Preview every Shopify theme pull request on a real store

A theme diff tells you which Liquid changed. It doesn't tell you what the product page looks like now, whether a section still renders, or whether the cart broke on a template nobody opened. For that, someone has to push the branch to a store, find the theme and send the link around.

Auditor does that part for you. Turn on theme previews for a repository and every reviewed pull request gets its own theme on a real store, linked from the pull request.

What reviewers see

The review's walkthrough comment, the pull request description's Preview section and a GitHub deployment named "Theme preview" all carry:

• Open preview and Open theme editor links for the pull request's theme.
• The store, the theme (always unpublished) and the commit it was built from.
• A render check, such as "3/3 pages render with no Liquid errors", across the pages you choose. It defaults to the home page, /collections/all and /cart, and you can list up to eight.
• Any files Shopify rejected, and why, when a deploy fails.
• A note when the store has a storefront password, so reviewers know they'll need it.

Later pushes update the same theme, so the link in the pull request stays the same for the whole review.

Previews that look like the store

Most theme repositories leave merchant content out of git with .shopifyignore: templates, section groups, theme settings and locales that merchants edit in the theme editor. A preview built from the branch alone would show default content and look broken.

So when the repository ignores those files, Auditor copies them from the store's published theme into the preview, reading the published theme without changing it, and says how many files it copied. The preview shows the merchant's real homepage with the pull request's code.

If you'd rather review on one shared theme, Deploy to one theme pushes every pull request to the same theme id, which is never deleted.

How it builds and deploys

Many themes have a build step for CSS or JavaScript. Auditor detects the build setup once, and you can edit it. Then:

1. The theme is built in an isolated sandbox that can reach package registries but never holds your store's credentials.
2. A second sandbox receives only the theme folders (assets, blocks, config, layout, locales, sections, snippets and templates), runs nothing from the repository and uploads the theme with the Shopify CLI.

Builds have nine minutes, deploys ten, and a theme can be up to 70 MB.

Setting it up

1. Install the Auditor GitHub app on the theme's repository.
2. Give Auditor access to the store. Either sign in to Shopify once under Add-ons → Shopify on the Auditor page, or give the repository a Theme Access password, which can only touch themes and isn't tied to a person.
3. Turn on Theme preview in the repository's settings and choose the store.

From a terminal, the Auditor CLI does the same in one line:

SHOPIFY_THEME_ACCESS_PASSWORD=shptka_… auditor preview set --store your-store.myshopify.com --enable-repo

To deploy a preview without a full review, comment @auditor preview on the pull request.

Limits and defaults

• Pull requests from forks are skipped by default.
• A repository keeps at most five preview themes at once by default, and you can change that.
• Previews are deleted when their pull request closes, unless you turn that off.
• A preview is never published.

Auditor has no seat price. Preview builds count toward the repository's cost and its monthly and per-pull-request caps like the rest of a review.