(adapter-node) Set cache header for the /static files

[hyunbinseo]

Describe the problem

The Node.js adapter sets the cache-control to the /_app/immutable files only.

kit/packages/adapter-node/src/handler.js

Lines 54 to 56 in 511126b

	if (pathname.startsWith(`/${manifest.appPath}/immutable/`) && res.statusCode === 200) {
	res.setHeader('cache-control', 'public,max-age=31536000,immutable');
	}

Files in the /static directory - which are copied to the root of the /_app directory - are not cached by the client.

Describe the proposed solution

• Provide an adapter option to set the max-age value.
• Set a default cache-control for the /static assets.

Alternatives considered

No response

Importance

nice to have

Additional Information

• Opt-out of asset inlining - with SSR support vitejs/vite#15986

[brunnerh]

Caching these by default is not a good idea because they have fixed paths so cache busting is not an option.
(Other assets automatically get a hash which makes their caching safe.)

[hyunbinseo]

@brunnerh I've crossed-out that option.

For additional context for the readers:

import background from '$lib/static/background.svg';

// Becomes /_app/immutable/assets/background.CKwt2LG5.svg

This is why imported static assets can have a cache max-age of 1yr.

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Still I do hope there was an option to enable caching manually.

The /static directory is basically useless as of now.

[Conduitry]

Duplicate of (part of) #3194.

[hyunbinseo]

My bad. I've actually 👍 one of the comments in that issue.

Note: With the cache-control header keyword, the issue is listed on the 4th page.