Make the underlying transport mechanism of the webchannel pluggable.

This enables us to optionally use navigator.qt instead of a WebSocket,
which is nicer setup-wise and is also slightly faster:

navigator.qt:
284.0 msecs per iteration (total: 2,840, iterations: 10)
WebSocket:
295.8 msecs per iteration (total: 2,959, iterations: 10)

The baseline is ca. 203 msecs, which would mean a performance boost
of ca. 12.7%.

Furthermore, this sets the fundation to eventually add a WebEngine
transport mechanism. The WebViewTransport should also be removed and
instead the WebView itself should directly implement the
WebChannelTransportInterface.

Change-Id: I368bb27e38ffa2f17ffeb7f5ae695690f6f5ad21
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

19 files changed, 658 insertions, 109 deletions

diff --git a/src/imports/webchannel/plugin.cpp b/src/imports/webchannel/plugin.cpp
index 92aac79..589e3cb 100644
--- a/src/imports/webchannel/plugin.cpp
+++ b/src/imports/webchannel/plugin.cpp
@@ -43,6 +43,11 @@
 #include <QtQml/QQmlExtensionPlugin>
 
 #include "qmlwebchannel.h"
+#include "qwebsockettransport.h"
+#include "qmlwebviewtransport.h"
+#include "qwebchanneltransportinterface.h"
+
+QML_DECLARE_INTERFACE_HASMETATYPE(QWebChannelTransportInterface);
 
 QT_BEGIN_NAMESPACE
 
@@ -57,10 +62,13 @@ public:
 
 void QWebChannelPlugin::registerTypes(const char *uri)
 {
+    qmlRegisterInterface<QWebChannelTransportInterface>("QWebChannelTransportInterface");
+
     int major = 1;
     int minor = 0;
     qmlRegisterType<QmlWebChannel>(uri, major, minor, "WebChannel");
-
+    qmlRegisterType<QWebSocketTransport>(uri, major, minor, "WebSocketTransport");
+    qmlRegisterType<QmlWebViewTransport>(uri, major, minor, "WebViewTransport");
 }
 
 QT_END_NAMESPACE
diff --git a/src/imports/webchannel/qmlwebchannel.cpp b/src/imports/webchannel/qmlwebchannel.cpp
index 7c70f5c..dc7398d 100644
--- a/src/imports/webchannel/qmlwebchannel.cpp
+++ b/src/imports/webchannel/qmlwebchannel.cpp
@@ -51,7 +51,6 @@ QT_USE_NAMESPACE
 QmlWebChannel::QmlWebChannel(QObject *parent)
     : QWebChannel(parent)
 {
-
 }
 
 QmlWebChannel::~QmlWebChannel()
@@ -99,6 +98,37 @@ QmlWebChannelAttached *QmlWebChannel::qmlAttachedProperties(QObject *obj)
     return new QmlWebChannelAttached(obj);
 }
 
+void QmlWebChannel::connectTo(QObject *transport)
+{
+    if (QWebChannelTransportInterface *iface = qobject_cast<QWebChannelTransportInterface*>(transport)) {
+        m_connectedObjects.insert(transport, iface);
+        QWebChannel::connectTo(iface);
+        connect(transport, SIGNAL(destroyed(QObject*)), SLOT(transportDestroyed(QObject*)), Qt::UniqueConnection);
+    } else {
+        qWarning() << "Cannot connect to transport" << transport << " - it does not implement the QWebChannelTransportInterface.";
+    }
+}
+
+void QmlWebChannel::disconnectFrom(QObject *transport)
+{
+    if (QWebChannelTransportInterface *iface = qobject_cast<QWebChannelTransportInterface*>(transport)) {
+        QWebChannel::disconnectFrom(iface);
+        disconnect(transport, SIGNAL(destroyed(QObject*)), this, SLOT(transportDestroyed(QObject*)));
+        m_connectedObjects.remove(transport);
+    } else {
+        qWarning() << "Cannot disconnect from transport" << transport << " - it does not implement the QWebChannelTransportInterface.";
+    }
+}
+
+void QmlWebChannel::transportDestroyed(QObject *transport)
+{
+    QWebChannelTransportInterface *iface = m_connectedObjects.take(transport);
+    const int idx = d->transports.indexOf(iface);
+    if (idx != -1) {
+        d->transports.remove(idx);
+    }
+}
+
 QQmlListProperty<QObject> QmlWebChannel::registeredObjects()
 {
     return QQmlListProperty<QObject>(this, 0,
@@ -144,3 +174,37 @@ void QmlWebChannel::registeredObjects_clear(QQmlListProperty<QObject> *prop)
     }
     return channel->m_registeredObjects.clear();
 }
+
+QQmlListProperty<QWebChannelTransportInterface> QmlWebChannel::transports()
+{
+    return QQmlListProperty<QWebChannelTransportInterface>(this, 0,
+                                                           transports_append,
+                                                           transports_count,
+                                                           transports_at,
+                                                           transports_clear);
+}
+
+void QmlWebChannel::transports_append(QQmlListProperty<QWebChannelTransportInterface> *prop, QWebChannelTransportInterface *transport)
+{
+    QWebChannel *channel = static_cast<QWebChannel*>(prop->object);
+    channel->connectTo(transport);
+}
+
+int QmlWebChannel::transports_count(QQmlListProperty<QWebChannelTransportInterface> *prop)
+{
+    return static_cast<QmlWebChannel*>(prop->object)->d->transports.size();
+}
+
+QWebChannelTransportInterface *QmlWebChannel::transports_at(QQmlListProperty<QWebChannelTransportInterface> *prop, int index)
+{
+    return static_cast<QmlWebChannel*>(prop->object)->d->transports.at(index);
+}
+
+void QmlWebChannel::transports_clear(QQmlListProperty<QWebChannelTransportInterface> *prop)
+{
+    QWebChannel *channel = static_cast<QWebChannel*>(prop->object);
+    foreach (QWebChannelTransportInterface *transport, channel->d->transports) {
+        channel->disconnectFrom(transport);
+    }
+    Q_ASSERT(channel->d->transports.isEmpty());
+}
diff --git a/src/imports/webchannel/qmlwebchannel.h b/src/imports/webchannel/qmlwebchannel.h
index bcbb9cf..c45796f 100644
--- a/src/imports/webchannel/qmlwebchannel.h
+++ b/src/imports/webchannel/qmlwebchannel.h
@@ -45,6 +45,7 @@
 #include <qwebchannel.h>
 
