Cannot read model with pydantic 2.12

[visr]

Ribasim Python users should avoid pydantic 2.12 or higher for now, e.g. uv add pydantic=2.11. Pixi or Conda users don't need to as the cap has been applied in the feedstock with conda-forge/ribasim-feedstock#30.

The RijnenIJssel_2025_9_0 model was created with v2025.4.0. I can read it fine with Ribasim Python on the main branch. When reading it with v2025.5.0 you'd expect it to work as well, but I get:

>>> m = ribasim.Model.read(r"c:\Users\visser_mn\Downloads\RijnenIJssel_2025_9_0\wrij.toml")
Traceback (most recent call last):
  File "<python-input-4>", line 1, in <module>
    m=ribasim.Model.read(r"c:\Users\visser_mn\Downloads\RijnenIJssel_2025_9_0\wrij.toml")
  File "C:\ProgramData\DevDrives\set\nl\RijnenIJssel\modellen\.venv\Lib\site-packages\ribasim\model.py", line 334, in read
    return cls(filepath=filepath)  # type: ignore
  File "C:\ProgramData\DevDrives\set\nl\RijnenIJssel\modellen\.venv\Lib\site-packages\pydantic\main.py", line 250, in __init__
    validated_self = self.__pydantic_validator__.validate_python(data, self_instance=self)
  File "C:\ProgramData\DevDrives\set\nl\RijnenIJssel\modellen\.venv\Lib\site-packages\ribasim\input_base.py", line 623, in set_sort_keys
    field = cls.model_fields[getattr(info, "field_name")]
            ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
KeyError: 'basin'

The error seems to be on the basin section of the TOML:

The TOML is:

starttime = 2017-01-01 00:00:00
endtime = 2018-01-01 00:00:00
crs = "28992"
input_dir = "input"
results_dir = "results"
ribasim_version = "2025.4.0"

[basin]
time = "basin_time.arrow"

We could of course do a new release, but I want to understand what this is. And also if it is just this model, or other models as well.

[visr]

This is odd, on #2630 I see similar test failures, on Python 3.12, but not on 3.13. See for instance https://github.com/Deltares/Ribasim/actions/runs/18386359165/job/52385698174?pr=2630:

cls = <class 'ribasim.config.Basin'>, v = Node
None
info = ValidationInfo(config={'title': 'Basin', 'extra_fields_behavior': 'forbid', 'validate_default': True, 'validate_by_alias': True, 'validate_by_name': True}, context=None, data={}, field_name=None)

    @field_validator("*")
    @classmethod
    def set_sort_keys(cls, v: object, info: ValidationInfo) -> object:
        """Set sort keys for all TableModels if present in FieldInfo."""
        if isinstance(v, TableModel):
>           field = cls.model_fields[getattr(info, "field_name")]
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
E           KeyError: None

python/ribasim/ribasim/input_base.py:627: KeyError

I now tried handling this with isinstance(v, TableModel) and info.field_name is not None, as the Pydantic docs state it can be None, though I don't understand when.

[visr]

Oh now I see the connection of both previous posts: pydantic 2.12 just came out with some minor breaking changes that seem to hit us. On #2630 I ran pixi update and only on Python 2.12 it could pull this new version in. Let's see what 7ee485c does.

https://pydantic.dev/articles/pydantic-v2-12-release#changes

@Fati-Mon could you try pixi add pydantic=2.11? That should avoid this issue for now.

[Fati-Mon]

Hi @visr , yes this seems to be working for now. Thanks.