From 4d06e8f7b520625d743816afbd9e0dc6945a25db Mon Sep 17 00:00:00 2001
From: Dirk Hohndel <dirk@hohndel.org>
Date: Fri, 12 Jun 2015 06:31:16 -0700
Subject: Cloud storage: check connection before connecting

libgit2 takes forever (a minute or so) to figure out that it can't connect
to a remote server.
So if we are using https as connection protocol, quickly check utilizing
RFCs 2324/7168 to make sure we can reach the cloud server (and not some
captive portal or something).

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
---
 qt-ui/subsurfacewebservices.cpp | 46 ++++++++++++++++++++++++++++++++++++++++-
 qt-ui/subsurfacewebservices.h   |  7 +++++++
 2 files changed, 52 insertions(+), 1 deletion(-)

(limited to 'qt-ui')

diff --git a/qt-ui/subsurfacewebservices.cpp b/qt-ui/subsurfacewebservices.cpp
index 825d4f03d..16faac61d 100644
--- a/qt-ui/subsurfacewebservices.cpp
+++ b/qt-ui/subsurfacewebservices.cpp
@@ -944,7 +944,6 @@ QNetworkReply* UserSurveyServices::sendSurvey(QString values)
 CloudStorageAuthenticate::CloudStorageAuthenticate(QObject *parent) : QObject(parent)
 {
 	userAgent = getUserAgent();
-
 }
 
 #define CLOUDURL "https://cloud.subsurface-divelog.org/"
@@ -998,3 +997,48 @@ void CloudStorageAuthenticate::sslErrors(QList<QSslError> errorList)
 		qDebug() << err.errorString();
 	}
 }
+
+CheckCloudConnection::CheckCloudConnection(QObject *parent)
+{
+
+}
+
+#define TEAPOT "https://cloud.subsurface-divelog.org/make-latte?number-of-shots=3"
+#define HTTP_I_AM_A_TEAPOT 418
+#define MILK "Linus does not like non-fat milk"
+bool CheckCloudConnection::checkServer()
+{
+	QTimer timer;
+	timer.setSingleShot(true);
+	QEventLoop loop;
+	QNetworkRequest request;
+	request.setRawHeader("Accept", "text/plain");
+	request.setRawHeader("User-Agent", getUserAgent().toUtf8());
+	request.setUrl(QString(TEAPOT));
+	QNetworkAccessManager *mgr = new QNetworkAccessManager();
+	QNetworkReply *reply = mgr->get(request);
+	connect(&timer, SIGNAL(timeout()), &loop, SLOT(quit()));
+	connect(reply, SIGNAL(finished()), &loop, SLOT(quit()));
+	timer.start(2000); // wait two seconds
+	loop.exec();
+	if (timer.isActive()) {
+		// didn't time out, did we get the right response?
+		timer.stop();
+		if (reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt() == HTTP_I_AM_A_TEAPOT &&
+		    reply->readAll() == QByteArray(MILK)) {
+			reply->deleteLater();
+			mgr->deleteLater();
+			return true;
+		}
+		// qDebug() << "did not get expected response - server unreachable" <<
+		//	    reply->error() << reply->errorString() <<
+		//	    reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt() <<
+		//	    reply->readAll();
+	} else {
+		disconnect(reply, SIGNAL(finished()), &loop, SLOT(quit()));
+		reply->abort();
+	}
+	reply->deleteLater();
+	mgr->deleteLater();
+	return false;
+}
diff --git a/qt-ui/subsurfacewebservices.h b/qt-ui/subsurfacewebservices.h
index 6f8d6279a..d08f64aa8 100644
--- a/qt-ui/subsurfacewebservices.h
+++ b/qt-ui/subsurfacewebservices.h
@@ -129,6 +129,13 @@ private:
 
 };
 
+class CheckCloudConnection : public QObject {
+	Q_OBJECT
+public:
+	explicit CheckCloudConnection(QObject *parent = 0);
+	static bool checkServer();
+};
+
 #ifdef __cplusplus
 extern "C" {
 #endif
-- 
cgit v1.2.3-70-g09d2