 #include "qmlwebchannelattached.h"
+#include "qwebchanneltransportinterface.h"
 
 #include <QVector>
 
@@ -53,13 +54,13 @@
 
 QT_BEGIN_NAMESPACE
 
-class QmlWebChannelAttached;
-
 class QmlWebChannel : public QWebChannel
 {
     Q_OBJECT
 
+    Q_PROPERTY( QQmlListProperty<QWebChannelTransportInterface> connections READ transports );
     Q_PROPERTY( QQmlListProperty<QObject> registeredObjects READ registeredObjects )
+
 public:
     QmlWebChannel(QObject *parent = 0);
     virtual ~QmlWebChannel();
@@ -67,13 +68,19 @@ public:
     Q_INVOKABLE void registerObjects(const QVariantMap& objects);
     QQmlListProperty<QObject> registeredObjects();
 
+    QQmlListProperty<QWebChannelTransportInterface> transports();
+
     // TODO: remove this by replacing QML with C++ tests
     Q_INVOKABLE bool test_clientIsIdle() const;
 
     static QmlWebChannelAttached* qmlAttachedProperties(QObject *obj);
 
+    Q_INVOKABLE void connectTo(QObject *transport);
+    Q_INVOKABLE void disconnectFrom(QObject *transport);
+
 private slots:
     void objectIdChanged(const QString &newId);
+    void transportDestroyed(QObject *transport);
 
 private:
     static void registeredObjects_append(QQmlListProperty<QObject> *prop, QObject* item);
@@ -81,7 +88,14 @@ private:
     static QObject *registeredObjects_at(QQmlListProperty<QObject> *prop, int index);
     static void registeredObjects_clear(QQmlListProperty<QObject> *prop);
 
+    static void transports_append(QQmlListProperty<QWebChannelTransportInterface> *prop, QWebChannelTransportInterface* item);
+    static int transports_count(QQmlListProperty<QWebChannelTransportInterface> *prop);
+    static QWebChannelTransportInterface *transports_at(QQmlListProperty<QWebChannelTransportInterface> *prop, int index);
+    static void transports_clear(QQmlListProperty<QWebChannelTransportInterface> *prop);
+
     QVector<QObject*> m_registeredObjects;
+    // required as when the object is destroyed, we must still find the address of the base class somehow
+    QHash<QObject*, QWebChannelTransportInterface*> m_connectedObjects;
 };
 
