server, port = options.port || process.env.PORT || 1337, endpoint = options.endpoint || process.env.MESSENGER_ENDPOINT || '/webhook', app_secret = options.app_secret || process.env.MESSENGER_APP_SECRET;
server, port = options.port || process.env.PORT || 1337, endpoint = options.endpoint || process.env.MESSENGER_ENDPOINT || '/webhook', app_secret = options.app_secret || process.env.MESSENGER_APP_SECRET;