mjslabs/auth-plug

package auth

import (
    "errors"
    "time"

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

// JWTCreateToken creates a JWT with the claims configured
// in the User struct and sends it back to the client.
func JWTCreateToken(u User) (string, error) {
    method, err := jwtSigningMethodFromString(Cfg.JWTMethod)
    if method == nil || err != nil {
        return "", err
    }

    token := jwt.New(method)
    claims := token.Claims.(jwt.MapClaims)
    claims["exp"] = time.Now().Add(Cfg.JWTValidMinutes).Unix()
    claims["nbf"] = time.Now().Add(time.Second * -5).Unix()
    // Grab the fields from the User struct and put them into the jwt claims
    myMap := structs.Map(u)
    for claim := range myMap {
        claims[claim] = myMap[claim]
    }

    return token.SignedString([]byte(Cfg.JWTSecret))
}

func jwtSigningMethodFromString(method string) (jwt.SigningMethod, error) {
    switch method {
    case "HS256":
        return jwt.SigningMethodHS256, nil
    case "HS384":
        return jwt.SigningMethodHS384, nil
    case "HS512":
        return jwt.SigningMethodHS512, nil
    }

    return nil, errors.New("unsupported JWT signing method")
}