Introduce messageserver plugins.4.0.2

MessageServer plugins will be loaded and executed in the messageserver main loop,
these plugins should only be used for services that need to know information
about the operations initiated by all clients connected to messageserver.

To make use of this functionality qmf should be compiled with 'DEFINES+=MESSAGESERVER_PLUGINS'.

Change-Id: I6bebb150645d2c70a5bc67ffcaaa904f94ed3705
Signed-off-by: Valerio Valerio <valerio.valerio@jollamobile.com>
Reviewed-by: Robin Burchell <robin+qt@viroteck.net>

5 files changed, 261 insertions, 2 deletions

diff --git a/src/libraries/qmfmessageserver/qmailmessageserverplugin.cpp b/src/libraries/qmfmessageserver/qmailmessageserverplugin.cpp
new file mode 100644
index 00000000..0fa857b7
--- /dev/null
+++ b/src/libraries/qmfmessageserver/qmailmessageserverplugin.cpp
@@ -0,0 +1,170 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Jolla Ltd.
+** Contact: Valério Valério <valerio.valerio@jollamobile.com>
+**
+** This file is part of the Qt Messaging Framework.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 "qmailmessageserverplugin.h"
+#include <qmailpluginmanager.h>
+#include <QDebug>
+
+#define PLUGIN_KEY "messageserverplugins"
+
+typedef QMap<QString, QMailMessageServerPlugin*> PluginMap;
+
+/*! \internal
+    Load all the plugins into a map for quicker reference
+*/
+static PluginMap initMap(QMailPluginManager& manager)
+{
+    PluginMap map;
+
+    foreach (const QString &item, manager.list()) {
+        QObject *instance = manager.instance(item);
+        if (QMailMessageServerPlugin* iface = qobject_cast<QMailMessageServerPlugin*>(instance))
+                map.insert(iface->key(), iface);
+    }
+    return map;
+}
+/*! \internal
+    Return a reference to a map containing all loaded plugin objects
+*/
+static PluginMap& pluginMap()
+{
+    static QMailPluginManager pluginManager(PLUGIN_KEY);
+    static PluginMap map(initMap(pluginManager));
+
+    return map;
+}
+
+/*! \internal
+    Return the plugin object matching the specified ID
+*/
+static QMailMessageServerPlugin* mapping(const QString& key)
+{
+    PluginMap::ConstIterator it;
+    if ((it = pluginMap().find(key)) != pluginMap().end())
+        return it.value();
+
+    qWarning() << "Failed attempt to map plugin: " << key;
+    return 0;
+}
+
+/*!
+    \class QMailMessageServerPlugin
+    \ingroup libmessageserver
+
+    \brief The QMailMessageServerPlugin class defines the interface to plugins that provide additional services
+    for the messageserver daemon.
+
+    The QMailMessageServerPlugin class defines the interface to messageserver plugins.  Plugins will
+    be loaded and executed in the messageserver main loop, these plugins should only be used for services
+    that need to be informed about operations initiated by all clients connected to messageserver.
+
+    \sa QMailMessageServerPluginFactory
+*/
+
+/*!
+    \fn QString QMailMessageServerPlugin::key() const
+
+    Returns a string identifying the plugin.
+*/
+
+/*!
+    \fn QString QMailMessageServerPlugin::exec()
+
+    The starting point for the plugin.
+    Plugin implementations should use this function as execution
+    entry point for the service(s) provided by the plugin.
+*/
+
+/*!
+    \fn QMailMessageServerPlugin* QMailMessageServerPlugin::createService()
+
+    Creates an instance of the service provided by the plugin.
+*/
+
+
+QMailMessageServerPlugin::QMailMessageServerPlugin(QObject *parent)
+    : QObject(parent)
+{
+}
+
+QMailMessageServerPlugin::~QMailMessageServerPlugin()
+{
+}
+
+/*!
+    \class QMailMessageServerPluginFactory
+    \ingroup libmessageserver
+
+    \brief The QMailMessageServerPluginFactory class creates objects implementing the QMailMessageServerPlugin interface.
+
+    The QMailMessageServerPluginFactory class creates objects that provide plugins services to the
+    messageserver daemon. The factory allows implementations to be loaded from plugin libraries,
+    and to be retrieved and instantiated by name.
+
+    To create a new service that can be created via the QMailMessageServerPluginFactory, derive from the
+    QMailMessageServerPlugin base class.
+
+    \sa QMailMessageServerPlugin
+*/
+
+/*!
+    Returns a list of the keys of the installed plugins.
+ */
+QStringList QMailMessageServerPluginFactory::keys()
+{
+    QStringList in;
+
+    foreach (PluginMap::mapped_type plugin, pluginMap())
+        in << plugin->key();
+
+    return in;
+}
+
+/*!
+    Creates a plugin object of the class identified by \a key.
+*/
+QMailMessageServerPlugin* QMailMessageServerPluginFactory::createService(const QString& key)
+{
+    if (QMailMessageServerPlugin* plugin = mapping(key))
+        return plugin->createService();
+
+    return 0;
+}
diff --git a/src/libraries/qmfmessageserver/qmailmessageserverplugin.h b/src/libraries/qmfmessageserver/qmailmessageserverplugin.h
new file mode 100644
index 00000000..1f1413ef
--- /dev/null
+++ b/src/libraries/qmfmessageserver/qmailmessageserverplugin.h
@@ -0,0 +1,68 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Jolla Ltd.
+** Contact: Valério Valério <valerio.valerio@jollamobile.com>
+**
+** This file is part of the Qt Messaging Framework.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 QMAILMESSAGESERVERPLUGIN_H
+#define QMAILMESSAGESERVERPLUGIN_H
+
+#include "qmailglobal.h"
+#include <QObject>
+
+class MESSAGESERVER_EXPORT QMailMessageServerPlugin : public QObject
+{
+    Q_OBJECT
+
+public:
+    QMailMessageServerPlugin(QObject* parent = 0);
+    ~QMailMessageServerPlugin();
+
+    virtual QString key() const = 0;
+    virtual void exec() = 0;
+    virtual QMailMessageServerPlugin *createService() = 0;
+};
+
+class MESSAGESERVER_EXPORT QMailMessageServerPluginFactory
+{
+public:
+    static QStringList keys();
+    static QMailMessageServerPlugin *createService(const QString& key);
+};
+
+#endif // QMAILMESSAGESERVERPLUGIN_H
diff --git a/src/libraries/qmfmessageserver/qmfmessageserver.pro b/src/libraries/qmfmessageserver/qmfmessageserver.pro
index ccfcb508..768b5e6d 100644
--- a/src/libraries/qmfmessageserver/qmfmessageserver.pro
+++ b/src/libraries/qmfmessageserver/qmfmessageserver.pro
@@ -37,8 +37,6 @@ PUBLIC_HEADERS += qmailauthenticator.h \
                   qmailtransport.h \
                   qmailheartbeattimer.h
 
