[BUG] [Python] Incorrect name attribute when uploading file / form data

Created by: plague006

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?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

Uploads to API endpoints were not working. The server says that no file was uploaded. I traced the cause to

openapi-generator version

5.3.0 (since at least 5.1.X)

OpenAPI declaration file content or url

Full spec: https://cs.business.stingray.com/assets/swagger.yaml

Relevant snippet:

    post:
      parameters:
        - in: formData
          name: file-en
          type: file
          required: false

Generation Details

--generator-name python

Steps to reproduce

Attempt to upload a file, note that the name sent is file_en and not file-en.

Related issues/PRs

Suggest a fix

I was able to get things working by changing params['file'][param_name] = [param_value] to params['file'][base_name] = [param_value] in api_client.py:745 and api_client.py:749 of my generated client. In the api_client mustache, that would be: https://github.com/OpenAPITools/openapi-generator/blob/b3ec7faa8fc55d89f8df5ccc7e394fb8cb87f299/modules/openapi-generator/src/main/resources/python/api_client.mustache#L765-L769