Moved the QML Observer Service and related functionality into Qt

This code was previously developed as part of Qt Creator in
share/qtcreator/qml/qmljsdebugger/

Moving it into Qt will allow us to simplify the setup required before
you can debug QML applications.

To avoid adding too much weight to the QtDeclarative module, a
declarativeobserver plugin was introduced that contains the
QDeclarativeViewObserver and related classes. The
QDeclarativeObserverService is just a stub service that loads this
plugin once a QML debugging client connects. The plugin implements the
QDeclarativeObserverInterface

A QJSDebugService was separated out of QJSDebuggerAgent, so
that the service can be active while the agent is instantiated lazily.
Each QDeclarativeEngine adds itself to the QJSDebugService. Currently
only the first one is used when instantiating the agent.

QDeclarativeObserverService is hooked into QDeclarativeView, with the
view registering itself to the service, allowing the
QDeclarativeViewObserver to be created for the view once somebody
connects to the service. Again, only the first view is used at the
moment.

Change-Id: Ib50579c6d24361c2b39528e5556410d3446c2e90
Reviewed-by: Martin Jones
Reviewed-by: Michael Brasser

1 files changed, 198 insertions, 0 deletions

diff --git a/src/declarative/debugger/qjsdebugservice.cpp b/src/declarative/debugger/qjsdebugservice.cpp
new file mode 100644
index 0000000..f8cd095
--- /dev/null
+++ b/src/declarative/debugger/qjsdebugservice.cpp
@@ -0,0 +1,198 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtDeclarative module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** 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, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "private/qjsdebugservice_p.h"
+#include "private/qjsdebuggeragent_p.h"
+
+#include <QtCore/qdatastream.h>
+#include <QtCore/qdebug.h>
+#include <QtCore/qstringlist.h>
+#include <QtDeclarative/qdeclarativeengine.h>
+
+Q_GLOBAL_STATIC(QJSDebugService, serviceInstance)
+
+QJSDebugService::QJSDebugService(QObject *parent)
+    : QDeclarativeDebugService(QLatin1String("JSDebugger"), parent)
+    , m_agent(0)
+{
+}
+
+QJSDebugService::~QJSDebugService()
+{
+    delete m_agent;
+}
+
+QJSDebugService *QJSDebugService::instance()
+{
+    return serviceInstance();
+}
+
+void QJSDebugService::addEngine(QDeclarativeEngine *engine)
+{
+    Q_ASSERT(engine);
+    Q_ASSERT(!m_engines.contains(engine));
+
+    m_engines.append(engine);
+}
+
+void QJSDebugService::removeEngine(QDeclarativeEngine *engine)
+{
+    Q_ASSERT(engine);
+    Q_ASSERT(m_engines.contains(engine));
+
+    m_engines.removeAll(engine);
+}
+
+void QJSDebugService::statusChanged(Status status)
+{
+    if (status == Enabled && !m_engines.isEmpty() && !m_agent) {
+        // Multiple engines are currently unsupported
+        QDeclarativeEngine *engine = m_engines.first();
+        m_agent = new QJSDebuggerAgent(engine, engine);
+
+        connect(m_agent, SIGNAL(stopped(bool,QString)),
+                this, SLOT(executionStopped(bool,QString)));
+
+    } else if (status != Enabled && m_agent) {
+        delete m_agent;
+        m_agent = 0;
+    }
+}
+
+void QJSDebugService::messageReceived(const QByteArray &message)
+{
+    if (!m_agent) {
+        qWarning() << "QJSDebugService::messageReceived: No QJSDebuggerAgent available";
+        return;
+    }
+
+    QDataStream ds(message);
+    QByteArray command;
+    ds >> command;
+    if (command == "BREAKPOINTS") {
+        JSAgentBreakpoints breakpoints;
+        ds >> breakpoints;
+        m_agent->setBreakpoints(breakpoints);
+
+        //qDebug() << "BREAKPOINTS";
+        //foreach (const JSAgentBreakpointData &bp, breakpoints)
+        //    qDebug() << "BREAKPOINT: " << bp.fileUrl << bp.lineNumber;
+    } else if (command == "WATCH_EXPRESSIONS") {
+        QStringList watchExpressions;
+        ds >> watchExpressions;
+        m_agent->setWatchExpressions(watchExpressions);
+    } else if (command == "STEPOVER") {
+        m_agent->stepOver();
+    } else if (command == "STEPINTO" || command == "INTERRUPT") {
+        m_agent->stepInto();
+    } else if (command == "STEPOUT") {
+        m_agent->stepOut();
+    } else if (command == "CONTINUE") {
+        m_agent->continueExecution();
+    } else if (command == "EXEC") {
+        QByteArray id;
+        QString expr;
+        ds >> id >> expr;
+
+        JSAgentWatchData data = m_agent->executeExpression(expr);
+
+        QByteArray reply;
+        QDataStream rs(&reply, QIODevice::WriteOnly);
+        rs << QByteArray("RESULT") << id << data;
+        sendMessage(reply);
+    } else if (command == "EXPAND") {
+        QByteArray requestId;
+        quint64 objectId;
+        ds >> requestId >> objectId;
+
+        QList<JSAgentWatchData> result = m_agent->expandObjectById(objectId);
+
+        QByteArray reply;
+        QDataStream rs(&reply, QIODevice::WriteOnly);
+        rs << QByteArray("EXPANDED") << requestId << result;
+        sendMessage(reply);
+    } else if (command == "ACTIVATE_FRAME") {
+        int frameId;
+        ds >> frameId;
+
+        QList<JSAgentWatchData> locals = m_agent->localsAtFrame(frameId);
+
+        QByteArray reply;
+        QDataStream rs(&reply, QIODevice::WriteOnly);
+        rs << QByteArray("LOCALS") << frameId << locals;
+        sendMessage(reply);
+    } else if (command == "SET_PROPERTY") {
+        QByteArray id;
+        qint64 objectId;
+        QString property;
+        QString value;
+        ds >> id >> objectId >> property >> value;
+
+        m_agent->setProperty(objectId, property, value);
+
+        //TODO: feedback
+    } else if (command == "PING") {
+        int ping;
+        ds >> ping;
+        QByteArray reply;
+        QDataStream rs(&reply, QIODevice::WriteOnly);
+        rs << QByteArray("PONG") << ping;
+        sendMessage(reply);
+    } else {
+        qDebug() << Q_FUNC_INFO << "Unknown command" << command;
+    }
+
+    QDeclarativeDebugService::messageReceived(message);
+}
+
+void QJSDebugService::executionStopped(bool becauseOfException,
+                                       const QString &exception)
+{
+    const QList<JSAgentStackData> backtrace = m_agent->backtrace();
+    const QList<JSAgentWatchData> watches = m_agent->watches();
+    const QList<JSAgentWatchData> locals = m_agent->locals();
+
+    QByteArray reply;
+    QDataStream rs(&reply, QIODevice::WriteOnly);
+    rs << QByteArray("STOPPED") << backtrace << watches << locals
+       << becauseOfException << exception;
+    sendMessage(reply);
+}