << path << " = " << value;
+	emit signalNotification(path, value, timestamp);
 }
 
-//
-// NOTE:
-//
-// Ideally request ids would be used to provide some form of mapping
-// to callers of get/set for responses/errors.  At present the demo
-// usecases are simple enough that it does not seem worth implementing
-// just yet.
-//
-void VehicleSignals::onTextMessageReceived(QString msg)
+void VehicleSignals::onSubscribeDone(const QMap<QString, bool> &signals_, bool canceled)
 {
-	msg = msg.simplified();
-	QJsonDocument doc(QJsonDocument::fromJson(msg.toUtf8()));
-	if (doc.isEmpty()) {
-		qWarning() << "Received invalid JSON: empty VIS message";
-		return;
+	if (!canceled) {
+		// queue up a resubscribe attempt
+		QFuture<void> future = QtConcurrent::run(this, &VehicleSignals::resubscribe, signals_);
 	}
+}
 
-	if (!doc.isObject()) {
-		qWarning() << "Received invalid JSON: malformed VIS message";
-		return;
-	}
-	QJsonObject obj = doc.object();
+// Private
 
-	if (!obj.contains("action")) {
-		qWarning() << "Received unknown message (no action), discarding";
-		return;
-	}
-	
-	QString action = obj.value("action").toString();
-	if (action == "authorize") {
-		if (obj.contains("error")) {
-			QString error = obj.value("error").toString();
-			qWarning() << "VIS authorization failed: " << error;
-		} else {
-			if (m_config.verbose() > 1)
-				qDebug() << "authorized";
-			emit authorized();
-		}
-	} else if (action == "subscribe") {
-		if (obj.contains("error")) {
-			QString error = obj.value("error").toString();
-			qWarning() << "VIS subscription failed: " << error;
-		}
-	} else if (action == "get") {
-		if (obj.contains("error")) {
-			QString error = obj.value("error").toString();
-			qWarning() << "VIS get failed: " << error;
-		} else {
-			QString path, value, ts;
-			if (parseData(obj, path, value, ts)) {
-				if (m_config.verbose() > 1)
-					qDebug() << "VehicleSignals::onTextMessageReceived: emitting response" << path << " = " << value;
-				emit getSuccessResponse(path, value, ts);
-			}
-		}
-	} else if (action == "set") {
-		if (obj.contains("error")) {
-			QString error = obj.value("error").toString();
-			qWarning() << "VIS set failed: " << error;
-		}
-	} else if (action == "subscription") {
-		QString path, value, ts;
-		if (parseData(obj, path, value, ts)) {
-			if (m_config.verbose() > 1)
-				qDebug() << "VehicleSignals::onTextMessageReceived: emitting notification" << path << " = " << value;
-			emit signalNotification(path, value, ts);
-		}
-	} else {
-		qWarning() << "unhandled VIS response of type: " << action;
-	}
+void VehicleSignals::resubscribe(const QMap<QString, bool> &signals_)
+{
+	// Delay 100 milliseconds between subscribe attempts
+	QThread::msleep(100);
+
+	if (m_broker)
+		m_broker->subscribe(signals_);
 }
diff --git a/vehicle-signals/vehiclesignals.h b/vehicle-signals/vehiclesignals.h
index fd5fe9c..734cb27 100644
--- a/vehicle-signals/vehiclesignals.h
+++ b/vehicle-signals/vehiclesignals.h
@@ -1,63 +1,19 @@
 /*
- * Copyright (C) 2022 Konsulko Group
+ * Copyright (C) 2022,2023 Konsulko Group
  *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * SPDX-License-Identifier: Apache-2.0
  */
 
 #ifndef VEHICLESIGNALS_H
 #define VEHICLESIGNALS_H
 
 #include <QObject>
-#include <QWebSocket>
 
-// Class to read/hold VIS server configuration
+#include "VehicleSignalsConfig.h"
 
-class VehicleSignalsConfig
-{
-public:
-        explicit VehicleSignalsConfig(const QString &hostname,
-				      const unsigned port,
-				      const QByteArray &clientKey,
-				      const QByteArray &clientCert,
-				      const QByteArray &caCert,
-				      const QString &authToken,
-				      bool verifyPeer = true);
-        explicit VehicleSignalsConfig(const QString &appname);
-        ~VehicleSignalsConfig() {};
-
-	QString hostname() { return m_hostname; };
-	unsigned port() { return m_port; };
-	QByteArray clientKey() { return m_clientKey; };
-	QByteArray clientCert() { return m_clientCert; };
-	QByteArray caCert() { return m_caCert; };
-	QString authToken() { return m_authToken; };
-	bool verifyPeer() { return m_verifyPeer; };
-	bool valid() { return m_valid; };
-	unsigned verbose() { return m_verbose; };
+class QtKuksaClient;
 
-private:
-	QString m_hostname;
-	unsigned m_port;
-	QByteArray m_clientKey;
-	QByteArray m_clientCert;
-	QByteArray m_caCert;
-	QString m_authToken;
-	bool m_verifyPeer;
-	bool m_valid;
-	unsigned m_verbose;
-};
-
-// VIS signaling interface class
+// VSS signal interface class
 
 class VehicleSignals : public QObject
 {
@@ -70,30 +26,39 @@ public:
 	Q_INVOKABLE void connect();	
 	Q_INVOKABLE void authorize();
 
-	Q_INVOKABLE void get(const QString &path);
-	Q_INVOKABLE void set(const QString &path, const QString &value);
-	Q_INVOKABLE void subscribe(const QString &path);
+	Q_INVOKABLE void get(const QString &path, const bool actuator = false);
+
+	Q_INVOKABLE void set(const QString &path, const QString &value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const qint32 value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const qint64 value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const quint32 value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const quint64 value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const float value, const bool actuator = false);
+	Q_INVOKABLE void set(const QString &path, const double value, const bool actuator = false);
+
+	Q_INVOKABLE void subscribe(const QString &path, const bool actuator = false);
+	Q_INVOKABLE void subscribe(const QMap<QString, bool> &signals_);
 
 signals:
 	void connected();
 	void authorized();
-        void getSuccessResponse(QString path, QString value, QString timestamp);
-        void signalNotification(QString path, QString value, QString timestamp);
 	void disconnected();
+	void getSuccessResponse(QString path, QString value, QString timestamp);
+	void setErrorResponse(QString path, QString error);
+	void signalNotification(QString path, QString value, QString timestamp);
 
 private slots:
 	void onConnected();
-	void onError(QAbstractSocket::SocketError error);
-	void reconnect();
-	void onDisconnected();
-	void onTextMessageReceived(QString message);
+	void onGetResponse(QString path, QString value, QString timestamp);
+	void onSetResponse(QString path, QString error);
+	void onSubscribeResponse(QString path, QString value, QString timestamp);
+	void onSubscribeDone(const QMap<QString, bool> &signals_, bool canceled);
 
 private:
 	VehicleSignalsConfig m_config;
-	QWebSocket m_websocket;
-	std::atomic<unsigned int> m_request_id;
+	QtKuksaClient *m_broker;
 
-	bool parseData(const QJsonObject &response, QString &path, QString &value, QString &timestamp);
+	void resubscribe(const QMap<QString, bool> &signals_);
 };
 
 #endif // VEHICLESIGNALS_H