Provide generated sidebar entries to custom pages

[KianNH]

What version of starlight are you using?

0.25.2

What is your idea?

Provide generated sidebar entries, like how Astro.props.sidebar functions on overridden components, to custom pages (or more?).

Why is this feature necessary?

When using the StarlightPage component, you can pass a sidebar prop with entries but have no way of grabbing the current entries to filter or append to.

It was an use-case from the Discord to append entries to the sidebar, i.e blog posts on a /src/pages/blog.astro page.

Unfortunately, even if the sidebar config is imported into the custom page then the shapes differ (i.e { label: string, link: string } vs { type: "link", label: string, href: string, ... }) and won't pass validation.

Do you have examples of this feature in other projects?

No response

Participation

• I am willing to submit a pull request for this feature.

[delucis]

Thanks again for flagging this @KianNH!

@HiDeoo what do you think about supporting the same config shape for the sidebar prop as in the main Starlight config? I would guess we can still autogenerate groups if needed? It might be a breaking change, but it could simplify use cases like this where people want to share a sidebar between their main Starlight config and their custom pages. And I don’t think it prevents any current use cases?

[HiDeoo]

what do you think about supporting the same config shape for the sidebar prop as in the main Starlight config? I would guess we can still autogenerate groups if needed?

I think this is correct, and if I remember correctly and I'm not sure where, but I think we discussed some time ago this possibility as a potential improvement. This would indeed be a breaking change but mostly a shape change I think.

Noting that for the use case mentioned, this is already possible by not specifying a sidebar to <StarlightPage/> so it uses the default global sidebar, and appending entries in a <Sidebar/> override. Plugins wise, I think this would not have a lot of impact as it may still be easier for a similar behavior to also use the override approach vs grabbing the global sidebar config and passing it down to <StarlightPage/>.

When I get the time, I can try to play around with this and see if it works as we expect 👍

[delucis]

I also remember discussing this but went through the places I expected the discussion to be and couldn’t find it 😅

It’s true you can do this with overrides, but I guess for some use cases with multiple <StarlightPage> it’s more comfortable to do manually and separate out the logic for each route instead of needing to add sidebar code for each route to the override.

[HiDeoo]

Starting with Starlight v0.26.0, the <StarlightPage /> component sidebar prop to accept an array of SidebarItems like the main Starlight sidebar configuration in astro.config.mjs.

This change simplifies the definition of sidebar items in the <StarlightPage /> component, allows for shared sidebar configuration between the global sidebar option and <StarlightPage /> component, and also enables the usage of autogenerated sidebar groups with the <StarlightPage /> component.