[scripting] Make DBus invokable run method return result after execution

Summary:
In 403038 the user expected the DBus call to run to finish before
processing the next request. For a singleshot script that makes a lot of
sense, otherwise you have no idea when it finishes.

This also allows us to return errors.

CCBUG: 403038

Test Plan:
NUM=$(qdbus org.kde.KWin /Scripting org.kde.kwin.Scripting.loadScript /noFile.js Minimize)
qdbus org.kde.KWin /$NUM org.kde.kwin.Scripting.run
  Error: org.kde.kwin.Scripting.FileError
  Could not open /noFile.js

Running a real script behaved effectively the same as before.

Reviewers: #kwin, graesslin

Reviewed By: #kwin, graesslin

Subscribers: zzag, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D18127

autotests/CMakeLists.txt

@@ -365,6 +365,7 @@ target_link_libraries(testOnScreenNotification
     Qt5::Test
     Qt5::Widgets # QAction include
     Qt5::Quick
+    Qt5::DBus
     KF5::ConfigCore
 )
 

autotests/tabbox/CMakeLists.txt

@@ -22,6 +22,7 @@ target_link_libraries( testTabBoxClientModel
     Qt5::Script
     Qt5::Quick
     Qt5::Test
+    Qt5::DBus
     Qt5::X11Extras
     KF5::ConfigCore
     KF5::I18n
@@ -54,6 +55,7 @@ target_link_libraries( testTabBoxHandler
     Qt5::Script
     Qt5::Quick
     Qt5::Test
+    Qt5::DBus
     Qt5::X11Extras
     KF5::ConfigCore
     KF5::I18n

scripting/scripting.cpp

@@ -465,6 +465,12 @@ void KWin::Script::run()
     if (running() || m_starting) {
         return;
     }
+
+    if (calledFromDBus()) {
+        m_invocationContext = message();
+        setDelayedReply(true);
+    }
+
     m_starting = true;
     QFutureWatcher<QByteArray> *watcher = new QFutureWatcher<QByteArray>(this);
     connect(watcher, SIGNAL(finished()), SLOT(slotScriptLoadedFromFile()));
@@ -492,8 +498,16 @@ void KWin::Script::slotScriptLoadedFromFile()
         // do not load empty script
         deleteLater();
         watcher->deleteLater();
+
+        if (m_invocationContext.type() == QDBusMessage::MethodCallMessage) {
+            auto reply = m_invocationContext.createErrorReply("org.kde.kwin.Scripting.FileError", QString("Could not open %1").arg(fileName()));
+            QDBusConnection::sessionBus().send(reply);
+            m_invocationContext = QDBusMessage();
+        }
+
         return;
     }
+
     QScriptValue optionsValue = m_engine->newQObject(options, QScriptEngine::QtOwnership,
                             QScriptEngine::ExcludeSuperClassContents | QScriptEngine::ExcludeDeleteLater);
     m_engine->globalObject().setProperty(QStringLiteral("options"), optionsValue, QScriptValue::Undeletable);
@@ -509,6 +523,12 @@ void KWin::Script::slotScriptLoadedFromFile()
         deleteLater();
     }
 
+    if (m_invocationContext.type() == QDBusMessage::MethodCallMessage) {
+        auto reply = m_invocationContext.createReply();
+        QDBusConnection::sessionBus().send(reply);
+        m_invocationContext = QDBusMessage();
+    }
+
     watcher->deleteLater();
     setRunning(true);
     m_starting = false;

scripting/scripting.h

@@ -30,6 +30,9 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <QtScript/QScriptEngineAgent>
 #include <QJSValue>
 
+#include <QDBusContext>
+#include <QDBusMessage>
+
 class QQmlComponent;
 class QQmlContext;
 class QQmlEngine;
@@ -214,7 +217,7 @@ private:
     QList<QScriptValue> m_userActionsMenuCallbacks;
 };
 
-class Script : public AbstractScript
+class Script : public AbstractScript, QDBusContext
 {
     Q_OBJECT
     Q_CLASSINFO("D-Bus Interface", "org.kde.kwin.Scripting")
@@ -254,6 +257,7 @@ private:
      **/
     QByteArray loadScriptFromFile(const QString &fileName);
     QScriptEngine *m_engine;
+    QDBusMessage m_invocationContext;
     bool m_starting;
     QScopedPointer<ScriptUnloaderAgent> m_agent;
     QHash<int, QAction*> m_touchScreenEdgeCallbacks;