[python] can't handle 'application/json; charset=UTF-8' when spec lacks charset info

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?

Description

openapi-generator version

openapi-generator-cli 6.2.1
commit : b0ce532
built : 2022-11-01T09:40:00Z
source : https://github.com/openapitools/openapi-generator
docs : https://openapi-generator.tech/

OpenAPI declaration file content or url

https://admin.splunk.com/service/info/specs/v2/openapi.json

Generation Details

openapi-generator generate -g python -o out -i https://admin.splunk.com/service/info/specs/v2/openapi.json --package-name splunkacs --skip-validate-spec

The API call for the following program goes through and in fact fetches the desired json, but the content-type check fails and exception is thrown instead.

Steps to reproduce

import splunkacs
from splunkacs.apis.tags import indexes_api
from splunkacs.model.error import Error
from splunkacs.model.index_response import IndexResponse
from pprint import pprint
# Defining the host is optional and defaults to http://localhost
# See configuration.py for a list of all supported configuration parameters.
configuration = splunkacs.Configuration(
    host = "https://admin.splunk.com"
)


# Configure Bearer authorization (JWT): bearerAuth
configuration.access_token = '<private token>'


# Enter a context with an instance of the API client
with splunkacs.ApiClient(configuration) as api_client:
    # Create an instance of the API class
    api_instance = indexes_api.IndexesApi(api_client)

    # example passing only required values which don't have defaults set
    path_params = {
        'stack': "michmed",
    }
    query_params = {
    }
    try:
        api_response = api_instance.list_indexes(
            path_params=path_params,
            query_params=query_params,
        )
        pprint(api_response)
    except splunkacs.ApiException as e:
        print("Exception when calling IndexesApi->list_indexes: %s\n" % e)
 

The error is as follows,

Traceback (most recent call last):
  File ".../splunkacstest/splunk_cloud_acs_test.py", line 33, in <module>
    api_response = api_instance.list_indexes(
  File "/Users/yyy/.local/lib/python3.10/site-packages/splunkacs-1.0.0-py3.10.egg/splunkacs/paths/stack_adminconfig_v2_indexes/get.py", line 408, in list_indexes
  File "/Users/yyy/.local/lib/python3.10/site-packages/splunkacs-1.0.0-py3.10.egg/splunkacs/paths/stack_adminconfig_v2_indexes/get.py", line 342, in _list_indexes_oapg
  File "/Users/yyy/.local/lib/python3.10/site-packages/splunkacs-1.0.0-py3.10.egg/splunkacs/api_client.py", line 929, in deserialize
splunkacs.exceptions.ApiValueError: Invalid content_type returned. Content_type='application/json; charset=UTF-8' was returned when only {'application/json'} are defined for status_code=200

Suggest a fix

Not sure whether the spec json is flawed or openapi-generator needs to relax the checking.

Start with the generated splunkacs/api_client.py deserialize method and the failing list_indexes call shown in the traceback. Reproduce the response using the linked OpenAPI document, then trace how the Python generator compares the returned Content-Type with the declared media type. Done means the charset-qualified application/json response is handled correctly without breaking content-type validation.