Feature/bump to python3.12

[mfroelund]

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[mfroelund]

Shall be updated before merge

[uandrae]

Tried on atos and installed naively with poetry after loading python3/3.12.11-01 and got the error below. Is there some uv documentation missing or is it still expected to work with poetry?

[snh@ac6-101 tactus_pr74]$ poetry run tactus case ?tactus/data/config_files/configurations/cy50t2_arome --case-name python3_12 --start-suite 
2026-06-04 09:14:24 | INFO     | Start tactus v1.0.0 --> "tactus case ?tactus/data/config_files/configurations/cy50t2_arome --case-name python3_12 --start-suite"
...
2026-06-04 09:14:30 | INFO     | suite definition: TactusSuiteDefinition
Traceback (most recent call last):
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/.venv/bin/tactus", line 6, in <module>
    sys.exit(main())
             ^^^^^^
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/tactus/logs.py", line 109, in wrapper
    function_rtn = function(*args, **kwargs)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/tactus/__main__.py", line 43, in main
    args.run_command(args=args, config=config)
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/tactus/commands_functions.py", line 151, in create_exp
    start_suite(args, config)
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/tactus/commands_functions.py", line 204, in start_suite
    server = EcflowServer(config, start_command=args.start_command)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/tactus/scheduler.py", line 106, in __init__
    raise ModuleNotFoundError("Ecflow not found")

[mfroelund]

Tried on atos and installed naively with poetry after loading python3/3.12.11-01 and got the error below. Is there some uv documentation missing or is it still expected to work with poetry?

[snh@ac6-101 tactus_pr74]$ poetry run tactus case ?tactus/data/config_files/configurations/cy50t2_arome --case-name python3_12 --start-suite 
2026-06-04 09:14:24 | INFO     | Start tactus v1.0.0 --> "tactus case ?tactus/data/config_files/configurations/cy50t2_arome --case-name python3_12 --start-suite"
...
2026-06-04 09:14:30 | INFO     | suite definition: TactusSuiteDefinition
Traceback (most recent call last):
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/.venv/bin/tactus", line 6, in <module>
    sys.exit(main())
             ^^^^^^
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/tactus/logs.py", line 109, in wrapper
    function_rtn = function(*args, **kwargs)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/tactus/__main__.py", line 43, in main
    args.run_command(args=args, config=config)
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/tactus/commands_functions.py", line 151, in create_exp
    start_suite(args, config)
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/tactus/commands_functions.py", line 204, in start_suite
    server = EcflowServer(config, start_command=args.start_command)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/etc/ecmwf/nfs/dh2_perm_b/snh/git/tactus_pr74/tactus/scheduler.py", line 106, in __init__
    raise ModuleNotFoundError("Ecflow not found")

Yes this PR doesn't outfaces poetry, so it should still work. For me it works, I have

Currently Loaded Modules:
  1) gcc/8.5.0   2) prgenv/gnu   3) ecflow/5.15.1   4) ecmwf-toolbox/2025.10.1.0   5) python3/3.12.11-01

and ran

poetry install;
poetry run tactus case ?tactus/data/config_files/configurations/cy50t2_arome --case-name python3_12 --start-suite;

With uv, my experience is, that you have to tell it to use system packages in order for it to find ecflow:

uv venv --system-site-packages --no-managed-python
uv sync
uv run tactus case ?tactus/data/config_files/configurations/cy50t2_arome --case-name python3_12 --start-suite

[uandrae]

Thanks, but this suggest and update of the documentation, right?

[mfroelund]

Thanks, but this suggest and update of the documentation, right?

Yes, we can do that, but soon pixi will come, but you'll still be able to install with at least uv. So just a question if we should documentation installation procedures for both pixi, uv, (and poetry, if it still works after pixi - I haven't tested) ?

[uandrae]

I think we said in yesterdays meeting that we go for this first and do pixi later to allow e.g. DW on LUMI time to adapt. Do you agree @jacobsnoeijer?

[mfroelund]

I think we said in yesterdays meeting that we go for this first and do pixi later to allow e.g. DW on LUMI time to adapt. Do you agree @jacobsnoeijer?

Yes, I agree. It was just to know, if we then add documentation for uv now, and then either replace it with pixi at some point, or if we'll continue to have documentation for multiple package managers. I don't think I'm against either of the options.

[jacobsnoeijer]

I will try to test this today on LUMI (and if it works also with #75). Hope to give a status update later today

[jacobsnoeijer]

I have a procedure of this PR (together with #75) to be able to launch a suite on LUMI and LEONARDO. On the compute nodes of LUMI we cannot get the gdal anymore. Need to see how we can setup the venv also on the compute nodes there

[jacobsnoeijer]

I have a procedure of this PR (together with #75) to be able to launch a suite on LUMI and LEONARDO. On the compute nodes of LUMI we cannot get the gdal anymore. Need to see how we can setup the venv also on the compute nodes there

In #75: I mentioned the solution to remove explicit loading the gdal module; then the pixi installed gdal can be found.