verify_jwt.go

package lib

import (
	"fmt"
	"os"

	"github.com/dgrijalva/jwt-go"
)

func Verify_jwt(cookie string) (string, error) {
	token, err := jwt.Parse(cookie, func(token *jwt.Token) (interface{}, error) {
		// Don't forget to validate the alg is what you expect:
		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
			return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
		}

		return []byte(os.Getenv("JWT_SECRET")), nil
	})
	if claims, ok := token.Claims.(jwt.MapClaims); ok && token.Valid {
		return fmt.Sprint(claims["email"]), nil
	} else {
		return "", err
	}
}