plasma-framework/dataengine.cpp

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/*
* Copyright 2006-2007 Aaron Seigo <aseigo@kde.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Library General Public License as
* published by the Free Software Foundation; either version 2, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details
*
* You should have received a copy of the GNU Library General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include "dataengine.h"
#include "private/dataengine_p.h"
#include <QQueue>
#include <QTimer>
#include <QTime>
#include <QTimerEvent>
#include <QVariant>
#include <kdebug.h>
#include <kplugininfo.h>
#include <kservice.h>
#include <kstandarddirs.h>
#include "authorizationmanager.h"
#include "datacontainer.h"
#include "package.h"
#include "service.h"
#include "scripting/dataenginescript.h"
#include "private/authorizationmanager_p.h"
#include "private/dataengineservice.h"
#include "private/service_p.h"
namespace Plasma
{
DataEngine::DataEngine(QObject *parent, KService::Ptr service)
: QObject(parent),
d(new DataEnginePrivate(this, service))
{
}
DataEngine::DataEngine(QObject *parent, const QVariantList &args)
: QObject(parent),
d(new DataEnginePrivate(this, KService::serviceByStorageId(args.count() > 0 ? args[0].toString() : QString())))
{
}
DataEngine::~DataEngine()
{
//kDebug() << objectName() << ": bye bye birdy! ";
delete d;
}
QStringList DataEngine::sources() const
{
if (d->script) {
return d->script->sources();
} else {
return d->sources.keys();
}
}
Service *DataEngine::serviceForSource(const QString &source)
{
if (d->script) {
return d->script->serviceForSource(source);
} else {
return new NullService(source, this);
}
}
void DataEngine::connectSource(const QString &source, QObject *visualization,
uint pollingInterval,
Plasma::IntervalAlignment intervalAlignment) const
{
//kDebug() << "connectSource" << source;
bool newSource;
DataContainer *s = d->requestSource(source, &newSource);
if (s) {
// we suppress the immediate invocation of dataUpdated here if the
// source was prexisting and they don't request delayed updates
// (we want to do an immediate update in that case so they don't
// have to wait for the first time out)
d->connectSource(s, visualization, pollingInterval, intervalAlignment,
!newSource || pollingInterval > 0);
//kDebug() << " ==> source connected";
}
}
void DataEngine::connectAllSources(QObject *visualization, uint pollingInterval,
Plasma::IntervalAlignment intervalAlignment) const
{
foreach (DataContainer *s, d->sources) {
d->connectSource(s, visualization, pollingInterval, intervalAlignment);
}
}
void DataEngine::disconnectSource(const QString &source, QObject *visualization) const
{
DataContainer *s = d->source(source, false);
if (s) {
s->disconnectVisualization(visualization);
}
}
DataContainer *DataEngine::containerForSource(const QString &source)
{
return d->source(source, false);
}
DataEngine::Data DataEngine::query(const QString &source) const
{
bool newSource;
DataContainer *s = d->requestSource(source, &newSource);
if (!s) {
return DataEngine::Data();
} else if (!newSource && d->minPollingInterval >= 0 &&
s->timeSinceLastUpdate() >= uint(d->minPollingInterval)) {
DataEngine *unconstThis = const_cast<DataEngine*>(this);
if (unconstThis->updateSourceEvent(source)) {
unconstThis->scheduleSourcesUpdated();
}
}
DataEngine::Data data = s->data();
s->checkUsage();
return data;
}
void DataEngine::init()
{
if (d->script) {
d->script->init();
} else {
// kDebug() << "called";
// default implementation does nothing. this is for engines that have to
// start things in motion external to themselves before they can work
}
}
bool DataEngine::sourceRequestEvent(const QString &name)
{
if (d->script) {
return d->script->sourceRequestEvent(name);
} else {
return false;
}
}
bool DataEngine::updateSourceEvent(const QString &source)
{
if (d->script) {
return d->script->updateSourceEvent(source);
} else {
//kDebug() << source;
return false; //TODO: should this be true to trigger, even needless, updates on every tick?
