From 8e76231fda7ec828856a9fca32f37ff9089611a8 Mon Sep 17 00:00:00 2001 From: "Luis A. Garcia" Date: Mon, 8 Jul 2013 23:03:20 +0000 Subject: [PATCH] Sync gettextutils from oslo Bring in the necessary code for handling cinder translations Partially implements bp user-locale-api Change-Id: Ibcf087c0f099262b90c115a155fdef619d3c5851 --- cinder/openstack/common/gettextutils.py | 176 ++++++++++++++++++++++++ 1 file changed, 176 insertions(+) diff --git a/cinder/openstack/common/gettextutils.py b/cinder/openstack/common/gettextutils.py index 5c0540b43d4..ba04f854125 100644 --- a/cinder/openstack/common/gettextutils.py +++ b/cinder/openstack/common/gettextutils.py @@ -2,6 +2,7 @@ # 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 @@ -23,8 +24,11 @@ Usual usage in an openstack.common module: 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) @@ -48,3 +52,175 @@ def install(domain): 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)