Multiple use of allOf not working in python

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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)?
• What's the version of OpenAPI Generator used?
• Have you search for related issues/PRs?
• What's the actual output vs expected output?
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Description

The use of allOf more than once, is not working in python. Specifically, models that use an allOf import on a model that also uses allOf are not correctly constructed.

using

address:      # Can be referenced via '#/components/schemas/address'
  type: object
  properties:
    al:
      type: array
      items:
        $ref: 'https://host014.etsit.upm.es/schemas/test/maitred/msg/net_point.yaml#/network_point'
    did:
      type: string
    sid:
      type: integer
      format: int32

to build

header:
  type: object
  allOf:
    - $ref: 'https://host014.etsit.upm.es/schemas/test/maitred/base/address.yaml#/address'
  properties:
    tag:
      type: string
    f:
      type: integer
      format: int32
      enum:
        - -1
        - 0
        - 1
        - 2
        - 3
        - 4
      default: 0
    ts:
      type: integer
      format: int64

The corresponding generator header class results in

class Header(Model):

    def __init__(self, tag=None, f=0, ts=None, al=None, did=None, sid=None):  # noqa: E501

Everything is fine, including the enumerator.

Now, if it is then used to build

message:
  type: object
  allOf:
    - $ref: 'https://host014.etsit.upm.es/schemas/test/maitred/base/message_header.yaml#/header'
  properties:
    pl:
      type: object

The resulting class results is

class Message(Model):

    def __init__(self, al=None, did=None, sid=None, pl=None):  # noqa: E501

Only the address field are included and components native to header have disappeared.

Its not just a simple template mistake in not including the inheritance of the base class. There is a problem in including the properties in the base model in the derived class. Something is going wrong with the generation of the vars and their variations.

Also, if inheritance was the target design, then there is an ambiguity with the imports. The message model has

from maitred.base.models.header import Header
from maitred.base.models.network_point import NetworkPoint

Where the NetworkPoint should not be necessary at this class level.

A rethink in terms of the constructor arguments will also be needed.

Note, the schema generates a model that, so far works fine in Java.

openapi-generator version

4.3.1-SNAPSHOT and 4.3.0

OpenAPI declaration file content or url

The corresponding full model files are published as:

network_point
address
header
message

Command line used for generation

N/A

Steps to reproduce

N/A

Related issues/PRs

N/A

Suggest a fix

The simplest hack would be to modify the template to inherite the parent class and live with the fact that the base properties on the deepest model will be overloaded, but clarifying the var list would be nice.

Start with the published network_point, address, message_header, and gen_message schema files, then compare the generated Header and Message classes. Trace how nested allOf properties, constructor variables, and imports are represented, and verify that the generated Message includes the expected header fields without unnecessary imports.