Faire du HTTP server PUSH avec QT en C++

Je continue avec ma série sur le server PUSH. En effet, j'ai du tester plusieurs solutions afin de trouver celle qui me convenait le mieux. En voici, donc une autre basé sur QT.

Voici d'abord l'implémentation du serveur:

Server.h

#ifndef ServerHttp_H #define ServerHttp_H #include <QTcpServer> #include <QTcpSocket> #include <QThread> #include <QTimer> class ServerHttp : public QTcpServer { Q_OBJECT public: ServerHttp(QObject *parent = 0); ~ServerHttp(); bool start(int port); private slots: void generateNextStep(); signals: void stepReady(int step); protected: void incomingConnection(int socketDescriptor); private: int m_step; QTimer m_timer; int m_port; }; class ServerThread : public QThread { Q_OBJECT public: ServerThread(int socketDescriptor, QObject *parent = 0); ~ServerThread(); void run(); signals: void error(QTcpSocket::SocketError socketError); public slots: void stepReady(int step); private: void writeHeaders(); int m_socketDescriptor; QTcpSocket * m_socket; }; #endif //ServerHttp_H

Server.cpp

#include "Server.h" ServerHttp::ServerHttp(QObject *parent) : QTcpServer(parent) { m_step = 0; m_timer.setInterval(1000); connect(&m_timer, SIGNAL(timeout()), this, SLOT(generateNextStep())); } ServerHttp::~ServerHttp() { } bool ServerHttp::start(int port) { if(!listen(QHostAddress::Any,port)) { qDebug() << "ServerHttp::start(): Unable to open Server Push on port"<<port<<": Is it already in use?"; return false; } qDebug() << "ServerHttp::start(): Started Server Push on port "<<port; return true; } void ServerHttp::incomingConnection(int socketDescriptor) { ServerThread *thread = new ServerThread(socketDescriptor); connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater())); connect(this, SIGNAL(stepReady(int)), thread, SLOT(stepReady(int)), Qt::QueuedConnection); thread->start(); qDebug() << "ServerHttp: Client Connected, Socket Descriptor:"<<socketDescriptor; thread->moveToThread(thread); if(!m_timer.isActive()) m_timer.start(); } void ServerHttp::generateNextStep() { emit stepReady(m_step); m_step++; } /** Thread **/ #define BOUNDARY "ServerThread-uuid-0eda9b03a8314df4840c97113e3fe160" ServerThread::ServerThread(int socketDescriptor, QObject *parent) : QThread(parent) , m_socketDescriptor(socketDescriptor) { } ServerThread::~ServerThread() { m_socket->abort(); delete m_socket; } void ServerThread::run() { m_socket = new QTcpSocket(); if (!m_socket->setSocketDescriptor(m_socketDescriptor)) { emit error(m_socket->error()); return; } writeHeaders(); // enter event loop exec(); // when stepReady() signal arrives, write data with header to socket } void ServerThread::writeHeaders() { m_socket->write("HTTP/1.0 200 OK\r\n"); m_socket->write("Content-Type: multipart/x-mixed-replace;boundary=" BOUNDARY "\r\n"); m_socket->write("\r\n"); m_socket->write("--" BOUNDARY "\r\n"); } void ServerThread::stepReady(int step) { static int frameCounter = 0; frameCounter++; qDebug() << "ServerThread::stepReady(): Sending text " << frameCounter << ", threadId:"<<QThread::currentThreadId(); if(m_socket->state() == QAbstractSocket::ConnectedState) { //m_socket->write("Content-type: image/jpeg\r\n\r\n"); m_socket->write("Content-type: text/plain\r\n\r\n"); QString szTmp; szTmp.sprintf("Step %d", step); m_socket->write(qPrintable(szTmp)); } m_socket->write("--" BOUNDARY "\r\n"); }


Puis voici le code permettant de démarrer le service.

main.cpp

#include <iostream> #include <QCoreApplication> #include <QtGlobal> #include "Server.h" #include <unistd.h> using namespace std; int main(int argc, char *argv[]) { qDebug("Starting server"); // Initialize the QT application QCoreApplication a(argc, argv); // Port qDebug("Starting service"); quint16 port = 8081; ServerHttp* server = new ServerHttp(&a); if (!server->start(port)) { qCritical("Failed to bind port: %d", port); } qDebug("Starting the main loop"); a.exec(); return 0; }

Enfin comme tout projet QT, voici le fichier du projet, nécessaire pour compiler le server.

TestServerQt.pro

TEMPLATE = app TARGET = DEPENDPATH += . INCLUDEPATH += . # Input HEADERS += Server.h SOURCES += main.cpp Server.cpp QT += network

Il ne vous reste alors plus qu'a lancer les commandes:

• qmake TestServerQt.pro
• make
• ./TestServerQt

On peut alors attaquer le serveur depuis le navigateur en pointant l'adresse : http://localhost:8081/