Preview changes

A saved change is a draft in Mica. The website shows it after Publish, when the host builds the site again. There are three ways to see a change before or right after that.

Open the page on the website

Give a collection or a singleton the address of its page, and give Mica the address of the website:

news: collection({ label: "News", url: "/news/{slug}", fields: { … } }),
about: singleton({ label: "About", url: "/about", fields: { … } }),

Set MICA_SITE_URL to the website's address, such as https://example.com. Then an entry shows "Open on website" beside Save, and the Publish page links to each page that it published. A new entry gets the link after its first Publish, because its page does not exist before.

The link opens the published page. After a Publish, the host needs a few minutes to build it.

Preview with the local editor

Run astro dev beside the local editor. The dev server reads the saved drafts, so it shows a change as soon as you save it, before Publish. With a url in the model, an entry shows "Preview" beside Save while the dev server runs, also a new entry. Added in 0.11.0.

The local editor finds the dev server at the port and the base path of the Astro config, http://localhost:4321 by default. If Astro takes another port because that one is busy, set server.port in astro.config. The self-hosted Mica has no preview.

Use a staging site

For a check before the real website changes, run a second Mica on a staging branch:

1. Make a branch, such as staging, and let the host build it as a second site.
2. Start a second self-hosted Mica with MICA_REPOSITORY_BRANCH=staging.
3. Editors publish there and check the staging site.
4. A developer merges staging into main when the changes are ready.

The deploy previews of hosts such as Netlify, Vercel and Cloudflare Pages build branches and pull requests. They show published changes on a branch. They cannot show drafts, because a draft is not on any branch.