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Multiple body-types in an endpoint with same model (referenced via `$ref`) results in ambiguity in generated code

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#1,004 1 comment 5 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
openapi, python
Domain
api, tooling

Research direction

Start by tracing how the generator handles the OpenAPI requestBody content entries and produces the generated _get_kwargs function. Reproduce the issue with the provided JSON snippet, then add coverage for both application/json and multipart/form-data; done means the generated client selects the correct body handling without ambiguous identical conditions.

Written by the indexing model from the issue text.

Description

Python Version OpenAPI Client Generator Version
3.11.6 0.18.0

Actual Behavior

When an endpoint has multiple body types, each referencing the same model (via a $ref key), the generator generates the same class name for each body types, which results then in the following generated code:

def _get_kwargs(
    # ...
):
    # ...

    if isinstance(body, WritableJournalEntryRequest):
        _json_body = body.to_dict()
 
        _kwargs["json"] = _json_body
        headers["Content-Type"] = "application/json"
    if isinstance(body, WritableJournalEntryRequest):
        _files_body = body.to_multipart()
 
        _kwargs["files"] = _files_body
        headers["Content-Type"] = "multipart/form-data"
 
    # ...

As you can see, both if-statement's conditions will resolve to True, therefore only the last body type will be used.

Desired Behavior

The body-type should be part of the generated class name to avoid such ambiguities.
Or an if/elseif/else should be used in the template (which would result in the first one being applied ONLY).

OpenAPI Spec File

The OpenAPI spec is from Netbox, but here is the relevant snippet:

"requestBody": {
    "content": {
        "application/json": {
            "schema": {
                "$ref": "#/components/schemas/WritableJournalEntryRequest"
            }
        },
        "multipart/form-data": {
            "schema": {
                "$ref": "#/components/schemas/WritableJournalEntryRequest"
            }
        }
    },
    "required": true
},
Dominant language
Python
Stars
2k
Forks
293
Avg merge
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Merged PRs (30d)
1

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