}
}
void DataEngine::setData(const QString &source, const QVariant &value)
{
setData(source, source, value);
}
void DataEngine::setData(const QString &source, const QString &key, const QVariant &value)
{
DataContainer *s = d->source(source, false);
bool isNew = !s;
if (isNew) {
s = d->source(source);
}
s->setData(key, value);
if (isNew) {
emit sourceAdded(source);
}
scheduleSourcesUpdated();
}
void DataEngine::setData(const QString &source, const Data &data)
{
DataContainer *s = d->source(source, false);
bool isNew = !s;
if (isNew) {
s = d->source(source);
}
Data::const_iterator it = data.constBegin();
while (it != data.constEnd()) {
s->setData(it.key(), it.value());
++it;
}
if (isNew) {
emit sourceAdded(source);
}
scheduleSourcesUpdated();
}
void DataEngine::removeAllData(const QString &source)
{
DataContainer *s = d->source(source, false);
if (s) {
s->removeAllData();
scheduleSourcesUpdated();
}
}
void DataEngine::removeData(const QString &source, const QString &key)
{
DataContainer *s = d->source(source, false);
if (s) {
s->setData(key, QVariant());
scheduleSourcesUpdated();
}
}
void DataEngine::addSource(DataContainer *source)
{
if (d->sources.contains(source->objectName())) {
kDebug() << "source named \"" << source->objectName() << "\" already exists.";
return;
}
QObject::connect(source, SIGNAL(updateRequested(DataContainer*)),
this, SLOT(internalUpdateSource(DataContainer*)));
d->sources.insert(source->objectName(), source);
emit sourceAdded(source->objectName());
scheduleSourcesUpdated();
}
void DataEngine::setMaxSourceCount(uint limit)
{
if (d->limit == limit) {
return;
}
d->limit = limit;
if (d->limit > 0) {
d->trimQueue();
} else {
d->sourceQueue.clear();
}
}
uint DataEngine::maxSourceCount() const
{
return d->limit;
}
void DataEngine::setMinimumPollingInterval(int minimumMs)
{
if (minimumMs < 0) {
minimumMs = 0;
}
d->minPollingInterval = minimumMs;
}
int DataEngine::minimumPollingInterval() const
{
return d->minPollingInterval;
}
void DataEngine::setPollingInterval(uint frequency)
{
killTimer(d->updateTimerId);
d->updateTimerId = 0;
if (frequency > 0) {
d->updateTimerId = startTimer(frequency);
}
}
/*
NOTE: This is not implemented to prevent having to store the value internally.
When there is a good use case for needing access to this value, we can
add another member to the Private class and add this method.
void DataEngine::pollingInterval()
{
return d->pollingInterval;
}
*/
void DataEngine::removeSource(const QString &source)
{
//kDebug() << "removing source " << source;
SourceDict::iterator it = d->sources.find(source);
if (it != d->sources.end()) {
DataContainer *s = it.value();
// remove it from the limit queue if we're keeping one
if (d->limit > 0) {
QQueue<DataContainer*>::iterator it = d->sourceQueue.begin();
while (it != d->sourceQueue.end()) {
if (*it == s) {
d->sourceQueue.erase(it);
break;
}
++it;
}
}
s->deleteLater();
d->sources.erase(it);
emit sourceRemoved(source);
}
}
void DataEngine::removeAllSources()
{
QMutableHashIterator<QString, Plasma::DataContainer*> it(d->sources);
while (it.hasNext()) {
it.next();
emit sourceRemoved(it.key());
delete it.value();
it.remove();
}
}
bool DataEngine::isValid() const
{
return d->valid;
}
bool DataEngine::isEmpty() const
{
return d->sources.isEmpty();
}
void DataEngine::setValid(bool valid)
{
d->valid = valid;
}
DataEngine::SourceDict DataEngine::containerDict() const
{
return d->sources;
}
void DataEngine::timerEvent(QTimerEvent *event)
{
//kDebug();
if (event->timerId() == d->updateTimerId) {
// if the freq update is less than 0, don't bother
if (d->minPollingInterval < 0) {
//kDebug() << "uh oh.. no polling allowed!";
return;
}
// minPollingInterval
if (d->updateTimestamp.elapsed() < d->minPollingInterval) {
//kDebug() << "hey now.. slow down!";
return;
}
d->updateTimestamp.restart();
