介绍
本文介绍了如何在gin框架中自定义验证器，并加以案例说明。
案例
源码：
package main
import (
"net/http"
"time"
"github.com/gin-gonic/gin"
"github.com/gin-gonic/gin/binding"
"github.com/go-playground/validator/v10"
)
// Booking 包含绑定和验证的数据。
type Booking struct {
CheckIn time.Time `form:"check_in" binding:"required,bookabledate" time_format:"2006-01-02"`
CheckOut time.Time `form:"check_out" binding:"required,gtfield=CheckIn,bookabledate" time_format:"2006-01-02"`
}
var bookableDate validator.Func = func(fl validator.FieldLevel) bool {
date, ok := fl.Field().Interface().(time.Time)
if ok {
today := time.Now()
if today.Year() > date.Year() || today.YearDay() > date.YearDay() {
return false
}
}
return true
}
func main() {
route := gin.Default()
if v, ok := binding.Validator.Engine().(*validator.Validate); ok {
v.RegisterValidation("bookabledate", bookableDate)
}
route.GET("/bookable", getBookable)
route.Run(":8080")
}
func getBookable(c *gin.Context) {
var b Booking
if err := c.ShouldBindWith(&b, binding.Query); err == nil {
c.JSON(http.StatusOK, gin.H{"message": "Booking dates are valid!"})
} else {
c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
}
}
注： 官方文档中通过 today.After(date) 作为判断依据，该方法不准确，会导致一直为false， 因此可以调整为 today.Year() > date.Year() || today.YearDay() > date.YearDay()
测试：
http://127.0.0.1:8080/bookable?check_in=2022-04-01&check_out=2022-04-02
{
"message": "Booking dates are valid!"
}
http://127.0.0.1:8080/bookable?check_in=2022-04-01&check_out=2022-04-01
{
"error": "Key: 'Booking.CheckOut' Error:Field validation for 'CheckOut' failed on the 'gtfield' tag"
}
说明
gin官方文档 自定义验证器
gin-gonic/examples-> Struct level validations
gin自定义验证器转化中文
