refactor(api): API overhaul (#392)

api/jwt/jwt.go

@@ -0,0 +1,66 @@
+package jwt
+
+import (
+	"github.com/portainer/portainer"
+
+	"fmt"
+	"github.com/dgrijalva/jwt-go"
+	"github.com/gorilla/securecookie"
+	"time"
+)
+
+// Service represents a service for managing JWT tokens.
+type Service struct {
+	secret []byte
+}
+
+type claims struct {
+	Username string `json:"username"`
+	jwt.StandardClaims
+}
+
+// NewService initializes a new service. It will generate a random key that will be used to sign JWT tokens.
+func NewService() (*Service, error) {
+	secret := securecookie.GenerateRandomKey(32)
+	if secret == nil {
+		return nil, portainer.ErrSecretGeneration
+	}
+	service := &Service{
+		secret,
+	}
+	return service, nil
+}
+
+// GenerateToken generates a new JWT token.
+func (service *Service) GenerateToken(data *portainer.TokenData) (string, error) {
+	expireToken := time.Now().Add(time.Hour * 8).Unix()
+	cl := claims{
+		data.Username,
+		jwt.StandardClaims{
+			ExpiresAt: expireToken,
+		},
+	}
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, cl)
+
+	signedToken, err := token.SignedString(service.secret)
+	if err != nil {
+		return "", err
+	}
+
+	return signedToken, nil
+}
+
+// VerifyToken parses a JWT token and verify its validity. It returns an error if token is invalid.
+func (service *Service) VerifyToken(token string) error {
+	parsedToken, err := jwt.Parse(token, func(token *jwt.Token) (interface{}, error) {
+		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
+			msg := fmt.Errorf("Unexpected signing method: %v", token.Header["alg"])
+			return nil, msg
+		}
+		return service.secret, nil
+	})
+	if err != nil || parsedToken == nil || !parsedToken.Valid {
+		return portainer.ErrInvalidJWTToken
+	}
+	return nil
+}