 QML_DECLARE_TYPE( QmlWebChannel )
diff --git a/src/imports/webchannel/qmlwebviewtransport.cpp b/src/imports/webchannel/qmlwebviewtransport.cpp
new file mode 100644
index 0000000..7fb9d16
--- /dev/null
+++ b/src/imports/webchannel/qmlwebviewtransport.cpp
@@ -0,0 +1,103 @@
+/****************************************************************************
+**
+** 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.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: 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.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qmlwebviewtransport.h"
+
+#include <QVariantMap>
+
+QT_USE_NAMESPACE
+
+QmlWebViewTransport::QmlWebViewTransport(QObject *parent)
+    : QObject(parent)
+    , m_webViewExperimental(Q_NULLPTR)
+    , m_handler(Q_NULLPTR)
+{
+}
+
+QmlWebViewTransport::~QmlWebViewTransport()
+{
+
+}
+
+void QmlWebViewTransport::setWebViewExperimental(QObject *webViewExperimental)
+{
+    if (webViewExperimental != m_webViewExperimental) {
+        if (m_webViewExperimental) {
+            disconnect(m_webViewExperimental, 0, this, 0);
+        }
+        m_webViewExperimental = webViewExperimental;
+        connect(m_webViewExperimental, SIGNAL(messageReceived(QVariantMap)), this, SLOT(handleWebViewMessage(QVariantMap)));
+        emit webViewChanged(webViewExperimental);
+    }
+}
+
+QObject *QmlWebViewTransport::webViewExperimental() const
+{
+    return m_webViewExperimental;
+}
+
+void QmlWebViewTransport::sendMessage(const QString &message) const
+{
+    if (!m_webViewExperimental) {
+        qWarning("Cannot send message - did you forget to set the webViewExperimental property?");
+        return;
+    }
+    QMetaObject::invokeMethod(m_webViewExperimental, "postMessage", Q_ARG(QString, message));
+}
+
+void QmlWebViewTransport::sendMessage(const QByteArray &message) const
+{
+    sendMessage(QString::fromUtf8(message));
+}
+
+void QmlWebViewTransport::handleWebViewMessage(const QVariantMap &message)
+{
+    if (m_handler) {
+        const QString &data = message[QStringLiteral("data")].toString();
+        m_handler->handleMessage(data);
+        emit messageReceived(data);
+    }
+}
+
+void QmlWebViewTransport::setMessageHandler(QWebChannelMessageHandlerInterface *handler)
+{
+    m_handler = handler;
+}
diff --git a/src/imports/webchannel/qmlwebviewtransport.h b/src/imports/webchannel/qmlwebviewtransport.h
new file mode 100644
index 0000000..98dc504
--- /dev/null
+++ b/src/imports/webchannel/qmlwebviewtransport.h
@@ -0,0 +1,79 @@
+/****************************************************************************
+**
+** 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.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: 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.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QMLWEBVIEWTRANSPORT_H
+#define QMLWEBVIEWTRANSPORT_H
+
+#include <qwebchanneltransportinterface.h>
+
+QT_BEGIN_NAMESPACE
+
+class QmlWebViewTransport : public QObject, public QWebChannelTransportInterface
+{
+    Q_OBJECT
+    Q_INTERFACES(QWebChannelTransportInterface)
+    Q_PROPERTY(QObject *webViewExperimental READ webViewExperimental WRITE setWebViewExperimental NOTIFY webViewChanged)
+public:
+    explicit QmlWebViewTransport(QObject *parent = 0);
+    ~QmlWebViewTransport() Q_DECL_OVERRIDE;
+
+    void sendMessage(const QString &message) const Q_DECL_OVERRIDE;
+    void sendMessage(const QByteArray &message) const Q_DECL_OVERRIDE;
+    void setMessageHandler(QWebChannelMessageHandlerInterface *handler) Q_DECL_OVERRIDE;
+
+    void setWebViewExperimental(QObject *webViewExperimental);
+    QObject *webViewExperimental() const;
+
+signals:
+    void webViewChanged(QObject *webViewExperimental);
+    void messageReceived(const QString &message);
+
+private slots:
+    void handleWebViewMessage(const QVariantMap &message);
+
+private:
+    QObject *m_webViewExperimental;
+    QWebChannelMessageHandlerInterface *m_handler;
+};
+
+QT_END_NAMESPACE
+
+#endif // QMLWEBVIEWTRANSPORT_H
diff --git a/src/imports/webchannel/webchannel.pro b/src/imports/webchannel/webchannel.pro
index c1959f5..3042854 100644
--- a/src/imports/webchannel/webchannel.pro
+++ b/src/imports/webchannel/webchannel.pro
@@ -6,10 +6,12 @@ VPATH += ../../webchannel
 SOURCES += \
     plugin.cpp \
     qmlwebchannel.cpp \
-    qmlwebchannelattached.cpp
+    qmlwebchannelattached.cpp \
+    qmlwebviewtransport.cpp
 
 HEADERS += \
     qmlwebchannel.h \
-    qmlwebchannelattached.h
+    qmlwebchannelattached.h \
+    qmlwebviewtransport.h
 
 load(qml_plugin)
diff --git a/src/webchannel/qmetaobjectpublisher.cpp b/src/webchannel/qmetaobjectpublisher.cpp
index bd2a22b..1ac3ad9 100644
--- a/src/webchannel/qmetaobjectpublisher.cpp
+++ b/src/webchannel/qmetaobjectpublisher.cpp
@@ -524,7 +524,7 @@ bool QMetaObjectPublisher::handleRequest(const QJsonObject &message)
     return false;
 }
 
