charm pep8 lint checks fail

[Ryan Beisner]

At master from the original author, py3 lint/pep8 tests are failing:

pep8 installed: attrs==19.1.0,certifi==2019.6.16,chardet==3.0.4,charmhelpers==0.19.15,charms.openstack==0.0.1.dev1,charms.reactive==1.2.1,cliff==2.15.0,cmd2==0.9.14,colorama==0.4.1,coverage==4.5.3,extras==1.0.0,fixtures==3.0.0,flake8==2.4.1,future==0.17.1,idna==2.8,Jinja2==2.10.1,linecache2==1.0.0,MarkupSafe==1.1.1,mccabe==0.3.1,mock==3.0.5,netaddr==0.7.19,nose==1.3.7,pbr==5.4.0,pep8==1.7.1,pkg-resources==0.0.0,prettytable==0.7.2,pyaml==19.4.1,pyflakes==0.8.1,pyparsing==2.4.0,pyperclip==1.7.0,python-mimeparse==1.6.0,python-subunit==1.3.0,PyYAML==5.1.1,requests==2.22.0,six==1.12.0,stestr==2.3.1,stevedore==1.30.1,Tempita==0.5.2,testtools==2.3.0,traceback2==1.4.0,unittest2==1.1.0,urllib3==1.25.3,voluptuous==0.11.5,wcwidth==0.1.7
pep8 run-test-pre: PYTHONHASHSEED='0'
pep8 runtests: commands[0] | flake8 src unit_tests
/home/beisner/git/charm-cinder-purestorage/.tox/pep8/lib/python3.7/site-packages/pep8.py:110: FutureWarning: Possible nested set at position 1
  EXTRANEOUS_WHITESPACE_REGEX = re.compile(r'[[({] | []}),;:]')
/home/beisner/git/charm-cinder-purestorage/.tox/pep8/lib/python3.7/site-packages/flake8/engine.py:33: PkgResourcesDeprecationWarning: Parameters to load are deprecated. Call .resolve and .require separately.
  checker = entry.load(require=False)
src/reactive/cinder_purestorage_handlers.py:29:1: E302 expected 2 blank lines, found 1
src/reactive/cinder_purestorage_handlers.py:31:61: F811 redefinition of unused 'charm' from line 20
src/lib/charm/openstack/cinder_purestorage.py:2:47: E261 at least two spaces before inline comment
src/lib/charm/openstack/cinder_purestorage.py:2:54: W291 trailing whitespace
src/lib/charm/openstack/cinder_purestorage.py:6:1: E302 expected 2 blank lines, found 1
src/lib/charm/openstack/cinder_purestorage.py:16:13: E126 continuation line over-indented for hanging indent
src/lib/charm/openstack/cinder_purestorage.py:16:24: F821 undefined name 'self'
src/lib/charm/openstack/cinder_purestorage.py:17:32: F821 undefined name 'self'
src/lib/charm/openstack/cinder_purestorage.py:24:61: F821 undefined name 'service_name'
src/lib/charm/openstack/cinder_purestorage.py:32:1: E302 expected 2 blank lines, found 1
unit_tests/test_lib_charm_openstack_cinder_purestorage.py:47:46: E261 at least two spaces before inline comment
src/tests/tests_cinder_purestorage.py:26:1: E302 expected 2 blank lines, found 1
src/tests/tests_cinder_purestorage.py:44:80: E501 line too long (80 > 79 characters)
src/tests/tests_cinder_purestorage.py:59:10: E111 indentation is not a multiple of four
src/tests/tests_cinder_purestorage.py:60:10: E111 indentation is not a multiple of four
src/tests/tests_cinder_purestorage.py:63:10: E111 indentation is not a multiple of four
src/tests/tests_cinder_purestorage.py:67:10: E111 indentation is not a multiple of four
src/tests/tests_cinder_purestorage.py:68:10: E111 indentation is not a multiple of four
src/tests/tests_cinder_purestorage.py:71:10: E111 indentation is not a multiple of four
src/tests/tests_cinder_purestorage.py:72:1: W391 blank line at end of file
ERROR: InvocationError for command '/home/beisner/git/charm-cinder-purestorage/.tox/pep8/bin/flake8 src unit_tests' (exited with code 1)
___________________________________ summary ____________________________________
ERROR: pep8: commands failed

