[kwin] Use KPluginTrader and json metadata to find KDecorations

* A KDecoration needs to include json metadata
* A KDecoration needs to be installed to kwin/kdecorations
* Aurorae and Oxygen adjusted
* kcmdeco locates all decorations through the KPluginTrader
* libkdecoration uses KPluginTrader to find the plugin
* config plugins also need to include json metadata with
  X-KDE-PluginInfo-Name being the same as the decoration
* config plugins need to get installed to kwin/kdecorations/config
* kcmdeco locates the config plugin for a deco through the name
  and KPluginTrader

REVIEW: 116765

clients/aurorae/src/CMakeLists.txt

@@ -22,7 +22,9 @@ target_link_libraries(kwin3_aurorae
     kdecorations
 )
 
-install(TARGETS kwin3_aurorae  DESTINATION ${PLUGIN_INSTALL_DIR} )
+kservice_desktop_to_json(kwin3_aurorae aurorae.desktop)
+
+install(TARGETS kwin3_aurorae  DESTINATION ${PLUGIN_INSTALL_DIR}/kwin/kdecorations )
 
 set(decoration_plugin_SRCS
     decorationplugin.cpp
@@ -41,7 +43,6 @@ install(TARGETS decorationplugin DESTINATION ${QML_INSTALL_DIR}/org/kde/kwin/dec
 
 ########### install files ###############
 
-install( FILES aurorae.desktop  DESTINATION  ${DATA_INSTALL_DIR}/kwin )
 install( FILES aurorae.knsrc  DESTINATION  ${CONFIG_INSTALL_DIR} )
 install( FILES
     qml/aurorae.qml

clients/aurorae/src/aurorae.cpp

@@ -37,8 +37,9 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <KPluginInfo>
 #include <KServiceTypeTrader>
 
-K_PLUGIN_FACTORY(AuroraePluginFactory,
+K_PLUGIN_FACTORY_WITH_JSON(AuroraePluginFactory,
-                 registerPlugin<Aurorae::AuroraeFactory>(QString(), &Aurorae::AuroraeFactory::createInstance);)
+                           "aurorae.json",
+                           registerPlugin<Aurorae::AuroraeFactory>(QString(), &Aurorae::AuroraeFactory::createInstance);)
 K_EXPORT_PLUGIN_VERSION(KWIN_DECORATION_API_VERSION)
 
 namespace Aurorae

clients/aurorae/src/aurorae.desktop

@@ -65,4 +65,4 @@ Name[wa]=Moteur di tinme di gåyotaedje Aurorae
 Name[x-test]=xxAurorae Decoration Theme Enginexx
 Name[zh_CN]=Aurorae 装饰主题引擎
 Name[zh_TW]=Aurorae 裝飾主題引擎
-X-KDE-Library=kwin3_aurorae
+X-KDE-PluginInfo-Name=aurorae

clients/oxygen/CMakeLists.txt

@@ -30,11 +30,10 @@ target_link_libraries(kwin3_oxygen kdecorations)
 
 target_link_libraries(kwin3_oxygen oxygenstyle)
 
+kservice_desktop_to_json(kwin3_oxygen oxygenclient.desktop)
+
 if(X11_FOUND)
   target_link_libraries(kwin3_oxygen XCB::XCB)
 endif()
 
-install(TARGETS kwin3_oxygen  DESTINATION ${PLUGIN_INSTALL_DIR})
+install(TARGETS kwin3_oxygen  DESTINATION ${PLUGIN_INSTALL_DIR}/kwin/kdecorations)
-
-########### install files ###############
-install(FILES oxygenclient.desktop  DESTINATION  ${DATA_INSTALL_DIR}/kwin/)

clients/oxygen/config/CMakeLists.txt

@@ -34,4 +34,4 @@ if(X11_FOUND)
   target_link_libraries(kwin_oxygen_config Qt5::X11Extras)
 endif()
 