-void QMetaObjectPublisher::handleRawMessage(const QString &message)
+void QMetaObjectPublisher::handleMessage(const QString &message)
 {
     const QJsonDocument doc = QJsonDocument::fromJson(message.toUtf8());
     if (doc.isObject()) {
diff --git a/src/webchannel/qmetaobjectpublisher_p.h b/src/webchannel/qmetaobjectpublisher_p.h
index 3e80d24..ff077e7 100644
--- a/src/webchannel/qmetaobjectpublisher_p.h
+++ b/src/webchannel/qmetaobjectpublisher_p.h
@@ -50,16 +50,17 @@
 #include <QBasicTimer>
 #include <QPointer>
 
+#include "qwebchannelglobal.h"
+#include "qwebchanneltransportinterface.h"
+
 QT_BEGIN_NAMESPACE
 
 class QWebChannel;
 
-#include "qwebchannelglobal.h"
-
-class Q_WEBCHANNEL_EXPORT QMetaObjectPublisher : public QObject
+class Q_WEBCHANNEL_EXPORT QMetaObjectPublisher : public QObject, public QWebChannelMessageHandlerInterface
 {
     Q_OBJECT
-
+    Q_INTERFACES(QWebChannelMessageHandlerInterface)
 public:
     QMetaObjectPublisher(QWebChannel *webChannel);
     virtual ~QMetaObjectPublisher();
@@ -160,14 +161,10 @@ public:
      */
     void setBlockUpdates(bool block);
 
-public slots:
     /**
-     * Helper slot which you can connect directly to WebChannel's rawMessageReceived signal.
-     *
-     * This slot then tries to parse the message as JSON and if it succeeds, calls handleRequest
-     * with the obtained JSON object.
+     * Parse the message as JSON and if it succeeds, call handleRequest with the obtained JSON object.
      */
-    void handleRawMessage(const QString &message);
+    void handleMessage(const QString &message) Q_DECL_OVERRIDE;
 
 signals:
     void blockUpdatesChanged(bool block);
diff --git a/src/webchannel/qwebchannel.cpp b/src/webchannel/qwebchannel.cpp
index b51a056..a080aae 100644
--- a/src/webchannel/qwebchannel.cpp
+++ b/src/webchannel/qwebchannel.cpp
@@ -43,7 +43,7 @@
 #include "qwebchannel.h"
 #include "qwebchannel_p.h"
 #include "qmetaobjectpublisher_p.h"
-#include "qwebchannelsocket_p.h"
+#include "qwebchanneltransportinterface.h"
 
 #include <QJsonDocument>
 #include <QJsonObject>
@@ -52,6 +52,11 @@ QT_BEGIN_NAMESPACE
 
 void QWebChannelPrivate::sendJSONMessage(const QJsonValue &id, const QJsonValue &data, bool response) const
 {
+    if (transports.isEmpty()) {
+        qWarning("QWebChannel is not connected to any transports, cannot send messages.");
+        return;
+    }
+
     QJsonObject obj;
     if (response) {
         obj[QStringLiteral("response")] = true;
@@ -61,55 +66,27 @@ void QWebChannelPrivate::sendJSONMessage(const QJsonValue &id, const QJsonValue
         obj[QStringLiteral("data")] = data;
     }
     QJsonDocument doc(obj);
-    socket->sendMessage(doc.toJson(QJsonDocument::Compact));
+    const QByteArray &message = doc.toJson(QJsonDocument::Compact);
+
+    foreach (QWebChannelTransportInterface *transport, transports) {
+        transport->sendMessage(message);
+    }
 }
 
 QWebChannel::QWebChannel(QObject *parent)
 : QObject(parent)
 , d(new QWebChannelPrivate)
 {
-    d->socket = new QWebChannelSocket(this);
-
-    connect(d->socket, SIGNAL(textDataReceived(QString)),
-            SIGNAL(rawMessageReceived(QString)));
-    connect(d->socket, SIGNAL(failed(QString)),
-            SIGNAL(failed(QString)));
-    connect(d->socket, SIGNAL(initialized()),
-            SIGNAL(initialized()));
-    connect(d->socket, SIGNAL(baseUrlChanged(QString)),
-            SIGNAL(baseUrlChanged(QString)));
-    connect(d->socket, SIGNAL(pongReceived()),
-            SIGNAL(pongReceived()));
-
-    d->socket->initLater();
-
     d->publisher = new QMetaObjectPublisher(this);
     connect(d->publisher, SIGNAL(blockUpdatesChanged(bool)),
             SIGNAL(blockUpdatesChanged(bool)));
-    connect(d->socket, SIGNAL(textDataReceived(QString)),
-            d->publisher, SLOT(handleRawMessage(QString)));
 }
 
