fix: dynamic import assets in inline worker

[proc07]

fix #17825

After using inline, the code will be converted to base64 encoding, so that the relative path in the worker file cannot get the corresponding actual file path

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[hi-ogawa]

This approach might have an issue with relative base. I'm checking pnpm -C playground/worker build:relative-base + preview:relative-base and I see this code in the inline worker:

import(self.location.origin + "./worker-chunks/worker_chunk-vite-D2sZgpE4.js")

// TypeError: Failed to resolve module specifier 'http://localhost:4173./worker-chunks/worker_chunk-index-JyeH1t5q.js'

I'm not sure if there's any mechanism possible to actually handle this though. (Maybe main script needs to tell workers where the main script is and compute relative path based on that?)

Also base can be a full url to cdn https://vitejs.dev/config/shared-options.html#base, so that might also break self.location.origin + config.rawBase.

[proc07]

Can this be solved in this way? Use config.build.outDir to extract the path we need, if outDir = "dist" or './dist' use origin + / + url, if outDir = 'dist/es/' use origin + /es/.

Suggested change

	return `import(self.location.origin + "${config.rawBase + importUrl}")`
	let outDir = config.build.outDir
	if (outDir.startsWith('./')) {
	outDir = outDir.slice(2) // Removes the './'
	}
	// Filter out the first folder
	let basePath = outDir
	.split('/')
	.filter((path) => path)
	.slice(1)
	.join('/')
	if (basePath === '') {
	basePath = '/'
	} else {
	basePath = `/${basePath}/`
	}

[hi-ogawa]

I don't think that's how relative base should be handled. Relative base means it's relocatable and shouldn't hard-code /dist in the output.
For example, for this playground, simple http server like sirv should be able to serve the app from an arbitrary root directory.

pnpm -C playground/worker build:relative-base

# app available in http://localhost:8080
pnpm dlx sirv-cli playground/worker/dist/relative-base

# app available in http://localhost:8080/relative-base
pnpm dlx sirv-cli playground/worker/dist

# app available in http://localhost:8080/dist/relative-base
pnpm dlx sirv-cli playground/worker

[proc07]

You're right, we can't get the full base path, maybe set it up from the main script.

[hi-ogawa]

I think this is a tricky problem to solve in a general manner. For example, I think it's technically possible to have an inline worker inside inline worker, but I would imagine supporting that would cause more complication.
We need a discussion with a team, but it might be acceptable, for example, to limit the use case only for non relative base case to simplify things.

Either way, thanks for initiating a PR 👍