Files
repo-pattern/app/repository/method_list.go
2024-06-24 00:45:54 +02:00

82 lines
1.4 KiB
Go

package repository
import (
"fmt"
"repo-pattern/app/repository/smartfilter"
"gorm.io/gorm"
"gorm.io/gorm/schema"
)
type Pagination struct {
Offset int
Limit int
}
type OrderDirection string
const (
OrderASC OrderDirection = "ASC"
OrderDESC OrderDirection = "DESC"
)
type Order struct {
Field string
Direction OrderDirection
}
type ListMethod[T schema.Tabler] struct {
DbConn *gorm.DB
}
func (m *ListMethod[T]) Init(dbConn *gorm.DB) {
m.DbConn = dbConn
}
func applyOrdering(query *gorm.DB, ordering *[]Order) *gorm.DB {
if ordering == nil || len(*ordering) == 0 {
return query
}
for _, order := range *ordering {
if order.Direction == OrderASC {
query = query.Order(order.Field)
} else {
query = query.Order(fmt.Sprintf("%s %s", order.Field, order.Direction))
}
}
return query
}
func applyPagination(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
}
func (m ListMethod[T]) List(filter interface{}, ordering *[]Order, pagination *Pagination) (*[]T, error) {
var (
model T
models []T
)
query, err := smartfilter.ToQuery(model, filter, m.DbConn)
if err != nil {
return nil, err
}
query = applyOrdering(query, ordering)
query = applyPagination(query, pagination)
query.Find(&models)
return &models, nil
}