 QWebChannel::~QWebChannel()
 {
-}
-
-QString QWebChannel::baseUrl() const
-{
-    return d->socket->m_baseUrl;
-}
-
-void QWebChannel::setUseSecret(bool s)
-{
-    if (d->socket->m_useSecret == s)
-        return;
-    d->socket->m_useSecret = s;
-    d->socket->initLater();
-}
-
-bool QWebChannel::useSecret() const
-{
-    return d->socket->m_useSecret;
+    foreach (QWebChannelTransportInterface *transport, d->transports) {
+        transport->setMessageHandler(Q_NULLPTR);
+    }
 }
 
 void QWebChannel::registerObjects(const QHash< QString, QObject * > &objects)
@@ -141,24 +118,32 @@ void QWebChannel::setBlockUpdates(bool block)
     d->publisher->setBlockUpdates(block);
 }
 
-void QWebChannel::respond(const QJsonValue& messageId, const QJsonValue& data) const
+void QWebChannel::connectTo(QWebChannelTransportInterface *transport)
 {
-    d->sendJSONMessage(messageId, data, true);
+    Q_ASSERT(transport);
+    if (!d->transports.contains(transport)) {
+        d->transports << transport;
+        transport->setMessageHandler(d->publisher);
+    }
 }
 
-void QWebChannel::sendMessage(const QJsonValue& id, const QJsonValue& data) const
+void QWebChannel::disconnectFrom(QWebChannelTransportInterface *transport)
 {
-    d->sendJSONMessage(id, data, false);
+    const int idx = d->transports.indexOf(transport);
+    if (idx != -1) {
+        transport->setMessageHandler(Q_NULLPTR);
+        d->transports.remove(idx);
+    }
 }
 
-void QWebChannel::sendRawMessage(const QString& message) const
+void QWebChannel::respond(const QJsonValue& messageId, const QJsonValue& data) const
 {
-    d->socket->sendMessage(message.toUtf8());
+    d->sendJSONMessage(messageId, data, true);
 }
 
-void QWebChannel::ping() const
+void QWebChannel::sendMessage(const QJsonValue& id, const QJsonValue& data) const
 {
-    d->socket->ping();
+    d->sendJSONMessage(id, data, false);
 }
 
 QT_END_NAMESPACE
diff --git a/src/webchannel/qwebchannel.h b/src/webchannel/qwebchannel.h
index bf9c5fd..f6965e0 100644
--- a/src/webchannel/qwebchannel.h
+++ b/src/webchannel/qwebchannel.h
@@ -51,24 +51,17 @@
 QT_BEGIN_NAMESPACE
 
 struct QWebChannelPrivate;
+class QWebChannelTransportInterface;
 
 class Q_WEBCHANNEL_EXPORT QWebChannel : public QObject
 {
     Q_OBJECT
     Q_DISABLE_COPY(QWebChannel)
-    Q_PROPERTY(QString baseUrl READ baseUrl NOTIFY baseUrlChanged)
-    Q_PROPERTY(bool useSecret READ useSecret WRITE setUseSecret)
     Q_PROPERTY(bool blockUpdates READ blockUpdates WRITE setBlockUpdates NOTIFY blockUpdatesChanged);
-
 public:
     QWebChannel(QObject *parent = 0);
     ~QWebChannel();
 
-    QString baseUrl() const;
-
-    void setUseSecret(bool);
-    bool useSecret() const;
-
     /**
      * Register a map of string ID to QObject* objects.
      *
@@ -96,21 +89,15 @@ public:
      */
     void setBlockUpdates(bool block);
 
-signals:
-    void baseUrlChanged(const QString& baseUrl);
-    void rawMessageReceived(const QString& rawMessage);
-    void pongReceived();
-    void initialized();
-
-    void failed(const QString& reason);
+    void connectTo(QWebChannelTransportInterface *transport);
+    void disconnectFrom(QWebChannelTransportInterface *transport);
 
+signals:
     void blockUpdatesChanged(bool block);
 
 public slots:
     void sendMessage(const QJsonValue& id, const QJsonValue& data = QJsonValue()) const;
     void respond(const QJsonValue& messageId, const QJsonValue& data = QJsonValue()) const;
-    void sendRawMessage(const QString& rawMessage) const;
-    void ping() const;
 
 private:
     QScopedPointer<QWebChannelPrivate> d;
diff --git a/src/webchannel/qwebchannel.js b/src/webchannel/qwebchannel.js
index 5ca051c..887c5a0 100644
--- a/src/webchannel/qwebchannel.js
+++ b/src/webchannel/qwebchannel.js
@@ -42,7 +42,7 @@
 
 "use strict";
 
