add func for directly adding sorting parameters

Author: timsolov

main.go

@@ -188,6 +188,15 @@ func (p *Query) HaveSortBy(by string) bool {
 return false
 }
 
+// AddSortBy adds an order rule to Query
+func (q *Query) AddSortBy(by string, desc bool) *Query {
+q.Sorts = append(q.Sorts, Sort{
+By: by,
+Desc: desc,
+})
+return q
+}
+
 // HaveFilter returns true if request contains some filter
 func (p *Query) HaveFilter(name string) bool {