How to configure openapi-generator-cli to include None values for nullable fields in Pydantic models

Question

I'm using openapi-generator-cli to generate Python clients, and it's working great except for a specific scenario. I need to send requests to an external service where all nullable fields must be included even if their values are None. When I generate the client with openapi-generator-cli, it creates models with a to_dict method like this:

def to_dict(self) -> Dict[str, Any]:
    """Return the dictionary representation of the model using alias.

    This has the following differences from calling pydantic's
    `self.model_dump(by_alias=True)`:

    * `None` is only added to the output dict for nullable fields that
      were set at model initialization. Other fields with value `None`
      are ignored.
    """
    excluded_fields: Set[str] = set([
    ])

    _dict = self.model_dump(
        by_alias=True,
        exclude=excluded_fields,
        exclude_none=True,
    )

Is there a way to configure openapi-generator-cli to allow including None values for nullable fields in the to_dict method? This will be accomplished if exclude_none=False but I don't find any directive for openapi-generator for this.

Let's say I have a Python dictionary like this:

request_data = {
    "account": None,
    "lastName": "Doe",
    "firstName": "Jon",
    "middleInitial": None,
    "companyName": None,
    "isOrganization": False,
    "address": {
        "type": "P",
        "address1": "5171 California Avenue",
        "address2": "Suite 200",
        "address3": None,
        "address4": None,
        "locality": "Irvine",
        "region": "CA",
        "postalCode": "92617",
        "countryCode": "US"
    }
}

In this example, even though some fields like "account", "middleInitial", and "companyName" are None, I need them to be included in the request sent to the external service.

Additional Note:

Perhaps the issue lies not in the configuration of openapi-generator but in the Swagger file used to create these models. However, I couldn't find any configuration in the Swagger file that results in the desired models. Here's a snippet of my Swagger models:

User:
  type: object
  required:
    - address
  properties:
    account:
      type: string
      default: null 
    middleInitial:
      type: string
      default: null 
    lastName: 
      type: string
      default: null 
    firstName: 
      type: string
      default: null 
    companyName:
      type: string
      default: null 
    isOrganization: 
      type: boolean
      default: null 
    address: 
      $ref: "#/components/schemas/Adress"

Answer 1

I found a solution on this one. I used a mustache template overriding the same template on the docker cli.

docker run --rm \
    -v ${PWD}:/local openapitools/openapi-generator-cli:latest-release generate \
    --input-spec https://api.swaggerhub.com/apis/supercoolapi/$API_VERSION?resolved=true \
    --auth "Authorization: ${SWAGGER_API_TOKEN}" \
    --generator-name python \
    --output /local \
    --additional-properties=packageVersion=$PACKAGE_VERSION,packageName=$PACKAGE_NAME,library=asyncio \
    --template-dir /local/templates

I used this template and overwritted how to_dict method is created.