base-golang/pkg/database/tool.go
2024-07-23 10:23:43 +08:00

89 lines
1.5 KiB
Go

package database
import (
"database/sql"
"database/sql/driver"
"encoding/json"
"fmt"
"gorm.io/gorm"
"reflect"
)
type NullTime sql.NullTime
func (n *NullTime) Scan(value any) error {
return (*sql.NullTime)(n).Scan(value)
}
func (n NullTime) Value() (driver.Value, error) {
if !n.Valid {
return nil, nil
}
return n.Time, nil
}
func (n NullTime) MarshalJSON() ([]byte, error) {
if n.Valid {
return json.Marshal(n.Time)
}
return json.Marshal(nil)
}
func (n *NullTime) UnmarshalJSON(b []byte) error {
if string(b) == "null" {
n.Valid = false
return nil
}
err := json.Unmarshal(b, &n.Time)
if err == nil {
n.Valid = true
}
return err
}
/*-----------------------------------------------------------*/
type PaginateList struct {
Page int64 `json:"page"`
Size int64 `json:"size"`
Total int64 `json:"total"`
List any `json:"list"`
}
func Paginate(db *gorm.DB, model any, page, size int64) (*PaginateList, error) {
ptr := reflect.ValueOf(model)
if ptr.Kind() != reflect.Ptr {
return nil, fmt.Errorf("model must be pointer")
}
var total int64
err := db.Model(model).Count(&total).Error
if err != nil {
return &PaginateList{
Page: page,
Size: size,
Total: total,
List: make([]any, 0),
}, err
}
offset := size * (page - 1)
err = db.Limit(int(size)).Offset(int(offset)).Find(model).Error
if err != nil {
return &PaginateList{
Page: page,
Size: size,
Total: total,
List: make([]any, 0),
}, err
}
return &PaginateList{
Page: page,
Size: size,
Total: total,
List: model,
}, nil
}