Map your variables

This is the heart of the migration, and where your inventory pays off. Every eVar, prop, and event you catalogued earlier now needs a home in the payload, but instead of setting them one at a time on a global object the way doPlugins did, you bundle them into a single structured object the Edge understands. The good news: thanks to the Full Extension, most slot into predictable, named places[4]. We handle them in five groups, because variables of the same kind map the same way, learn the pattern once per group and the rest is repetition.

var dl = (window.digitalData && window.digitalData.product) || [];
return (Array.isArray(dl) ? dl : [dl])
  .filter(function (p) { return p && p.sku && p.name; })
  .map(function (p) {
    return { SKU: p.sku, name: p.name, quantity: p.quantity || 1,
             priceTotal: (p.price || 0) * (p.quantity || 1) };
  });