[Bug]: SystemError: A system error occurred: uv_os_get_passwd returned ENOENT

[ptink]

Version

1.56.1

Steps to reproduce

I have simple docker compose service that I use to run playwright tests

services: 
  playwright:
    image: playwright:v1.56.1
    user: ${USER_ID}:${GROUP_ID}
    userns_mode: host
    working_dir: /app
    volumes:
      - .:/app

docker compose run --rm playwright /app/scripts/run_playwright_tests.sh

where script runs yarn install and playwright test

this service is designed to run both locally and via a ci pipeline on buildkite, so I pass in the USER_ID and GROUP_ID of my user to stop the playwright container from outputting files as root user onto my filesystem, this works locally just fine but when the same service runs on the buildkite agent (AWS Linux 2023 based), the dependencies finish installing but playwright test errors with:-

[WebServer]     SystemError: A system error occurred: uv_os_get_passwd returned ENOENT (no
[WebServer]      such file or directory)
[WebServer]     Code: ERR_SYSTEM_ERROR
 
Error: Process from config.webServer was not able to start. Exit code: 1

I unfortunately cannot reproduce this locally. The build agent uid/gid probably don't exist in /etc/passwd but I'm not following how it manages to run yarn install and playwright test without hitting permission errors in that case (if i try and run it locally as a user not in /etc/passwd then yarn install fails immediately:

groups: cannot find name for group ID 1234
I have no name!@fad3990404dc:/app$ yarn install
➤ YN0065: Yarn will periodically gather anonymous telemetry: https://yarnpkg.com/advanced/telemetry
➤ YN0065: Run yarn config set --home enableTelemetry 0 to disable

Internal Error: EACCES: permission denied, mkdir '/.yarn'
Error: EACCES: permission denied, mkdir '/.yarn'
I have no name!@fad3990404dc:/app$ 

I have seen other bugs that are marked as fixed where people complained about the same issue with jenkins docker agents: #22721 but this seems to be fixed.

Additionally in my case it seems like the issue is caused by not allowing the container to run as root, because if I do run it as root on the buildkite agent it works as expected (but then is awkward to use locally as the output files are owned by root).

The impression I got from this question: #28427 and the paragraph here was that it is fine to run the playwright container as a non-root user- is this not the case?

Expected behavior

playwright tests run as a non-root user inside the docker compose service

Actual behavior

works locally, but when same config is run on a buildkite agent it errors

Additional context

No response

Environment

System:
    OS: Linux 6.6 Ubuntu 24.04.3 LTS 24.04.3 LTS (Noble Numbat)
    CPU: (22) x64 Intel(R) Core(TM) Ultra 7 155H
    Memory: 13.65 GB / 15.35 GB
    Container: Yes
  Binaries:
    Node: 22.20.0 - /usr/bin/node
    Yarn: 1.22.22 - /usr/bin/yarn
    npm: 10.9.3 - /usr/bin/npm
  Languages:
    Bash: 5.2.21 - /usr/bin/bash

[Skn0tt]

The error log you're seeing stems from the webserver you have configured in your playwright.config.ts, not from Playwright itself. Try running the webserver directly to see if it also occurs, if it does then it's not a bug with Playwright. If it doesn't, then please provide us with a reproduction case, otherwise we can't investigate.