d->updateTimerId = 0;
updateAllSources();
} else if (event->timerId() == d->checkSourcesTimerId) {
killTimer(d->checkSourcesTimerId);
d->checkSourcesTimerId = 0;
QHashIterator<QString, Plasma::DataContainer*> it(d->sources);
while (it.hasNext()) {
it.next();
it.value()->checkForUpdate();
}
} else {
QObject::timerEvent(event);
}
}
void DataEngine::updateAllSources()
{
QHashIterator<QString, Plasma::DataContainer*> it(d->sources);
while (it.hasNext()) {
it.next();
//kDebug() << "updating" << it.key();
updateSourceEvent(it.key());
}
scheduleSourcesUpdated();
}
void DataEngine::forceImmediateUpdateOfAllVisualizations()
{
foreach (DataContainer *source, d->sources) {
source->forceImmediateUpdate();
}
}
void DataEngine::setIcon(const QString &icon)
{
d->icon = icon;
}
QString DataEngine::icon() const
{
return d->icon;
}
QString DataEngine::pluginName() const
{
if (!d->dataEngineDescription.isValid()) {
return QString();
}
return d->dataEngineDescription.pluginName();
}
void DataEnginePrivate::publish(AnnouncementMethods methods, const QString &name)
{
if (!publishedService) {
publishedService = new DataEngineService(q);
}
//QString resourceName =
//i18nc("%1 is the name of a dataengine, %2 the name of the machine that engine is published
//on",
//"%1 dataengine on %2", name(), AuthorizationManager::self()->d->myCredentials.name());
kDebug() << "name: " << name;
publishedService->d->publish(methods, name);
}
void DataEnginePrivate::unpublish(const QString &name)
{
if (publishedService) {
publishedService->d->unpublish();
}
}
bool DataEnginePrivate::isPublished() const
{
if (publishedService) {
return publishedService->d->isPublished();
} else {
return false;
}
}
const Package *DataEngine::package() const
{
return d->package;
}
void DataEngine::scheduleSourcesUpdated()
{
if (d->checkSourcesTimerId) {
return;
}
d->checkSourcesTimerId = startTimer(0);
}
QString DataEngine::name() const
{
return d->engineName;
}
void DataEngine::setName(const QString &name)
{
d->engineName = name;
setObjectName(name);
}
// Private class implementations
DataEnginePrivate::DataEnginePrivate(DataEngine *e, KService::Ptr service)
: q(e),
dataEngineDescription(service),
refCount(-1), // first ref
checkSourcesTimerId(0),
updateTimerId(0),
minPollingInterval(-1),
limit(0),
valid(true),
script(0),
package(0),
publishedService(0)
{
updateTimestamp.start();
if (!service) {
engineName = i18n("Unnamed");
return;
}
engineName = service->name();
if (engineName.isEmpty()) {
engineName = i18n("Unnamed");
}
e->setObjectName(engineName);
icon = service->icon();
if (dataEngineDescription.isValid()) {
QString api = dataEngineDescription.property("X-Plasma-API").toString();
if (!api.isEmpty()) {
const QString path =
KStandardDirs::locate("data",
"plasma/dataengines/" + dataEngineDescription.pluginName() + '/');
PackageStructure::Ptr structure =
Plasma::packageStructure(api, Plasma::DataEngineComponent);
structure->setPath(path);
package = new Package(path, structure);
script = Plasma::loadScriptEngine(api, q);
if (!script) {
kDebug() << "Could not create a" << api << "ScriptEngine for the"
<< dataEngineDescription.name() << "DataEngine.";
delete package;
package = 0;
}
}
}
}
DataEnginePrivate::~DataEnginePrivate()
{
delete script;
script = 0;
delete package;
package = 0;
}
void DataEnginePrivate::internalUpdateSource(DataContainer *source)
{
if (minPollingInterval > 0 &&
source->timeSinceLastUpdate() < (uint)minPollingInterval) {
// skip updating this source; it's been too soon
//kDebug() << "internal update source is delaying" << source->timeSinceLastUpdate() << minPollingInterval;
//but fake an update so that the signalrelay that triggered this gets the data from the
//recent update. this way we don't have to worry about queuing - the relay will send a
//signal immediately and everyone else is undisturbed.
