JSON & Default Filters

default — Fallback Values

The default filter returns a fallback when the left value is nil, false, or empty. Essential for metafields and optional section settings.

{{ product.metafields.custom.subtitle | default: product.title }}
{{ section.settings.heading | default: 'Welcome to our store' }}

json — Passing Data to JavaScript

The json filter serializes Liquid objects into valid JSON for embedding in <script> tags. Shopify ensures proper escaping.

<script type="application/json" id="ProductJson-{{ product.id }}">
  {{ product | json }}
</script>

1. JavaScript reads the JSON: JSON.parse(document.getElementById('ProductJson-...').textContent)
2. Use variant data to update price and image on option change
3. Never use client-side prices for checkout — always server-authoritative