ground/gcs/src/plugins/streamservice/streamserviceplugin.cpp

   1 /**
   2  ******************************************************************************
   3  *
   4  * @file       streamserviceplugin.h
   5  * @author     The LibrePilot Project, http://www.librepilot.org Copyright (C) 2016.
   6  * @addtogroup GCSPlugins GCS Plugins
   7  * @{
   8  * @addtogroup StreamServicePlugin Plugin
   9  * @{
  10  * @brief Data UAV Data objects TCP/IP stream service
  11  *****************************************************************************/
  12 /*
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 3 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful, but
  19  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  20  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  21  * for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License along
  24  * with this program; if not, write to the Free Software Foundation, Inc.,
  25  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  26  */
  27 #include "streamserviceplugin.h"
  28
  29 #include <QJsonObject>
  30 #include <QJsonDocument>
  31 #include <QMessageBox>
  32 #include <QDateTime>
  33 #include <QTcpServer>
  34 #include <QTcpSocket>
  35
  36 #include "extensionsystem/pluginmanager.h"
  37 #include "../uavobjects/uavobjectmanager.h"
  38 #include "../uavobjects/uavdataobject.h"
  39
  40 StreamServicePlugin::StreamServicePlugin() :
  41     port(7891),
  42     isSubscribed(false) {}
  43
  44 StreamServicePlugin::~StreamServicePlugin()
  45 {
  46     if (pServer == Q_NULLPTR) {
  47         return;
  48     }
  49     if (pServer->isListening()) {
  50         foreach(QTcpSocket * client, activeClients) {
  51             /* Disconnect the client discarding pending
  52              * bytes */
  53             if (client->isOpen()) {
  54                 client->close();
  55             }
  56         }
  57         pServer->close();
  58     }
  59 }
  60
  61 bool StreamServicePlugin::initialize(const QStringList &arguments, QString *errorString)
  62 {
  63     Q_UNUSED(arguments);
  64     Q_UNUSED(errorString);
  65
  66     pServer = new QTcpServer();
  67
  68     if (!pServer->listen(QHostAddress::Any, port)) {
  69         *errorString = tr("Couldn't start StreamService: ") + pServer->errorString();
  70         return false;
  71     }
  72
  73     connect(pServer, &QTcpServer::newConnection, this, &StreamServicePlugin::clientConnected);
  74
  75     return true;
  76 }
  77
  78 void StreamServicePlugin::extensionsInitialized()
  79 {
  80     if (pServer == Q_NULLPTR) {
  81         return;
  82     }
  83
  84     pServer->resumeAccepting();
  85 }
  86
  87 void StreamServicePlugin::shutdown()
  88 {
  89     if (pServer != Q_NULLPTR) {
  90         pServer->pauseAccepting();
  91     }
  92
  93     foreach(QTcpSocket * pClient, activeClients) {
  94         pClient->disconnectFromHost();
  95     }
  96 }
  97
  98 void StreamServicePlugin::objectUpdated(UAVObject *pObj)
  99 {
 100     QJsonObject qtjson;
 101
 102     pObj->toJson(qtjson);
 103
 104     // Adds timestamp: Milliseconds from epoch
 105     qtjson.insert("gcs_timestamp_ms", QJsonValue(QDateTime::currentMSecsSinceEpoch()));
 106
 107     QJsonDocument jsonDoc(qtjson);
 108     QString strJson = QString(jsonDoc.toJson(QJsonDocument::Compact)) + "\n";
 109
 110     foreach(QTcpSocket * pClient, activeClients) {
 111         if (pClient->isOpen()) {
 112             if (pClient->write(strJson.toUtf8().constData(), strJson.length())) {
 113                 pClient->flush();
 114             }
 115         }
 116     }
 117 }
 118
 119 void StreamServicePlugin::clientConnected()
 120 {
 121     QTcpSocket *pending = pServer->nextPendingConnection();
 122
 123     if (pending == Q_NULLPTR) {
 124         return;
 125     }
 126     makeSureIsSubscribed();
 127
 128     connect(pending, &QTcpSocket::disconnected, this, &StreamServicePlugin::clientDisconnected);
 129     activeClients.append(pending);
 130 }
 131
 132 void StreamServicePlugin::clientDisconnected()
 133 {
 134     disconnect(sender());
 135     activeClients.removeAll((QTcpSocket *)sender());
 136 }
 137
 138 inline void StreamServicePlugin::makeSureIsSubscribed()
 139 {
 140     if (isSubscribed) {
 141         return;
 142     }
 143
 144     ExtensionSystem::PluginManager *pm = ExtensionSystem::PluginManager::instance();
 145     UAVObjectManager *objManager = pm->getObject<UAVObjectManager>();
 146     Q_ASSERT(objManager);
 147
 148     QList< QList<UAVDataObject *> > objList = objManager->getDataObjects();
 149     foreach(QList<UAVDataObject *> list, objList) {
 150         foreach(UAVDataObject * obj, list) {
 151             connect(obj, &UAVDataObject::objectUpdated, this, &StreamServicePlugin::objectUpdated);
 152         }
 153     }
 154     isSubscribed = true;
 155 }