Cache bust

The following pattern is often used in templates to handle asset cache busting, with the cacheBust variable assigned at the top of the Master template.

Date is changed following occasional changes, or isDev is set true to effectively disable cache during template development.

{% assign cacheBust = '?v=YYMMDDa' %}
{% assign isDev = false %}
{% if querystring.preview or isDev %}
	{% assign cacheBust = 'now' | date: '%s' | prepend: '?v=' %}
{% endif %}

...

{{ 'style.css' | append: cacheBust | asset_url | stylesheet_tag }}
{{ 'scripts.js' | append: cacheBust | asset_url | script_tag }}