Add onclose callback

mongox/query/callbacks.go

@@ -7,7 +7,10 @@ import (
 type Callback func(ctx context.Context, iter interface{}) (err error)
 type Callbacks []Callback
 
-type OnDecode Callback
+type (
+	OnDecode Callback
+	OnClose  Callback
+)
 
 // Invoke callbacks sequence
 func (c Callbacks) Invoke(ctx context.Context, iter interface{}) (err error) {

mongox/query/compose.go

@@ -130,8 +130,13 @@ func applyCallbacks(q *Query, f interface{}) (ok bool) {
 	switch cb := f.(type) {
 	case OnDecode:
 		q.ondecode = append(q.ondecode, Callback(cb))
-		ok = true
+	case OnClose:
+		q.onclose = append(q.onclose, Callback(cb))
+	default:
+		return
 	}
 
+	ok = true
+
 	return
 }

mongox/query/query.go

@@ -12,6 +12,7 @@ type Query struct {
 	skipper   Skipper
 	preloader Preloader
 	ondecode  Callbacks
+	onclose   Callbacks
 }
 
 // And function pushes the elem query to the $and array of the query
@@ -81,6 +82,10 @@ func (q *Query) OnDecode() (callbacks Callbacks) {
 	return q.ondecode
 }
 
+func (q *Query) OnClose() (callbacks Callbacks) {
+	return q.onclose
+}
+
 // Empty checks the query for any content
 func (q *Query) Empty() (isEmpty bool) {
 	return len(q.m) == 0