Fetch with integrity option fails on "TypeError: response.arrayBuffer is not a function"

[jelmervdl]

Version

18.4.0

Platform

Darwin MPB16.local 21.6.0 Darwin Kernel Version 21.6.0: Sat Jun 18 17:07:25 PDT 2022; root:xnu-8020.140.41~1/RELEASE_X86_64 x86_64

Subsystem

fetch

What steps will reproduce the bug?

Using fetch() with the integrity option seems to consistently fail, throwing from an internal library function.

Simplest example I could come up with:

async function test() {
	const response = await fetch('https://storage.googleapis.com/bergamot-models-sandbox/0.3.3/enes/qualityModel.enes.bin', {
		integrity: 'sha256-zhQfjp5Qpe9NjjJDonSxc03FMvaWN5Sohp3ONay1Q8I='
	})

	console.log(response);
}

test();

How often does it reproduce? Is there a required condition?

Seems to be consistent. Without the integrity option for the request, it succeeds. But with it, it throws. I have not tried it with different hosts.

What is the expected behavior?

The above script retuning and printing the Response object instead of throwing.

What do you see instead?

(node:22831) ExperimentalWarning: The Fetch API is an experimental feature. This feature could change at any time
(Use `node --trace-warnings ...` to show where the warning was created)
node:internal/deps/undici/undici:5555
          p.reject(Object.assign(new TypeError("fetch failed"), { cause: response.error }));
                                 ^

TypeError: fetch failed
    at Object.processResponse (node:internal/deps/undici/undici:5555:34)
    at node:internal/deps/undici/undici:5877:42
    at node:internal/process/task_queues:140:7
    at AsyncResource.runInAsyncScope (node:async_hooks:203:9)
    at AsyncResource.runMicrotask (node:internal/process/task_queues:137:8)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5) {
  cause: TypeError: response.arrayBuffer is not a function
      at mainFetch (node:internal/deps/undici/undici:5773:38)
      at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
}

Additional information

No response

[mcollina]

Thanks for reoporting! I don't think integrity is implemented or tested at all:

undici/lib/fetch/util.js

Lines 342 to 344 in 2944587

	function matchRequestIntegrity (request, bytes) {
	return false
	}

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

[KhafraDev]

The integrity option isn't supported, but the actual error stems from response not being an instance of the WHATWG Response class, but an internal, but separate, response object.

To fix the error, the fully read a body algorithm needs to be implemented.

---

Hopefully if integrity is implemented, it will encourage other platforms to add it as well. A Deno maintainer has previously stated that they didn't wish to implement any of the fields listed in wintercg/fetch#6 (see: comment), which happened to include integrity.