Not sure how to connect an AJAX call to a controller and make it update a object

Question

I am very new to ajax calls and controllers, please be patient with me.
I have some client side JS that I need to add an ajax call to update a boolean to true once a button is clicked
Client Side JS:

$(document).on('click', '.add-to-cart', function(e) {
    $.ajax({
        url: url,
        type: 'post',
        data: true// but I do not know what goes here
    success:(function () {//dont know what response to put in
       //I know it handles response from server but what would I put in here to update 
    }).fail(function (err) {
        console.log({err});
    });
});

Controller:

server.post(
    'updateButtonAdded',
    function (req, res, next) {
        var addToCartButtonClicked = customer.profile.custom.AddButton;// declaring the custom attribute I want to show on a profile if the button is clicked       
        if (??) {
           // I know I need to add something here to have the logic of when the button gets clicked, set the addToCartButtonClicked = true to update to the customer profile and have it checked because I set as a boolean 
        }
    next();
    }
);

I tried to fill out what I dont understand, please assist if can, I am very confused when it comes to controllers and ajax calls. More the explanation the better for me!

Answer 1

normally what we would do, is to set the URL in the ISML, get the URL value in the JS files, then make the AJAX call. Here is an example:

ISML:

<input id="yourIdHere" type="hidden" value="${URLUtils.url('YOURCONTROLLER-updateButtonAdded')}"/>

JS:

var url =  $('#yourIdHere').val();
$.ajax({
  url: url,
  method: "GET",
  success: function (data) {
    //your success code
  },
  error: function () {
    //your error code
  },
});