Added some more examples

Implemented a C++ Server, providing a chatservice through a simple
QObject using QWebChannel and also both a QML and HTML Client to
interact with the server.
The examples show how to use properties, signals and methods,
separated in server and clients.

This reverts commit e8c280a15f7822fa5a563388615313858fd90848.
The integration issues w.r.t. unconditional usage of the
websockets module have been resolved.

Change-Id: I4a07646dcd5e6050d3bd6b9bd1c5b07dbc7d7d69
Reviewed-by: Milian Wolff <milian.wolff@kdab.com>

5 files changed, 364 insertions, 0 deletions

diff --git a/examples/webchannel/chatserver-cpp/chatserver-cpp.pro b/examples/webchannel/chatserver-cpp/chatserver-cpp.pro
new file mode 100644
index 0000000..ce6a3f7
--- /dev/null
+++ b/examples/webchannel/chatserver-cpp/chatserver-cpp.pro
@@ -0,0 +1,18 @@
+TARGET = chatserver
+
+TEMPLATE = app
+
+QT       += core websockets webchannel
+QT       -= gui
+
+CONFIG   += console
+
+SOURCES += main.cpp \
+    chatserver.cpp \
+    ../shared/websocketclientwrapper.cpp \
+    ../shared/websockettransport.cpp
+
+HEADERS += \
+    chatserver.h \
+    ../shared/websocketclientwrapper.h \
+    ../shared/websockettransport.h
diff --git a/examples/webchannel/chatserver-cpp/chatserver.cpp b/examples/webchannel/chatserver-cpp/chatserver.cpp
new file mode 100644
index 0000000..4663549
--- /dev/null
+++ b/examples/webchannel/chatserver-cpp/chatserver.cpp
@@ -0,0 +1,124 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Milian Wolff <milian.wolff@kdab.com>
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtWebChannel module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "chatserver.h"
+
+#include <QtCore/QDebug>
+#include <QTimer>
+#include <QTime>
+
+QT_BEGIN_NAMESPACE
+
+ChatServer::ChatServer(QObject *parent)
+    : QObject(parent)
+{
+    QTimer* t = new QTimer(this);
+    connect(t, SIGNAL(timeout()), this, SLOT(sendKeepAlive()));
+    t->start(10000);
+
+    m_keepAliveCheckTimer = new QTimer(this);
+    m_keepAliveCheckTimer->setSingleShot(true);
+    m_keepAliveCheckTimer->setInterval(2000);
+    connect(m_keepAliveCheckTimer, SIGNAL(timeout()), this, SLOT(checkKeepAliveResponses()));
+}
+
+ChatServer::~ChatServer()
+{}
+
+
+bool ChatServer::login(const QString& userName)
+{
+    //stop keepAliveCheck, when a new user logged in
+    if (m_keepAliveCheckTimer->isActive()) {
+        m_keepAliveCheckTimer->stop();
+        m_stillAliveUsers.clear();
+    }
+
+    if (m_userList.contains(userName)) {
+        return false;
+    }
+
+    qDebug() << "User logged in:" << userName;
+    m_userList.append(userName);
+    m_userList.sort();
+    emit userListChanged();
+    emit userCountChanged();
+    return true;
+}
+
+bool ChatServer::logout(const QString& userName)
+{
+    if (!m_userList.contains(userName)) {
+        return false;
+    } else {
+        m_userList.removeAt(m_userList.indexOf(userName));
+        emit userListChanged();
+        emit userCountChanged();
+        return true;
+    }
+}
+
+bool ChatServer::sendMessage(const QString& user, const QString& msg)
+{
+    if (m_userList.contains(user)) {
+        emit newMessage(QTime::currentTime().toString("HH:mm:ss"), user, msg);
+        return true;
+    } else {
+        return false;
+    }
+}
+
+void ChatServer::sendKeepAlive() {
+    emit keepAlive();
+    m_keepAliveCheckTimer->start();
+}
+
+void ChatServer::checkKeepAliveResponses() {
+    qDebug() << "Keep Alive Check" << m_stillAliveUsers;
+    m_userList = m_stillAliveUsers;
+    m_stillAliveUsers.clear();
+    m_userList.sort();
+    emit userListChanged();
+}
+
+void ChatServer::keepAliveResponse(const QString& user) {
+    m_stillAliveUsers.append(user);
+}
+
+
+QStringList ChatServer::userList() const
+{
+    return m_userList;
+}
+
+QT_END_NAMESPACE
diff --git a/examples/webchannel/chatserver-cpp/chatserver.h b/examples/webchannel/chatserver-cpp/chatserver.h
new file mode 100644
index 0000000..eba219a
--- /dev/null
+++ b/examples/webchannel/chatserver-cpp/chatserver.h
@@ -0,0 +1,88 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Milian Wolff <milian.wolff@kdab.com>
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtWebChannel module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef ChatServer_H
+#define ChatServer_H
+
+#include <QObject>
+#include <QStringList>
+
+QT_BEGIN_NAMESPACE
+
+class QTimer;
+
+class ChatServer : public QObject
+{
+    Q_OBJECT
+
+    Q_PROPERTY(QStringList userList READ userList NOTIFY userListChanged)
+
+public:
+    explicit ChatServer(QObject *parent = 0);