-var QWebChannel = function(baseUrl, initCallback, rawChannel)
+var QWebChannel = function(baseUrlOrSocket, initCallback, rawChannel)
 {
     var channel = this;
     // support multiple channels listening to the same socket
@@ -52,34 +52,14 @@ var QWebChannel = function(baseUrl, initCallback, rawChannel)
         var r = Math.random()*16|0, v = c == 'x' ? r : (r&0x3|0x8);
         return v.toString(16);
     });
-    ///TODO: use ssl?
-    var socketUrl = "ws://" + baseUrl;
-    this.socket = new WebSocket(socketUrl, "QWebChannel");
     this.send = function(data)
     {
         if (typeof(data) !== "string") {
             data = JSON.stringify(data);
         }
         channel.socket.send(data);
-    };
-
-    this.socket.onopen = function()
-    {
-        if (rawChannel) {
-            initCallback(channel);
-        } else {
-            channel.initMetaObjectPublisher(initCallback);
-        }
-    };
-    this.socket.onclose = function()
-    {
-        console.error("web channel closed");
-    };
-    this.socket.onerror = function(error)
-    {
-        console.error("web channel error: " + error);
-    };
-    this.socket.onmessage = function(message)
+    }
+    this.messageReceived = function(message)
     {
         var jsonData = JSON.parse(message.data);
         if (jsonData.id === undefined) {
@@ -99,7 +79,41 @@ var QWebChannel = function(baseUrl, initCallback, rawChannel)
                 (callback)(jsonData.data); }
             );
         }
-    };
+    }
+
+    this.initialized = function()
+    {
+        if (rawChannel) {
+            initCallback(channel);
+        } else {
+            channel.initMetaObjectPublisher(initCallback);
+        }
+    }
+
+    if (typeof baseUrlOrSocket === 'object') {
+        this.socket = baseUrlOrSocket;
+        this.socket.send = function(data)
+        {
+            channel.socket.postMessage(data);
+        }
+        this.socket.onmessage = this.messageReceived
+        setTimeout(this.initialized, 0);
+    } else {
+        ///TODO: use ssl?
+        var socketUrl = "ws://" + baseUrlOrSocket;
+        this.socket = new WebSocket(socketUrl, "QWebChannel");
+
+        this.socket.onopen = this.initialized
+        this.socket.onclose = function()
+        {
+            console.error("web channel closed");
+        };
+        this.socket.onerror = function(error)
+        {
+            console.error("web channel error: " + error);
+        };
+        this.socket.onmessage = this.messageReceived
+    }
 
     this.subscriptions = {};
     this.subscribe = function(id, callback)
@@ -136,7 +150,6 @@ var QWebChannel = function(baseUrl, initCallback, rawChannel)
         // prevent multiple initialization which might happen with multiple webchannel clients.
         var initialized = false;
 
-        console.log(channel);
         channel.subscribe(
             "Qt.signal",
             function(payload) {
diff --git a/src/webchannel/qwebchannel_p.h b/src/webchannel/qwebchannel_p.h
index 63f5a0a..954134e 100644
--- a/src/webchannel/qwebchannel_p.h
+++ b/src/webchannel/qwebchannel_p.h
@@ -43,16 +43,19 @@
 #define QWEBCHANNEL_P_H
 
 #include "qwebchannelglobal.h"
+#include "qwebchanneltransportinterface.h"
+
+#include <QVector>
 
 QT_BEGIN_NAMESPACE
 
 class QJsonValue;
-class QWebChannelSocket;
+class QWebChannelTransportInterface;
 class QMetaObjectPublisher;
 
 struct Q_WEBCHANNEL_EXPORT QWebChannelPrivate
 {
-    QWebChannelSocket *socket;
+    QVector<QWebChannelTransportInterface*> transports;
     QMetaObjectPublisher *publisher;
 
     void sendJSONMessage(const QJsonValue &id, const QJsonValue &data, bool response) const;
diff --git a/src/webchannel/qwebchannelsocket.cpp b/src/webchannel/qwebchannelsocket.cpp
index 84e6685..b3daf8f 100644
--- a/src/webchannel/qwebchannelsocket.cpp
+++ b/src/webchannel/qwebchannelsocket.cpp
@@ -48,11 +48,14 @@ QT_BEGIN_NAMESPACE
 
 QWebChannelSocket::QWebChannelSocket(QObject *parent)
     : QWebSocketServer(parent)
+    , m_messageHandler(Q_NULLPTR)
     , m_useSecret(true)
     , m_starting(false)
 {
     connect(this, SIGNAL(error(QAbstractSocket::SocketError)),
             SLOT(socketError()));
+    connect(this, SIGNAL(textDataReceived(QString)),
+            SLOT(messageReceived(QString)));
 }
 
 void QWebChannelSocket::initLater()
@@ -100,4 +103,11 @@ void QWebChannelSocket::socketError()
     emit failed(errorString());
 }
 
