WebResourcesProvider: initial implementation allowing to browse and

download online resources just like if they were local files

include/web_resources_provider.h

@@ -25,21 +25,30 @@
 #ifndef _WEB_RESOURCES_PROVIDER_H
 #define _WEB_RESOURCES_PROVIDER_H
 
-#include <QtCore/QByteArray>
+#include <QtCore/QBuffer>
+#include <QtXml/QDomNode>
 
 #include "resources_provider.h"
 #include "resources_item.h"
 
 
+class QHttp;
+
+
 class WebResourcesProvider : public ResourcesProvider
 {
+	Q_OBJECT
 public:
 	WebResourcesProvider( const QString & _url );
-	virtual ~WebResourcesProvider()
+	virtual ~WebResourcesProvider();
+
+	virtual QString providerName( void ) const
 	{
+		return "WebResourcesProvider";
 	}
 
-	virtual ResourcesDB * createResourcesDB( void );
+	virtual void updateDatabase( void );
+
 	virtual int dataSize( const ResourcesItem * _item ) const
 	{
 		// asume that the size we have set before from the web
@@ -50,7 +59,19 @@ public:
 					int _maxSize = -1 ) const;
 
 
+private slots:
+	void finishDownload( int _id, bool );
+
+
 private:
+	void importNodeIntoDB( const QDomNode & n,
+						ResourcesTreeItem * _parent );
+	void download( const QString & _path, QBuffer * _target,
+						bool _wait = false ) const;
+
+	QHttp * m_http;
+	QBuffer m_indexBuffer;
+	static QList<int> m_downloadIDs;
 
 } ;
 

src/core/web_resources_provider.cpp

@@ -0,0 +1,150 @@
+/*
+ * web_resources_provider.cpp - implementation of WebResourcesProvider^
+ *
+ * Copyright (c) 2009 Tobias Doerffel <tobydox/at/users.sourceforge.net>
+ * 
+ * This file is part of Linux MultiMedia Studio - http://lmms.sourceforge.net
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, 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 General Public
+ * License along with this program (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <QtCore/QCoreApplication>
+#include <QtCore/QDebug>
+#include <QtCore/QUrl>
+#include <QtNetwork/QHttp>
+
+#include "web_resources_provider.h"
+#include "resources_db.h"
+
+
+QList<int> WebResourcesProvider::m_downloadIDs;
+
+
+WebResourcesProvider::WebResourcesProvider( const QString & _url ) :
+	ResourcesProvider( _url ),
+	m_http( NULL ),
+	m_indexBuffer()
+{
+	QUrl u( _url );
+	m_http = new QHttp( u.host(), u.port() > 0 ? u.port() : 80, this );
+	connect( m_http, SIGNAL( requestFinished( int, bool ) ),
+			this, SLOT( finishDownload( int, bool ) ) );
+
+	database()->init();
+}
+
+
+
+
+WebResourcesProvider::~WebResourcesProvider()
+{
+	database()->save( localCacheFile() );
+}
+
+
+
+
+void WebResourcesProvider::updateDatabase( void )
+{
+	m_indexBuffer.close();
+	m_indexBuffer.open( QBuffer::ReadWrite );
+	download( "/WebResources/Index", &m_indexBuffer, true );
+
+	m_indexBuffer.seek( 0 );
+
+	QDomDocument doc;
+	doc.setContent( &m_indexBuffer );
+
+	importNodeIntoDB( doc.firstChildElement( "webresources" ),
+						database()->topLevelNode() );
+}
+
+
+
+
+QByteArray WebResourcesProvider::fetchData( const ResourcesItem * _item,
+							int _maxSize ) const
+{
+	QBuffer buffer;
+	buffer.open( QBuffer::ReadWrite );
+
+	download( "/WebResources/" + _item->hash(), &buffer, true );
+
+	return buffer.data();
+}
+
+
+
+
+void WebResourcesProvider::finishDownload( int _id, bool a )
+{
+	m_downloadIDs.removeAll( _id );
+}
+
+
+
+
+void WebResourcesProvider::importNodeIntoDB( const QDomNode & _n,
+						ResourcesTreeItem * _parent )
+{
+	QDomNode n = _n;
+	while( !n.isNull() )
+	{
+		ResourcesItem * item =
+			new ResourcesItem( this,
+				n.firstChildElement( "name" ).text(),
+				ResourcesItem::TypeUnknown,
+				ResourcesItem::BaseURL,
+				n.firstChildElement( "dir" ).text(),
+				n.firstChildElement( "hash" ).text(),
+				n.firstChildElement( "tags" ).text(),
+				n.firstChildElement( "size" ).text().toInt() );
+		database()->addItem( item );
+
+		ResourcesTreeItem * treeItem =
+					new ResourcesTreeItem( _parent, item );
+		if( n.nodeName() != "file" )
+		{
+			importNodeIntoDB( n.firstChild(), treeItem );
+		}
+		n = n.nextSibling();
+	}
+}
+
+
+
+
+
+void WebResourcesProvider::download( const QString & _path,
+					QBuffer * _target, bool _wait ) const
+{
+	const int id = m_http->get( _path, _target );
+	m_downloadIDs << id;
+
+	if( _wait )
+	{
+		while( m_downloadIDs.contains( id ) )
+		{
+			QCoreApplication::instance()->processEvents();
+		}
+	}
+}
+
+
+
+#include "moc_web_resources_provider.cxx"
+