Defer Loader fails to load raw headers from dev server. Works in production.

[youngkidwarrior]

What version of Remix are you using?

1.12.0

Are all your remix dependencies & dev-dependencies using the same version?

• Yes

Steps to Reproduce

You could clone BrightID Discord Bot

Expected Behavior

Loader returns deferred data properly

Here is a link to the loader (written in Rescript) https://github.com/ShenaniganDApp/brightid-discord-bot/blob/212d4dbdf1fa71682fb7064f923ada2a3a510edc/apps/web/app/res-routes/guilds/GuildId_Index.res#L27

Actual Behavior

remix_failed_raw.mov

I have a loader that is supposed to return deferred data. On page load, the loader is returning undefined for every field.

This is the error:

TypeError: Cannot read properties of undefined (reading 'raw')
    at sendRemixResponse (/Users/username/Documents/BrightIDbot/node_modules/@remix-run/express/dist/server.js:85:65)
    at /Users/username/Documents/BrightIDbot/node_modules/@remix-run/express/dist/server.js:40:13
    at processTicksAndRejections (node:internal/process/task_queues:95:5)

and this is the function the error points to in @remix-run/express

async function sendRemixResponse(res, nodeResponse) {
  res.statusMessage = nodeResponse.statusText;
  res.status(nodeResponse.status);
  for (let [key, values] of Object.entries(nodeResponse.headers.raw())) {  // --> Line 85
    for (let value of values) {
      res.append(key, value);
    }
  }
  if (nodeResponse.body) {
    await node.writeReadableStreamToWritable(nodeResponse.body, res);
  } else {
    res.end();
  }
}

The odd thing is, the exact same code works in production at https://bot.brightid.org, which makes me think it is a dev server issue. I recently updated to v1.12.0, so I tried reverting those changes, however, the issue persisted.

[MaximeGratens]

Same issue with my project !

[youngkidwarrior]

It seems like this issue is arising from defer(). Not sure how to fix it.

[bluefire2121]

This is fixed in 1.14.0 I believe #5345

[robase]

Still hitting this issue using 1.14.3

Edit: Seems to be fixed in 1.15.0

[brophdawg11]

I'm going to close this out since I believe it should have been fixed by #5345 in 1.14.0. Please re-open with a minimal reproduction if this is not the case!