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/****************************************************************************
**
** 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 Qt3D module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** GNU Lesser General Public License Usage
** 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.
**
** 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.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qdownloadmanager.h"
#include <QNetworkAccessManager>
#include <QNetworkReply>
#include <QNetworkRequest>
#include <QDebug>
QT_BEGIN_NAMESPACE
/*!
\class QDownloadManager
\brief The QDownloadManager class provides asset data download capability within the
current thread.
\since 4.8
\ingroup qt3d
\ingroup qt3d::network
QDownloadManager extends the QAbstractDownloadManager class for use in a
single-threaded Qt3D application. The QDownloadManager performs its network
activities asynchronously, and processing will continue as normal while the download
is underway (ie. the call is non-blocking).
It should be noted that this does not preclude its usage in a multi-threaded
application, rather that it does not itself spawn any threads of its own.
In circumstances where an application will benefit greatly from multithreading,
the developer may prefer to use the QThreadedDownloadManager.
At the core of QDownloadManager is a QNetworkAccessManager which is
shared by all instances of QDownloadManager. The download manager itself
provides all handling of network requests and replies internally, and
allows for redirection of URLs and handling of errors without the need
for the user to query network replies.
To use the QDownloadManager simply create an instance of the class
within your code, and connect QDownloadManager's downloadComplete() signal
to a slot in your own code, then call the downloadAsset() function.
For example
\code
QDownloadManager dlmanage;
connect(this, SLOT(myReceiverSlot(QByteArray)), &dlmanage, SIGNAL(downloadComplete(QByteArray)));
if (!dlmanage.downloadAsset(QUrl("www.my.image.url.net/image.jpg"))) {
dWarning("the manager was unable to send the url request.");
}
\endcode
The QDownloadManager will emit the downloadComplete() signal which contains
all of the downloaded data in a QByteArray. It is the user's responsibility
to convert this data to the format they require, and to verify that it is
correct.
*/
Q_GLOBAL_STATIC(QNetworkAccessManager, getNetworkAccessManager)
/*!
Constructs a new instance of the QDownloadManager and attach it
to a \a parent QObject. Internally this initialises the
QNetworkAccessManager instance which is shared by all instances of
this class, and manages downloading of asset data.
*/
QDownloadManager::QDownloadManager(QObject *parent) : QAbstractDownloadManager(parent)
{
}
/*!
Destroys the current instance of the QDownloadManager. The destructor
checks whether other instances of the class exist, and if none are found
it deletes the internal QNetworkAccessManager instance.
*/
QDownloadManager::~QDownloadManager()
{
}
/*!
Instructs the QDownloadManager to download the content specified
in \a assetUrl. This may be a texture, 3d model, or similar.
A return value of true indicates that the network request was
successfully queued for sending, while a return value of false
indicates a problem with sending (possibly a poorly specified URL, or
network failure).
*/
bool QDownloadManager::beginDownload(QUrl assetUrl)
{
//URL Sanity check
if ( ! assetUrl.isValid()) {
qWarning() << "Invalid texture URL: " << assetUrl.toString();
return false;
}
QNetworkRequest request(assetUrl);
request.setAttribute(QNetworkRequest::CacheLoadControlAttribute, QNetworkRequest::PreferCache);
QNetworkReply *netReply = getNetworkAccessManager()->get(request);
if (!netReply) {
qWarning() << "Unable to send the request to the network.";
return false;
}
connect(netReply, SIGNAL(finished()), this, SLOT(netReplyDone()));
return true;
}
/*!
\internal
Internally used slot which is invoked when a download is finished.
This handles redirection of URLs internally, as well as error checking.
A successful download will emit the downloadComplete() signal which
the user is responsible for handling in their own application.
\sa downloadComplete()
*/
void QDownloadManager::netReplyDone()
{
//Ensure sanity of the sender
QNetworkReply *reply = qobject_cast<QNetworkReply*>(sender());
if (!reply) {
qWarning("DownloadManager's signal sender was not a QNetworkReply.");
return;
}
if (reply->error() != QNetworkReply::NoError) {
qWarning() << "Error in network reply: " << reply->url() << "(" << reply->errorString() << ")";
reply->deleteLater();
QByteArray tempArray;
tempArray.clear();
emit downloadComplete(tempArray);
return;
}
//In the case of a reply which is a redirect
QVariant redirection = reply->attribute(QNetworkRequest::RedirectionTargetAttribute);
if (redirection.isValid()) {
QUrl url = redirection.toUrl();
//Check if we have a relative URL
if (url.isRelative()) {
url.setScheme(reply->url().scheme());
url.setEncodedHost(reply->url().encodedHost());
}
//Reissue redirected request.
QNetworkRequest request(url);
if (getNetworkAccessManager())
{
QNetworkReply * netReply = getNetworkAccessManager()->get(request);
connect(netReply, SIGNAL(finished()), SLOT(netReplyDone()));
reply->deleteLater();
} else {
QByteArray tempArray;
tempArray.clear();
emit downloadComplete(tempArray);
}
return;
}
//In the case of just data being returned
//qDebug() << "ContentType:" << reply->header(QNetworkRequest::ContentTypeHeader).toString();
QByteArray assetData;
assetData = reply->readAll();
reply->deleteLater();
emit downloadComplete(assetData);
}
QT_END_NAMESPACE
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