Using the Shopify queue to add items to the cart

shopifyCartQueue.js

Shopify.queue = [];
  Shopify.moveAlong = function() {
    if (Shopify.queue.length) {
      var request = Shopify.queue.shift();
      Shopify.addItem(request.variantId, request.quantity, request.properties, Shopify.moveAlong);
    }
    else {
      document.location.href = '/cart';
    }
  };
  Shopify.addItem = function(id, qty, properties, callback) {
    var params = {
      quantity: qty,
      id: id
    };
    if(properties != false){
      params.properties = properties;
    }
    $.ajax({
      type: 'POST',
      url: '/cart/add.js',
      dataType: 'json',
      data: params,
      success: function(){
        if(typeof callback === 'function'){
          callback();
        }
      },
      error: function(){}
    });
  }
  function push_to_queue(variantID, quantity, properties,callback) {
    Shopify.queue.push({
      variantId: variantID,
      quantity: quantity,
      properties: properties
    });
     if(typeof callback === 'function'){
          callback();
     }
  }
  
  push_to_queue(1234, 1, {}, Shopify.moveAlong);