[python] change Private attr to Class vars

[fa0311]

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[fa0311]

fix: #16685 (comment)

No test exists for this fix.
To add a test, you must set disallowAdditionalPropertiesIfNotPresent to true.

openapi-generator/bin/configs/python.yaml

Line 8 in e2f249b

disallowAdditionalPropertiesIfNotPresent: false

[multani]

@fa0311 in #16655, you completely removed __properties, would it make sense to do the same instead?

I'm asking because using .defaults is a bit of a hack and it doesn't play well with type checking and I was looking for a way to remove it.

I wanted to replace it by cls.model_json_schema()["properties"].keys(), which would return the same, but if we can actually remove all of this, it would even be better.

[wing328]

@fa0311 thanks for the PR. I've filed #16690 to add tests covering disallowAdditionalPropertiesIfNotPresent set to true and could repeat the issue.

[fa0311]

@multani I have come up with a good idea to fix this.
Replace cls.__properties.default with cls.model_fields.keys() and remove __properties.

(However, __discriminator_property_name.default and __discriminator_value_class_map.default remain unresolved.)

[multani]

Replace cls.__properties.default with cls.model_fields.keys() and remove __properties.

This won't work out of the box: cls.model_field contains the names of the fields as they appear in the class definition, but not their "aliased" names.

This will break several tests, you can check.

On the other hand, cls.model_json_schema()["properties"].keys() contains actually the aliased names.

[multani]

@fa0311 Maybe this could actually help: https://docs.pydantic.dev/latest/concepts/models/#automatically-excluded-attributes

[fa0311]

@multani

@fa0311 Maybe this could actually help: https://docs.pydantic.dev/latest/concepts/models/#automatically-excluded-attributes

I was just looking at that myself.
It looks very good

[fa0311]

A type hint is added to __properties and List becomes a reserved word.

[multani]

Yes, this is the good fix 🙇

[wing328]

FYI. Samples updated via 738af45

[wing328]

Tests added via #16690