-install(TARGETS kwin_oxygen_config DESTINATION ${QT_PLUGIN_INSTALL_DIR}/kf5)
+install(TARGETS kwin_oxygen_config DESTINATION ${QT_PLUGIN_INSTALL_DIR}/kf5/kwin/kdecorations/config)

clients/oxygen/config/config.json

@@ -0,0 +1,3 @@
+{
+    "X-KDE-PluginInfo-Name": "Oxygen"
+}

clients/oxygen/config/oxygenconfig.cpp

@@ -44,7 +44,9 @@
 
 //_______________________________________________________________________
 
-K_PLUGIN_FACTORY(OxygenConfigPlugin, registerPlugin<Oxygen::Config>(QString(), &Oxygen::Config::create); )
+K_PLUGIN_FACTORY_WITH_JSON(OxygenConfigPlugin,
+                           "config.json",
+                           registerPlugin<Oxygen::Config>(QString(), &Oxygen::Config::create); )
 
 namespace Oxygen
 {

clients/oxygen/oxygenclient.desktop

@@ -169,8 +169,6 @@ Comment[x-test]=xxStyling of the next generation desktopxx
 Comment[zh_CN]=下一代桌面的风格
 Comment[zh_TW]=下一代桌面的樣式
 
-X-KDE-Library=kwin3_oxygen
-
 X-KDE-PluginInfo-Author=Nuno Pinheiro, Casper Boemann, Riccardo Iaconelli, Huynh Huu Long, Thomas Luebking, Hugo Pereira Da Costa, Matthew Woehlke
 X-KDE-PluginInfo-Email=nuno@oxygen-icons.org, cbr@boemann.dk, riccardo@kde.org, long.upcase@googlemail.com, thomas.luebking@web.de, hugo.pereira@free.fr, mw_triad@users.sourceforge.net
 X-KDE-PluginInfo-Name=Oxygen

clients/oxygen/oxygenfactory.cpp

@@ -33,7 +33,7 @@
 #include <KWindowInfo>
 #include <kdeversion.h>
 
-KWIN_DECORATION(OxygenPluginFactory, Oxygen::Factory)
+KWIN_DECORATION(OxygenPluginFactory, "oxygenclient.json", Oxygen::Factory)
 
 namespace Oxygen
 {

decorations.cpp

@@ -39,9 +39,9 @@ DecorationPlugin::DecorationPlugin(QObject *parent)
     , KDecorationPlugins(KSharedConfig::openConfig())
     , m_disabled(false)
 {
-    defaultPlugin = QStringLiteral("kwin3_oxygen");
+    defaultPlugin = QStringLiteral("Oxygen");
 #ifndef KWIN_BUILD_OXYGEN
-    defaultPlugin = QStringLiteral("kwin3_aurorae");
+    defaultPlugin = QStringLiteral("aurorae");
 #endif
 #ifdef KWIN_BUILD_DECORATIONS
     loadPlugin(QString());   // load the plugin specified in cfg file

kcmkwin/kwindecoration/configdialog.cpp

@@ -25,8 +25,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <KSharedConfig>
 #include <KLocalizedString>
 #include <KConfigGroup>
-#include <KPluginFactory>
+#include <KPluginTrader>
-#include <KPluginLoader>
 #include <QDialogButtonBox>
 #include <QPushButton>
 
@@ -89,25 +88,24 @@ KWinDecorationConfigDialog::KWinDecorationConfigDialog(QString deco, const QList
     connect(m_buttons, SIGNAL(accepted()), SLOT(accept()));
     connect(m_buttons, SIGNAL(rejected()), SLOT(reject()));
 
-    KPluginLoader loader(styleToConfigLib(deco));
+    m_pluginConfigWidget = new QWidget(this);
-    KPluginFactory *factory = loader.factory();
+    m_pluginConfigWidget->setLayout(new QVBoxLayout);
-    if (factory) {
+    m_pluginObject = KPluginTrader::self()->createInstanceFromQuery<QObject>(QStringLiteral("kf5/kwin/kdecorations/config"),
-        m_pluginConfigWidget = new QWidget(this);
+                                                                              QString(),
-        m_pluginConfigWidget->setLayout(new QVBoxLayout);
+                                                                              QStringLiteral("[X-KDE-PluginInfo-Name] == '%1'").arg(deco),
-        m_pluginObject = factory->create<QObject>(m_pluginConfigWidget, m_pluginConfigWidget, QString(),
+                                                                              m_pluginConfigWidget,
-                                                  QVariantList() << QStringLiteral("kwinrc") << QStringLiteral("Style"));
+                                                                              m_pluginConfigWidget,
-
+                                                                              QVariantList() << QStringLiteral("kwinrc") << QStringLiteral("Style"));
+    if (m_pluginObject) {
         // connect required signals and slots together...
         connect(this, SIGNAL(accepted()), this, SLOT(slotAccepted()));
         connect(m_pluginObject, SIGNAL(changed()), this, SLOT(slotSelectionChanged()));
         connect(this, SIGNAL(pluginSave(KConfigGroup&)), m_pluginObject, SLOT(save(KConfigGroup&)));
         connect(m_buttons->button(QDialogButtonBox::RestoreDefaults), SIGNAL(clicked(bool)), m_pluginObject, SLOT(defaults()));
         connect(m_buttons->button(QDialogButtonBox::RestoreDefaults), SIGNAL(clicked(bool)), SLOT(slotDefault()));
-    }
-
-    if (m_pluginConfigWidget) {
         layout->addWidget(m_pluginConfigWidget);
     }
+
     layout->addWidget(m_buttons);
 