+    virtual ~ChatServer();
+
+public:
+    //a user logs in with the given username
+    Q_INVOKABLE bool login(const QString& userName);
+
+    //the user logs out, will be removed from userlist immediately
+    Q_INVOKABLE bool logout(const QString& userName);
+
+    //a user sends a message to all other users
+    Q_INVOKABLE bool sendMessage(const QString& user, const QString& msg);
+
+    //response of the keep alive signal from a client.
+    // This is used to detect disconnects.
+    Q_INVOKABLE void keepAliveResponse(const QString& user);
+
+    QStringList userList() const;
+
+protected slots:
+    void sendKeepAlive();
+    void checkKeepAliveResponses();
+
+signals:
+    void newMessage(QString time, QString user, QString msg);
+    void keepAlive();
+    void userListChanged();
+    void userCountChanged();
+
+private:
+    QStringList m_userList;
+    QStringList m_stillAliveUsers;
+    QTimer* m_keepAliveCheckTimer;
+};
+
+QT_END_NAMESPACE
+
+#endif // ChatServer_H
diff --git a/examples/webchannel/chatserver-cpp/doc/src/chatserver-cpp.qdoc b/examples/webchannel/chatserver-cpp/doc/src/chatserver-cpp.qdoc
new file mode 100644
index 0000000..ceae6ab
--- /dev/null
+++ b/examples/webchannel/chatserver-cpp/doc/src/chatserver-cpp.qdoc
@@ -0,0 +1,63 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 basysKom GmbH, author Bernd Lamecker <bernd.lamecker@basyskom.com>
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtWebChannel module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+    \example chatserver-cpp
+    \title Qt WebChannel Chatserver Example
+    \ingroup qtwebchannel-examples
+    \brief Shows how to use the QWebChannel C++ API to implement a simple chat server
+
+    The chatserver examples provides a chat service that client examples can connect to.
+
+    \section1 Overview
+
+    The C++ application implements a QObject which provides all mechanisms required for
+    a chat service.
+    This object is published through a QWebChannel which uses a WebSocket as transport.
+
+    The server provides a basic \c login method (username only, no passwords), which must be
+    successfully invoked before a client is able to chat.
+    After login a client can invoke the method \c sendMessage and receive the signal \c newMessage
+    to write and receive messages. Furthermore there is a \c userList property which provides
+    the names of all other connected clients.
+    Additionally the server sends a keepAlive signal periodically to all clients. The clients
+    have to respond to this signal, otherwise the client will be removed from the \c userList property.
+
+    The example shows how basic QObject elements can be used with QWebChannel, i.e. signals
+    (\c newMessage), slots (\c sendMessage) and properties (\c userList).
+
+    Because this is a plain server application, there are separated clients needed to interact
+    with the server. Both examples chatclient-qml and chatclient-html show a client implementation
+    compatible with this server.
+
+*/
diff --git a/examples/webchannel/chatserver-cpp/main.cpp b/examples/webchannel/chatserver-cpp/main.cpp
new file mode 100644
index 0000000..d971bee
--- /dev/null
+++ b/examples/webchannel/chatserver-cpp/main.cpp
@@ -0,0 +1,71 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Milian Wolff <milian.wolff@kdab.com>
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtWebChannel module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qwebchannel.h"
+
+#include <QCoreApplication>
+#include <QUrl>
+#include <QDebug>
+
+#include <QtWebSockets/QWebSocketServer>
+
+#include "../shared/websocketclientwrapper.h"
+#include "../shared/websockettransport.h"
+#include "chatserver.h"
+
+
+int main(int argc, char** argv)
+{
+    QCoreApplication app(argc, argv);
+
+    QWebSocketServer server(QStringLiteral("QWebChannel Standalone Example Server"),
+                            QWebSocketServer::NonSecureMode);
+    if (!server.listen(QHostAddress::LocalHost, 12345)) {
+        qFatal("Failed to open web socket server.");
+        return 1;
+    }
+
+    // wrap WebSocket clients in QWebChannelAbstractTransport objects
+    WebSocketClientWrapper clientWrapper(&server);
+
+    // setup the channel
+    QWebChannel channel;
+    QObject::connect(&clientWrapper, &WebSocketClientWrapper::clientConnected,
+                     &channel, &QWebChannel::connectTo);
+
+    // setup the dialog and publish it to the QWebChannel
+    ChatServer* chatserver = new ChatServer(&app);
+    channel.registerObject("chatserver", chatserver);
+
+    return app.exec();
+}