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# -*- coding: utf-8 -*-
"""
babel.messages.catalog
~~~~~~~~~~~~~~~~~~~~~~
Data structures for message catalogs.
:copyright: (c) 2013 by the Babel Team.
:license: BSD, see LICENSE for more details.
"""
import re
import time
from cgi import parse_header
from datetime import datetime, time as time_
from difflib import get_close_matches
from email import message_from_string
from copy import copy
from babel import __version__ as VERSION
from babel.core import Locale
from babel.dates import format_datetime
from babel.messages.plurals import get_plural
from babel.util import odict, distinct, LOCALTZ, FixedOffsetTimezone
from babel._compat import string_types, number_types, PY2, cmp
__all__ = ['Message', 'Catalog', 'TranslationError']
PYTHON_FORMAT = re.compile(r'''
\%
(?:\(([\w]*)\))?
(
[-#0\ +]?(?:\*|[\d]+)?
(?:\.(?:\*|[\d]+))?
[hlL]?
)
([diouxXeEfFgGcrs%])
''', re.VERBOSE)
def _parse_datetime_header(value):
match = re.match(r'^(?P<datetime>.*?)(?P<tzoffset>[+-]\d{4})?$', value)
tt = time.strptime(match.group('datetime'), '%Y-%m-%d %H:%M')
ts = time.mktime(tt)
dt = datetime.fromtimestamp(ts)
# Separate the offset into a sign component, hours, and # minutes
tzoffset = match.group('tzoffset')
if tzoffset is not None:
plus_minus_s, rest = tzoffset[0], tzoffset[1:]
hours_offset_s, mins_offset_s = rest[:2], rest[2:]
# Make them all integers
plus_minus = int(plus_minus_s + '1')
hours_offset = int(hours_offset_s)
mins_offset = int(mins_offset_s)
# Calculate net offset
net_mins_offset = hours_offset * 60
net_mins_offset += mins_offset
net_mins_offset *= plus_minus
# Create an offset object
tzoffset = FixedOffsetTimezone(net_mins_offset)
# Store the offset in a datetime object
dt = dt.replace(tzinfo=tzoffset)
return dt
class Message(object):
"""Representation of a single message in a catalog."""
def __init__(self, id, string=u'', locations=(), flags=(), auto_comments=(),
user_comments=(), previous_id=(), lineno=None, context=None):
"""Create the message object.
:param id: the message ID, or a ``(singular, plural)`` tuple for
pluralizable messages
:param string: the translated message string, or a
``(singular, plural)`` tuple for pluralizable messages
:param locations: a sequence of ``(filename, lineno)`` tuples
:param flags: a set or sequence of flags
:param auto_comments: a sequence of automatic comments for the message
:param user_comments: a sequence of user comments for the message
:param previous_id: the previous message ID, or a ``(singular, plural)``
tuple for pluralizable messages
:param lineno: the line number on which the msgid line was found in the
PO file, if any
:param context: the message context
"""
self.id = id
if not string and self.pluralizable:
string = (u'', u'')
self.string = string
self.locations = list(distinct(locations))
self.flags = set(flags)
if id and self.python_format:
self.flags.add('python-format')
else:
self.flags.discard('python-format')
self.auto_comments = list(distinct(auto_comments))
self.user_comments = list(distinct(user_comments))
if isinstance(previous_id, string_types):
self.previous_id = [previous_id]
else:
self.previous_id = list(previous_id)
self.lineno = lineno
self.context = context
def __repr__(self):
return '<%s %r (flags: %r)>' % (type(self).__name__, self.id,
list(self.flags))
def __cmp__(self, other):
"""Compare Messages, taking into account plural ids"""
def values_to_compare(obj):
if isinstance(obj, Message) and obj.pluralizable:
return (obj.id[0], obj.context or '')
return (obj.id, obj.context or '')
return cmp(values_to_compare(self), values_to_compare(other))
def __gt__(self, other):
return self.__cmp__(other) > 0
def __lt__(self, other):
return self.__cmp__(other) < 0
def __ge__(self, other):
return self.__cmp__(other) >= 0
def __le__(self, other):
return self.__cmp__(other) <= 0
def __eq__(self, other):
return self.__cmp__(other) == 0
def __ne__(self, other):
return self.__cmp__(other) != 0
def clone(self):
return Message(*map(copy, (self.id, self.string, self.locations,
self.flags, self.auto_comments,
self.user_comments, self.previous_id,
self.lineno, self.context)))
def check(self, catalog=None):
"""Run various validation checks on the message. Some validations
are only performed if the catalog is provided. This method returns
a sequence of `TranslationError` objects.
