make protoconnection to invalid host less blocking

Former-commit-id: e7a89c87b15fbe9809ec63468b59ecc55c6d3e72

include/protoserver/ProtoConnection.h

@@ -7,6 +7,7 @@
 #include <QColor>
 #include <QImage>
 #include <QTcpSocket>
+#include <QTimer>
 #include <QMap>
 
 // hyperion util
@@ -19,8 +20,11 @@
 ///
 /// Connection class to setup an connection to the hyperion server and execute commands
 ///
-class ProtoConnection
+class ProtoConnection : public QObject
 {
+
+Q_OBJECT
+
 public:
     ///
     /// Constructor
@@ -74,10 +78,13 @@ public:
     ///
     void sendMessage(const proto::HyperionRequest & message);
 
-private:
+private slots:
     /// Try to connect to the Hyperion host
     void connectToHost();
 
+
+private:
+
     ///
     /// Parse a reply message
     ///
@@ -99,4 +106,7 @@ private:
 
     /// Skip receiving reply messages from Hyperion if set
     bool _skipReply;
+
+    QTimer _timer;
+    QAbstractSocket::SocketState  _prevSocketState;
 };

libsrc/protoserver/ProtoConnection.cpp

@@ -9,7 +9,8 @@
 
 ProtoConnection::ProtoConnection(const std::string & a) :
     _socket(),
-    _skipReply(false)
+    _skipReply(false),
+    _prevSocketState(QAbstractSocket::UnconnectedState)
 {
     QString address(a.c_str());
     QStringList parts = address.split(":");
@@ -29,10 +30,18 @@ ProtoConnection::ProtoConnection(const std::string & a) :
     // try to connect to host
     std::cout << "Connecting to Hyperion: " << _host.toStdString() << ":" << _port << std::endl;
     connectToHost();
+
+    // start the connection timer
+    _timer.setInterval(5000);
+    _timer.setSingleShot(false);
+
+    connect(&_timer,SIGNAL(timeout()), this, SLOT(connectToHost()) );
+    _timer.start();
 }
 
 ProtoConnection::~ProtoConnection()
 {
+    _timer.stop();
     _socket.close();
 }
 
@@ -91,20 +100,37 @@ void ProtoConnection::clearAll()
 
 void ProtoConnection::connectToHost()
 {
-    _socket.connectToHost(_host, _port);
-    if (_socket.waitForConnected()) {
-        std::cout << "Connected to Hyperion host" << std::endl;
+    // try connection only when 
+    if (_socket.state() == QAbstractSocket::UnconnectedState)
+    {
+       _socket.connectToHost(_host, _port);
+       //_socket.waitForConnected(1000);
     }
 }
 
 void ProtoConnection::sendMessage(const proto::HyperionRequest &message)
 {
-    if (_socket.state() == QAbstractSocket::UnconnectedState)
+    // print out connection message only when state is changed
+    if (_socket.state() != _prevSocketState )
     {
-        std::cout << "Currently disconnected: trying to connect to host" << std::endl;
-        connectToHost();
+      switch (_socket.state() )
+      {
+        case QAbstractSocket::UnconnectedState:
+          std::cout << "No connection to Hyperion: " << _host.toStdString() << ":" << _port << std::endl;
+          break;
+
+        case QAbstractSocket::ConnectedState:
+          std::cout << "Connected to Hyperion: " << _host.toStdString() << ":" << _port << std::endl;
+          break;
+
+        default:
+          //std::cout << "Connecting to Hyperion: " << _host.toStdString() << ":" << _port << std::endl;
+          break;
+      }
+      _prevSocketState = _socket.state();
     }
 
+
     if (_socket.state() != QAbstractSocket::ConnectedState)
     {
         return;