Improve reconnection policy and context handling in Queryx

queryx_wrap.go

@@ -86,6 +86,9 @@ func (q *Queryx) RoutingKey(routingKey []byte) *Queryx {
 // query, queries will be canceled and return once the context is
 // canceled.
 func (q *Queryx) WithContext(ctx context.Context) *Queryx {
+	if ctx == nil {
+		ctx = context.Background()
+	}
 	q.Query = q.Query.WithContext(ctx)
 	return q
 }