-HEADERS += $$PUBLIC_HEADERS $$PRIVATE_HEADERS
-
 SOURCES += qmailauthenticator.cpp \
            qmailmessagebuffer.cpp \
            qmailmessageclassifier.cpp \
@@ -48,6 +46,13 @@ SOURCES += qmailauthenticator.cpp \
            qmailtransport.cpp \
            qmailheartbeattimer_qtimer.cpp # NB: There are multiple implementations
 
+contains(DEFINES,MESSAGESERVER_PLUGINS) {
+    PUBLIC_HEADERS += qmailmessageserverplugin.h
+    SOURCES += qmailmessageserverplugin.cpp
+}
+
+HEADERS += $$PUBLIC_HEADERS $$PRIVATE_HEADERS
+
 equals(QT_MAJOR_VERSION, 4): header_files.path=$$QMF_INSTALL_ROOT/include/qmfmessageserver
 equals(QT_MAJOR_VERSION, 5): header_files.path=$$QMF_INSTALL_ROOT/include/qmfmessageserver5
 header_files.files=$$PUBLIC_HEADERS
diff --git a/src/tools/messageserver/messageserver.cpp b/src/tools/messageserver/messageserver.cpp
index da2b47dd..43a61d66 100644
--- a/src/tools/messageserver/messageserver.cpp
+++ b/src/tools/messageserver/messageserver.cpp
@@ -51,6 +51,7 @@
 #include <qmailipc.h>
 #include <newcountnotifier.h>
 #include <qcopserver.h>
+#include <qmailmessageserverplugin.h>
 
 extern "C" {
 #ifndef Q_OS_WIN
@@ -59,6 +60,10 @@ extern "C" {
 #include <signal.h>
 }
 
+#ifdef MESSAGESERVER_PLUGINS
+#include "messageserverplugins.h"
+#endif
+
 #if defined(Q_OS_UNIX)
 int MessageServer::sighupFd[2];
 #endif
@@ -252,6 +257,16 @@ MessageServer::MessageServer(QObject *parent)
 
         emit client->actionsListed(QMailActionDataList());
     }
+
+#ifdef MESSAGESERVER_PLUGINS
+    qMailLog(Messaging) << "Initiating messageserver plugins.";
+    QStringList availablePlugins = QMailMessageServerPluginFactory::keys();
+
+    for (int i = 0; i < availablePlugins.size(); i++) {
+        QMailMessageServerPlugin *plugin = QMailMessageServerPluginFactory::createService(availablePlugins.at(i));
+        plugin->exec();
+    }
+#endif
 }
 
 MessageServer::~MessageServer()
diff --git a/src/tools/messageserver/messageserver.pro b/src/tools/messageserver/messageserver.pro
index fcfe535a..e4202bb4 100644
--- a/src/tools/messageserver/messageserver.pro
+++ b/src/tools/messageserver/messageserver.pro
@@ -46,6 +46,7 @@ SOURCES += mailmessageclient.cpp \
            prepareaccounts.cpp \
            newcountnotifier.cpp \
            servicehandler.cpp
+
 !SERVER_AS_DLL: {
     SOURCES += main.cpp
 }