Use HttpMetaCache to minimize network use.

1 files changed, 111 insertions, 0 deletions

diff --git a/logic/net/FileDownload.cpp b/logic/net/FileDownload.cpp
new file mode 100644
index 00000000..aad4a991
--- /dev/null
+++ b/logic/net/FileDownload.cpp
@@ -0,0 +1,111 @@
+#include "MultiMC.h"
+#include "FileDownload.h"
+#include <pathutils.h>
+#include <QCryptographicHash>
+#include <QDebug>
+
+
+FileDownload::FileDownload ( QUrl url, QString target_path )
+	:Download()
+{
+	m_url = url;
+	m_target_path = target_path;
+	m_check_md5 = false;
+	m_status = Job_NotStarted;
+	m_opened_for_saving = false;
+}
+
+void FileDownload::start()
+{
+	QString filename = m_target_path;
+	m_output_file.setFileName ( filename );
+	// if there already is a file and md5 checking is in effect and it can be opened
+	if ( m_output_file.exists() && m_output_file.open ( QIODevice::ReadOnly ) )
+	{
+		// check the md5 against the expected one
+		QString hash = QCryptographicHash::hash ( m_output_file.readAll(), QCryptographicHash::Md5 ).toHex().constData();
+		m_output_file.close();
+		// skip this file if they match
+		if ( m_check_md5 && hash == m_expected_md5 )
+		{
+			qDebug() << "Skipping " << m_url.toString() << ": md5 match.";
+			emit succeeded(index_within_job);
+			return;
+		}
+		else
+		{
+			m_expected_md5 = hash;
+		}
+	}
+	if(!ensureFilePathExists(filename))
+	{
+		emit failed(index_within_job);
+		return;
+	}
+	
+	qDebug() << "Downloading " << m_url.toString();
+	QNetworkRequest request ( m_url );
+	request.setRawHeader(QString("If-None-Match").toLatin1(), m_expected_md5.toLatin1()); 
+	
+	auto worker = MMC->qnam();
+	QNetworkReply * rep = worker->get ( request );
+	
+	m_reply = QSharedPointer<QNetworkReply> ( rep, &QObject::deleteLater );
+	connect ( rep, SIGNAL ( downloadProgress ( qint64,qint64 ) ), SLOT ( downloadProgress ( qint64,qint64 ) ) );
+	connect ( rep, SIGNAL ( finished() ), SLOT ( downloadFinished() ) );
+	connect ( rep, SIGNAL ( error ( QNetworkReply::NetworkError ) ), SLOT ( downloadError ( QNetworkReply::NetworkError ) ) );
+	connect ( rep, SIGNAL ( readyRead() ), SLOT ( downloadReadyRead() ) );
+}
+
+void FileDownload::downloadProgress ( qint64 bytesReceived, qint64 bytesTotal )
+{
+	emit progress (index_within_job, bytesReceived, bytesTotal );
+}
+
+void FileDownload::downloadError ( QNetworkReply::NetworkError error )
+{
+	// error happened during download.
+	// TODO: log the reason why
+	m_status = Job_Failed;
+}
+
+void FileDownload::downloadFinished()
+{
+	// if the download succeeded
+	if ( m_status != Job_Failed )
+	{
+		// nothing went wrong...
+		m_status = Job_Finished;
+		m_output_file.close();
+
+		m_reply.clear();
+		emit succeeded(index_within_job);
+		return;
+	}
+	// else the download failed
+	else
+	{
+		m_output_file.close();
+		m_reply.clear();
+		emit failed(index_within_job);
+		return;
+	}
+}
+
+void FileDownload::downloadReadyRead()
+{
+	if(!m_opened_for_saving)
+	{
+		if ( !m_output_file.open ( QIODevice::WriteOnly ) )
+		{
+			/*
+			* Can't open the file... the job failed
+			*/
+			m_reply->abort();
+			emit failed(index_within_job);
+			return;
+		}
+		m_opened_for_saving = true;
+	}
+	m_output_file.write ( m_reply->readAll() );
+}