GORM 格式化时间字段
转载： https://blog.csdn.net/m0_38112165/article/details/119081947

package main

import (
    "database/sql/driver"
    "encoding/json"
    "fmt"
    "time"

    "gorm.io/driver/mysql"
    "gorm.io/gorm"
)

type LocalTime struct {
    time.Time
}

func (t LocalTime) MarshalJSON() ([]byte, error) {
    return []byte(fmt.Sprintf("\"%s\"", t.Format("2006-01-02 15:04:05"))), nil
}

func (t LocalTime) Value() (driver.Value, error) {
    var zeroTime time.Time
    if t.Time.UnixNano() == zeroTime.UnixNano() {
        return nil, nil
    }
    return t.Time, nil
}

func (t *LocalTime) Scan(v interface{}) error {
    value, ok := v.(time.Time)
    if ok {
        *t = LocalTime{Time: value}
        return nil
    }
    return fmt.Errorf("can not convert %v to timestamp", v)
}

type Model struct {
    CreatedAt *LocalTime `json:"create_time" grom:"autoCreateTime"`
    UpdatedAt *LocalTime `json:"update_time"`
}
type Test struct {
    ID   uint   `gorm:"primaryKey"`
    Name string `json:"name" gorm:"column:name;type:varchar(255)"`
    Model
}

func main() {
    dsn := mysql.Open("root:root@tcp(10.20.0.200:3306)/test_code?charset=utf8&parseTime=True&loc=Local")
    db, err := gorm.Open(dsn, &gorm.Config{})
    if err != nil {
        panic(err)
    }
    // db.AutoMigrate(&Test{})
    // db.Model(&Test{}).Create(&Test{Name: "0001"})
    var test Test = Test{ID: 1}
    db.Model(&test).First(&test)
    j, err := json.Marshal(&test)
    if err != nil {
        panic(err)
    }
    fmt.Printf("j: %v\n", string(j))
}