Run pants in docker from Apple M1 with --platform linux/amd64 fail with "Function not implemented"

[gabrielhora]

Describe the bug

I'm trying to run pants inside a docker container using linux/amd64 platform from a M1 Mac. The following exception is raised when running pants --version. As far as I understand this is coming from some QEMU emulation layer, but I'm not versed enough in it to know what is happening.

#8 [5/5] RUN pants --no-pantsd --version
#8 20.09 Bootstrapping Pants 2.15.0 using cpython 3.9.16
#8 20.09 Installing pantsbuild.pants==2.15.0 into a virtual environment at /root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0
#8 42.24      ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 2.1/2.1 MB 3.9 MB/s eta 0:00:00
#8 44.80      ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 819.3/819.3 KB 18.9 MB/s eta 0:00:00
#8 45.23      ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 64.5/64.5 KB 7.2 MB/s eta 0:00:00
#8 116.3 New virtual environment successfully created at /root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0.
#8 127.7 Exception caught: (builtins.ValueError)
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/bin/pants", line 8, in <module>
#8 127.7     sys.exit(main())
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/bin/pants_loader.py", line 123, in main
#8 127.7     PantsLoader.main()
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/bin/pants_loader.py", line 110, in main
#8 127.7     cls.run_default_entrypoint()
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/bin/pants_loader.py", line 92, in run_default_entrypoint
#8 127.7     exit_code = runner.run(start_time)
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/bin/pants_runner.py", line 99, in run
#8 127.7     runner = LocalPantsRunner.create(
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/bin/local_pants_runner.py", line 86, in create
#8 127.7     options_initializer = options_initializer or OptionsInitializer(
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/init/options_initializer.py", line 103, in __init__
#8 127.7     self._bootstrap_scheduler = create_bootstrap_scheduler(options_bootstrapper, executor)
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/init/options_initializer.py", line 75, in create_bootstrap_scheduler
#8 127.7     EngineInitializer.setup_graph(
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/init/engine_initializer.py", line 198, in setup_graph
#8 127.7     return EngineInitializer.setup_graph_extended(
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/init/engine_initializer.py", line 338, in setup_graph_extended
#8 127.7     scheduler = Scheduler(
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/engine/internals/scheduler.py", line 216, in __init__
#8 127.7     self._py_scheduler = native_engine.scheduler_create(
#8 127.7 
#8 127.7 Exception message: Failed to begin watching the filesystem: Function not implemented (os error 38)
#8 127.7 NoneType: None
#8 ERROR: process "/bin/sh -c pants --no-pantsd --version" did not complete successfully: exit code: 1
------
 > [5/5] RUN pants --no-pantsd --version:
#8 127.7     EngineInitializer.setup_graph(
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/init/engine_initializer.py", line 198, in setup_graph
#8 127.7     return EngineInitializer.setup_graph_extended(
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/init/engine_initializer.py", line 338, in setup_graph_extended
#8 127.7     scheduler = Scheduler(
#8 127.7   File "/root/.cache/nce/c55ee58a557d20bd4b109870e5a01b264c0d501ce817cce29502b2552903834d/bindings/venvs/2.15.0/lib/python3.9/site-packages/pants/engine/internals/scheduler.py", line 216, in __init__
#8 127.7     self._py_scheduler = native_engine.scheduler_create(
#8 127.7 
#8 127.7 Exception message: Failed to begin watching the filesystem: Function not implemented (os error 38)
#8 127.7 NoneType: None
------
Dockerfile:10
--------------------
   8 |     
   9 |     RUN echo "[GLOBAL]\npants_version = \"2.15.0\"" >> pants.toml
  10 | >>> RUN pants --no-pantsd --version
  11 |     
--------------------
ERROR: failed to solve: process "/bin/sh -c pants --no-pantsd --version" did not complete successfully: exit code: 1

Pants version

2.15 (same with 2.16)

OS

Apple M1 Pro MacOS with Ventura 13.4.1

Additional info

The following simple dockerfile is enough to reproduce this problem (at least in a M1 device).

FROM --platform=linux/amd64 debian:stable-slim

ENV PATH="/root/bin:$PATH"

RUN apt-get update && apt-get install -y curl

RUN curl --proto '=https' --tlsv1.2 -fsSL https://static.pantsbuild.org/setup/get-pants.sh | bash

RUN echo "[GLOBAL]\npants_version = \"2.16.0\"" >> pants.toml
RUN pants --no-pantsd --version

[huonw]

Sorry for the trouble here and thanks for the reproducer. I've tripped over this too.

I think you can work around this by also setting --no-watch-filesystem: pants --no-pantsd --no-watch-filesystem --version. This is documented in https://www.pantsbuild.org/docs/prerequisites#macos, but it'd be far better for pants itself to detect this error specifically and provide a better explanation, so let's keep this open.

BTW, some other notes:

• you may hit Running ./pants -no-pantsd --no-watch-filesystem version under linux/amd64 docker image on ARM macOS requires ~4G of memory #17622 if you're using Pants in this configuration and thus need to provide enough memory to the docker container, FYI
• depending on what you're doing, an alternative to running pants inside docker might be to run pants natively and let it run processes in docker images, via environments: https://www.pantsbuild.org/docs/environments (although there's still some rough edges there)

[gabrielhora]

Thank you @huonw, using --no-watch-filesystem does solve my problem. Sorry I missed that part in the documentation, the installation worked via homebrew and I just assumed I had all the prerequisites and didn't look in that page.

I agree with you though that if this is a know issue it would make it easier to find the solution with a more specific error message. Or maybe, as an alternative, a reference to the error message Function not implemented in the documentation would make it easier to Google (I tried to google site:www.pantsbuild.org Function not implemented and found no solution).