No compiler on system, so can't pip install prefect - any workaround suggestions?

[sgbaird]

AccelerationConsortium/ac-dev-lab#109 (comment)

[sgbaird]

copied from AccelerationConsortium/ac-dev-lab#109 (comment):

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It turns out that Prefect requires Pendulum 3.0.0:

Collecting pendulum<4,>=3.0.0 (from prefect==3.3.4)

However, Pendulum 3.0.0 has a known bug when building on 32-bit systems, as noted here. Unfortunately, the OT-2 runs on a Pi 3 with 32-bit armv7l, which explains why I always got stuck.

It looks like the issue was closed via this commit, but it hasn't yet been included in the latest release (the commit is from last November, and the latest release is from 2023).

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cc @masonmenges, who mentioned that the pendulum dependency may be removed at some point.

Seems there's quite a lot of existing content related to pendulum within Prefect:

• consolidate use of pendulum so that it can be replaced #16910
• Add Python 3.13 support #17577

cc @Neil-YL

[cicdw]

@sgbaird could you use Python 3.13? Pendulum shouldn't be installed when using Python 3.13

Ref:

prefect/pyproject.toml

Line 65 in e8852a9

"pendulum>=3.0.0,<4; python_version<'3.13'",

[Neil-YL]

Happen to find this, not sure if this limits to the simulator or also on the robot.
https://support.opentrons.com/s/article/Simulating-OT-2-protocols-on-your-computer

Opentrons software requires Python 3.10 and the pip package installer. Newer versions of Python aren’t yet supported.

If you need to install Python, we recommend using the official distribution, but Opentrons software will work with other installation methods like Anaconda.

[sgbaird]

True, and agreed not sure if that applies only to the simulator (that package seems to be quite specific to the simulator). A first interim check would probably be to try installing all dependencies except pendulum to see if there are other conflicts, too.

[Neil-YL]

My plan is to use my previous cross-compiling Docker setup, prepare a Python 3.13 virtual environment, install Prefect, and if there are no other issues, move it to the OT-2.

Still have doubts about whether we can actually run the Opentrons Python protocol to control the robot through Prefect with Python 3.13.

[cicdw]

The good news is that we will remove pendulum as a dependency across all Python versions. We're currently doing a slow rollout starting with Python 3.13 because datetime handling is such a core piece of Prefect's functionality, and 3.13 seems to be going well, but we don't have a firm date yet as to when we'll complete the rollout.

[sgbaird]

A first interim check would probably be to try installing all dependencies except pendulum to see if there are other conflicts, too.

Unfortunately, even removing pendulum and installing the rest of pyproject.toml (albeit on Python 3.10), we end up with:

# pip install -e .
Obtaining file:///data/prefect-main
  Installing build dependencies ... done
  Checking if build backend supports build_editable ... done

[notice] A new release of pip is available: 24.2 -> 25.1.1
[notice] To update, run: python -m pip install --upgrade pip
ERROR: Exception:
Traceback (most recent call last):
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/cli/base_command.py", line 106, in _run_wrapper
    status = _inner_run()
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/cli/base_command.py", line 97, in _inner_run
    return self.run(options, args)
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/cli/req_command.py", line 67, in wrapper
    return func(self, options, args)
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/commands/install.py", line 386, in run
    requirement_set = resolver.resolve(
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/resolution/resolvelib/resolver.py", line 76, in resolve
    collected = self.factory.collect_root_requirements(root_reqs)
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/resolution/resolvelib/factory.py", line 545, in collect_root_requirements
    reqs = list(
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/resolution/resolvelib/factory.py", line 501, in _make_requirements_from_install_req
    cand = self._make_base_candidate_from_link(
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/resolution/resolvelib/factory.py", line 212, in _make_base_candidate_from_link
    self._editable_candidate_cache[link] = EditableCandidate(
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/resolution/resolvelib/candidates.py", line 329, in __init__
    super().__init__(
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/resolution/resolvelib/candidates.py", line 159, in __init__
    self.dist = self._prepare()
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/resolution/resolvelib/candidates.py", line 236, in _prepare
    dist = self._prepare_distribution()
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/resolution/resolvelib/candidates.py", line 339, in _prepare_distribution
    return self._factory.preparer.prepare_editable_requirement(self._ireq)
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/operations/prepare.py", line 698, in prepare_editable_requirement
    dist = _get_prepared_distribution(
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/operations/prepare.py", line 72, in _get_prepared_distribution
    abstract_dist.prepare_distribution_metadata(
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/distributions/sdist.py", line 54, in prepare_distribution_metadata
    self.req.isolated_editable_sanity_check()
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/req/req_install.py", line 541, in isolated_editable_sanity_check
    and not self.supports_pyproject_editable
  File "/usr/lib/python3.10/functools.py", line 981, in __get__
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_internal/req/req_install.py", line 258, in supports_pyproject_editable
    return "build_editable" in self.pep517_backend._supported_features()
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_vendor/pyproject_hooks/_impl.py", line 180, in _supported_features
    return self._call_hook("_supported_features", {})
  File "/var/user-packages/usr/lib/python3.10/site-packages/pip/_vendor/pyproject_hooks/_impl.py", line 402, in _call_hook
    raise BackendUnavailable(
pip._vendor.pyproject_hooks._impl.BackendUnavailable: Cannot import 'hatchling.build'

copied from AccelerationConsortium/ac-dev-lab#109 (comment)