Add VIS vehicle signal support

Add vehicle-signals library that exposes configuration and interface
objects to use Vehicle Information Service (VIS) signals from a VIS
server such as KUKSA.val.  In this initial version Qt signals to
expose some of the low level VIS errors to clients have not been
implemented, as it is not immediately obvious how they could be
leveraged in the AGL demo usecases.  If the Qt demos continue to be
used for past the Needlefish release this may warrant revisiting.

Bug-AGL: SPEC-4408

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: I05d2bfdd09d090e3ed13ba4e4c2d1d205357d6e4
(cherry picked from commit b34fae267102d374bcc9ab7a6ff6a259515bb6bf)

1 files changed, 427 insertions, 0 deletions

diff --git a/vehicle-signals/vehiclesignals.cpp b/vehicle-signals/vehiclesignals.cpp
new file mode 100644
index 0000000..f3db521
--- /dev/null
+++ b/vehicle-signals/vehiclesignals.cpp
@@ -0,0 +1,427 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+
+#include <QDebug>
+#include <QSettings>
+#include <QUrl>
+#include <QFile>
+#include <QSslKey>
+#include <QTimer>
+#include <QVariantMap>
+#include <QJsonDocument>
+#include <QJsonObject>
+
+#include "vehiclesignals.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)
+{
+	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;
+	}
+	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_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);
+}
+
+VehicleSignals::~VehicleSignals()
+{
+	m_websocket.close();
+}
+
+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);
+
+	m_websocket.setSslConfiguration(sslConfig);
+
+	if (m_config.verbose())
+		qInfo() << "Opening VIS websocket";
+	m_websocket.open(visUrl);
+}
+
+void VehicleSignals::onConnected()
+{
+	if (m_config.verbose() > 1)
+		qDebug() << "VehicleSignals::onConnected: enter";
+	QObject::connect(&m_websocket, &QWebSocket::textMessageReceived, this, &VehicleSignals::onTextMessageReceived);
+	emit connected();
+}
+
+void VehicleSignals::onError(QAbstractSocket::SocketError error)
+{
+	if (m_config.verbose() > 1)
+		qDebug() << "VehicleSignals::onError: enter";
+	QTimer::singleShot(1000, this, &VehicleSignals::reconnect);
+}
+
+void VehicleSignals::reconnect()
+{
+	if (m_config.verbose() > 1)
+		qDebug() << "VehicleSignals::reconnect: enter";
+	connect();
+}
+
+void VehicleSignals::onDisconnected()
+{
+	if (m_config.verbose() > 1)
+		qDebug() << "VehicleSignals::onDisconnected: enter";
+	QObject::disconnect(&m_websocket, &QWebSocket::textMessageReceived, this, &VehicleSignals::onTextMessageReceived);
+	emit disconnected();
+
+	// Try to reconnect
+	QTimer::singleShot(1000, this, &VehicleSignals::reconnect);
+}
+
+void VehicleSignals::authorize()
+{
+	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());
+}
+
+void VehicleSignals::get(const QString &path)
+{
+	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());
+}
+
+void VehicleSignals::set(const QString &path, const QString &value)
+{
+	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());
+}
+
+void VehicleSignals::subscribe(const QString &path)
+{
+	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());
+}
+
+bool VehicleSignals::parseData(const QJsonObject &response, QString &path, QString &value, QString &timestamp)
+{
+	if (response.contains("error")) {
+		QString error = response.value("error").toString();
+		return false;
+	}
+
+	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("."));
+
+	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.setNum(dp["value"].toDouble());
+	} else if (dp["value"].isBool()) {
+		value = dp["value"].toBool() ? "true" : "false";
+	} else {
+		qWarning() << "Malformed response (unsupported value type)";
+		return false;
+	}
+
+	if (!(dp.contains("ts") && dp["ts"].isString())) {
+		qWarning() << "Malformed response (timestamp missing)";
+		return false;
+	}
+	timestamp = dp["ts"].toString();
+
+	return true;
+}
+
+//
+// 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)
+{
+	msg = msg.simplified();
+	QJsonDocument doc(QJsonDocument::fromJson(msg.toUtf8()));
+	if (doc.isEmpty()) {
+		qWarning() << "Received invalid JSON: empty VIS message";
+		return;
+	}
+
+	if (!doc.isObject()) {
+		qWarning() << "Received invalid JSON: malformed VIS message";
+		return;
+	}
+	QJsonObject obj = doc.object();
+
+	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;
+	}
+}