Clarifying the difference between experimental and preview docs for c… (

#6149)

* Clarifying the difference between experimental and preview docs for contributors.

* Adding a guide for Astro experimental support.

* Update src/frameworks/docs/astro.md per Austin's suggestion.

Co-authored-by: Austin Crim <aust.crim@gmail.com>

* Update src/frameworks/docs/astro.md per suggestion.

Co-authored-by: Austin Crim <aust.crim@gmail.com>

---------

Co-authored-by: Austin Crim <aust.crim@gmail.com>

src/frameworks/docs/README.md

@@ -1,13 +1,27 @@
 # Web frameworks docs on firebase.google.com
 
-This directory contains the source of the Web frameworks documentation on
-https://firebase.google.com/docs/.
+This directory contains the documentation
+for experimental framework support as well as source that is used for
+preview-level support on https://firebase.google.com/docs/.
 
 We welcome your contributions! See [`CONTRIBUTING.md`](../CONTRIBUTING.md) for general
-guidelines.
+guidelines. This README has some information on how our documentation is organized and
+some non-standard extensions we use.
+
+## Docs for preview-level vs experimental framework support
+
+If you are developing **experimental** support for a web framework, you should
+follow the outline and example presented in `astro.md`. Details for your framework are
+likely to be different, but the overall outline should probably be similar.
+
+If your framwork is entering **preview** status, its documentation will be displayed
+on firebase.google.com, which may entail some extra work regarding page fragments
+(see next section). Preview docs should follow the outline and example presented in
+`angular.md`. Make sure to add all key details specific to your particular framework.
+
+Firebase follows the [Google developer documentation style guide](https://developers.google.com/style),
+which you should read before writing substantial contributions.
 
-This file has some information on how our documentation is organized and some
-non-standard extensions we use.
 
 ## Standalone files vs. page fragments
 
@@ -60,16 +74,6 @@ These are non-standard metadata declarations used by our internal publishing
 system. There's nothing you can really do with this, but it has to be on every
 standalone page.
 
-### Getting started writing
-
-Unless the needs of your framework are radically different, you should
-follow the outline and example presented in `angular.md`, which to date is
-the most completely fleshed-out integration. Details for your framework are
-likely to be different, but the overall outline should probably be similar.
-
-Firebase follows the [Google developer documentation style guide](https://developers.google.com/style),
-which you should read before writing substantial contributions.
-
 Footer
 © 2023 GitHub, Inc.
 Footer navigation

src/frameworks/docs/astro.md

@@ -0,0 +1,76 @@
+# Integrate Astro
+
+Using the {{firebase_cli}}, you can deploy your Astro Web apps to Firebase and
+serve them with {{firebase_hosting}}. The {{cli}} respects your Astro settings and
+translates them to Firebase settings with zero or minimal extra configuration on
+your part. If your app includes dynamic server-side logic, the {{cli}} deploys that
+logic to {{cloud_functions_full}}.
+
+Note: Framework-aware {{hosting}} is an early public preview. This means
+that the functionality might change in backward-incompatible ways. A preview
+release is not subject to any SLA or deprecation policy and may receive limited
+or no support.
+
+## Before you begin
+
+Before you get started deploying your app to Firebase,
+review the following requirements and options:
+
+- {{firebase_cli}} version 12.1.0 or later. Make sure to
+  [install the {{cli}}](/docs/cli#install_the_firebase_cli)
+  using your preferred method.
+- Optional: Billing enabled on your Firebase project
+  (required if you plan to use SSR)
+- An existing Astro project. You can create one with `npm init astro@latest`.
+
+
+## Initialize Firebase
+
+To get started, initialize Firebase for your framework project.
+Use the {{firebase_cli}} for a new project, or modify `firebase.json` for an
+existing project.
+
+### Initialize a new project
+
+1. In the {{firebase_cli}}, enable the web frameworks preview:
+   <pre class="devsite-terminal">firebase experiments:enable webframeworks</pre>
+1. Run the initialization command from the {{cli}} and then follow the prompts:
+   <pre class="devsite-terminal">firebase init hosting</pre>
+1.  Answer yes to "Do you want to use a web framework? (experimental)"
+1.  Choose your hosting source directory.  If there is an existing Astro codebase,
+    the CLI detects it and the process completes.
+
+## Serve static content
+
+After initializing Firebase, you can serve static content with the standard
+deployment command:
+
+```shell
+firebase deploy
+```
+
+You can [view your deployed app](/docs/hosting/test-preview-deploy#view-changes)
+on its live site.
+
+## Pre-render dynamic content
+
+Astro will prerender all pages to static files and will work on Firebase Hosting without any configuration changes.
+
+If you need a small set of pages to SSR, configure `output: 'hybrid'` as
+shown in
+[converting a static site to hybrid rendering](https://docs.astro.build/en/guides/server-side-rendering/#converting-a-static-site-to-hybrid-rendering`).
+
+With these settings prerendering is still the default, but you can opt in to SSR by
+adding `const prerender = false` at the top of any Astro page. Similarly, in `output: 'server'` where
+server rendering is the default you can opt in to prerendering by adding 
+`const prerender = true`.
+
+## Serve fully dynamic content (SSR)
+
+Deploying an Astro application with SSR on Firebase Hosting requires the 
+@astrojs/node adapter in middleware mode. See the detailed instructions in the
+Astro docs for setting up the
+[node adapter](https://docs.astro.build/en/guides/integrations-guide/node/)
+and for [SSR](https://docs.astro.build/en/guides/server-side-rendering/).
+
+As noted in the Astro guidance, SSR also requires setting the `output` property to either `server` or `hybrid` in `astro.config.mjs`.