MCP Gateway

// Service for handling token refresh and authentication state import { fetchWithAuth } from './api'; interface TokenResponse { access_token: string; token_type: string; } class AuthService { private static refreshPromise: Promise<string | null> | null = null; /** * Refreshes the authentication token * @returns A promise that resolves to the new token or null if refresh failed */ public static async refreshToken(): Promise<string | null> { // If there's already a refresh in progress, return that promise // This prevents multiple simultaneous refresh requests if (this.refreshPromise) { return this.refreshPromise; } const token = localStorage.getItem('mcp_token'); if (!token) { return null; } // Create new promise for token refresh this.refreshPromise = (async () => { try { const response = await fetchWithAuth('/tools/refresh-token', token, { method: 'POST', }); if (!response.ok) { // If unauthorized, clear the token if (response.status === 401) { localStorage.removeItem('mcp_token'); } console.error('Error refreshing token:', response.status); return null; } const data: TokenResponse = await response.json(); const newToken = data.access_token; // Clean up the token if needed const tokenValue = newToken.startsWith('Bearer ') ? newToken.substring(7) : newToken; // Save to localStorage localStorage.setItem('mcp_token', tokenValue); return tokenValue; } catch (error) { console.error('Unexpected error during token refresh:', error); return null; } finally { // Clear the promise once done this.refreshPromise = null; } })(); return this.refreshPromise; } /** * Checks if the current token is valid or needs to be refreshed * @returns Promise<boolean> True if authenticated, false otherwise */ public static async isAuthenticated(): Promise<boolean> { const token = localStorage.getItem('mcp_token'); if (!token) { return false; } try { // Try to decode and check expiration const payloadBase64 = token.split('.')[1]; const payload = JSON.parse(atob(payloadBase64)); // If token expires in less than 5 minutes, refresh it const currentTime = Math.floor(Date.now() / 1000); if (payload.exp - currentTime < 300) { // 300 seconds = 5 minutes const newToken = await this.refreshToken(); return !!newToken; } return true; } catch (error) { console.error('Error checking token validity:', error); return false; } } } export default AuthService;