Compatibility with new PyYAML (version 5.1)

[sirkonst]

Recently PyYAML was released new version 5.1 and tests for my application detects new warning yaml.YAMLLoadWarning for aiohttp-swagger:

Traceback (most recent call last):
  File "/home/_/.pyenv/versions/3.7.0/lib/python3.7/multiprocessing/process.py", line 297, in _bootstrap
    self.run()
  File "/home/_/.pyenv/versions/3.7.0/lib/python3.7/multiprocessing/process.py", line 99, in run
    self._target(*self._args, **self._kwargs)
  File "/home/_/develop/_/_/server.py", line 56, in serve
    web.run_app(app_factory(), port=port)
  File "/home/_/develop/_/.tox/py3.7/lib/python3.7/site-packages/aiohttp/web.py", line 415, in run_app
    reuse_port=reuse_port))
  File "/home/_/.pyenv/versions/3.7.0/lib/python3.7/asyncio/base_events.py", line 568, in run_until_complete
    return future.result()
  File "/home/_/develop/_/.tox/py3.7/lib/python3.7/site-packages/aiohttp/web.py", line 278, in _run_app
    app = await app  # type: ignore
  File "/home/_/develop/_/_/server.py", line 45, in app_factory
    contact='Coffee Team',
  File "/home/_/develop/_/.tox/py3.7/lib/python3.7/site-packages/aiohttp_swagger/__init__.py", line 62, in setup_swagger
    api_version=api_version, title=title, contact=contact
  File "/home/_/develop/_/.tox/py3.7/lib/python3.7/site-packages/aiohttp_swagger/helpers/builders.py", line 71, in generate_doc_from_each_end_point
    swagger = yaml.load(swagger_base)
  File "/home/_/develop/_/.tox/py3.7/lib/python3.7/site-packages/yaml/__init__.py", line 109, in load
    load_warning('load')
  File "/home/_/develop/_/.tox/py3.7/lib/python3.7/site-packages/yaml/__init__.py", line 55, in load_warning
    warnings.warn(message, YAMLLoadWarning, stacklevel=3)
yaml.YAMLLoadWarning: calling yaml.load() without Loader=... is deprecated, as the default Loader is unsafe. Please read https://msg.pyyaml.org/load for full details.

Now, I muted that warning in my tests but hope that aiohttp-swagger fix compatibility.

[nikitagashkov]

For anyone wondering, you can suppress the warning like this:

python -W ignore::yaml.YAMLLoadWarning:aiohttp_swagger.helpers.builders:123
pytest -W ignore::yaml.YAMLLoadWarning:aiohttp_swagger.helpers.builders:123