[Ryan Beisner (1chb1n)]

WIP @ https://github.com/openstack-charmers/charm-cinder-purestorage/pull/4

[Ryan Beisner (1chb1n)]

Take note: removig "noqa" markers, which may surface more serious issues, but please do not re-ntroduce those lint skip statements.

[Ryan Beisner (1chb1n)]

We've taken this to a point where the obvious pep8 violations are resolved. The remaining errors are likely design issues which will need to be addressed after discussion with the author/maintainer. The following remaining lint errors are echoed in the unit tests and in deploy-time hook errors.

beisner@rby:~/git/charm-cinder-purestorage$ tox -e pep8
pep8 installed: attrs==19.1.0,certifi==2019.6.16,chardet==3.0.4,charmhelpers==0.19.15,charms.openstack==0.0.1.dev1,charms.reactive==1.2.1,cliff==2.15.0,cmd2==0.9.14,colorama==0.4.1,coverage==4.5.3,extras==1.0.0,fixtures==3.0.0,flake8==2.4.1,future==0.17.1,idna==2.8,Jinja2==2.10.1,linecache2==1.0.0,MarkupSafe==1.1.1,mccabe==0.3.1,mock==3.0.5,netaddr==0.7.19,nose==1.3.7,pbr==5.4.0,pep8==1.7.1,pkg-resources==0.0.0,prettytable==0.7.2,pyaml==19.4.1,pyflakes==0.8.1,pyparsing==2.4.0,pyperclip==1.7.0,python-mimeparse==1.6.0,python-subunit==1.3.0,PyYAML==5.1.1,requests==2.22.0,six==1.12.0,stestr==2.3.1,stevedore==1.30.1,Tempita==0.5.2,testtools==2.3.0,traceback2==1.4.0,unittest2==1.1.0,urllib3==1.25.3,voluptuous==0.11.5,wcwidth==0.1.7
pep8 run-test-pre: PYTHONHASHSEED='0'
pep8 runtests: commands[0] | flake8 src unit_tests
/home/beisner/git/charm-cinder-purestorage/.tox/pep8/lib/python3.7/site-packages/pep8.py:110: FutureWarning: Possible nested set at position 1
  EXTRANEOUS_WHITESPACE_REGEX = re.compile(r'[[({] | []}),;:]')
/home/beisner/git/charm-cinder-purestorage/.tox/pep8/lib/python3.7/site-packages/flake8/engine.py:33: PkgResourcesDeprecationWarning: Parameters to load are deprecated. Call .resolve and .require separately.
  checker = entry.load(require=False)
src/reactive/cinder_purestorage_handlers.py:20:1: F401 'charm' imported but unused
src/reactive/cinder_purestorage_handlers.py:32:61: F811 redefinition of unused 'charm' from line 20
src/lib/charm/openstack/cinder_purestorage.py:2:1: F401 'ch_hookenv' imported but unused
src/lib/charm/openstack/cinder_purestorage.py:17:20: F821 undefined name 'self'
src/lib/charm/openstack/cinder_purestorage.py:18:28: F821 undefined name 'self'
src/lib/charm/openstack/cinder_purestorage.py:26:61: F821 undefined name 'service_name'
unit_tests/test_lib_charm_openstack_cinder_purestorage.py:47:9: F841 local variable 'config' is assigned to but never used
ERROR: InvocationError for command '/home/beisner/git/charm-cinder-purestorage/.tox/pep8/bin/flake8 src unit_tests' (exited with code 1)
________________________________________________________________________________________ summary _________________________________________________________________________________________
ERROR: pep8: commands failed