time_format tag not work with json tag

[just-pthai-it]

I read this example from official docs: https://gin-gonic.com/docs/examples/custom-validators/

package main

import (
	"net/http"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/gin-gonic/gin/binding"
	"github.com/go-playground/validator/v10"
)

// Booking contains binded and validated data.
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.After(date) {
			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(":8085")
}

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()})
	}
}

And I try to apply time_format tag to my struct

package teacher_form

import "time"

type CreateTeacherFormRequest struct {
   Birth time.Time `json:"birth" form:"birth" binding:"required" time_format:"2006-01-02"`
}

When I send POST request using formData , the validation work well. But if I send POST request with json payload. Gin fw not validate anything at all.
It seem like the time_format only work with formData? How can I validate POST request input field with the specific time format. For example just only date: 2006-01-02.

[RedCrazyGhost]

Since golang json uses the RFC3339 specification, you can access it with the following request parameters

{
    "birth":"2024-06-17T15:04:05+08:00"
}

see #1193