adding an MCP Server 🎉

mcp/mcpAuthentication.js

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+/*
+ * Copyright (c) 2026 by Christian Kellner.
+ * Licensed under Apache-2.0 with Commons Clause and Attribution/Naming Clause
+ */
+
+/**
+ * MCP Authentication Layer
+ *
+ * Centralizes all authentication and authorization logic for MCP tool calls
+ * and HTTP requests. Ensures consistent access control across all transports.
+ */
+
+import { getUser, validateMcpToken } from '../lib/services/storage/userStorage.js';
+
+/**
+ * Authenticate an MCP tool call by extracting and validating the user from authInfo.
+ *
+ * @param {{ authInfo?: { userId?: string } }} extra - The extra context passed by the MCP SDK.
+ * @returns {{ user: object|null, error: string|null }}
+ *   - On success: { user: <userObject>, error: null }
+ *   - On failure: { user: null, error: <errorMessage> }
+ */
+export function authenticateToolCall(extra) {
+  const userId = extra?.authInfo?.userId;
+  if (!userId) {
+    return { user: null, error: 'Authentication required. Please provide a valid MCP API token.' };
+  }
+
+  const user = getUser(userId);
+  if (!user) {
+    return { user: null, error: 'Authentication required. Please provide a valid MCP API token.' };
+  }
+
+  return { user, error: null };
+}
+
+/**
+ * Check whether a user has access to a specific job.
+ * Admins have access to all jobs. Non-admins can only access their own jobs
+ * or jobs explicitly shared with them.
+ *
+ * @param {object} user - The authenticated user object.
+ * @param {object} job - The job object from storage.
+ * @returns {boolean} True if the user is allowed to access this job.
+ */
+export function checkJobAccess(user, job) {
+  if (user.isAdmin) return true;
+  if (job.userId === user.id) return true;
+  if (Array.isArray(job.shared_with_user) && job.shared_with_user.includes(user.id)) return true;
+  return false;
+}
+
+/**
+ * Authenticate an HTTP request by extracting and validating the Bearer token
+ * from the Authorization header.
+ *
+ * @param {import('http').IncomingMessage} req
+ * @returns {{ userId: string } | null} The authenticated user info, or null if invalid.
+ */
+export function authenticateRequest(req) {
+  const authHeader = req.headers['authorization'] || '';
+  if (!authHeader.startsWith('Bearer ')) return null;
+  const token = authHeader.slice(7).trim();
+  if (!token) return null;
+  return validateMcpToken(token);
+}