diff options
Diffstat (limited to 'ceilometerclient/openstack/common/gettextutils.py')
| -rw-r--r-- | ceilometerclient/openstack/common/gettextutils.py | 592 |
1 files changed, 350 insertions, 242 deletions
diff --git a/ceilometerclient/openstack/common/gettextutils.py b/ceilometerclient/openstack/common/gettextutils.py index c28d730..75082d7 100644 --- a/ceilometerclient/openstack/common/gettextutils.py +++ b/ceilometerclient/openstack/common/gettextutils.py @@ -24,24 +24,122 @@ Usual usage in an openstack.common module: import copy import gettext -import logging +import locale +from logging import handlers import os -import re -try: - import UserString as _userString -except ImportError: - import collections as _userString from babel import localedata import six -_localedir = os.environ.get('ceilometerclient'.upper() + '_LOCALEDIR') -_t = gettext.translation('ceilometerclient', localedir=_localedir, fallback=True) - _AVAILABLE_LANGUAGES = {} + +# FIXME(dhellmann): Remove this when moving to oslo.i18n. USE_LAZY = False +class TranslatorFactory(object): + """Create translator functions + """ + + def __init__(self, domain, localedir=None): + """Establish a set of translation functions for the domain. + + :param domain: Name of translation domain, + specifying a message catalog. + :type domain: str + :param lazy: Delays translation until a message is emitted. + Defaults to False. + :type lazy: Boolean + :param localedir: Directory with translation catalogs. + :type localedir: str + """ + self.domain = domain + if localedir is None: + localedir = os.environ.get(domain.upper() + '_LOCALEDIR') + self.localedir = localedir + + def _make_translation_func(self, domain=None): + """Return a new translation function ready for use. + + Takes into account whether or not lazy translation is being + done. + + The domain can be specified to override the default from the + factory, but the localedir from the factory is always used + because we assume the log-level translation catalogs are + installed in the same directory as the main application + catalog. + + """ + if domain is None: + domain = self.domain + t = gettext.translation(domain, + localedir=self.localedir, + fallback=True) + # Use the appropriate method of the translation object based + # on the python version. + m = t.gettext if six.PY3 else t.ugettext + + def f(msg): + """oslo.i18n.gettextutils translation function.""" + if USE_LAZY: + return Message(msg, domain=domain) + return m(msg) + return f + + @property + def primary(self): + "The default translation function." + return self._make_translation_func() + + def _make_log_translation_func(self, level): + return self._make_translation_func(self.domain + '-log-' + level) + + @property + def log_info(self): + "Translate info-level log messages." + return self._make_log_translation_func('info') + + @property + def log_warning(self): + "Translate warning-level log messages." + return self._make_log_translation_func('warning') + + @property + def log_error(self): + "Translate error-level log messages." + return self._make_log_translation_func('error') + + @property + def log_critical(self): + "Translate critical-level log messages." + return self._make_log_translation_func('critical') + + +# NOTE(dhellmann): When this module moves out of the incubator into +# oslo.i18n, these global variables can be moved to an integration +# module within each application. + +# Create the global translation functions. +_translators = TranslatorFactory('ceilometerclient') + +# The primary translation function using the well-known name "_" +_ = _translators.primary + +# Translators for log levels. +# +# The abbreviated names are meant to reflect the usual use of a short +# name like '_'. The "L" is for "log" and the other letter comes from +# the level. +_LI = _translators.log_info +_LW = _translators.log_warning +_LE = _translators.log_error +_LC = _translators.log_critical + +# NOTE(dhellmann): End of globals that will move to the application's +# integration module. + + def enable_lazy(): """Convenience function for configuring _() to use lazy gettext @@ -54,16 +152,7 @@ def enable_lazy(): USE_LAZY = True -def _(msg): - if USE_LAZY: - return Message(msg, 'ceilometerclient') - else: - if six.PY3: - return _t.gettext(msg) - return _t.ugettext(msg) - - -def install(domain, lazy=False): +def install(domain): """Install a _() function using the given translation domain. Given a translation domain, install a _() function using gettext's @@ -74,226 +163,155 @@ def install(domain, lazy=False): a translation-domain-specific environment variable (e.g. NOVA_LOCALEDIR). + Note that to enable lazy translation, enable_lazy must be + called. + :param domain: the translation domain - :param lazy: indicates whether or not to install the lazy _() function. - The lazy _() introduces a way to do deferred translation - of messages by installing a _ that builds Message objects, - instead of strings, which can then be lazily translated into - any available locale. """ - if lazy: - # NOTE(mrodden): Lazy gettext functionality. - # - # The following introduces a deferred way to do translations on - # messages in OpenStack. We override the standard _() function - # and % (format string) operation to build Message objects that can - # later be translated when we have more information. - # - # Also included below is an example LocaleHandler that translates - # Messages to an associated locale, effectively allowing many logs, - # each with their own locale. - - def _lazy_gettext(msg): - """Create and return a Message object. - - Lazy gettext function for a given domain, it is a factory method - for a project/module to get a lazy gettext function for its own - translation domain (i.e. nova, glance, cinder, etc.) - - Message encapsulates a string so that we can translate - it later when needed. - """ - return Message(msg, domain) - - from six import moves - moves.builtins.__dict__['_'] = _lazy_gettext - else: - localedir = '%s_LOCALEDIR' % domain.upper() - if six.PY3: - gettext.install(domain, - localedir=os.environ.get(localedir)) - else: - gettext.install(domain, - localedir=os.environ.get(localedir), - unicode=True) - - -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._locale = None - self.params = None - self.domain = domain + from six import moves + tf = TranslatorFactory(domain) + moves.builtins.__dict__['_'] = tf.primary - @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) - if six.PY3: - ugettext = lang.gettext - else: - ugettext = lang.ugettext +class Message(six.text_type): + """A Message object is a unicode object that can be translated. - full_msg = (self._left_extra_msg + - ugettext(self._msg) + - self._right_extra_msg) + Translation of Message is done explicitly using the translate() method. + For all non-translation intents and purposes, a Message is simply unicode, + and can be treated as such. + """ - if self.params is not None: - full_msg = full_msg % self.params + def __new__(cls, msgid, msgtext=None, params=None, + domain='ceilometerclient', *args): + """Create a new Message object. - return six.text_type(full_msg) + In order for translation to work gettext requires a message ID, this + msgid will be used as the base unicode text. It is also possible + for the msgid and the base unicode text to be different by passing + the msgtext parameter. + """ + # If the base msgtext is not given, we use the default translation + # of the msgid (which is in English) just in case the system locale is + # not English, so that the base text will be in that locale by default. + if not msgtext: + msgtext = Message._translate_msgid(msgid, domain) + # We want to initialize the parent unicode with the actual object that + # would have been plain unicode if 'Message' was not enabled. + msg = super(Message, cls).__new__(cls, msgtext) + msg.msgid = msgid + msg.domain = domain + msg.params = params + return msg + + def translate(self, desired_locale=None): + """Translate this message to the desired locale. + + :param desired_locale: The desired locale to translate the message to, + if no locale is provided the message will be + translated to the system's default locale. + + :returns: the translated message in unicode + """ - @property - def locale(self): - return self._locale - - @locale.setter - def locale(self, value): - self._locale = value - if not self.params: - return - - # This Message object may have been constructed with one or more - # Message objects as substitution parameters, given as a single - # Message, or a tuple or Map containing some, so when setting the - # locale for this Message we need to set it for those Messages too. - if isinstance(self.params, Message): - self.params.locale = value - return - if isinstance(self.params, tuple): - for param in self.params: - if isinstance(param, Message): - param.locale = value - return - if isinstance(self.params, dict): - for param in self.params.values(): - if isinstance(param, Message): - param.locale = value - - def _save_dictionary_parameter(self, dict_param): - full_msg = self.data - # look for %(blah) fields in string; - # ignore %% and deal with the - # case where % is first character on the line - keys = re.findall('(?:[^%]|^)?%\((\w*)\)[a-z]', full_msg) - - # if we don't find any %(blah) blocks but have a %s - if not keys and re.findall('(?:[^%]|^)%[a-z]', full_msg): - # apparently the full dictionary is the parameter - params = copy.deepcopy(dict_param) + translated_message = Message._translate_msgid(self.msgid, + self.domain, + desired_locale) + if self.params is None: + # No need for more translation + return translated_message + + # This Message object may have been formatted with one or more + # Message objects as substitution arguments, given either as a single + # argument, part of a tuple, or as one or more values in a dictionary. + # When translating this Message we need to translate those Messages too + translated_params = _translate_args(self.params, desired_locale) + + translated_message = translated_message % translated_params + + return translated_message + + @staticmethod + def _translate_msgid(msgid, domain, desired_locale=None): + if not desired_locale: + system_locale = locale.getdefaultlocale() + # If the system locale is not available to the runtime use English + if not system_locale[0]: + desired_locale = 'en_US' + else: + desired_locale = system_locale[0] + + locale_dir = os.environ.get(domain.upper() + '_LOCALEDIR') + lang = gettext.translation(domain, + localedir=locale_dir, + languages=[desired_locale], + fallback=True) + if six.PY3: + translator = lang.gettext else: - params = {} - for key in keys: - try: - params[key] = copy.deepcopy(dict_param[key]) - except TypeError: - # cast uncopyable thing to unicode string - params[key] = six.text_type(dict_param[key]) + translator = lang.ugettext - return params + translated_message = translator(msgid) + return translated_message - 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 + def __mod__(self, other): + # When we mod a Message we want the actual operation to be performed + # by the parent class (i.e. unicode()), the only thing we do here is + # save the original msgid and the parameters in case of a translation + params = self._sanitize_mod_params(other) + unicode_mod = super(Message, self).__mod__(params) + modded = Message(self.msgid, + msgtext=unicode_mod, + params=params, + domain=self.domain) + return modded + + def _sanitize_mod_params(self, other): + """Sanitize the object being modded with this Message. + + - Add support for modding 'None' so translation supports it + - Trim the modded object, which can be a large dictionary, to only + those keys that would actually be used in a translation + - Snapshot the object being modded, in case the message is + translated, it will be used as it was when the Message was created + """ if other is None: - self.params = (other, ) + params = (other,) elif isinstance(other, dict): - self.params = self._save_dictionary_parameter(other) + # Merge the dictionaries + # Copy each item in case one does not support deep copy. + params = {} + if isinstance(self.params, dict): + for key, val in self.params.items(): + params[key] = self._copy_param(val) + for key, val in other.items(): + params[key] = self._copy_param(val) else: - # fallback to casting to unicode, - # this will handle the problematic python code-like - # objects that cannot be deep-copied - try: - self.params = copy.deepcopy(other) - except TypeError: - self.params = six.text_type(other) - - return self - - # overrides to be more string-like - def __unicode__(self): - return self.data - - def __str__(self): - if six.PY3: - return self.__unicode__() - 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 + params = self._copy_param(other) + return params - def __setstate__(self, state): - for (k, v) in state.items(): - setattr(self, k, v) + def _copy_param(self, param): + try: + return copy.deepcopy(param) + except Exception: + # Fallback to casting to unicode this will handle the + # python code-like objects that can't be deep-copied + return six.text_type(param) - # operator overloads def __add__(self, other): - copied = copy.deepcopy(self) - copied._right_extra_msg += other.__str__() - return copied + msg = _('Message objects do not support addition.') + raise TypeError(msg) def __radd__(self, other): - copied = copy.deepcopy(self) - copied._left_extra_msg += other.__str__() - return copied + return self.__add__(other) - 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) + if six.PY2: + def __str__(self): + # NOTE(luisg): Logging in python 2.6 tries to str() log records, + # and it expects specifically a UnicodeError in order to proceed. + msg = _('Message objects do not support str() because they may ' + 'contain non-ascii characters. ' + 'Please use unicode() or translate() instead.') + raise UnicodeError(msg) def get_available_languages(domain): @@ -319,53 +337,143 @@ def get_available_languages(domain): list_identifiers = (getattr(localedata, 'list', None) or getattr(localedata, 'locale_identifiers')) locale_identifiers = list_identifiers() + for i in locale_identifiers: if find(i) is not None: language_list.append(i) + + # NOTE(luisg): Babel>=1.0,<1.3 has a bug where some OpenStack supported + # locales (e.g. 'zh_CN', and 'zh_TW') aren't supported even though they + # are perfectly legitimate locales: + # https://github.com/mitsuhiko/babel/issues/37 + # In Babel 1.3 they fixed the bug and they support these locales, but + # they are still not explicitly "listed" by locale_identifiers(). + # That is why we add the locales here explicitly if necessary so that + # they are listed as supported. + aliases = {'zh': 'zh_CN', + 'zh_Hant_HK': 'zh_HK', + 'zh_Hant': 'zh_TW', + 'fil': 'tl_PH'} + for (locale_, alias) in six.iteritems(aliases): + if locale_ in language_list and alias not in language_list: + language_list.append(alias) + _AVAILABLE_LANGUAGES[domain] = language_list return copy.copy(language_list) -def get_localized_message(message, user_locale): - """Gets