# Copyright 2012 Red Hat, Inc.
# All Rights Reserved.
+# Copyright 2013 IBM Corp.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
from cinder.openstack.common.gettextutils import _
"""
+import copy
import gettext
+import logging.handlers
import os
+import UserString
_localedir = os.environ.get('cinder'.upper() + '_LOCALEDIR')
_t = gettext.translation('cinder', localedir=_localedir, fallback=True)
gettext.install(domain,
localedir=os.environ.get(domain.upper() + '_LOCALEDIR'),
unicode=True)
+
+
+"""
+Lazy gettext functionality.
+
+The following is an attempt to introduce a deferred way
+to do translations on messages in OpenStack. We attempt to
+override the standard _() function and % (format string) operation
+to build Message objects that can later be translated when we have
+more information. Also included is an example LogHandler that
+translates Messages to an associated locale, effectively allowing
+many logs, each with their own locale.
+"""
+
+
+def get_lazy_gettext(domain):
+ """Assemble and return a lazy gettext function for a given domain.
+
+ Factory method for a project/module to get a lazy gettext function
+ for its own translation domain (i.e. nova, glance, cinder, etc.)
+ """
+
+ def _lazy_gettext(msg):
+ """Create and return a Message object.
+
+ Message encapsulates a string so that we can translate it later when
+ needed.
+ """
+ return Message(msg, domain)
+
+ return _lazy_gettext
+
+
+class Message(UserString.UserString, object):
+ """Class used to encapsulate translatable messages."""
+ def __init__(self, msg, domain):
+ # _msg is the gettext msgid and should never change
+ self._msg = msg
+ self._left_extra_msg = ''
+ self._right_extra_msg = ''
+ self.params = None
+ self.locale = None
+ self.domain = domain
+
+ @property
+ def data(self):
+ # NOTE(mrodden): this should always resolve to a unicode string
+ # that best represents the state of the message currently
+
+ localedir = os.environ.get(self.domain.upper() + '_LOCALEDIR')
+ if self.locale:
+ lang = gettext.translation(self.domain,
+ localedir=localedir,
+ languages=[self.locale],
+ fallback=True)
+ else:
+ # use system locale for translations
+ lang = gettext.translation(self.domain,
+ localedir=localedir,
+ fallback=True)
+
+ full_msg = (self._left_extra_msg +
+ lang.ugettext(self._msg) +
+ self._right_extra_msg)
+
+ if self.params is not None:
+ full_msg = full_msg % self.params
+
+ return unicode(full_msg)
+
+ def _save_parameters(self, other):
+ # we check for None later to see if
+ # we actually have parameters to inject,
+ # so encapsulate if our parameter is actually None
+ if other is None:
+ self.params = (other, )
+ else:
+ self.params = copy.deepcopy(other)
+
+ return self
+
+ # overrides to be more string-like
+ def __unicode__(self):
+ return self.data
+
+ def __str__(self):
+ return self.data.encode('utf-8')
+
+ def __getstate__(self):
+ to_copy = ['_msg', '_right_extra_msg', '_left_extra_msg',
+ 'domain', 'params', 'locale']
+ new_dict = self.__dict__.fromkeys(to_copy)
+ for attr in to_copy:
+ new_dict[attr] = copy.deepcopy(self.__dict__[attr])
+
+ return new_dict
+
+ def __setstate__(self, state):
+ for (k, v) in state.items():
+ setattr(self, k, v)
+
+ # operator overloads
+ def __add__(self, other):
+ copied = copy.deepcopy(self)
+ copied._right_extra_msg += other.__str__()
+ return copied
+
+ def __radd__(self, other):
+ copied = copy.deepcopy(self)
+ copied._left_extra_msg += other.__str__()
+ return copied
+
+ def __mod__(self, other):
+ # do a format string to catch and raise
+ # any possible KeyErrors from missing parameters
+ self.data % other
+ copied = copy.deepcopy(self)
+ return copied._save_parameters(other)
+
+ def __mul__(self, other):
+ return self.data * other
+
+ def __rmul__(self, other):
+ return other * self.data
+
+ def __getitem__(self, key):
+ return self.data[key]
+
+ def __getslice__(self, start, end):
+ return self.data.__getslice__(start, end)
+
+ def __getattribute__(self, name):
+ # NOTE(mrodden): handle lossy operations that we can't deal with yet
+ # These override the UserString implementation, since UserString
+ # uses our __class__ attribute to try and build a new message
+ # after running the inner data string through the operation.
+ # At that point, we have lost the gettext message id and can just
+ # safely resolve to a string instead.
+ ops = ['capitalize', 'center', 'decode', 'encode',
+ 'expandtabs', 'ljust', 'lstrip', 'replace', 'rjust', 'rstrip',
+ 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']
+ if name in ops:
+ return getattr(self.data, name)
+ else:
+ return UserString.UserString.__getattribute__(self, name)
+
+
+class LocaleHandler(logging.Handler):
+ """Handler that can have a locale associated to translate Messages.
+
+ A quick example of how to utilize the Message class above.
+ LocaleHandler takes a locale and a target logging.Handler object
+ to forward LogRecord objects to after translating the internal Message.
+ """
+
+ def __init__(self, locale, target):
+ """Initialize a LocaleHandler
+
+ :param locale: locale to use for translating messages
+ :param target: logging.Handler object to forward
+ LogRecord objects to after translation
+ """
+ logging.Handler.__init__(self)
+ self.locale = locale
+ self.target = target
+
+ def emit(self, record):
+ if isinstance(record.msg, Message):
+ # set the locale and resolve to a string
+ record.msg.locale = self.locale
+
+ self.target.emit(record)
Code Review / openstack-build / cinder-build.git / commitdiff