How to Enable BindValidation after it is diabled using gin.DisableBindValidation

[NishantG01]

Description

I want to limit the impact of gin.DisableBindValidation within a function and should be able to re-enable it.
Currently, I have many routes, all the routes need the gin validation and few routes need to consume the incoming request modify the data and then do the validation again

IF I use gin.DisableBindValidation, all the other routes get impacted.

How to reproduce

1. gin.DisableBindValidation
2. add some required field
3. send the request for route /api/v1/get - this works as it is but
4. the other registered routes which require field validation, don't work

package main

import (
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
	"reflect"
	"strings"

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

type User struct {
	Email string `json:"email" form:"e-mail" binding:"required"`
	Name  string `json:"name" binding:"required"`
        Org string `json:"org" binding:required"`
}

func main() {
	route := gin.Default()
	route.POST("/user", validateUser)
        route.GET("/validate",validateUsers)
	route.Run(":8085")
}

func validateUser(c *gin.Context) {
	var u User
	if err := c.ShouldBindJSON(&u); err == nil {
		c.JSON(http.StatusOK, gin.H{"message": "User validation successful."})
	} else {
		c.JSON(http.StatusBadRequest, gin.H{"errors": err.Error()})
		return
	}
}
func validateUsers(c *gin.Context) {
	var u []User
        gin.DisableBindValidation().  
//Note: As soon as this route gets executed the validateUser route will stop validating the json
	if err := c.ShouldBindJSON(&u); err == nil {
		c.JSON(http.StatusOK, gin.H{"message": "User validation successful."})
	} else {
		c.JSON(http.StatusBadRequest, gin.H{"errors": MarshalErr(*jsErr)})
		return
	}
        for _,user:=range u{
                 u.Org="asb"
        }
        //enable bind validation
       //revalidate the struct array
}

Expectations

The data is validated for array request after adding the missing required field as well as with single request

Actual result

The /users requests start failing once gin.DisableBindValidation is called.

Environment

• go version:
• gin version (or commit ref):
• operating system:

[jimbirthday]

@NishantG01
I found a function under the test unit

github.com/gin-gonic/gin@v1.7.3/binding/binding_test.go

I refer to the writing of this unit test

import (
	"github.com/gin-gonic/gin"
	"github.com/gin-gonic/gin/binding"
	"net/http"
)

type User struct {
	Email string `json:"email" form:"e-mail" binding:"required"`
	Name  string `json:"name" binding:"required"`
	Org   string `json:"org" binding:"required"`
}

func main() {
	route := gin.Default()
	route.POST("/user", validateUser)
	route.GET("/validate", validateUsers)
	route.Run(":8085")
}

func validateUser(c *gin.Context) {
	var u User
	if err := c.ShouldBindJSON(&u); err == nil {
		c.JSON(http.StatusOK, gin.H{"message": "User validation successful."})
	} else {
		c.JSON(http.StatusBadRequest, gin.H{"errors": err.Error()})
		return
	}
}
func validateUsers(c *gin.Context) {
	var u []User
	backup := binding.Validator
	defer func() {binding.Validator = backup}()
	gin.DisableBindValidation()
	//Note: As soon as this route gets executed the validateUser route will stop validating the json
	if err := c.ShouldBindJSON(&u); err == nil {
		c.JSON(http.StatusOK, gin.H{"message": "User validation successful."})
	} else {
		c.JSON(http.StatusBadRequest, gin.H{"errors":err.Error()})
		return
	}
}

1. /validate

2. /user

I hope this is the result you want

[NishantG01]

@jimbirthday,

Thanks for your response. Appreciate it.
The issue with this approach is that the concurrent calls will pass through as soon as the gin.DisableBindValidation() is executed.
Meaning if any request comes for /user, while /validate executed gin.DisableBindValidation,
func validateUser will not check for Binding validation.

[jimbirthday]

@NishantG01

Then you may be able to use a custom tag verification method to prevent a special tag from being validated.

Something like this:

	if v, ok := binding.Validator.Engine().(*validator.Validate); ok {
		v.RegisterValidation("bookabledate", bookableDate)
	}

[jimbirthday]

@NishantG01

link : https://blog.depa.do/post/gin-validation-errors-handling