     if (borderSizes.count() >= 2) {
@@ -160,14 +158,6 @@ void KWinDecorationConfigDialog::slotSelectionChanged()
     m_buttons->button(QDialogButtonBox::Reset)->setEnabled(true);
 }
 
-QString KWinDecorationConfigDialog::styleToConfigLib(const QString& styleLib) const
-{
-    if (styleLib.startsWith(QLatin1String("kwin3_")))
-        return "kwin_" + styleLib.mid(6) + "_config";
-    else
-        return styleLib + "_config";
-}
-
 void KWinDecorationConfigDialog::slotDefault()
 {
     if (m_borderSizes.count() >= 2)

kcmkwin/kwindecoration/configdialog.h

@@ -70,7 +70,6 @@ private Q_SLOTS:
 
 private:
     int borderSizeToIndex(KDecorationDefines::BorderSize size, const QList<QVariant>& sizes);
-    QString styleToConfigLib(const QString& styleLib) const;
 
 private:
     KWinDecorationConfigForm* m_ui;

kcmkwin/kwindecoration/decorationmodel.cpp

@@ -33,6 +33,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <KDE/KLocalizedString>
 #include <KServiceTypeTrader>
 #include <KPluginInfo>
+#include <KPluginTrader>
 #include "kwindecoration.h"
 
 /* WARNING -------------------------------------------------------------------------
@@ -47,6 +48,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 * (which is invoked on deco deconstruction)
 * WARNING ------------------------------------------------------------------------ */
 
+static const QString s_auroraePluginName = QStringLiteral("aurorae");
+
 namespace KWin
 {
 
@@ -87,41 +90,33 @@ void DecorationModel::reload()
 void DecorationModel::findDecorations()
 {
     beginResetModel();
-    const QStringList dirList = QStandardPaths::locateAll(QStandardPaths::GenericDataLocation, "kwin", QStandardPaths::LocateDirectory);
+    const auto decorations = KPluginTrader::self()->query(QStringLiteral("kf5/kwin/kdecorations"));
-
+    for (const KPluginInfo &plugin : decorations) {
-    foreach (const QString & dir, dirList) {
+        if (plugin.pluginName() == s_auroraePluginName) {
-        QDir d(dir);
+            // read the Aurorae themes
-        if (d.exists()) {
+            findAuroraeThemes();
-            foreach (const QFileInfo & fi, d.entryInfoList()) {
+            continue;
-                const QString filename(fi.absoluteFilePath());
-                if (KDesktopFile::isDesktopFile(filename)) {
-                    const KDesktopFile desktopFile(filename);
-                    const QString libName = desktopFile.desktopGroup().readEntry("X-KDE-Library");
-
-                    if (!libName.isEmpty() && libName.startsWith(QLatin1String("kwin3_"))) {
-                        if (libName == "kwin3_aurorae") {
-                            // read the Aurorae themes
-                            findAuroraeThemes();
-                            continue;
-                        }
-                        DecorationModelData data;
-                        data.name = desktopFile.readName();
-                        data.libraryName = libName;
-                        data.type = DecorationModelData::NativeDecoration;
-                        data.borderSize = KDecorationDefines::BorderNormal;
-                        data.closeDblClick = false;
-                        metaData(data, desktopFile);
-                        m_decorations.append(data);
-                    }
-                }
-            }
         }
+        DecorationModelData data;
+        data.name = plugin.name();
+        data.pluginName = plugin.pluginName();
+        data.type = DecorationModelData::NativeDecoration;
+        data.borderSize = KDecorationDefines::BorderNormal;
+        data.closeDblClick = false;
+        data.comment = plugin.comment();
+        data.author = plugin.author();
+        data.email = plugin.email();
+        data.version = plugin.version();
+        data.license = plugin.license();
+        data.website = plugin.website();
+        m_decorations.append(data);
     }
+
     KService::List offers = KServiceTypeTrader::self()->query("KWin/Decoration");
     foreach (KService::Ptr service, offers) {
         DecorationModelData data;
         data.name = service->name();
-        data.libraryName = "kwin3_aurorae";
+        data.pluginName = s_auroraePluginName;
         data.type = DecorationModelData::QmlDecoration;
         data.auroraeName = service->property("X-KDE-PluginInfo-Name").toString();
         QString scriptName = service->property("X-Plasma-MainScript").toString();
@@ -178,7 +173,7 @@ void DecorationModel::findAuroraeThemes()
 
