#!/usr/bin/env python
# "Required options" with Optik, version 2:
# extend Option and add a 'required' attribute;
# extend OptionParser to ensure that required options
# are present after parsing.
import optik
class Option (optik.Option):
ATTRS = optik.Option.ATTRS + ['required']
def _check_required (self):
if self.required and not self.takes_value():
raise OptionError(
"required flag set for option that doesn't take a value",
self)
# Make sure _check_required() is called from the constructor!
CHECK_METHODS = optik.Option.CHECK_METHODS + [_check_required]
def process (self, opt, value, values, parser):
optik.Option.process(self, opt, value, values, parser)
parser.option_seen[self] = 1
class OptionParser (optik.OptionParser):
def _init_parsing_state (self):
optik.OptionParser._init_parsing_state(self)
self.option_seen = {}
def check_values (self, values, args):
for option in self.option_list:
if (isinstance(option, Option) and
option.required and
not self.option_seen.has_key(option)):
self.error("%s not supplied" % option)
return (values, args)
parser = OptionParser(option_list=[
Option("-v", action="count", dest="verbose"),
Option("-f", "--file", required=1)])
(options, args) = parser.parse_args()
print "verbose:", options.verbose
print "file:", options.file
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