flags.py
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
import re
from distutils.version import LooseVersion
from mozpack.errors import errors
from collections import OrderedDict
class Flag(object):
'''
Class for flags in manifest entries in the form:
"flag" (same as "flag=true")
"flag=yes|true|1"
"flag=no|false|0"
'''
def __init__(self, name):
'''
Initialize a Flag with the given name.
'''
self.name = name
self.value = None
def add_definition(self, definition):
'''
Add a flag value definition. Replaces any previously set value.
'''
if definition == self.name:
self.value = True
return
assert(definition.startswith(self.name))
if definition[len(self.name)] != '=':
return errors.fatal('Malformed flag: %s' % definition)
value = definition[len(self.name) + 1:]
if value in ('yes', 'true', '1', 'no', 'false', '0'):
self.value = value
else:
return errors.fatal('Unknown value in: %s' % definition)
def matches(self, value):
'''
Return whether the flag value matches the given value. The values
are canonicalized for comparison.
'''
if value in ('yes', 'true', '1', True):
return self.value in ('yes', 'true', '1', True)
if value in ('no', 'false', '0', False):
return self.value in ('no', 'false', '0', False, None)
raise RuntimeError('Invalid value: %s' % value)
def __str__(self):
'''
Serialize the flag value in the same form given to the last
add_definition() call.
'''
if self.value is None:
return ''
if self.value is True:
return self.name
return '%s=%s' % (self.name, self.value)
class StringFlag(object):
'''
Class for string flags in manifest entries in the form:
"flag=string"
"flag!=string"
'''
def __init__(self, name):
'''
Initialize a StringFlag with the given name.
'''
self.name = name
self.values = []
def add_definition(self, definition):
'''
Add a string flag definition.
'''
assert(definition.startswith(self.name))
value = definition[len(self.name):]
if value.startswith('='):
self.values.append(('==', value[1:]))
elif value.startswith('!='):
self.values.append(('!=', value[2:]))
else:
return errors.fatal('Malformed flag: %s' % definition)
def matches(self, value):
'''
Return whether one of the string flag definitions matches the given
value.
For example,
flag = StringFlag('foo')
flag.add_definition('foo!=bar')
flag.matches('bar') returns False
flag.matches('qux') returns True
flag = StringFlag('foo')
flag.add_definition('foo=bar')
flag.add_definition('foo=baz')
flag.matches('bar') returns True
flag.matches('baz') returns True
flag.matches('qux') returns False
'''
if not self.values:
return True
for comparison, val in self.values:
if eval('value %s val' % comparison):
return True
return False
def __str__(self):
'''
Serialize the flag definitions in the same form given to each
add_definition() call.
'''
res = []
for comparison, val in self.values:
if comparison == '==':
res.append('%s=%s' % (self.name, val))
else:
res.append('%s!=%s' % (self.name, val))
return ' '.join(res)
class VersionFlag(object):
'''
Class for version flags in manifest entries in the form:
"flag=version"
"flag<=version"
"flag<version"
"flag>=version"
"flag>version"
'''
def __init__(self, name):
'''
Initialize a VersionFlag with the given name.
'''
self.name = name
self.values = []
def add_definition(self, definition):
'''
Add a version flag definition.
'''
assert(definition.startswith(self.name))
value = definition[len(self.name):]
if value.startswith('='):
self.values.append(('==', LooseVersion(value[1:])))
elif len(value) > 1 and value[0] in ['<', '>']:
if value[1] == '=':
if len(value) < 3:
return errors.fatal('Malformed flag: %s' % definition)
self.values.append((value[0:2], LooseVersion(value[2:])))
else:
self.values.append((value[0], LooseVersion(value[1:])))
else:
return errors.fatal('Malformed flag: %s' % definition)
def matches(self, value):
'''
Return whether one of the version flag definitions matches the given
value.
For example,
flag = VersionFlag('foo')
flag.add_definition('foo>=1.0')
flag.matches('1.0') returns True
flag.matches('1.1') returns True
flag.matches('0.9') returns False
flag = VersionFlag('foo')
flag.add_definition('foo>=1.0')
flag.add_definition('foo<0.5')
flag.matches('0.4') returns True
flag.matches('1.0') returns True
flag.matches('0.6') returns False
'''
value = LooseVersion(value)
if not self.values:
return True
for comparison, val in self.values:
if eval('value %s val' % comparison):
return True
return False
def __str__(self):
'''
Serialize the flag definitions in the same form given to each
add_definition() call.
'''
res = []
for comparison, val in self.values:
if comparison == '==':
res.append('%s=%s' % (self.name, val))
else:
res.append('%s%s%s' % (self.name, comparison, val))
return ' '.join(res)
class Flags(OrderedDict):
'''
Class to handle a set of flags definitions given on a single manifest
entry.
'''
FLAGS = {
'application': StringFlag,
'appversion': VersionFlag,
'platformversion': VersionFlag,
'contentaccessible': Flag,
'os': StringFlag,
'osversion': VersionFlag,
'abi': StringFlag,
'platform': Flag,
'xpcnativewrappers': Flag,
'tablet': Flag,
'process': StringFlag,
}
RE = re.compile(r'([!<>=]+)')
def __init__(self, *flags):
'''
Initialize a set of flags given in string form.
flags = Flags('contentaccessible=yes', 'appversion>=3.5')
'''
OrderedDict.__init__(self)
for f in flags:
name = self.RE.split(f)
name = name[0]
if not name in self.FLAGS:
errors.fatal('Unknown flag: %s' % name)
continue
if not name in self:
self[name] = self.FLAGS[name](name)
self[name].add_definition(f)
def __str__(self):
'''
Serialize the set of flags.
'''
return ' '.join(str(self[k]) for k in self)
def match(self, **filter):
'''
Return whether the set of flags match the set of given filters.
flags = Flags('contentaccessible=yes', 'appversion>=3.5',
'application=foo')
flags.match(application='foo') returns True
flags.match(application='foo', appversion='3.5') returns True
flags.match(application='foo', appversion='3.0') returns False
'''
for name, value in filter.iteritems():
if not name in self:
continue
if not self[name].matches(value):
return False
return True