:rtype: ``iterator``
:param catalog: A catalog instance that is passed to the checkers
:see: `Catalog.check` for a way to perform checks for all messages
in a catalog.
"""
from babel.messages.checkers import checkers
errors = []
for checker in checkers:
try:
checker(catalog, self)
except TranslationError as e:
errors.append(e)
return errors
@property
def fuzzy(self):
"""Whether the translation is fuzzy.
>>> Message('foo').fuzzy
False
>>> msg = Message('foo', 'foo', flags=['fuzzy'])
>>> msg.fuzzy
True
>>> msg
<Message 'foo' (flags: ['fuzzy'])>
:type: `bool`"""
return 'fuzzy' in self.flags
@property
def pluralizable(self):
"""Whether the message is plurizable.
>>> Message('foo').pluralizable
False
>>> Message(('foo', 'bar')).pluralizable
True
:type: `bool`"""
return isinstance(self.id, (list, tuple))
@property
def python_format(self):
"""Whether the message contains Python-style parameters.
>>> Message('foo %(name)s bar').python_format
True
>>> Message(('foo %(name)s', 'foo %(name)s')).python_format
True
:type: `bool`"""
ids = self.id
if not isinstance(ids, (list, tuple)):
ids = [ids]
return any(PYTHON_FORMAT.search(id) for id in ids)
class TranslationError(Exception):
"""Exception thrown by translation checkers when invalid message
translations are encountered."""
DEFAULT_HEADER = u"""\
# Translations template for PROJECT.
# Copyright (C) YEAR ORGANIZATION
# This file is distributed under the same license as the PROJECT project.
# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
#"""
if PY2:
def _parse_header(header_string):
# message_from_string only works for str, not for unicode
headers = message_from_string(header_string.encode('utf8'))
decoded_headers = {}
for name, value in headers.items():
name = name.decode('utf8')
value = value.decode('utf8')
decoded_headers[name] = value
return decoded_headers
else:
_parse_header = message_from_string
class Catalog(object):
"""Representation of a message catalog."""
def __init__(self, locale=None, domain=None, header_comment=DEFAULT_HEADER,
project=None, version=None, copyright_holder=None,
msgid_bugs_address=None, creation_date=None,
revision_date=None, last_translator=None, language_team=None,
charset=None, fuzzy=True):
"""Initialize the catalog object.
:param locale: the locale identifier or `Locale` object, or `None`
if the catalog is not bound to a locale (which basically
means it's a template)
:param domain: the message domain
:param header_comment: the header comment as string, or `None` for the
default header
:param project: the project's name
:param version: the project's version
:param copyright_holder: the copyright holder of the catalog
:param msgid_bugs_address: the email address or URL to submit bug
reports to
:param creation_date: the date the catalog was created
:param revision_date: the date the catalog was revised
:param last_translator: the name and email of the last translator
:param language_team: the name and email of the language team
:param charset: the encoding to use in the output (defaults to utf-8)
:param fuzzy: the fuzzy bit on the catalog header
"""
self.domain = domain
if locale:
locale = Locale.parse(locale)
self.locale = locale
self._header_comment = header_comment
self._messages = odict()
self.project = project or 'PROJECT'
self.version = version or 'VERSION'
self.copyright_holder = copyright_holder or 'ORGANIZATION'
self.msgid_bugs_address = msgid_bugs_address or 'EMAIL@ADDRESS'
self.last_translator = last_translator or 'FULL NAME <EMAIL@ADDRESS>'
"""Name and email address of the last translator."""
self.language_team = language_team or 'LANGUAGE <LL@li.org>'
"""Name and email address of the language team."""
