OpenFoodFacts-mcp

import { ListRootsRequestSchema } from "@modelcontextprotocol/sdk/types.js"; import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js"; import { logger } from "../transport/transports.js"; /** * Represents a root URI that defines a boundary where the server can operate */ export interface Root { uri: string; name?: string; } /** * Singleton class to store and manage root URIs */ class RootsRegistry { // The current roots provided by the client private currentRoots: Root[] = []; /** * Update the known roots with new ones from the client * * @param roots The new roots to set */ public updateRoots(roots: Root[]) { logger.info(`Updating roots: ${JSON.stringify(roots, null, 2)}`); this.currentRoots = roots; } /** * Get all current roots * * @returns The current roots */ public getRoots(): Root[] { return [...this.currentRoots]; } /** * Check if a URI is within any of the current roots * * @param uri The URI to check * @returns True if the URI is within at least one root */ public isWithinRoots(uri: string): boolean { if (this.currentRoots.length === 0) { // If no roots are defined, allow access to all resources return true; } return this.currentRoots.some(root => uri.startsWith(root.uri)); } /** * Get the most specific root that contains a URI * * @param uri The URI to check * @returns The most specific root that contains the URI, or undefined if none */ public getRootForURI(uri: string): Root | undefined { if (this.currentRoots.length === 0) { return undefined; } // Sort roots by length (descending) to find the most specific match const matchingRoots = this.currentRoots .filter(root => uri.startsWith(root.uri)) .sort((a, b) => b.uri.length - a.uri.length); return matchingRoots[0]; } } // Create a singleton instance export const rootsRegistry = new RootsRegistry(); /** * Setup roots handling for the server * * @param server The MCP server instance */ export function setupRoots(server: McpServer) { // Handler for roots/update request server.server.setRequestHandler(ListRootsRequestSchema, async (request) => { // Extract roots from the actual property in the request const rootItems = request.params?.items || []; // Ensure items conform to Root[] type const roots: Root[] = Array.isArray(rootItems) ? rootItems.map(item => ({ uri: item.uri || '', name: item.name })) : []; rootsRegistry.updateRoots(roots); return { // No response body needed }; }); logger.info("Roots capability initialized"); }