SPA mode

[Rich-Harris]

Closes #754.

With this, we can specify a fallback page when using adapter-static. This page contains no content, but will load the SvelteKit app and invoke the router, making it suitable as a 200.html with e.g. Surge, or an index.html with sirv with opts.single.

If a fallback is specified, adapter-static won't forcibly prerender every page, just the ones with prerender = true.

I added a test suite to adapter-static.

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[benmccann]

Going to make lots of people super happy! Big announcement for the Summit 😄

Do you think it's worth filing an issue about force disabling SSR as well? #754 (comment)

[benmccann]

it could be worth adding a comment here explaining why we need to use CommonJS with an ESM wrapper

[Rich-Harris]

I realised there's actually no benefit to this file — removed

[SOVLOOKUP]

#1183 this change can make test work in windows

[Rich-Harris]

Do you think it's worth filing an issue about force disabling SSR as well?

I'd rather wait for that to come up organically — I would rather we investigate alternatives (like static analysis) before providing an 'eject' button that is likely to be misused. People will just forcibly disable SSR as soon as they run into the smallest SSR problem if the option is available to them, rather than working through the problem and preserving SSR-ability where possible. That would be bad stewardship on our part.

[benmccann]

Why did this file need to be renamed to .cjs?

[ivoreis]

So it can be required by the config file https://github.com/sveltejs/kit/pull/1181/files#diff-ffa86c05d95319420b7940aecaf8b3f028dad6acf5e1ed7005b0955b01325801 / https://github.com/sveltejs/kit/pull/1181/files#diff-46bfbc5b8cd21784f755621d040007b8c28047b8d1c13dbb304555fbcec53d00

[btakita]

I have a requirement package an app using the file:// protocol, meaning there is no web server. I would love svelte kit to have SSR-less SPA capability. I could use Routify & Sapper but would rather use Svelte Kit to have both a PWA & a file:// based SPA.

[benmccann]

@btakita the issue to track that is #907