golang gorm mysql 读写时间戳

gorm直接写time.Time类型时，会报错

解决方案

1. 在打开数据库命令中加入parseTime=true&loc=Local

   例如：root:1234567@tcp(127.0.0.1:3306)/dbName?charset=utf8&parseTime=true&loc=Local&timeout=1000ms

2. 自定义自己的time类型，用于数据库读写

package types

import (
    "database/sql/driver"
    "fmt"
    "time"
)

// Time is alias type for time.Time
type Time time.Time

const (
    timeFormart = "2006-01-02 15:04:05"
    zone        = "Asia/Shanghai"
)

// UnmarshalJSON implements json unmarshal interface.
func (t *Time) UnmarshalJSON(data []byte) (err error) {
    now, err := time.ParseInLocation(`"`+timeFormart+`"`, string(data), time.Local)
    *t = Time(now)
    return
}

// MarshalJSON implements json marshal interface.
func (t Time) MarshalJSON() ([]byte, error) {
    b := make([]byte, 0, len(timeFormart)+2)
    b = append(b, '"')
    b = time.Time(t).AppendFormat(b, timeFormart)
    b = append(b, '"')
    return b, nil
}

func (t Time) String() string {
    return time.Time(t).Format(timeFormart)
}

func (t Time) local() time.Time {
    loc, _ := time.LoadLocation(zone)
    return time.Time(t).In(loc)
}

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

// Scan valueof time.Time 注意是指针类型 method
func (t *Time) Scan(v interface{}) error {
    value, ok := v.(time.Time)
    if ok {
        *t = Time(value)
        return nil
    }
    return fmt.Errorf("can not convert %v to timestamp", v)
}

原理 自定义数据库数据类型,在 sql driver 中实现自定义类型需要实现 Scanner和Valuer接口

Scanner

type Scanner interface {
    Scan(src interface{}) error
}

Valuer

type Valuer interface {
    // Value returns a driver Value.
    Value() (Value, error)
}

unmarshal和marshal 自定义 json 转换格式

本文用作学习笔记，参考转载了 gorm 处理时间戳 的内容，如若侵权，请联系删除。