self.charset = charset or 'utf-8'
if creation_date is None:
creation_date = datetime.now(LOCALTZ)
elif isinstance(creation_date, datetime) and not creation_date.tzinfo:
creation_date = creation_date.replace(tzinfo=LOCALTZ)
self.creation_date = creation_date
if revision_date is None:
revision_date = 'YEAR-MO-DA HO:MI+ZONE'
elif isinstance(revision_date, datetime) and not revision_date.tzinfo:
revision_date = revision_date.replace(tzinfo=LOCALTZ)
self.revision_date = revision_date
self.fuzzy = fuzzy
self.obsolete = odict() # Dictionary of obsolete messages
self._num_plurals = None
self._plural_expr = None
def _get_header_comment(self):
comment = self._header_comment
year = datetime.now(LOCALTZ).strftime('%Y')
if hasattr(self.revision_date, 'strftime'):
year = self.revision_date.strftime('%Y')
comment = comment.replace('PROJECT', self.project) \
.replace('VERSION', self.version) \
.replace('YEAR', year) \
.replace('ORGANIZATION', self.copyright_holder)
if self.locale:
comment = comment.replace('Translations template', '%s translations'
% self.locale.english_name)
return comment
def _set_header_comment(self, string):
self._header_comment = string
header_comment = property(_get_header_comment, _set_header_comment, doc="""\
The header comment for the catalog.
>>> catalog = Catalog(project='Foobar', version='1.0',
... copyright_holder='Foo Company')
>>> print(catalog.header_comment) #doctest: +ELLIPSIS
# Translations template for Foobar.
# Copyright (C) ... Foo Company
# This file is distributed under the same license as the Foobar project.
# FIRST AUTHOR <EMAIL@ADDRESS>, ....
#
The header can also be set from a string. Any known upper-case variables
will be replaced when the header is retrieved again:
>>> catalog = Catalog(project='Foobar', version='1.0',
... copyright_holder='Foo Company')
>>> catalog.header_comment = '''\\
... # The POT for my really cool PROJECT project.
... # Copyright (C) 1990-2003 ORGANIZATION
... # This file is distributed under the same license as the PROJECT
... # project.
... #'''
>>> print(catalog.header_comment)
# The POT for my really cool Foobar project.
# Copyright (C) 1990-2003 Foo Company
# This file is distributed under the same license as the Foobar
# project.
#
:type: `unicode`
""")
def _get_mime_headers(self):
headers = []
headers.append(('Project-Id-Version',
'%s %s' % (self.project, self.version)))
headers.append(('Report-Msgid-Bugs-To', self.msgid_bugs_address))
headers.append(('POT-Creation-Date',
format_datetime(self.creation_date, 'yyyy-MM-dd HH:mmZ',
locale='en')))
if isinstance(self.revision_date, (datetime, time_) + number_types):
headers.append(('PO-Revision-Date',
format_datetime(self.revision_date,
'yyyy-MM-dd HH:mmZ', locale='en')))
else:
headers.append(('PO-Revision-Date', self.revision_date))
headers.append(('Last-Translator', self.last_translator))
if self.locale is not None:
headers.append(('Language', str(self.locale)))
if (self.locale is not None) and ('LANGUAGE' in self.language_team):
headers.append(('Language-Team',
self.language_team.replace('LANGUAGE',
str(self.locale))))
else:
headers.append(('Language-Team', self.language_team))
if self.locale is not None:
headers.append(('Plural-Forms', self.plural_forms))
headers.append(('MIME-Version', '1.0'))
headers.append(('Content-Type',
'text/plain; charset=%s' % self.charset))
headers.append(('Content-Transfer-Encoding', '8bit'))
headers.append(('Generated-By', 'Babel %s\n' % VERSION))
return headers
def _set_mime_headers(self, headers):
for name, value in headers:
name = name.lower()
if name == 'project-id-version':
parts = value.split(' ')
self.project = u' '.join(parts[:-1])
self.version = parts[-1]
elif name == 'report-msgid-bugs-to':
self.msgid_bugs_address = value
elif name == 'last-translator':
self.last_translator = value
elif name == 'language':
value = value.replace('-', '_')
self.locale = Locale.parse(value)
elif name == 'language-team':
self.language_team = value
elif name == 'content-type':
mimetype, params = parse_header(value)
if 'charset' in params:
self.charset = params['charset'].lower()
elif name == 'plural-forms':
_, params = parse_header(' ;' + value)
self._num_plurals = int(params.get('nplurals', 2))
self._plural_expr = params.get('plural', '(n != 1)')
elif name == 'pot-creation-date':
self.creation_date = _parse_datetime_header(value)
elif name == 'po-revision-date':
# Keep the value if it's not the default one
if 'YEAR' not in value:
self.revision_date = _parse_datetime_header(value)
mime_headers = property(_get_mime_headers, _set_mime_headers, doc="""\
The MIME headers of the catalog, used for the special ``msgid ""`` entry.
