Context Manager MCP Server

import { EventEmitter } from 'events'; import { Transport } from '../transport/socket-transport.js'; import { ServerCapabilities, ServerInfo, InitializeParams, InitializeResult } from './protocol-types.js'; export interface Session { id: string; transport: Transport; initialized: boolean; capabilities: InitializeParams['capabilities']; } export class SessionManager extends EventEmitter { private sessions: Map<string, Session> = new Map(); private sessionCounter: number = 0; constructor( private serverInfo: ServerInfo, private serverCapabilities: ServerCapabilities ) { super(); } public createSession(transport: Transport): Session { const sessionId = this.generateSessionId(); const session: Session = { id: sessionId, transport, initialized: false, capabilities: {} }; this.sessions.set(sessionId, session); this.emit('session:created', session); return session; } public async initializeSession( sessionId: string, params: InitializeParams ): Promise<InitializeResult> { const session = this.sessions.get(sessionId); if (!session) { throw new Error(`Session ${sessionId} not found`); } if (session.initialized) { throw new Error('Session already initialized'); } // Store client capabilities session.capabilities = params.capabilities || {}; session.initialized = true; // Filter capabilities based on client requirements const filteredCapabilities: ServerCapabilities = { tools: params.capabilities?.tools ? this.serverCapabilities.tools : undefined, resources: params.capabilities?.resources ? this.serverCapabilities.resources : undefined }; const result: InitializeResult = { capabilities: filteredCapabilities, serverInfo: this.serverInfo }; this.emit('session:initialized', session); return result; } public getSession(sessionId: string): Session | undefined { return this.sessions.get(sessionId); } public removeSession(sessionId: string): void { const session = this.sessions.get(sessionId); if (session) { this.sessions.delete(sessionId); this.emit('session:closed', session); } } public getAllSessions(): Session[] { return Array.from(this.sessions.values()); } public isInitialized(sessionId: string): boolean { const session = this.sessions.get(sessionId); return session ? session.initialized : false; } private generateSessionId(): string { return `session-${++this.sessionCounter}`; } public async shutdown(): Promise<void> { // Close all active sessions const sessions = Array.from(this.sessions.values()); await Promise.all( sessions.map(async (session) => { try { await session.transport.close(); this.removeSession(session.id); } catch (error) { this.emit('error', error); } }) ); } }