[BUG][PYTHON] Generated models and optional parameters

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• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
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Description

I am using the version 7.0.0 dated 2023/05/16 to generate Python code and the models do not take into account the readonly and optional flags from the spec file. As an example, my API includes a component called DataCollectionPlan, and a POST for the same component schema.

In order to use the example code, I must declare the Python object with all the optional and readonly parameters, such as id or description. The id is not necessary when using POST, while the optionals can be set to None, but this is not the correct way to treat optional object parameters.

openapi-generator version

7.0.0 dated 2023/05/16

OpenAPI declaration file content or url

The YAML section of the component.

    DataCollectionPlan:
      type: object
      properties:
        id:
          type: string
          readOnly: true
        name:
          type: string
        description:
          type: string
        kafkaTopic:
          type: string
          description:
        intervalInMinutes:
          type: number
        equipment:
          type: object
          properties:
            id: 
             type: string
        equipmentConnection:
          type: object
          properties:
            id: 
             type: string
        subscribers:
          type: array
          items:
            $ref: '#/components/schemas/Subscriber'
        requestList:
          type: array
          items:
            oneOf:
              - $ref: '#/components/schemas/AlarmRequest'
              - $ref: '#/components/schemas/EventRequest'
              - $ref: '#/components/schemas/TraceRequest'
        appKey:
          type: string
          readOnly: true
          description: UUID of the App which created this DCP.
      required:
        - id
        - name
        - equipment
        - equipmentConnection
        - requestList

The YAML section of the POST.

    post:
      summary: Create a Data Collection Plan
      description:       
      tags:
        - DataCollectionPlan
      parameters: 
      - in: header
        required: true
        name: X-App-Key
        schema:
          type: string
        description: App Key in UUID format
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/DataCollectionPlan'

Generation Details

I tried both with Java version 8 and using the Docker container from openapitools/openapi-generator-cli:latest.

Steps to reproduce

Just generated code as normal.

Related issues/PRs

None.

Suggest a fix

This was not an issue in the version 7.0.0 dated 2022/05/26. It seems like the model files had a different structure, and they took into account when model is used for POST or for results from PUT.

Start by reproducing generation for the supplied DataCollectionPlan schema and POST declaration, then compare the generated Python model structure with the older 7.0.0 version dated 2022/05/26. Done means readOnly fields such as id and appKey, plus optional properties, are not required when constructing the model for the POST use case.