The behavior of this property changes slightly depending on whether a locale
is set or not, the latter indicating that the catalog is actually a template
for actual translations.
Here's an example of the output for such a catalog template:
>>> from babel.dates import UTC
>>> created = datetime(1990, 4, 1, 15, 30, tzinfo=UTC)
>>> catalog = Catalog(project='Foobar', version='1.0',
... creation_date=created)
>>> for name, value in catalog.mime_headers:
... print('%s: %s' % (name, value))
Project-Id-Version: Foobar 1.0
Report-Msgid-Bugs-To: EMAIL@ADDRESS
POT-Creation-Date: 1990-04-01 15:30+0000
PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE
Last-Translator: FULL NAME <EMAIL@ADDRESS>
Language-Team: LANGUAGE <LL@li.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
Generated-By: Babel ...
And here's an example of the output when the locale is set:
>>> revised = datetime(1990, 8, 3, 12, 0, tzinfo=UTC)
>>> catalog = Catalog(locale='de_DE', project='Foobar', version='1.0',
... creation_date=created, revision_date=revised,
... last_translator='John Doe <jd@example.com>',
... language_team='de_DE <de@example.com>')
>>> for name, value in catalog.mime_headers:
... print('%s: %s' % (name, value))
Project-Id-Version: Foobar 1.0
Report-Msgid-Bugs-To: EMAIL@ADDRESS
POT-Creation-Date: 1990-04-01 15:30+0000
PO-Revision-Date: 1990-08-03 12:00+0000
Last-Translator: John Doe <jd@example.com>
Language: de_DE
Language-Team: de_DE <de@example.com>
Plural-Forms: nplurals=2; plural=(n != 1)
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
Generated-By: Babel ...
:type: `list`
""")
@property
def num_plurals(self):
"""The number of plurals used by the catalog or locale.
>>> Catalog(locale='en').num_plurals
2
>>> Catalog(locale='ga').num_plurals
5
:type: `int`"""
if self._num_plurals is None:
num = 2
if self.locale:
num = get_plural(self.locale)[0]
self._num_plurals = num
return self._num_plurals
@property
def plural_expr(self):
"""The plural expression used by the catalog or locale.
>>> Catalog(locale='en').plural_expr
'(n != 1)'
>>> Catalog(locale='ga').plural_expr
'(n==1 ? 0 : n==2 ? 1 : n>=3 && n<=6 ? 2 : n>=7 && n<=10 ? 3 : 4)'
:type: `string_types`"""
if self._plural_expr is None:
expr = '(n != 1)'
if self.locale:
expr = get_plural(self.locale)[1]
self._plural_expr = expr
return self._plural_expr
@property
def plural_forms(self):
"""Return the plural forms declaration for the locale.
>>> Catalog(locale='en').plural_forms
'nplurals=2; plural=(n != 1)'
>>> Catalog(locale='pt_BR').plural_forms
'nplurals=2; plural=(n > 1)'
:type: `str`"""
return 'nplurals=%s; plural=%s' % (self.num_plurals, self.plural_expr)
def __contains__(self, id):
"""Return whether the catalog has a message with the specified ID."""
return self._key_for(id) in self._messages
def __len__(self):
"""The number of messages in the catalog.
