support multiple content types for the same request body

[gfleischer-meta]

Description

connexion support for sending multiple body types for the same request body.
for example:

• application/x-www-form-urlencoded
• application/json

Expected behavior

Connexion accepts multiple content types for the same request

Actual behavior

will work for 'application/x-www-form-urlencoded' because it is the first content type in the request
but for 'application/json' will fail with an Erro and a warning:
WARNING this operation accepts multiple content types, using application/x-www-form-urlencoded

Traceback (most recent call last):
File "/usr/local/lib/python3.8/site-packages/flask/app.py", line 2463, in wsgi_app
```     response = self.full_dispatch_request()
```   File "/usr/local/lib/python3.8/site-packages/flask/app.py", line 1760, in full_dispatch_request
```     rv = self.handle_user_exception(e)
```   File "/usr/local/lib/python3.8/site-packages/flask_cors/extension.py", line 165, in wrapped_function
```     return cors_after_request(app.make_response(f(*args, **kwargs)))
```   File "/usr/local/lib/python3.8/site-packages/flask/app.py", line 1758, in full_dispatch_request
```     rv = self.dispatch_request()
```   File "/usr/local/lib/python3.8/site-packages/flask/app.py", line 1734, in dispatch_request
```     return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)
```   File "/usr/local/lib/python3.8/site-packages/connexion/decorators/decorator.py", line 68, in wrapper
```     response = function(request)
```   File "/usr/local/lib/python3.8/site-packages/connexion/decorators/uri_parsing.py", line 149, in wrapper
```     response = function(request)
```   File "/usr/local/lib/python3.8/site-packages/connexion/decorators/validation.py", line 173, in wrapper
```     data.update(dict.fromkeys(request.files, ''))  # validator expects string..
``` AttributeError: 'bytes' object has no attribute 'update'

if the the order is switched(content type 'application/json' is first and then 'application/x-www-form-urlencoded')
it will work for 'application/json' and for 'application/x-www-form-urlencoded' it will return an empty bytes object with the warning:
WARNING this operation accepts multiple content types, using application/json

Additional info:

I saw that there was a commit to try and fix this but it was closed:
#1435

and a commit to support this issue that was merged but not tagged yet in a release:
#1588

when will this issue be fixed?
is it expected to be released soon?
thanks in advance

Steps to reproduce

a request body for example I would expect to work:

        description: example
        required: true
        content:
          application/x-www-form-urlencoded:
            schema:
              x-body-name: new_tmp
              type: object
              properties:
                name:
                  type: string
                age:
                  type: integer
          application/json:
            schema:
              x-body-name: new_tmp
              type: object
              properties:
                name:
                  type: string
                age:
                  type: integer

Python 3.8.16
Connexion version: 2.14.2

[RobbeSneyders]

Hi @gfleischer-meta this is indeed fixed in the PR you linked, but not yet released as this is part of a major refactoring towards version 3.0. We're done with most feature work with 3.0, now just working on expanding our test suite for the new AsyncApp, after which we'll release a first alpha version. I hope to do this in the next weeks.