Add a config option for filenames generated by the @astrojs/sitemap integration

[mattyoho]

Changes

This adds a configuration option for the @astrojs/sitemap integration for setting the base filename for the generated sitemap XML files.

Impact on existing users

The new configuration setting is defaulted to a value that matches current behavior so that existing users won't be impacted.

Use case

Scenario: Astro is chosen for adding informational content pages for an existing product website at a set of top-level content categories, e.g., Docs, Blog, and Changelog. The content verticals need to be hosted on the root domain at /docs, /blog, and /changelog, respectively.

E.g., the Docs URL will be https://example.com/docs.

Problem: Currently, the generated sitemap files want to live at https://example.com/sitemap-index.xml and https://example.com/sitemap-{n}.xml, which will potentially conflict with an existing sitemap.xml for the root domain.

Solution: Add a config setting to change the generated filename so that the files can be integrated into a pre-existing sitemap-index.xml via other external tooling.

// https://astro.build/config
export default defineConfig({
  site: "https://example.com",
  integrations: [
    sitemap({
      filenameBase: "content-sitemap",
    }),
  ],
});

Testing

A test was added to the relevant test file. The change was also tested in a live Astro app using a local build of the integration package.

Docs

Documentation for the setting could / should be added to the related guide. Initial suggested changes PR has been opened here: withastro/docs#11614.

/cc @withastro/maintainers-docs for feedback!

[changeset-bot]

🦋 Changeset detected

Latest commit: d0cb2a6

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[ematipico]

The feature seems reasonable, simple enough and easy to understand. Thank you also for sending a PR to docs. I will ask docs to review the docs PR, in the meantime can you review the changeset?

[ematipico]

Changesets are meant to document and show new features. In your case, you want to explicitly discuss the new feature you're adding, why it was added, and how users can use it (code snippet). It's a minimal version of the docs.

[mattyoho]

Thanks for the feedback, @ematipico. 🙂 I gave it a try in d0cb2a6, and will be happy to incorporate further review!