Connexion error on posting wrong content type to suggest method

[juhoinkinen]

A connexion error occurs if application/json content-type is used in requests to /v1/projects/<project>/suggest method.

For example this curl request produces a 500 response:

curl -X POST -H "Content-Type: application/json" -d '{"documents": [{"text": "content"}]}' http://localhost:5000/v1/projects/tfidf-fi/suggest

And the server logs show:

Exception on /v1/projects/tfidf-fi/suggest [POST]
Traceback (most recent call last):
  File "/home/local/jmminkin/.cache/pypoetry/virtualenvs/annif-ul-EXdhi-py3.8/lib/python3.8/site-packages/flask/app.py", line 2529, in wsgi_app
    response = self.full_dispatch_request()
  File "/home/local/jmminkin/.cache/pypoetry/virtualenvs/annif-ul-EXdhi-py3.8/lib/python3.8/site-packages/flask/app.py", line 1825, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/home/local/jmminkin/.cache/pypoetry/virtualenvs/annif-ul-EXdhi-py3.8/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 "/home/local/jmminkin/.cache/pypoetry/virtualenvs/annif-ul-EXdhi-py3.8/lib/python3.8/site-packages/flask/app.py", line 1823, in full_dispatch_request
    rv = self.dispatch_request()
  File "/home/local/jmminkin/.cache/pypoetry/virtualenvs/annif-ul-EXdhi-py3.8/lib/python3.8/site-packages/flask/app.py", line 1799, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)
  File "/home/local/jmminkin/.cache/pypoetry/virtualenvs/annif-ul-EXdhi-py3.8/lib/python3.8/site-packages/connexion/decorators/decorator.py", line 68, in wrapper
    response = function(request)
  File "/home/local/jmminkin/.cache/pypoetry/virtualenvs/annif-ul-EXdhi-py3.8/lib/python3.8/site-packages/connexion/decorators/uri_parsing.py", line 149, in wrapper
    response = function(request)
  File "/home/local/jmminkin/.cache/pypoetry/virtualenvs/annif-ul-EXdhi-py3.8/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'
INFO:werkzeug:127.0.0.1 - - [27/Apr/2023 11:29:30] "POST /v1/projects/tfidf-fi/suggest HTTP/1.1" 500 -

This is otherwise harmless but the error message is wrong and can be confusing (the above curl command is correct for the suggest-batch method).

This or similar bug has been reported multiple times to connexion, lately in spec-first/connexion#1593.

And it seems that this is fixed by connexion v3, at least the related functionality is modified: spec-first/connexion#1638

Just reporting this now. Let's check this after upgrading to connexion3, which should also get rid of many warnings (#689).

[RobbeSneyders]

Connexion 3 will be released tomorrow.