Serverless MCP

import createError from 'http-errors'; import { createMiddlewareLambdaFunctionURLHandler, getLambdaFunctionURLContext, getProcessEnv, lambdaFunctionURLHandler, MiddlewareLambdaFunctionURLHandler, } from '#middleware'; import { logger } from '#powertools'; export type MetadataResponse = { resource: string; authorization_servers: string[]; scopes_supported: string[]; bearer_methods_supported: string[]; }; export const baseHandler: MiddlewareLambdaFunctionURLHandler = async ( event, context ): Promise<{ statusCode: number; headers: Record<string, string> }> => { const { method } = getLambdaFunctionURLContext(context); switch (method) { case 'OPTIONS': return { statusCode: 204, headers: { 'Content-Type': 'application/json' }, }; case 'GET': const region = getProcessEnv('AWS_REGION', 'no aws region given'); const userPoolId = getProcessEnv('USER_POOL_ID', 'no user pool id given'); const response = await fetch( `https://cognito-idp.${region}.amazonaws.com/${userPoolId}/.well-known/openid-configuration` ); const { authorization_endpoint } = await response.json(); const params = event.queryStringParameters ?? {}; delete params.scope; const authorizationUrl = `${authorization_endpoint}?${new URLSearchParams(params as Record<string, string>).toString()}`; logger.info('oauth authorization url', { authorizationUrl }); return { statusCode: 302, headers: { Location: authorizationUrl }, }; default: throw new createError.MethodNotAllowed(); } }; export const handler = createMiddlewareLambdaFunctionURLHandler( baseHandler ).use( lambdaFunctionURLHandler({ methods: ['GET'], urlPattern: '/oauth/authorize', }) );