Only option

app/repository/options.go

@@ -0,0 +1,61 @@
+package repository
+
+import (
+	"fmt"
+
+	"gorm.io/gorm"
+)
+
+type Pagination struct {
+	Offset int
+	Limit  int
+}
+
+type OrderDirection string
+
+const (
+	OrderASC  OrderDirection = "ASC"
+	OrderDESC OrderDirection = "DESC"
+)
+
+type Order struct {
+	Field     string
+	Direction OrderDirection
+}
+
+func applyOptionOnly(query *gorm.DB, only *[]string) *gorm.DB {
+	if only == nil || len(*only) == 0 {
+		return query
+	}
+	query = query.Select(*only)
+	return query
+}
+
+func applyOptionOrdering(query *gorm.DB, ordering *[]Order) *gorm.DB {
+	if ordering == nil || len(*ordering) == 0 {
+		return query
+	}
+
+	for _, order := range *ordering {
+		if len(order.Direction) == 0 || order.Direction == OrderASC {
+			query = query.Order(order.Field)
+		} else {
+			query = query.Order(fmt.Sprintf("%s %s", order.Field, order.Direction))
+		}
+	}
+	return query
+}
+
+func applyOptionPagination(query *gorm.DB, pagination *Pagination) *gorm.DB {
+	if pagination == nil {
+		return query
+	}
+
+	if pagination.Limit != 0 {
+		query = query.Limit(pagination.Limit)
+	}
+	if pagination.Offset != 0 {
+		query = query.Offset(pagination.Offset)
+	}
+	return query
+}