I have an application written with golang gin framework
. I want to write a middleware to customize all error messages specially in the case of BindJSON
.
Here is the middleware:
func Errors() gin.HandlerFunc {
return func(c *gin.Context) {
c.Next()
// Only run if there are some errors to handle
if len(c.Errors) > 0 {
for _, e := range c.Errors {
// Find out what type of error it is
switch e.Type {
case gin.ErrorTypePublic:
// Only output public errors if nothing has been written yet
if !c.Writer.Written() {
c.JSON(c.Writer.Status(), gin.H{"Error": e.Error()})
}
case gin.ErrorTypeBind:
errs := e.Err.(validator.ValidationErrors)
list := make(map[int]string)
fmt.Println(errs)
for field, err := range errs {
list[field] = validationErrorToText(err)
}
// Make sure we maintain the preset response status
status := http.StatusBadRequest
if c.Writer.Status() != http.StatusOK {
status = c.Writer.Status()
}
c.JSON(status, gin.H{"Errors": list})
default:
c.JSON(http.StatusBadRequest, gin.H{"Errors": c.Errors.JSON()})
}
}
// If there was no public or bind error, display default 500 message
if !c.Writer.Written() {
c.JSON(http.StatusInternalServerError, gin.H{"Error": errorInternalError.Error()})
}
}
}
}
The functionality is so simple, it gets all the gin
errors and do something based on error type! the problem is in case of gin.ErrorTypeBind
when i've tried to map errors to validation errors: e.Err.(validator.ValidationErrors)
.
I've got this error
interface conversion: error is validator.ValidationErrors, not validator.ValidationErrors (types from different packages)
here is the list of imported packages:
import (
"errors"
"fmt"
"net/http"
"github.com/gin-gonic/gin"
"gopkg.in/go-playground/validator.v9"
)