+void QWebChannelSocket::messageReceived(const QString &message)
+{
+    if (m_messageHandler) {
+        m_messageHandler->handleMessage(message);
+    }
+}
+
 QT_END_NAMESPACE
diff --git a/src/webchannel/qwebchannelsocket_p.h b/src/webchannel/qwebchannelsocket_p.h
index 3f58f91..9d6cde5 100644
--- a/src/webchannel/qwebchannelsocket_p.h
+++ b/src/webchannel/qwebchannelsocket_p.h
@@ -43,6 +43,7 @@
 #define QWEBCHANNELSOCKET_P_H
 
 #include "qwebsocketserver_p.h"
+#include "qwebchanneltransportinterface.h"
 
 QT_BEGIN_NAMESPACE
 
@@ -52,11 +53,12 @@ class QWebChannelSocket : public QWebSocketServer
 public:
     QByteArray m_secret;
     QString m_baseUrl;
+    QWebChannelMessageHandlerInterface *m_messageHandler;
 
     bool m_useSecret;
     bool m_starting;
 
-    QWebChannelSocket(QObject *parent);
+    explicit QWebChannelSocket(QObject *parent = 0);
 
     void initLater();
 
@@ -71,6 +73,7 @@ protected:
 private slots:
     void init();
     void socketError();
+    void messageReceived(const QString &message);
 };
 
 QT_END_NAMESPACE
diff --git a/src/webchannel/qwebchanneltransportinterface.h b/src/webchannel/qwebchanneltransportinterface.h
new file mode 100644
index 0000000..9044c68
--- /dev/null
+++ b/src/webchannel/qwebchanneltransportinterface.h
@@ -0,0 +1,93 @@
+/****************************************************************************
+**
+** 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.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: 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.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QWEBCHANNELTRANSPORTINTERFACE_H
+#define QWEBCHANNELTRANSPORTINTERFACE_H
+
+#include <QObject>
+
+#include <QtWebChannel/qwebchannelglobal.h>
+
+QT_BEGIN_NAMESPACE
+
+class Q_WEBCHANNEL_EXPORT QWebChannelMessageHandlerInterface
+{
+public:
+    virtual ~QWebChannelMessageHandlerInterface() {}
+
+    /**
+     * Handle a text message from a web channel client.
+     */
+    virtual void handleMessage(const QString &message) = 0;
+};
+
+#define QWebChannelMessageHandlerInterface_iid "org.qt-project.Qt.QWebChannelMessageHandlerInterface"
+Q_DECLARE_INTERFACE(QWebChannelMessageHandlerInterface, QWebChannelMessageHandlerInterface_iid);
+Q_DECLARE_METATYPE(QWebChannelMessageHandlerInterface*)
+
+class Q_WEBCHANNEL_EXPORT QWebChannelTransportInterface
+{
+public:
+    virtual ~QWebChannelTransportInterface() {}
+
+    /**
+     * Send a text message to all web channel clients.
+     */
+    virtual void sendMessage(const QString &message) const = 0;
+
+    /**
+     * Send a binary message to all web channel clients.
+     */
+    virtual void sendMessage(const QByteArray &message) const = 0;
+
+    /**
+     * Sets the message handler that will be called on incoming messages from web channel clients.
+     */
+    virtual void setMessageHandler(QWebChannelMessageHandlerInterface *handler) = 0;
+};
+
+#define QWebChannelTransportInterface_iid "org.qt-project.Qt.QWebChannelTransportInterface"
+Q_DECLARE_INTERFACE(QWebChannelTransportInterface, QWebChannelTransportInterface_iid);
+Q_DECLARE_METATYPE(QWebChannelTransportInterface*)
+
+QT_END_NAMESPACE
+
+#endif // QWEBCHANNELTRANSPORTINTERFACE_H
diff --git a/src/webchannel/qwebsocketserver.cpp b/src/webchannel/qwebsocketserver.cpp
index 4404dc1..5a5b5a7 100644
--- a/src/webchannel/qwebsocketserver.cpp
+++ b/src/webchannel/qwebsocketserver.cpp
@@ -387,6 +387,9 @@ void QWebSocketServer::sendMessage(const QByteArray& message) const
 
