Only set long expiration for files in _app/immutable directory

[sfriedel]

Recently SvelteKit introduced the _app/immutable directory in the buildout. This directory contains all files that should be cached with a long TTL. Serving the whole _app/ directory with a long TTL impacts the SvelteKit update check via the updated store from $app/stores (see: https://kit.svelte.dev/docs/modules#$app-stores-updated) which relies on being able to fetch the current app version from _app/version.json.

This PR splits the handlers for _app/ and _app/immutable and only sets the 30d expiration on the _app/immutable handler. Other assets in _app/ are then served with the default expiration which can further be customized by setting default_expiration in the top-level app.yaml.

Similar changes in the default adapters were introduced in sveltejs/kit#5051

[HalfdanJ]

With #28 merged, can you try and rebase / merge to master. Also, integration test needs to be updated to contain the new expected yaml in /tests/expected_app.yaml. Try running npm run test:integration

[sfriedel]

HI @HalfdanJ and sorry I completely missed the notifications on the PRs. I see you already merged the other one. I'll rebase this one and update the integration tests.

[sfriedel]

@HalfdanJ I updated /tests/expected_app.yaml. The integration tests are still failing but that seems unrelated to the changes in this branch because it also happens in main. I opened #32 which seems to be the root cause for the integration tests failures.

[HalfdanJ]

Thanks @sfriedel !