Problem with python 3.7 and "async" as parameter name

[amoralej]

In python 3.7, async is a reserved keyword [1]. This module is using async as parameter name in different methods and it's failing with syntax errors like (excerpt):

File "/usr/local/lib/python3.7/site-packages/kubernetes/client/apis/admissionregistration_api.py", line 120
async=params.get('async'),
^
SyntaxError: invalid syntax

byte-compiling /tmp/test/usr/local/lib/python3.7/site-packages/kubernetes/client/apis/storage_v1alpha1_api.py to storage_v1alpha1_api.cpython-37.pyc
File "/usr/local/lib/python3.7/site-packages/kubernetes/client/apis/storage_v1alpha1_api.py", line 132
async=params.get('async'),
^
SyntaxError: invalid syntax

byte-compiling /tmp/test/usr/local/lib/python3.7/site-packages/kubernetes/client/apis/autoscaling_api.py to autoscaling_api.cpython-37.pyc
File "/usr/local/lib/python3.7/site-packages/kubernetes/client/apis/autoscaling_api.py", line 120
async=params.get('async'),
^
SyntaxError: invalid syntax

Note that python 3.7 was released recently and some distros (as fedora) will be switching to it.

[1] https://docs.python.org/3.7/whatsnew/3.7.html#summary-release-highlights

[hroncok]

Note that Fedora already is switching to Python 3.7.

[hroncok]

It appears that async is part of the API which makes things hard to fix just by renaming. I have a decorator that might be useful for this (consider it Public Domain or CC0):

from functools import wraps


def deprecated_async(func):
    """A decorator, that let's us keep our old API, but deprecate it"""
    @wraps(func)
    def inner(*args, **kwargs):
        if 'async' in kwargs:
            if 'asynchronous' in kwargs:
                raise ValueError('cannot use both async and asynchronous '
                                 'keyword arguments! the latter obsoletes the first.')
            warnings.warn('async keyword argumnt is deprecated, '
                          'use asynchronous instead', DeprecationWarning)
            kwargs['asynchronous'] = kwargs.pop('async')
        return func(*args, **kwargs)
    return inner


@deprecated_async
def awesome_func(foo, bar, asynchronous=False):
    """People can pass async or asynchronous"""
    ...

[tomplus]

OMG, it looks like a breaking change, btw this part is generated by swagger-codegen.

What does it mean "fedora is switching to p37" ?

[hroncok]

What does it mean "fedora is switching to p37" ?

https://fedoraproject.org/wiki/Changes/Python3.7

[tomplus]

Thanks @hroncok , so Fedora 29 will use it. I though that latest version was switched or something ;)

[hroncok]

But Fedora 29 already needs to use it at this point. From user perspective, this is something form the future, but from ours, it's the current one.

[Chekov2k]

Since Homebrew updated Python to 3.7, my workaround for the Ansible OpenShift and Kubernetes integration was to run this little sed command in the kubernetes/openshift python module directory:

cd /usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/kubernetes
find . -name "*.py" | xargs sed -i '' s/async=para/async_=para/g
cd /usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/openshift
find . -name "*.py" | xargs sed -i '' s/async=para/async_=para/g

Hope it helps someone until the issue is fixed properly

[jbiel]

I ran into this after Homebrew updated Python to 3.7 this morning. @Chekov2k, how are you installing the Kubernetes python package to that directory? If I do a pip install it fails (due to this issue) and kubernetes isn't present in /usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages.

[Chekov2k]

@jbiel I just ran pip3 install kubernetes openshift with a clean install of python3 beforehand

[jbiel]

Thanks @Chekov2k. I ended up using this:

find /usr/local/lib/python3.7/site-packages/kubernetes/	 -name "*.py" | xargs sudo sed -i 's/async=/async_=/g'
sudo sed -i 's/if not async:/if not async_:/' /usr/local/lib/python3.7/site-packages/kubernetes/client/api_client.py

[tomplus]

I opened PR in swagger-codegen and added a simple workaround to gen repository. Next release should support Python 3.7.

If you can't wait I suggest running

find "${OUTPUT_DIR}/client/" -type f -name \*.py -exec sed -i 's/async=/async_req=/g' {} +
find "${OUTPUT_DIR}/client/" -type f -name \*.py -exec sed -i 's/async bool/async_req bool/g' {} +
find "${OUTPUT_DIR}/client/" -type f -name \*.py -exec sed -i "s/'async'/'async_req'/g" {} +
sed -i "s/if not async/if not async_req/g" "${OUTPUT_DIR}/client/api_client.py"

where OUTPUT_DIR is the path to the library.