a localized version of the given message in the given locale. +def translate(obj, desired_locale=None): + """Gets the translated unicode representation of the given object. - If the message is not a Message object the message is returned as-is. - If the locale is None the message is translated to the default locale. + If the object is not translatable it is returned as-is. + If the locale is None the object is translated to the system locale. - :returns: the translated message in unicode, or the original message if + :param obj: the object to translate + :param desired_locale: the locale to translate the message to, if None the + default system locale will be used + :returns: the translated object in unicode, or the original object if it could not be translated """ - translated = message + message = obj + if not isinstance(message, Message): + # If the object to translate is not already translatable, + # let's first get its unicode representation + message = six.text_type(obj) if isinstance(message, Message): - original_locale = message.locale - message.locale = user_locale - translated = six.text_type(message) - message.locale = original_locale - return translated + # Even after unicoding() we still need to check if we are + # running with translatable unicode before translating + return message.translate(desired_locale) + return obj + +def _translate_args(args, desired_locale=None): + """Translates all the translatable elements of the given arguments object. -class LocaleHandler(logging.Handler): - """Handler that can have a locale associated to translate Messages. + This method is used for translating the translatable values in method + arguments which include values of tuples or dictionaries. + If the object is not a tuple or a dictionary the object itself is + translated if it is translatable. - 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. + If the locale is None the object is translated to the system locale. + + :param args: the args to translate + :param desired_locale: the locale to translate the args to, if None the + default system locale will be used + :returns: a new args object with the translated contents of the original """ + if isinstance(args, tuple): + return tuple(translate(v, desired_locale) for v in args) + if isinstance(args, dict): + translated_dict = {} + for (k, v) in six.iteritems(args): + translated_v = translate(v, desired_locale) + translated_dict[k] = translated_v + return translated_dict + return translate(args, desired_locale) + - def __init__(self, locale, target): - """Initialize a LocaleHandler +class TranslationHandler(handlers.MemoryHandler): + """Handler that translates records before logging them. + + The TranslationHandler takes a locale and a target logging.Handler object + to forward LogRecord objects to after translating them. This handler + depends on Message objects being logged, instead of regular strings. + + The handler can be configured declaratively in the logging.conf as follows: + + [handlers] + keys = translatedlog, translator + + [handler_translatedlog] + class = handlers.WatchedFileHandler + args = ('/var/log/api-localized.log',) + formatter = context + + [handler_translator] + class = openstack.common.log.TranslationHandler + target = translatedlog + args = ('zh_CN',) + + If the specified locale is not available in the system, the handler will + log in the default locale. + """ + + def __init__(self, locale=None, target=None): + """Initialize a TranslationHandler :param locale: locale to use for translating messages :param target: logging.Handler object to forward LogRecord objects to after translation """ - logging.Handler.__init__(self) + # NOTE(luisg): In order to allow this handler to be a wrapper for + # other handlers, such as a FileHandler, and still be able to + # configure it using logging.conf, this handler has to extend + # MemoryHandler because only the MemoryHandlers' logging.conf + # parsing is implemented such that it accepts a target handler. + handlers.MemoryHandler.__init__(self, capacity=0, target=target) self.locale = locale - self.target = target + + def setFormatter(self, fmt): + self.target.setFormatter(fmt) def emit(self, record): - if isinstance(record.msg, Message): - # set the locale and resolve to a string - record.msg.locale = self.locale + # We save the message from the original record to restore it + # after translation, so other handlers are not affected by this + original_msg = record.msg + original_args = record.args + + try: + self._translate_and_log_record(record) + finally: + record.msg = original_msg + record.args = original_args + + def _translate_and_log_record(self, record): + record.msg = translate(record.msg, self.locale) + + # In addition to translating the message, we also need to translate + # arguments that were passed to the log method that were not part + # of the main message e.g., log.info(_('Some message %s'), this_one)) + record.args = _translate_args(record.args, self.locale) self.target.emit(record) |