CompressionStream hangs

[davewasmer]

Version

v21.6.1

Platform

Darwin ****** 23.0.0 Darwin Kernel Version 23.0.0: Fri Sep 15 14:42:42 PDT 2023; root:xnu-10002.1.13~1/RELEASE_X86_64 x86_64

Subsystem

globals, streams/web

What steps will reproduce the bug?

function from(src) {
  return new ReadableStream({
    start(controller) {
      controller.enqueue(src);
      controller.close();
    },
  });
}

async function read(stream) {
  const reader = stream.getReader();
  const chunks = [];
  while (true) {
    const { done, value } = await reader.read();
    if (done) break;
    chunks.push(value);
  }
  return chunks;
}

await read(from(new ArrayBuffer([0, 0, 0, 0])).pipeThrough(new CompressionStream('gzip')));

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

Every time

What is the expected behavior? Why is that the expected behavior?

Should resolve to [Uint8Array(10), Uint8Array(10)].

What do you see instead?

Nothing - reader.read() hangs and never resolves.

Additional information

Running the code snippet in Chrome devtools console produces the correct outcome. Using 'deflate' rather than 'gzip' has no effect, it still hangs.

[IlyasShabi]

I explored the issue and it appears that Nodejs expects the "chunk" argument in the _write function to be either a string, Buffer, or Uint8Array, not an ArrayBuffer.

A potential workaround involves converting the ArrayBuffer to a Buffer before processing it:

const buffer = Buffer.from(new ArrayBuffer([0, 0, 0, 0]));

@nodejs/streams I experimented with converting ArrayBuffer to Buffer directly within the _write function like this:

if (Stream._isAnyArrayBuffer(chunk)) {
    encoding = 'buffer';
    chunk = Buffer.from(chunk, encoding);
}

It worked, but I'm not convinced it's the best way to add support ArrayBuffer

[marco-ippolito]

Hi @IlyasShabi would you like to open a PR with your solution? I think it's worth giving it a try