fix MSSQL bug on org (#3405)

vendor/github.com/go-xorm/xorm/context.go

@@ -0,0 +1,26 @@
+// Copyright 2017 The Xorm Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.8
+
+package xorm
+
+import "context"
+
+// PingContext tests if database is alive
+func (engine *Engine) PingContext(ctx context.Context) error {
+	session := engine.NewSession()
+	defer session.Close()
+	return session.PingContext(ctx)
+}
+
+// PingContext test if database is ok
+func (session *Session) PingContext(ctx context.Context) error {
+	if session.isAutoClose {
+		defer session.Close()
+	}
+
+	session.engine.logger.Infof("PING DATABASE %v", session.engine.DriverName())
+	return session.DB().PingContext(ctx)
+}