feat: authentication for WebUI (#62)

internal/api/authenticationhandler.go

@@ -0,0 +1,51 @@
+package api
+
+import (
+	"context"
+
+	"connectrpc.com/connect"
+	"github.com/garethgeorge/backrest/gen/go/types"
+	v1 "github.com/garethgeorge/backrest/gen/go/v1"
+	"github.com/garethgeorge/backrest/gen/go/v1/v1connect"
+	"github.com/garethgeorge/backrest/internal/auth"
+	"go.uber.org/zap"
+)
+
+type AuthenticationHandler struct {
+	// v1connect.UnimplementedAuthenticationHandler
+	authenticator *auth.Authenticator
+}
+
+var _ v1connect.AuthenticationHandler = &AuthenticationHandler{}
+
+func NewAuthenticationHandler(authenticator *auth.Authenticator) *AuthenticationHandler {
+	return &AuthenticationHandler{
+		authenticator: authenticator,
+	}
+}
+
+func (s *AuthenticationHandler) Login(ctx context.Context, req *connect.Request[v1.LoginRequest]) (*connect.Response[v1.LoginResponse], error) {
+	zap.L().Debug("login request", zap.String("username", req.Msg.Username))
+	user, err := s.authenticator.Login(req.Msg.Username, req.Msg.Password)
+	if err != nil {
+		zap.L().Warn("failed login attempt", zap.Error(err))
+		return nil, connect.NewError(connect.CodeUnauthenticated, auth.ErrInvalidPassword)
+	}
+
+	token, err := s.authenticator.CreateJWT(user)
+	if err != nil {
+		return nil, err
+	}
+
+	return connect.NewResponse(&v1.LoginResponse{
+		Token: token,
+	}), nil
+}
+
+func (s *AuthenticationHandler) HashPassword(ctx context.Context, req *connect.Request[types.StringValue]) (*connect.Response[types.StringValue], error) {
+	hash, err := auth.CreatePassword(req.Msg.Value)
+	if err != nil {
+		return nil, err
+	}
+	return connect.NewResponse(&types.StringValue{Value: hash}), nil
+}