jwt.go

package auth

import (
	"encoding/json"
	"github.com/golang-jwt/jwt/v4"
	"gitlab.bob.co.za/bob-public-utils/bobgroup-go-utils/date_utils"
	"gitlab.bob.co.za/bob-public-utils/bobgroup-go-utils/errors"
	"net/http"
	"time"
)

type JsonWebToken struct {
	UserID     string    `json:"user_id"`
	Password   string    `json:"password"`
	ProviderID int64     `json:"provider_id,omitempty"`
	ExpiryDate time.Time `json:"expiry_date"`
}

// GenerateJWT takes the payload and generates a signed JWT using the provided secret
func GenerateJWT(payload JsonWebToken, secret []byte) (string, error) {
	// Convert the JsonWebToken to a map[string]interface{}
	tokenBytes, err := json.Marshal(payload)
	if err != nil {
		return "", err
	}

	tokenMap := make(map[string]interface{})
	err = json.Unmarshal(tokenBytes, &tokenMap)
	if err != nil {
		return "", err
	}

	// Create the signed token
	token := jwt.NewWithClaims(jwt.SigningMethodHS256, jwt.MapClaims(tokenMap))
	tokenString, err := token.SignedString(secret)
	if err != nil {
		return "", err
	}

	return tokenString, nil
}

// ValidateJWT parses the JWT and validates that it is signed correctly
func ValidateJWT(tokenString string, secret []byte) (JsonWebToken, error) {
	token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
		// Validate the signing method
		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
			return nil, errors.Errorf("unexpected signing method: %v", token.Header["alg"])
		}

		return secret, nil
	})
	if err != nil {
		return JsonWebToken{}, err
	}
	if token == nil {
		return JsonWebToken{}, errors.Error("could not get token from token string")
	}

	claims, ok := token.Claims.(jwt.MapClaims)
	if !ok || !token.Valid {
		return JsonWebToken{}, errors.Error("invalid token")
	}

	// Convert the MapClaims to a JsonWebToken
	claimsBytes, err := json.Marshal(claims)
	if err != nil {
		return JsonWebToken{}, err
	}