openapi-generator: [BUG][Python] Attribute-style access fails for model properties

Bug Report Checklist

Have you provided a full/minimal spec to reproduce the issue?
Have you validated the input using an OpenAPI validator (example)?
Have you tested with the latest master to confirm the issue still exists?
Have you searched for related issues/PRs?
What’s the actual output vs expected output?
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Description

See the spec below for the model definitions. I was under the impression the following code is legal, but it raises an error:

from openapi_client.models import Foo
f = Foo(bar='bar')
f.bar # this raises an AttributeError
f['bar'] # this works fine

openapi-generator version

v6.2.1, also tested on master

OpenAPI declaration file content or url

openapi: 3.0.3
info:
  title: APMS
  version: '0.1'
paths:
  /foo:
    post:
      tags:
        - test
      summary: Test
      operationId: create_foo
      responses:
        '200':
          description: ok
components:
  schemas:
    Foo:
      type: object
      properties:
        bar:
          type: string
          example: foobar

Generation Details

docker run -v $PWD/spec.yaml:/spec.yaml -v $PWD/client:/client -it openapitools/openapi-generator-cli:latest generate -i /spec.yaml -g python -o /client

Steps to reproduce

Generate the spec above

Related issues/PRs

Tried, but couldn’t find anything.

Suggest a fix

After looking at the generated code for a while, I found a solution. In https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/resources/python/schemas.handlebars#L1721 , changing

if name not in self.__class__.__annotations__:

if name not in self.MetaOapg.properties.__annotations__:

seems to resolve the problem. However, since there’s a lot of __new__ magic in the generated code, I’m not sure if this is a real fix.

About this issue

Original URL
State: closed
Created 2 years ago
Comments: 16 (7 by maintainers)

Most upvoted comments

@ashuk203 this is by design. It already does what you are asking for. Your instance is an instance of type DynamicSchema which is a class that is built on the fly of all validated schemas including the response body schema. Is it is an instance of that spec defined response body class. You can see examples of this here: https://github.com/OpenAPITools/openapi-generator/blob/master/samples/openapi3/client/petstore/python/tests_manual/test_fake_api.py#L59

This is described in the migration guide All validated data is instantiated in an instance that subclasses all validated Schema classes and Decimal/str/tuple/frozendict/NoneClass/BoolClass/bytes/io.FileIO

spacether on Jan 19, 2023

2.0.2 was released with the fix

spacether on May 17, 2023

Dot referenced properties only exist when:

the property is required
the property’s key is a valid python variable name

When those two conditions are met, a dot referenced property is defined. Otherwise one must access the value by the key name. Per item 7 in the readme: https://github.com/OpenAPITools/openapi-generator/tree/v6.6.0/samples/openapi3/client/petstore/python#changes

Note: All optional keys may not exist, so properties are not defined for them

spacether on May 16, 2023

Oh I see, I didn’t look at that part of the docs, so thanks for linking it. I think you can consider this issue resolved now.

Stealthmate on Nov 3, 2022