Filesystem MCP Server

import { logger } from '../logger.js'; import type { Server } from '@modelcontextprotocol/sdk/server/index.js'; import type { Root } from '@modelcontextprotocol/sdk/types.js'; import { CallToolRequestSchema, ListToolsRequestSchema, RootsListChangedNotificationSchema } from '@modelcontextprotocol/sdk/types.js'; import { setAllowedDirectories } from '../lib.js'; import { getValidRootDirectories } from '../roots-utils.js'; import type { HandlerFunction } from './types.js'; import * as read from './read.js'; import * as write from './write.js'; import * as file from './file.js'; import * as list from './list.js'; import * as search from './search.js'; import * as info from './info.js'; import * as compare from './compare.js'; import * as utility from './utility.js'; import * as git from './git.js'; import * as validate from './validate.js'; const allTools = [...read.tools, ...write.tools, ...file.tools, ...list.tools, ...search.tools, ...info.tools, ...compare.tools, ...utility.tools, ...git.tools, ...validate.tools]; export function installHandlers(server: Server, allowedDirectories: string[]) { setAllowedDirectories(allowedDirectories); server.setRequestHandler(ListToolsRequestSchema, async () => ({ tools: allTools })); const handlerMap: Record<string, HandlerFunction> = { ...read.handlers, ...write.handlers, ...file.handlers, ...list.handlers, ...search.handlers, ...info.handlers, ...compare.handlers, ...utility.handlers, ...git.handlers, ...validate.handlers, }; const rateLimit = new Map<string, { count: number; resetTime: number }>(); const RATE_LIMIT_WINDOW = 60 * 1000; // 1 minute const RATE_LIMIT_MAX = 100; // requests per window server.setRequestHandler(CallToolRequestSchema, async (request) => { try { const params = request.params as { name: string; arguments?: Record<string, unknown> }; const { name, arguments: args = {} } = params; const now = Date.now(); // Rate limiting const key = `tool_${name}`; const current = rateLimit.get(key); if (current) { if (now > current.resetTime) { current.count = 1; current.resetTime = now + RATE_LIMIT_WINDOW; } else if (current.count >= RATE_LIMIT_MAX) { logger.warn(`Rate limit exceeded for tool: ${name}`); return { content: [{ type: 'text', text: 'Rate limit exceeded. Please try again later.' }], isError: true }; } else { current.count++; } } else { rateLimit.set(key, { count: 1, resetTime: now + RATE_LIMIT_WINDOW }); } // Audit logging logger.info(`Audit: Tool ${name} called with args: ${JSON.stringify(args)}`); const fn = handlerMap[name]; if (!fn) throw new Error(`Unknown tool: ${name}`); const result = await fn(args); return result as { content: Array<{ type: string; text?: string }>; isError?: boolean }; } catch (error) { const errorMessage = error instanceof Error ? error.message : String(error); return { content: [{ type: 'text', text: `Error: ${errorMessage}` }], isError: true }; } }); async function updateAllowedDirectoriesFromRoots(requestedRoots: Root[]) { const validatedRootDirs = await getValidRootDirectories(requestedRoots); if (validatedRootDirs.length > 0) { allowedDirectories = [...validatedRootDirs]; setAllowedDirectories(allowedDirectories); logger.info(`Updated allowed directories from MCP roots: ${validatedRootDirs.length} valid directories`); } else { logger.warn('No valid root directories provided by client'); } } server.setNotificationHandler(RootsListChangedNotificationSchema, async () => { try { const response = await server.listRoots(); if (response && 'roots' in response) await updateAllowedDirectoriesFromRoots(response.roots); } catch (error) { logger.error(`Failed to request roots from client: ${error instanceof Error ? error.message : String(error)}`); } }); server.oninitialized = async () => { const clientCapabilities = server.getClientCapabilities(); if (clientCapabilities?.roots) { try { const response = await server.listRoots(); if (response && 'roots' in response) await updateAllowedDirectoriesFromRoots(response.roots); else logger.warn('Client returned no roots set, keeping current settings'); } catch (error) { logger.error(`Failed to request initial roots from client: ${error instanceof Error ? error.message : String(error)}`); } } else { if (allowedDirectories.length > 0) { logger.info(`Client does not support MCP Roots, using allowed directories set from server args: ${allowedDirectories.join(', ')}`); } else { throw new Error('Server cannot operate: No allowed directories available.'); } } }; }