 void QWebSocketServer::sendFrame(Frame::Opcode opcode, const QByteArray& data) const
 {
+    if (m_connections.isEmpty()) {
+        return;
+    }
     const QByteArray& header = frameHeader(opcode, data.size());
     QHash< QTcpSocket*, Connection >::const_iterator it = m_connections.constBegin();
     while (it != m_connections.constEnd()) {
diff --git a/src/webchannel/qwebsockettransport.cpp b/src/webchannel/qwebsockettransport.cpp
new file mode 100644
index 0000000..be991a8
--- /dev/null
+++ b/src/webchannel/qwebsockettransport.cpp
@@ -0,0 +1,101 @@
+/****************************************************************************
+**
+** 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.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: 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.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qwebsockettransport.h"
+#include "qwebchannelsocket_p.h"
+
+QT_BEGIN_NAMESPACE
+
+QWebSocketTransport::QWebSocketTransport(QObject *parent)
+    : QObject(parent)
+    , d(new QWebChannelSocket)
+{
+    connect(d.data(), SIGNAL(textDataReceived(QString)),
+            SIGNAL(messageReceived(QString)));
+    connect(d.data(), SIGNAL(failed(QString)),
+            SIGNAL(failed(QString)));
+    connect(d.data(), SIGNAL(initialized()),
+            SIGNAL(initialized()));
+    connect(d.data(), SIGNAL(baseUrlChanged(QString)),
+            SIGNAL(baseUrlChanged(QString)));
+
+    d->initLater();
+}
+
+QWebSocketTransport::~QWebSocketTransport()
+{
+
+}
+
+void QWebSocketTransport::sendMessage(const QByteArray &message) const
+{
+    d->sendMessage(message);
+}
+
+void QWebSocketTransport::sendMessage(const QString &message) const
+{
+    d->sendMessage(message.toUtf8());
+}
+
+void QWebSocketTransport::setMessageHandler(QWebChannelMessageHandlerInterface *handler)
+{
+    d->m_messageHandler = handler;
+}
+
+QString QWebSocketTransport::baseUrl() const
+{
+    return d->m_baseUrl;
+}
+
+void QWebSocketTransport::setUseSecret(bool s)
+{
+    if (d->m_useSecret == s)
+        return;
+    d->m_useSecret = s;
+    d->initLater();
+}
+
+bool QWebSocketTransport::useSecret() const
+{
+    return d->m_useSecret;
+}
+
+QT_END_NAMESPACE
diff --git a/src/webchannel/qwebsockettransport.h b/src/webchannel/qwebsockettransport.h
new file mode 100644
index 0000000..d8d164a
--- /dev/null
+++ b/src/webchannel/qwebsockettransport.h
@@ -0,0 +1,81 @@
+/****************************************************************************
+**
+** 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.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: 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.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QWEBSOCKETTRANSPORT_H
+#define QWEBSOCKETTRANSPORT_H
+
+#include "qwebchanneltransportinterface.h"
+
+QT_BEGIN_NAMESPACE
+
+class QWebChannelSocket;
+class Q_WEBCHANNEL_EXPORT QWebSocketTransport : public QObject, public QWebChannelTransportInterface
+{
+    Q_OBJECT
+    Q_INTERFACES(QWebChannelTransportInterface)
+    Q_PROPERTY(QString baseUrl READ baseUrl NOTIFY baseUrlChanged)
+    Q_PROPERTY(bool useSecret READ useSecret WRITE setUseSecret)
+public:
+    explicit QWebSocketTransport(QObject *parent = 0);
+    ~QWebSocketTransport() Q_DECL_OVERRIDE;
+
+    void sendMessage(const QByteArray &message) const Q_DECL_OVERRIDE;
+    void sendMessage(const QString &message) const Q_DECL_OVERRIDE;
+    void setMessageHandler(QWebChannelMessageHandlerInterface *handler) Q_DECL_OVERRIDE;
+
+    QString baseUrl() const;
+
+    void setUseSecret(bool);
+    bool useSecret() const;
+
+Q_SIGNALS:
+    void baseUrlChanged(const QString &baseUrl);
+    void failed(const QString &reason);
+    void initialized();
+    void messageReceived(const QString &message);
+
+private:
+    QScopedPointer<QWebChannelSocket> d;
+};
+
+QT_END_NAMESPACE
+
+#endif // QWEBSOCKETTRANSPORT_H
diff --git a/src/webchannel/webchannel.pro b/src/webchannel/webchannel.pro
index 36cd686..279eb37 100644
--- a/src/webchannel/webchannel.pro
+++ b/src/webchannel/webchannel.pro
@@ -11,7 +11,9 @@ OTHER_FILES = \
     qwebchannel.js
 
 PUBLIC_HEADERS += \
-    qwebchannel.h
+    qwebchannel.h \
+    qwebchanneltransport.h \
+    qwebsockettransport.h
 
 PRIVATE_HEADERS += \
     qwebchannel_p.h \
@@ -25,7 +27,8 @@ SOURCES += \
     qwebchannel.cpp \
     qmetaobjectpublisher.cpp \
     qwebsocketserver.cpp \
-    qwebchannelsocket.cpp
+    qwebchannelsocket.cpp \
+    qwebsockettransport.cpp
 
 qtHaveModule(qml) {
     QT += qml