[Python] Fix python template for list and dicts of dicts

[ottmar-zittlau]

I had some issues generating python code for dicts.
I made some changes to the corresponding template to fix these.

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Summary by cubic

Fixes Python generator templates to correctly handle lists of dicts and dicts of dicts, ensuring nested models in arrays/maps serialize to valid JSON and deserialize reliably. Adds spec fixtures, tests, and generated samples to cover arrays of maps and maps of maps.

• Bug Fixes
  • Lists of dicts (arrays of maps): serialize inner model values with to_dict; deserialize each value with Model.from_dict.
  • Dicts of dicts (maps of maps): serialize nested dict values with to_dict and rebuild them during from_dict.
  • Container branching: add explicit array-of-map and map-of-map paths; use obj["field"] when iterating to avoid None.items() errors.

^{Written for commit 7c1a8fd. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 1 file

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="modules/openapi-generator/src/main/resources/python/model_generic.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/python/model_generic.mustache:375">
P1: `from_dict` crashes when map-of-map field is present but set to null. The condition `"{{{baseName}}}" in obj` only checks key presence, not value. If the input contains the key with explicit null value (valid for nullable properties), `obj["{{{baseName}}}"].items()` will raise `AttributeError: 'NoneType' object has no attribute 'items'`.</violation>
</file>

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[wing328]

thanks for the fix

can you please add a test schema to modules/openapi-generator/src/test/resources/3_0/python/petstore-with-fake-endpoints-models-for-testing.yaml and follow step 3 to regenerate the samples ?

(please run the sample update command twice)

[wing328]

Thanks for the PR but your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account

[ottmar-zittlau]

Thanks for the PR but your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account

Thanks - I think I managed to fix it.

[ottmar-zittlau]

thanks for the fix

can you please add a test schema to modules/openapi-generator/src/test/resources/3_0/python/petstore-with-fake-endpoints-models-for-testing.yaml and follow step 3 to regenerate the samples ?

(please run the sample update command twice)

@wing328 Thanks for the quick feedback. I added two test schemas - one is a dict of dicts with non-primitive types and the other one is a list of dicts. I also generated and added the samples.

I think that the code generated by pydantic v1 is wrong (cf. https://github.com/OpenAPITools/openapi-generator/pull/23112/changes#diff-fda969d5c6bc4a395c4b0f943f87e8fd63bbe315e680336db016f1ffcec967b0R65) - to_dict is called on the values of a dict of dicts, i.e. on dicts that don't have this property. Should I fix this? And if yes, in this PR or separately?

[wing328]

And if yes, in this PR or separately?

with a separate PR please

[wing328]

cc @cbornet (2017/09) @tomplus (2018/10) @krjakbrjak (2023/02) @fa0311 (2023/10) @multani (2023/10)