source->setNeedsUpdate();
return;
}
if (q->updateSourceEvent(source->objectName())) {
//kDebug() << "queuing an update";
q->scheduleSourcesUpdated();
}/* else {
kDebug() << "no update";
}*/
}
void DataEnginePrivate::ref()
{
--refCount;
}
void DataEnginePrivate::deref()
{
++refCount;
}
bool DataEnginePrivate::isUsed() const
{
return refCount != 0;
}
DataContainer *DataEnginePrivate::source(const QString &sourceName, bool createWhenMissing)
{
DataEngine::SourceDict::const_iterator it = sources.constFind(sourceName);
if (it != sources.constEnd()) {
DataContainer *s = it.value();
if (limit > 0) {
QQueue<DataContainer*>::iterator it = sourceQueue.begin();
while (it != sourceQueue.end()) {
if (*it == s) {
sourceQueue.erase(it);
break;
}
++it;
}
sourceQueue.enqueue(s);
}
return it.value();
}
if (!createWhenMissing) {
return 0;
}
/*kDebug() << "DataEngine " << q->objectName()
<< ": could not find DataContainer " << sourceName
<< ", creating" << endl;*/
DataContainer *s = new DataContainer(q);
s->setObjectName(sourceName);
sources.insert(sourceName, s);
QObject::connect(s, SIGNAL(updateRequested(DataContainer*)),
q, SLOT(internalUpdateSource(DataContainer*)));
if (limit > 0) {
trimQueue();
sourceQueue.enqueue(s);
}
return s;
}
void DataEnginePrivate::connectSource(DataContainer *s, QObject *visualization,
uint pollingInterval,
Plasma::IntervalAlignment align,
bool immediateCall)
{
//kDebug() << "connect source called" << s->objectName() << "with interval" << pollingInterval;
if (pollingInterval > 0) {
// never more frequently than allowed, never more than 20 times per second
uint min = qMax(50, minPollingInterval); // for qMax below
pollingInterval = qMax(min, pollingInterval);
// align on the 50ms
pollingInterval = pollingInterval - (pollingInterval % 50);
}
if (immediateCall) {
// we don't want to do an immediate call if we are simply
// reconnecting
//kDebug() << "immediate call requested, we have:" << s->visualizationIsConnected(visualization);
immediateCall = !s->data().isEmpty() &&
!s->visualizationIsConnected(visualization);
}
s->connectVisualization(visualization, pollingInterval, align);
if (immediateCall) {
QMetaObject::invokeMethod(visualization, "dataUpdated",
Q_ARG(QString, s->objectName()),
Q_ARG(Plasma::DataEngine::Data, s->data()));
}
}
DataContainer *DataEnginePrivate::requestSource(const QString &sourceName, bool *newSource)
{
if (newSource) {
*newSource = false;
}
//kDebug() << "requesting source " << sourceName;
DataContainer *s = source(sourceName, false);
if (!s) {
// we didn't find a data source, so give the engine an opportunity to make one
/*kDebug() << "DataEngine " << q->objectName()
<< ": could not find DataContainer " << sourceName
<< " will create on request" << endl;*/
if (q->sourceRequestEvent(sourceName)) {
s = source(sourceName, false);
if (s) {
// now we have a source; since it was created on demand, assume
// it should be removed when not used
if (newSource) {
*newSource = true;
}
QObject::connect(s, SIGNAL(becameUnused(QString)), q, SLOT(removeSource(QString)));
}
}
}
return s;
}
void DataEnginePrivate::trimQueue()
{
uint queueCount = sourceQueue.count();
while (queueCount >= limit && !sourceQueue.isEmpty()) {
DataContainer *punted = sourceQueue.dequeue();
q->removeSource(punted->objectName());
queueCount = sourceQueue.count();
}
}
}
#include "dataengine.moc"