Required on "map" are not working

[tiagoacardoso]

Hi there!

Today I just found out that for example map[string]string
Just had a look on the source code but my knowledge is not enough to solve the problem.
Even adding a CustomRule it doesn't work, seems to be an internal problem in the source code.

Code:

func validate(c *gin.Context) {
	type Example struct {
		Foo string            `json:"foo"`
		Bar map[string]string `json:"bar"`
	}

	rules :=
		govalidator.MapData{
			"foo": []string{"required"},
			"bar": []string{"required"},
		}

	var ex Example
	opts := govalidator.Options{
		Request: c.Request,
		Rules:   rules,
		Data:    &ex,
	}
	v := govalidator.New(opts)
	e := v.ValidateJSON()
	if len(e) > 0 {
		validationErrors := map[string]interface{}{"validation_errors": e}
		c.JSON(http.StatusBadRequest, validationErrors)
		return
	}
}

Input:

{
    "foo": "asd",
    "bar": {
    	"1": "one"
    }
}

Output:

{
    "validation_errors": {
        "bar": [
            "The bar field is required"
        ]
    }
}

Best regards :)