func (r ResponseError) ToJSON() string {
	body, err := json.Marshal(r)
	if err != nil {
		return ""
	}
	return string(body)
}
ToJSON response structure to json string
package model
import (
	"encoding/json"
)
type ResponseError struct {
	ResponseInterface `json:"-"`
	Errors            interface{} `json:"errors"`
	Detail            string      `json:"detail"`
}