Serverless MCP

import createHttpError from 'http-errors'; import { cognitoIdentityProvider, createMiddlewareLambdaFunctionURLHandler, dynamoDB, getCognitoIdentityProviderFromContext, getLambdaFunctionURLContext, lambdaFunctionURLHandler, MiddlewareLambdaFunctionURLHandler, } from '#middleware'; import { Client } from '#model'; import { createJsonResponse } from '#utils'; import { unique } from 'remeda'; export type RegisterClientRequest = { redirect_uris: string[]; client_name: string; scope: string; }; export type RegisterClientResponse = { client_id: string; client_secret: string; client_id_issued_at: number; client_secret_expires_at: number; redirect_uris: string[]; grant_types: string[]; token_endpoint_auth_method: string; response_types: string[]; client_name: string; scope: string; }; export const baseHandler: MiddlewareLambdaFunctionURLHandler = async ( event, context ) => { const { getBodyFromEvent } = getLambdaFunctionURLContext(context); const client = getBodyFromEvent<RegisterClientRequest>(event); const { client_name, redirect_uris, scope } = client; // Validate required fields if ( !redirect_uris || !Array.isArray(redirect_uris) || redirect_uris.length === 0 ) { return createJsonResponse(400, { error: 'invalid_redirect_uri', error_description: 'redirect_uris is required and must be an array', }); } // Determine client name const clientName = client_name || `dcr-client-${Date.now()}`; const { createClient } = getCognitoIdentityProviderFromContext(context); // Create client in Cognito const { UserPoolClient } = await createClient(clientName, redirect_uris); if (!UserPoolClient || UserPoolClient?.ClientId === undefined) { throw new createHttpError.InternalServerError( 'Error creating client registration' ); } // Construct client registration response const registrationResponse: RegisterClientResponse = { client_id: UserPoolClient?.ClientId, client_secret: UserPoolClient?.ClientSecret ?? '', client_id_issued_at: Math.floor(Date.now() / 1000), client_secret_expires_at: 0, // Never expires redirect_uris, grant_types: ['authorization_code', 'refresh_token'], token_endpoint_auth_method: 'client_secret_basic', response_types: ['code'], client_name: clientName, scope: unique([ ...(scope?.split(' ') ?? []), ...(UserPoolClient?.AllowedOAuthScopes ?? []), ]).join(' '), }; await Client.create( context, UserPoolClient.ClientId, JSON.stringify(registrationResponse), JSON.stringify(client) ); // Return successful response return createJsonResponse<RegisterClientResponse>(201, registrationResponse); }; export const handler = createMiddlewareLambdaFunctionURLHandler(baseHandler) .use(lambdaFunctionURLHandler({ methods: ['POST'], urlPattern: '/clients' })) .use(cognitoIdentityProvider()) .use(dynamoDB());