SensorTag: Prefer loading MQTT configuration from file

To avoid accidently pushing credentials, they should not be patched into
the header, but rather be placed in to a file co-located to the
executable.

Change-Id: I03950107f39a88b0f1c7deb49ff16d25ddf9df4d
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>

1 files changed, 65 insertions, 4 deletions

diff --git a/tradeshow/iot-sensortag/mqttdataproviderpool.cpp b/tradeshow/iot-sensortag/mqttdataproviderpool.cpp
index 24ce47c..55cd0f7 100644
--- a/tradeshow/iot-sensortag/mqttdataproviderpool.cpp
+++ b/tradeshow/iot-sensortag/mqttdataproviderpool.cpp
@@ -52,6 +52,8 @@
 #include "mqttdataprovider.h"
 
 #include <QtCore/QDebug>
+#include <QtCore/QFile>
+#include <QtCore/QJsonDocument>
 
 MqttDataProviderPool::MqttDataProviderPool(QObject *parent)
     : DataProviderPool(parent)
@@ -66,10 +68,10 @@ void MqttDataProviderPool::startScanning()
     emit providersUpdated();
     emit dataProvidersChanged();
 
-    m_client->setHostname(QLatin1String(MQTT_BROKER));
-    m_client->setPort(MQTT_PORT);
-    m_client->setUsername(QByteArray(MQTT_USERNAME));
-    m_client->setPassword(QByteArray(MQTT_PASSWORD));
+    m_client->setHostname(MqttCredentials::getBroker());
+    m_client->setPort((quint16)MqttCredentials::getPort());
+    m_client->setUsername(MqttCredentials::getUsername());
+    m_client->setPassword(MqttCredentials::getPassword());
 
     connect(m_client, &QMqttClient::connected, [this]() {
         auto sub = m_client->subscribe(QLatin1String("sensors/active"));
@@ -121,3 +123,62 @@ void MqttDataProviderPool::deviceUpdate(const QMqttMessage &msg)
         emit dataProvidersChanged();
     }
 }
+
+namespace {
+    static QString gBroker;
+    static int gPort{0};
+    static QString gUser;
+    static QString gPassword;
+    bool resolveCredentials() {
+        static bool resolved = false;
+        if (resolved)
+            return true;
+
+        QFile f(QLatin1String("broker.json"));
+        if (!f.open(QIODevice::ReadOnly)) {
+            qDebug() << "Could not find or open broker.json";
+            return false;
+        }
+        const QByteArray data = f.readAll();
+        if (data.isEmpty()) {
+            qDebug() << "broker.json file empty";
+            return false;
+        }
+        QJsonDocument doc = QJsonDocument::fromJson(data);
+        if (doc.isNull()) {
+            qDebug() << "broker.json does not contain valid data";
+            return false;
+        }
+        gBroker = doc["broker"].toString();
+        gPort = doc["port"].toInt();
+        gUser = doc["user"].toString();
+        gPassword = doc["password"].toString();
+        qDebug() << "broker.json parsed. Using broker:" << gBroker << ":" << gPort;
+        resolved = true;
+        return true;
+    }
+}
+
+QString MqttCredentials::getBroker()
+{
+    resolveCredentials();
+    return gBroker;
+}
+
+int MqttCredentials::getPort()
+{
+    resolveCredentials();
+    return gPort;
+}
+
+QString MqttCredentials::getUsername()
+{
+    resolveCredentials();
+    return gUser;
+}
+
+QString MqttCredentials::getPassword()
+{
+    resolveCredentials();
+    return gPassword;
+}