Handle the infamous raw deflate response from old servers

[jimmywarting]

Bug Description

Something node-fetch and browser could handle was the infamous raw deflate response from old servers
basically if the coding is either: coding === 'deflate' || coding === 'x-deflate'
then read the first byte. if it match chunk[0] & 0x0F) === 0x08 then use zlib.createInflate() otherwise use zlib.createInflateRaw()

Reproducible By

You already have a test for it here:

undici/test/node-fetch/main.js

Lines 663 to 672 in 51fa0fe

	xit('should decompress deflate raw response from old apache server', () => {
	const url = `${base}deflate-raw`
	return fetch(url).then(res => {
	expect(res.headers.get('content-type')).to.equal('text/plain')
	return res.text().then(result => {
	expect(result).to.be.a('string')
	expect(result).to.equal('hello world')
	})
	})
	})

Expected Behavior

Additional context

Relevant part that needs fixing:

undici/lib/fetch/index.js

Lines 2018 to 2019 in 51fa0fe

	} else if (coding === 'deflate') {
	decoders.push(zlib.createInflate())

how node-fetch solved it:
https://github.com/node-fetch/node-fetch/blob/7b86e946b02dfdd28f4f8fca3d73a022cbb5ca1e/src/index.js#L314-L350

[mcollina]

Thanks for reporting! Would you like to send a Pull Request to address this issue? Remember to add unit tests.

[jimmywarting]

don't exactly know how to translate it into your codebase. using pass through / transform stream or anything.

Remember to add unit tests.

just need to enable a existing test in the codebase that's currently skipped