Merge "Run unittest with python 3.3"0.1.1

1 files changed, 369 insertions, 8 deletions

diff --git a/ironicclient/openstack/common/gettextutils.py b/ironicclient/openstack/common/gettextutils.py
index 5eca25e..9919d42 100644
--- a/ironicclient/openstack/common/gettextutils.py
+++ b/ironicclient/openstack/common/gettextutils.py
@@ -1,6 +1,5 @@
-# vim: tabstop=4 shiftwidth=4 softtabstop=4
-
 # Copyright 2012 Red Hat, Inc.
+# Copyright 2013 IBM Corp.
 # All Rights Reserved.
 #
 #    Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -20,21 +19,48 @@ gettext for openstack-common modules.
 
 Usual usage in an openstack.common module:
 
-    from ironic.openstack.common.gettextutils import _
+    from ironicclient.openstack.common.gettextutils import _
 """
 
+import copy
 import gettext
+import locale
+from logging import handlers
 import os
+import re
+
+from babel import localedata
+import six
 
 _localedir = os.environ.get('ironicclient'.upper() + '_LOCALEDIR')
 _t = gettext.translation('ironicclient', localedir=_localedir, fallback=True)
 
+_AVAILABLE_LANGUAGES = {}
+USE_LAZY = False
+
+
+def enable_lazy():
+    """Convenience function for configuring _() to use lazy gettext
+
+    Call this at the start of execution to enable the gettextutils._
+    function to use lazy gettext functionality. This is useful if
+    your project is importing _ directly instead of using the
+    gettextutils.install() way of importing the _ function.
+    """
+    global USE_LAZY
+    USE_LAZY = True
+
 
 def _(msg):
-    return _t.ugettext(msg)
+    if USE_LAZY:
+        return Message(msg, domain='ironicclient')
+    else:
+        if six.PY3:
+            return _t.gettext(msg)
+        return _t.ugettext(msg)
 
 
-def install(domain):
+def install(domain, lazy=False):
     """Install a _() function using the given translation domain.
 
     Given a translation domain, install a _() function using gettext's
@@ -44,7 +70,342 @@ def install(domain):
     overriding the default localedir (e.g. /usr/share/locale) using
     a translation-domain-specific environment variable (e.g.
     NOVA_LOCALEDIR).
+
+    :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.
+        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=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(six.text_type):
+    """A Message object is a unicode object that can be translated.
+
+    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.
+    """
+
+    def __new__(cls, msgid, msgtext=None, params=None, domain='ironicclient', *args):
+        """Create a new Message object.
+
+        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
+        """
+
+        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:
+            translator = lang.ugettext
+
+        translated_message = translator(msgid)
+        return translated_message
+
+    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
+        unicode_mod = super(Message, self).__mod__(other)
+        modded = Message(self.msgid,
+                         msgtext=unicode_mod,
+                         params=self._sanitize_mod_params(other),
+                         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:
+            params = (other,)
+        elif isinstance(other, dict):
+            params = self._trim_dictionary_parameters(other)
+        else:
+            params = self._copy_param(other)
+        return params
+
+    def _trim_dictionary_parameters(self, dict_param):
+        """Return a dict that only has matching entries in the msgid."""
+        # NOTE(luisg): Here we trim down the dictionary passed as parameters
+        # to avoid carrying a lot of unnecessary weight around in the message
+        # object, for example if someone passes in Message() % locals() but
+        # only some params are used, and additionally we prevent errors for
+        # non-deepcopyable objects by unicoding() them.
+
+        # Look for %(param) keys in msgid;
+        # Skip %% and deal with the case where % is first character on the line
+        keys = re.findall('(?:[^%]|^)?%\((\w*)\)[a-z]', self.msgid)
+
+        # If we don't find any %(param) keys but have a %s
+        if not keys and re.findall('(?:[^%]|^)%[a-z]', self.msgid):
+            # Apparently the full dictionary is the parameter
+            params = self._copy_param(dict_param)
+        else:
+            params = {}
+            for key in keys:
+                params[key] = self._copy_param(dict_param[key])
+
+        return params
+
+    def _copy_param(self, param):
+        try:
+            return copy.deepcopy(param)
+        except TypeError:
+            # Fallback to casting to unicode this will handle the
+            # python code-like objects that can't be deep-copied
+            return six.text_type(param)
+
+    def __add__(self, other):
+        msg = _('Message objects do not support addition.')
+        raise TypeError(msg)
+
+    def __radd__(self, other):
+        return self.__add__(other)
+
+    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):
+    """Lists the available languages for the given translation domain.
+
+    :param domain: the domain to get languages for
+    """
+    if domain in _AVAILABLE_LANGUAGES:
+        return copy.copy(_AVAILABLE_LANGUAGES[domain])
+
+    localedir = '%s_LOCALEDIR' % domain.upper()
+    find = lambda x: gettext.find(domain,
+                                  localedir=os.environ.get(localedir),
+                                  languages=[x])
+
+    # NOTE(mrodden): en_US should always be available (and first in case
+    # order matters) since our in-line message strings are en_US
+    language_list = ['en_US']
+    # NOTE(luisg): Babel <1.0 used a function called list(), which was
+    # renamed to locale_identifiers() in >=1.0, the requirements master list
+    # requires >=0.9.6, uncapped, so defensively work with both. We can remove
+    # this check when the master list updates to >=1.0, and update all projects
+    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)
+    _AVAILABLE_LANGUAGES[domain] = language_list
+    return copy.copy(language_list)
+
+
+def translate(obj, desired_locale=None):
+    """Gets the translated unicode representation of the given object.
+
+    If the object is not translatable it is returned as-is.
+    If the locale is None the object is translated to the system locale.
+
+    :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
+    """
+    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):
+        # 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.
+
+    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.
+
+    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)
+
+
+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.
     """
-    gettext.install(domain,
-                    localedir=os.environ.get(domain.upper() + '_LOCALEDIR'),
-                    unicode=True)
+
+    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
+        """
+        # 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
+
+    def setFormatter(self, fmt):
+        self.target.setFormatter(fmt)
+
+    def emit(self, record):
+        # 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)