openstack/oslo.config
Code Issues Proposed changes

Fix config help order to be alphabetical

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Currently The output of --help is in random order. The only way using public
argparse api to control the order of display of --help is to add the arguments
in the sorted order. So added a caching mechanism to collect all the calls
to add_argument and ensure they are sorted before calling argparse's
add_argument. The only other choice if anyone is interested is documented
here which uses the non-public API

http://stackoverflow.com/questions/12268602/sort-argparse-help-alphabetically

Fixes LP# 1185959

Change-Id: I5f934c85fd516e2d87b3ece40142f16c898b04ce
This commit is contained in:
Davanum Srinivas 2013-06-05 12:00:45 -04:00
parent fb2798650d
commit 29513917cb
2 changed files with 72 additions and 14 deletions
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71
oslo/config/cfg.py
View File

@ -601,12 +601,12 @@ class Opt(object):
for opt in self.deprecated_opts:
deprecated_name = self._get_deprecated_cli_name(opt.name,
opt.group)
self._add_to_argparse(container, self.name, self.short,
self._add_to_argparse(parser, container, self.name, self.short,
kwargs, prefix,
self.positional, deprecated_name)
def _add_to_argparse(self, container, name, short, kwargs, prefix='',
positional=False, deprecated_name=None):
def _add_to_argparse(self, parser, container, name, short, kwargs,
prefix='', positional=False, deprecated_name=None):
"""Add an option to an argparse parser or group.
:param container: an argparse._ArgumentGroup object
@ -615,7 +615,6 @@ class Opt(object):
:param kwargs: the keyword arguments for add_argument()
:param prefix: an optional prefix to prepend to the opt name
:param position: whether the optional is a positional CLI argument
:raises: DuplicateOptError if a naming confict is detected
"""
def hyphen(arg):
return arg if not positional else ''
@ -626,10 +625,7 @@ class Opt(object):
if deprecated_name:
args.append(hyphen('--') + deprecated_name)
try:
container.add_argument(*args, **kwargs)
except argparse.ArgumentError as e:
raise DuplicateOptError(e)
parser.add_parser_argument(container, *args, **kwargs)
def _get_argparse_container(self, parser, group):
"""Returns an argparse._ArgumentGroup.
@ -812,8 +808,8 @@ class BoolOpt(Opt):
opt.group,
prefix='no')
kwargs["help"] = "The inverse of --" + self.name
self._add_to_argparse(container, self.name, None, kwargs, prefix,
self.positional, deprecated_name)
self._add_to_argparse(parser, container, self.name, None, kwargs,
prefix, self.positional, deprecated_name)
def _get_argparse_kwargs(self, group, action='store_true', **kwargs):
"""Extends the base argparse keyword dict for boolean options."""
@ -1419,6 +1415,52 @@ class _Namespace(argparse.Namespace):
return values if multi else values[-1]
class _CachedArgumentParser(argparse.ArgumentParser):
"""class for caching/collecting command line arguments.
It also sorts the arguments before intializing the ArgumentParser.
We need to do this since ArgumentParser by default does not sort
the argument options and the only way to influence the order of
arguments in '--help' is to ensure they are added in the sorted
order.
"""
def __init__(self, prog=None, usage=None):
super(_CachedArgumentParser, self).__init__(prog, usage)
self._args_cache = {}
def add_parser_argument(self, container, *args, **kwargs):
values = []
if container in self._args_cache:
values = self._args_cache[container]
values.append({'args': args, 'kwargs': kwargs})
self._args_cache[container] = values
def initialize_parser_arguments(self):
for container, values in self._args_cache.iteritems():
values.sort(key=lambda x: x['args'])
for argument in values:
try:
container.add_argument(*argument['args'],
**argument['kwargs'])
except argparse.ArgumentError as e:
raise DuplicateOptError(e)
self._args_cache = {}
def parse_args(self, args=None, namespace=None):
self.initialize_parser_arguments()
return super(_CachedArgumentParser, self).parse_args(args, namespace)
def print_help(self, file=None):
self.initialize_parser_arguments()
super(_CachedArgumentParser, self).print_help(file)
def print_usage(self, file=None):
self.initialize_parser_arguments()
super(_CachedArgumentParser, self).print_usage(file)
class ConfigOpts(collections.Mapping):
"""Config options which may be set on the command line or in config files.
@ -1449,10 +1491,11 @@ class ConfigOpts(collections.Mapping):
if default_config_files is None:
default_config_files = find_config_files(project, prog)
self._oparser = argparse.ArgumentParser(prog=prog, usage=usage)
self._oparser.add_argument('--version',
action='version',
version=version)
self._oparser = _CachedArgumentParser(prog=prog, usage=usage)
self._oparser.add_parser_argument(self._oparser,
'--version',
action='version',
version=version)
return prog, default_config_files

15
tests/test_cfg.py
View File

@ -130,6 +130,21 @@ class HelpTestCase(BaseTestCase):
self.assertTrue('optional' in f.getvalue())
self.assertTrue('-h, --help' in f.getvalue())
def test_print_sorted_help(self):
f = moves.StringIO()
self.conf.register_cli_opt(cfg.StrOpt('zba'))
self.conf.register_cli_opt(cfg.StrOpt('abc'))
self.conf.register_cli_opt(cfg.StrOpt('ghi'))
self.conf.register_cli_opt(cfg.StrOpt('deb'))
self.conf([])
self.conf.print_help(file=f)
zba = f.getvalue().find('--zba')
abc = f.getvalue().find('--abc')
ghi = f.getvalue().find('--ghi')
deb = f.getvalue().find('--deb')
list = [abc, deb, ghi, zba]
self.assertEquals(sorted(list), list)
class FindConfigFilesTestCase(BaseTestCase):