websocket_server.cpp

/*
 * Copyright (c) 2017-2018 dresden elektronik ingenieurtechnik gmbh.
 * All rights reserved.
 *
 * The software in this package is published under the terms of the BSD
 * style license a copy of which has been included with this distribution in
 * the LICENSE.txt file.
 *
 */

#ifdef USE_WEBSOCKETS

#include "deconz/dbg_trace.h"
#include "websocket_server.h"

/*! Constructor.
 */
WebSocketServer::WebSocketServer(QObject *parent, quint16 port) :
    QObject(parent)
{
    srv = new QWebSocketServer("deconz", QWebSocketServer::NonSecureMode, this);

    quint16 p = 0;
    quint16 ports[] = { 443, 443, 8080, 8088, 20877, 0 }; // start with proxy frinedly ports first, use random port as fallback
    if (port > 0)
    {
        ports[0] = port;
    }

    while (!srv->listen(QHostAddress::AnyIPv4, ports[p]))
    {
        if (ports[p] == 0)
        {
            DBG_Printf(DBG_ERROR, "giveup starting websocket server on port %u. error: %s\n", ports[p], qPrintable(srv->errorString()));
            break;
        }

        DBG_Printf(DBG_ERROR, "failed to start websocket server on port %u. error: %s\n", ports[p], qPrintable(srv->errorString()));
        p++;
    }

    if (srv->isListening())
    {
        DBG_Printf(DBG_INFO, "started websocket server at port %u\n", srv->serverPort());
        connect(srv, SIGNAL(newConnection()), this, SLOT(onNewConnection()));
    }
}

/*! Returns the websocket server port.
    \return the active server port, or 0 if not active
 */
quint16 WebSocketServer::port() const
{
    return srv->isListening() ? srv->serverPort() : 0;
}

/*! Handler for new client connections.
 */
void WebSocketServer::onNewConnection()
{
    while (srv->hasPendingConnections())
    {
        QWebSocket *sock = srv->nextPendingConnection();
        DBG_Printf(DBG_INFO, "New websocket %s:%u (state: %d) \n", qPrintable(sock->peerAddress().toString()), sock->peerPort(), sock->state());
        connect(sock, SIGNAL(disconnected()), this, SLOT(onSocketDisconnected()));
        connect(sock, SIGNAL(error(QAbstractSocket::SocketError)), this, SLOT(onSocketError(QAbstractSocket::SocketError)));
        clients.push_back(sock);
    }
}

/*! Handle websocket disconnected signal.
 */
void WebSocketServer::onSocketDisconnected()
{
    for (size_t i = 0; i < clients.size(); i++)
    {
        QWebSocket *sock = qobject_cast<QWebSocket*>(sender());
        DBG_Assert(sock);
        if (sock && clients[i] == sock)
        {
            DBG_Printf(DBG_INFO, "Websocket disconnected %s:%u (state: %d) \n", qPrintable(sock->peerAddress().toString()), sock->peerPort(), sock->state());
            sock->deleteLater();
            clients[i] = clients.back();
            clients.pop_back();
        }
    }
}

/*! Handle websocket error signal.
    \param err - the error which occured
 */
void WebSocketServer::onSocketError(QAbstractSocket::SocketError err)
{
    Q_UNUSED(err);
    for (size_t i = 0; i < clients.size(); i++)
    {
        QWebSocket *sock = qobject_cast<QWebSocket*>(sender());
        DBG_Assert(sock);
        if (sock && clients[i] == sock)
        {
            DBG_Printf(DBG_INFO, "Remove websocket %s:%u after error %s\n",
                       qPrintable(sock->peerAddress().toString()), sock->peerPort(), qPrintable(sock->errorString()));
            sock->deleteLater();
            clients[i] = clients.back();
            clients.pop_back();
        }
    }
}

/*! Broadcasts a message to all connected clients.
    \param msg the message as JSON string
 */
void WebSocketServer::broadcastTextMessage(const QString &msg)
{
    for (size_t i = 0; i < clients.size(); i++)
    {
        QWebSocket *sock = clients[i];

        if (sock->state() != QAbstractSocket::ConnectedState)
        {
            DBG_Printf(DBG_INFO, "Websocket %s:%u unexpected state: %d\n", qPrintable(sock->peerAddress().toString()), sock->peerPort(), sock->state());
        }

        qint64 ret = sock->sendTextMessage(msg);
        DBG_Printf(DBG_INFO_L2, "Websocket %s:%u send message: %s (ret = %d)\n", qPrintable(sock->peerAddress().toString()), sock->peerPort(), qPrintable(msg), ret);
        sock->flush();
    }
}

/*! Flush the sockets of all connected clients.
 */
void WebSocketServer::flush()
{
    for (size_t i = 0; i < clients.size(); i++)
    {
        QWebSocket *sock = clients[i];

        if (sock->state() == QAbstractSocket::ConnectedState)
        {
            sock->flush();
        }
    }
}

#else // no websockets
  WebSocketServer::WebSocketServer(QObject *parent) :
      QObject(parent)
  { }
  void WebSocketServer::onNewConnection() { }
  void WebSocketServer::broadcastTextMessage(const QString &) { }
  quint16 WebSocketServer::port() const {  return 0; }
#endif