         DecorationModelData data;
         data.name = name;
-        data.libraryName = "kwin3_aurorae";
+        data.pluginName = s_auroraePluginName;
         data.type = DecorationModelData::AuroraeDecoration;
         data.auroraeName = packageName;
         KConfigGroup config(m_config, data.auroraeName);
@@ -216,7 +211,7 @@ QVariant DecorationModel::data(const QModelIndex& index, int role) const
     case NameRole:
         return m_decorations[ index.row()].name;
     case LibraryNameRole:
-        return m_decorations[ index.row()].libraryName;
+        return m_decorations[ index.row()].pluginName;
     case TypeRole:
         return m_decorations[ index.row()].type;
     case AuroraeNameRole:
@@ -238,7 +233,7 @@ QVariant DecorationModel::data(const QModelIndex& index, int role) const
     case BorderSizesRole: {
         QList< QVariant > sizes;
         const bool mustDisablePreview = m_plugins->factory() && m_plugins->factory() == m_preview->factory();
-        if (m_plugins->loadPlugin(m_decorations[index.row()].libraryName) && m_plugins->factory()) {
+        if (m_plugins->loadPlugin(m_decorations[index.row()].pluginName) && m_plugins->factory()) {
             foreach (KDecorationDefines::BorderSize size, m_plugins->factory()->borderSizes())   // krazy:exclude=foreach
                 sizes << int(size);
             if (mustDisablePreview) // it's nuked with destroyPreviousPlugin()
@@ -321,7 +316,7 @@ void DecorationModel::setButtons(bool custom, const QList<KDecorationDefines::De
 QModelIndex DecorationModel::indexOfLibrary(const QString& libraryName) const
 {
     for (int i = 0; i < m_decorations.count(); i++) {
-        if (m_decorations.at(i).libraryName.compare(libraryName) == 0)
+        if (m_decorations.at(i).pluginName.compare(libraryName) == 0)
             return index(i);
     }
     return QModelIndex();

kcmkwin/kwindecoration/decorationmodel.h

@@ -45,7 +45,7 @@ public:
         QmlDecoration = 2
     };
     QString name;
-    QString libraryName;
+    QString pluginName;
     DecorationType type;
     QString comment;
     QString author;

kcmkwin/kwindecoration/kwindecoration.cpp

@@ -62,6 +62,8 @@ K_PLUGIN_FACTORY(KWinDecoFactory,
 namespace KWin
 {
 
+static const QString s_defaultPluginName = QStringLiteral("Oxygen");
+
 KWinDecorationForm::KWinDecorationForm(QWidget* parent)
     : QWidget(parent)
 {
@@ -183,18 +185,18 @@ void KWinDecorationModule::readConfig(const KConfigGroup & conf)
     // Find the corresponding decoration name to that of
     // the current plugin library name
 
