Glean MCP Server

/** * @fileoverview Glean client implementation using the Glean API client. * * This module provides a client for interacting with the Glean API. * * Required environment variables: * - GLEAN_INSTANCE or GLEAN_SUBDOMAIN: Name of the Glean instance * - GLEAN_API_TOKEN: API token for authentication * * Optional environment variables: * - GLEAN_ACT_AS: User to impersonate (only valid with global tokens) * * @module common/client */ import { HTTPClient } from '@gleanwork/api-client/lib/http.js'; import { VERSION } from './version.js'; import { getConfig, isGleanTokenConfig, sanitizeConfig, } from '@gleanwork/mcp-server-utils/config'; import { trace } from '@gleanwork/mcp-server-utils/logger'; import { Glean, SDK_METADATA, SDKOptions } from '@gleanwork/api-client'; import { Client } from '@gleanwork/api-client/sdk/client.js'; let clientInstancePromise: Promise<Client> | null = null; const USER_AGENT = `speakeasy-sdk/typescript ${VERSION} ${SDK_METADATA.genVersion} ${SDK_METADATA.openapiDocVersion} @gleanwork/local-mcp-server`; /** * Gets the singleton instance of the Glean client, creating it if necessary. * * @returns {Promise<Client>} The configured Glean client instance * @throws {Error} If required environment variables are missing */ export async function getClient(): Promise<Client> { if (!clientInstancePromise) { clientInstancePromise = (async () => { const glean = new Glean(await getAPIClientOptions()); return glean.client; })(); } return clientInstancePromise; } function buildHttpClientWithGlobalHeaders( headers: Record<string, string>, ): HTTPClient { const httpClient = new HTTPClient(); httpClient.addHook('beforeRequest', (request) => { const nextRequest = new Request(request, { signal: request.signal || AbortSignal.timeout(5000), }); for (const [key, value] of Object.entries(headers)) { nextRequest.headers.set(key, value); } return nextRequest; }); return httpClient; } export async function getAPIClientOptions(): Promise<SDKOptions> { const config = await getConfig(); const opts: SDKOptions = {}; opts.serverURL = config.baseUrl; trace('initializing client', opts.serverURL); if (isGleanTokenConfig(config)) { opts.apiToken = config.token; const { actAs } = config; if (actAs) { opts.httpClient = buildHttpClientWithGlobalHeaders({ 'X-Glean-ActAs': actAs, 'user-agent': USER_AGENT, }); } } else { trace( 'No API token provided. Requests will be made without authentication.', sanitizeConfig(config), ); // Continue without authentication - let the API reject if needed opts.httpClient = buildHttpClientWithGlobalHeaders({ 'user-agent': USER_AGENT, }); } return opts; } /** * Resets the client instance. Useful for testing or reconfiguration. */ export function resetClient(): void { clientInstancePromise = null; }