feat(*): initial commit

internal/auth/jwt.go

@@ -0,0 +1,54 @@
+package auth
+
+import (
+	"time"
+
+	"github.com/golang-jwt/jwt/v5"
+)
+
+var signingkey []byte
+
+type JWTClaims struct {
+	User string `json:"user"`
+	jwt.RegisteredClaims
+}
+
+func SetSigningKey(key string) {
+	signingkey = []byte(key)
+}
+
+func NewJWT(user string) (string, error) {
+	claims := JWTClaims{
+		user,
+		jwt.RegisteredClaims{
+			ExpiresAt: jwt.NewNumericDate(time.Now().Add(15 * time.Minute)), // Expires in 24 hours
+			IssuedAt:  jwt.NewNumericDate(time.Now()),
+			Issuer:    "outfit-voting-abi26",
+		},
+	}
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+
+	return token.SignedString(signingkey)
+}
+
+func ValidateJWT(token string) (string, error) {
+	claims := &JWTClaims{}
+	parsed, err := jwt.ParseWithClaims(token, claims, func(t *jwt.Token) (any, error) {
+		if _, ok := t.Method.(*jwt.SigningMethodHMAC); !ok {
+			return nil, jwt.ErrSignatureInvalid
+		}
+		return signingkey, nil
+	})
+
+	if err != nil {
+		return "", err
+	}
+
+	claims, ok := parsed.Claims.(*JWTClaims)
+
+	if !ok {
+		return "", jwt.ErrTokenInvalidClaims
+	}
+
+	return claims.User, nil
+}