add

trading_assistant_api/common/auth/jwt.go

@@ -0,0 +1,49 @@
+package auth
+
+import (
+	"errors"
+	"time"
+
+	"common/utils"
+	"github.com/golang-jwt/jwt/v5"
+)
+
+func GenerateToken(userID string) (string, error) {
+	secret := utils.GetEnv("JWT_SECRET", "")
+	if secret == "" {
+		return "", errors.New("jwt_secret_missing")
+	}
+	ttlStr := utils.GetEnv("JWT_TTL", "24h")
+	ttl, err := time.ParseDuration(ttlStr)
+	if err != nil {
+		return "", err
+	}
+	issuer := utils.GetEnv("JWT_ISSUER", "trading-assistant")
+	now := time.Now()
+	claims := jwt.RegisteredClaims{
+		Subject:   userID,
+		Issuer:    issuer,
+		IssuedAt:  jwt.NewNumericDate(now),
+		ExpiresAt: jwt.NewNumericDate(now.Add(ttl)),
+	}
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+	return token.SignedString([]byte(secret))
+}
+
+func ParseToken(tokenStr string) (string, error) {
+	secret := utils.GetEnv("JWT_SECRET", "")
+	if secret == "" {
+		return "", errors.New("jwt_secret_missing")
+	}
+	var claims jwt.RegisteredClaims
+	tkn, err := jwt.ParseWithClaims(tokenStr, &claims, func(token *jwt.Token) (interface{}, error) {
+		return []byte(secret), nil
+	})
+	if err != nil {
+		return "", err
+	}
+	if !tkn.Valid {
+		return "", errors.New("token_invalid")
+	}
+	return claims.Subject, nil
+}

trading_assistant_api/common/go.mod

@@ -3,3 +3,4 @@ module common
 go 1.25.7
 
 require github.com/jackc/pgx/v5 v5.6.0
+require github.com/golang-jwt/jwt/v5 v5.2.1