From e115124075ccf777eaeccc1a2d6a81529a4c1951 Mon Sep 17 00:00:00 2001
From: Tobias Doerffel <tobias.doerffel@gmail.com>
Date: Fri, 17 Jul 2009 11:44:57 +0200
Subject: [PATCH] WebResourcesProvider: support for HTTP forwardings + cleanups

Properly handle HTTP status code 302 which indicates a moved site,
i.e. try to fetch data from the new location. This finally makes
WebResources work again with LSP being moved to http://lmms.info.

Furthermore cleaned up code a bit. There's no need for a global
QHttp object or a global QBuffer object. Instead allocate them on
the stack in the according methods.

Furthermore removed unused/incomplete support for non-blocking download.
We should introduce support for a ProgressDialog solution (also allowing
to cancel operations) later.

Signed-off-by: Tobias Doerffel <tobias.doerffel@gmail.com>
---
 include/WebResourceProvider.h    | 14 +++-----
 src/core/WebResourceProvider.cpp | 58 ++++++++++++++++++++------------
 2 files changed, 42 insertions(+), 30 deletions(-)

diff --git a/include/WebResourceProvider.h b/include/WebResourceProvider.h
index 571c2a1a7..12976cf76 100644
--- a/include/WebResourceProvider.h
+++ b/include/WebResourceProvider.h
@@ -25,14 +25,13 @@
 #ifndef _WEB_RESOURCE_PROVIDER_H
 #define _WEB_RESOURCE_PROVIDER_H
 
-#include <QtCore/QBuffer>
 #include <QtXml/QDomNode>
 
 #include "ResourceProvider.h"
 #include "ResourceItem.h"
 
 
-class QHttp;
+class QBuffer;
 
 
 class WebResourceProvider : public ResourceProvider
@@ -42,12 +41,12 @@ public:
 	WebResourceProvider( const QString & _url );
 	virtual ~WebResourceProvider();
 
-	virtual QString providerName( void ) const
+	virtual QString providerName() const
 	{
 		return "WebResourceProvider";
 	}
 
-	virtual void updateDatabase( void );
+	virtual void updateDatabase();
 
 	virtual int dataSize( const ResourceItem * _item ) const
 	{
@@ -58,7 +57,7 @@ public:
 	virtual QByteArray fetchData( const ResourceItem * _item,
 					int _maxSize = -1 ) const;
 
-	virtual bool isLocal( void ) const
+	virtual bool isLocal() const
 	{
 		return false;
 	}
@@ -73,11 +72,8 @@ private:
 						ResourceItem * _item );
 	void importNodeIntoDB( const QDomNode & n,
 						ResourceTreeItem * _parent );
-	void download( const QString & _path, QBuffer * _target,
-						bool _wait = false ) const;
+	void download( const QString & _path, QBuffer * _target ) const;
 
-	QHttp * m_http;
-	QBuffer m_indexBuffer;
 	static QList<int> m_downloadIDs;
 
 } ;
diff --git a/src/core/WebResourceProvider.cpp b/src/core/WebResourceProvider.cpp
index 414fe43d6..baecfaaee 100644
--- a/src/core/WebResourceProvider.cpp
+++ b/src/core/WebResourceProvider.cpp
@@ -22,6 +22,7 @@
  *
  */
 
+#include <QtCore/QBuffer>
 #include <QtCore/QCoreApplication>
 #include <QtCore/QDebug>
 #include <QtCore/QUrl>
@@ -35,15 +36,8 @@ QList<int> WebResourceProvider::m_downloadIDs;
 
 
 WebResourceProvider::WebResourceProvider( const QString & _url ) :
-	ResourceProvider( _url ),
-	m_http( NULL ),
-	m_indexBuffer()
+	ResourceProvider( _url )
 {
-	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();
 }
 
@@ -58,16 +52,16 @@ WebResourceProvider::~WebResourceProvider()
 
 
 
-void WebResourceProvider::updateDatabase( void )
+void WebResourceProvider::updateDatabase()
 {
-	m_indexBuffer.close();
-	m_indexBuffer.open( QBuffer::ReadWrite );
-	download( "/WebResources/Index", &m_indexBuffer, true );
+	QBuffer indexBuffer;
+	indexBuffer.open( QBuffer::ReadWrite );
+	download( url() + "/WebResources/Index", &indexBuffer );
 
-	m_indexBuffer.seek( 0 );
+	indexBuffer.seek( 0 );
 
 	QDomDocument doc;
-	doc.setContent( &m_indexBuffer );
+	doc.setContent( &indexBuffer );
 
 	importNodeIntoDB( doc.firstChildElement( "webresources" ),
 						database()->topLevelNode() );
@@ -82,7 +76,7 @@ QByteArray WebResourceProvider::fetchData( const ResourceItem * _item,
 	QBuffer buffer;
 	buffer.open( QBuffer::ReadWrite );
 
-	download( "/WebResources/" + _item->hash(), &buffer, true );
+	download( url() + "/WebResources/" + _item->hash(), &buffer );
 
 	return buffer.data();
 }
@@ -198,17 +192,39 @@ void WebResourceProvider::importNodeIntoDB( const QDomNode & _n,
 
 
 void WebResourceProvider::download( const QString & _path,
-					QBuffer * _target, bool _wait ) const
+					QBuffer * _target ) const
 {
-	const int id = m_http->get( _path, _target );
+	// create local http object;
+	QHttp http;
+	connect( &http, SIGNAL( requestFinished( int, bool ) ),
+			this, SLOT( finishDownload( int, bool ) ) );
 
-	if( _wait )
+	// set current URL for http object
+	QUrl u( _path );
+	http.setHost( u.host(), u.port() > 0 ? u.port() : 80 );
+
+	// start the download
+	const int id = http.get( _path, _target );
+
+	// wait for the download to finish
+	while( !m_downloadIDs.contains( id ) )
 	{
-		while( !m_downloadIDs.contains( id ) )
+		QCoreApplication::instance()->processEvents();
+	}
+	m_downloadIDs.removeAll( id );
+
+	if( http.lastResponse().statusCode() == 302 )
+	{
+		const QString newLocation =
+				http.lastResponse().value( "location" );
+		if( newLocation != _path )
 		{
-			QCoreApplication::instance()->processEvents();
+			qDebug() << "HTTP forwarding to" << newLocation;
+
+			_target->seek( 0 );
+			_target->buffer().clear();
+			download( newLocation, _target );
 		}
-		m_downloadIDs.removeAll( id );
 	}
 }