-    QString libraryName = conf.readEntry("PluginLib", "kwin3_oxygen");
+    QString libraryName = conf.readEntry("PluginLib", s_defaultPluginName);
 
     if (libraryName.isEmpty()) {
         // Selected decoration doesn't exist, use the default
-        libraryName = "kwin3_oxygen";
+        libraryName = s_defaultPluginName;
     }
 
     const int bsize = conf.readEntry("BorderSize", (int)BorderNormal);
     BorderSize borderSize = BorderNormal;
     if (bsize >= BorderTiny && bsize < BordersCount)
         borderSize = static_cast< BorderSize >(bsize);
-    if (libraryName == "kwin3_aurorae") {
+    if (libraryName == "aurorae") {
         KConfig auroraeConfig("auroraerc");
         KConfigGroup group(&auroraeConfig, "Engine");
         const QString themeName = group.readEntry("ThemeName", "example-deco");

libkdecorations/kdecoration.h

@@ -43,13 +43,17 @@ DEALINGS IN THE SOFTWARE.
  * The KPluginFactory sub class returns a new instance of the specified KDecorationFactory.
  *
  * @param pluginfactoryname The name to be used for the KPluginFactory, passed to K_PLUGIN_FACTORY
+ * @param jsonFile Name of the json file to be compiled into the decoration plugin as metadata
  * @param classname The class name of the KDecorationFactory subclass
  *
  * Example:
  * @code
- * KWIN_DECORATION(MyDecoPluginFactory, MyDeco::Factory)
+ * KWIN_DECORATION(MyDecoPluginFactory, "mydeco.json", MyDeco::Factory)
  * @endcode
  *
+ * Please refer to the documentation of K_PLUGIN_FACTORY_WITH_JSON in KF5::Service for how to
+ * create and use the json file.
+ *
  * In case the decoration plugin wants to have more control over the created factory (e.g. a singleton)
  * it is recommended to not use this convenience macro, but specify an own K_PLUGIN_FACTORY. In that
  * case it is also required to add
@@ -59,9 +63,9 @@ DEALINGS IN THE SOFTWARE.
  *
  * to add the correct plugin version. This is also handled by this macro in the default case.
  **/
-#define KWIN_DECORATION( pluginfactoryname, classname ) \
+#define KWIN_DECORATION( pluginfactoryname, json, classname ) \
     QObject *createDecorationFactory(QWidget *, QObject *, const QList<QVariant> &) { return new classname(); } \
-    K_PLUGIN_FACTORY(pluginfactoryname, registerPlugin<classname>(QString(), &createDecorationFactory);) \
+    K_PLUGIN_FACTORY_WITH_JSON(pluginfactoryname, json, registerPlugin<classname>(QString(), &createDecorationFactory);) \
     K_EXPORT_PLUGIN_VERSION(KWIN_DECORATION_API_VERSION)
 
 #define KWIN_DECORATION_BRIDGE_API_VERSION 1

libkdecorations/kdecoration_plugins_p.cpp

@@ -31,6 +31,7 @@ DEALINGS IN THE SOFTWARE.
 #include <klibrary.h>
 #include <KPluginFactory>
 #include <KPluginLoader>
+#include <KPluginTrader>
 #include <kconfiggroup.h>
 #include <KDE/KLocalizedString>
 #include <assert.h>
@@ -44,7 +45,7 @@ DEALINGS IN THE SOFTWARE.
 KDecorationPlugins::KDecorationPlugins(const KSharedConfigPtr &cfg)
     :   fact(nullptr),
         old_fact(nullptr),
-        pluginStr(QStringLiteral("kwin3_undefined ")),
+        pluginStr(QStringLiteral("undefined ")),
         config(cfg)
 {
 }
@@ -105,7 +106,13 @@ bool KDecorationPlugins::loadPlugin(QString nameStr)
 
     auto createFactory = [](const QString &pluginName) -> KDecorationFactory* {
         qDebug() << "Trying to load decoration plugin" << pluginName;
-        KPluginLoader loader(pluginName);
+        const QString query = QStringLiteral("[X-KDE-PluginInfo-Name] == '%1'").arg(pluginName);
+        const auto offers = KPluginTrader::self()->query(QStringLiteral("kf5/kwin/kdecorations"), QString(), query);
+        if (offers.isEmpty()) {
+            qDebug() << "Decoration plugin not found";
+            return nullptr;
+        }
+        KPluginLoader loader(offers.first().libraryPath());
         if (loader.pluginVersion() != KWIN_DECORATION_API_VERSION) {
             qWarning() << i18n("The library %1 has wrong API version %2", loader.pluginName(), loader.pluginVersion());
             return nullptr;