Subscribe users to multiple ESP mailing lists using the JavaScript below:
var email = ::EMAIL::;
var API_URL = ::API_URL::;
var SITE_ID = ::SITE_ID::;
var MAILING_LISTS = [ ::MAILING_LISTS:: ];
var body = {email: email, sqids: MAILING_LISTS};
var xhr = new XMLHttpRequest();
xhr.open('POST', API_URL + '/tracker/lucid/sub/' + SITE_ID, true);
xhr.setRequestHeader('Content-type', 'application/json');
xhr.send(JSON.stringify(body));
Fill in the following values:
::EMAIL:: - the user's email
::API_URL:: - the API base URL for your ESP environment, for example //api-esp.piano.io or //sandbox-api-esp.piano.io.
::SITE_ID:: - your Site ID in ESP
::MAILING_LISTS:: - an array of Mailing list IDs
Add this script to your Offer template using the <div custom-script> method. Use it to create a template where subscribers select and join multiple newsletters. You can deploy that offer template in any Composer Experience.
Alternatively, create a built-in ESP opt-in form and configure groups of mailing lists for your audience. Then use the Show newsletter signup action card in Composer to display the form. More information is available here.