This does not include the special ``msgid ""`` entry."""
return len(self._messages)
def __iter__(self):
"""Iterates through all the entries in the catalog, in the order they
were added, yielding a `Message` object for every entry.
:rtype: ``iterator``"""
buf = []
for name, value in self.mime_headers:
buf.append('%s: %s' % (name, value))
flags = set()
if self.fuzzy:
flags |= set(['fuzzy'])
yield Message(u'', '\n'.join(buf), flags=flags)
for key in self._messages:
yield self._messages[key]
def __repr__(self):
locale = ''
if self.locale:
locale = ' %s' % self.locale
return '<%s %r%s>' % (type(self).__name__, self.domain, locale)
def __delitem__(self, id):
"""Delete the message with the specified ID."""
self.delete(id)
def __getitem__(self, id):
"""Return the message with the specified ID.
:param id: the message ID
"""
return self.get(id)
def __setitem__(self, id, message):
"""Add or update the message with the specified ID.
>>> catalog = Catalog()
>>> catalog[u'foo'] = Message(u'foo')
>>> catalog[u'foo']
<Message u'foo' (flags: [])>
If a message with that ID is already in the catalog, it is updated
to include the locations and flags of the new message.
>>> catalog = Catalog()
>>> catalog[u'foo'] = Message(u'foo', locations=[('main.py', 1)])
>>> catalog[u'foo'].locations
[('main.py', 1)]
>>> catalog[u'foo'] = Message(u'foo', locations=[('utils.py', 5)])
>>> catalog[u'foo'].locations
[('main.py', 1), ('utils.py', 5)]
:param id: the message ID
:param message: the `Message` object
"""
assert isinstance(message, Message), 'expected a Message object'
key = self._key_for(id, message.context)
current = self._messages.get(key)
if current:
if message.pluralizable and not current.pluralizable:
# The new message adds pluralization
current.id = message.id
current.string = message.string
current.locations = list(distinct(current.locations +
message.locations))
current.auto_comments = list(distinct(current.auto_comments +
message.auto_comments))
current.user_comments = list(distinct(current.user_comments +
message.user_comments))
current.flags |= message.flags
message = current
elif id == '':
# special treatment for the header message
self.mime_headers = _parse_header(message.string).items()
self.header_comment = '\n'.join([('# %s' % c).rstrip() for c
in message.user_comments])
self.fuzzy = message.fuzzy
else:
if isinstance(id, (list, tuple)):
assert isinstance(message.string, (list, tuple)), \
'Expected sequence but got %s' % type(message.string)
self._messages[key] = message
def add(self, id, string=None, locations=(), flags=(), auto_comments=(),
user_comments=(), previous_id=(), lineno=None, context=None):
"""Add or update the message with the specified ID.
>>> catalog = Catalog()
>>> catalog.add(u'foo')
<Message ...>
>>> catalog[u'foo']
<Message u'foo' (flags: [])>
This method simply constructs a `Message` object with the given
arguments and invokes `__setitem__` with that object.
:param id: the message ID, or a ``(singular, plural)`` tuple for
pluralizable messages
:param string: the translated message string, or a
``(singular, plural)`` tuple for pluralizable messages
:param locations: a sequence of ``(filename, lineno)`` tuples
:param flags: a set or sequence of flags
:param auto_comments: a sequence of automatic comments
:param user_comments: a sequence of user comments
:param previous_id: the previous message ID, or a ``(singular, plural)``
tuple for pluralizable messages
:param lineno: the line number on which the msgid line was found in the
PO file, if any
:param context: the message context
"""
message = Message(id, string, list(locations), flags, auto_comments,
user_comments, previous_id, lineno=lineno,
context=context)
self[id] = message
return message
def check(self):
"""Run various validation checks on the translations in the catalog.
For every message which fails validation, this method yield a
``(message, errors)`` tuple, where ``message`` is the `Message` object
and ``errors`` is a sequence of `TranslationError` objects.
:rtype: ``iterator``
"""
for message in self._messages.values():
errors = message.check(catalog=self)
if errors:
yield message, errors
def get(self, id, context=None):
"""Return the message with the specified ID and context.
:param id: the message ID
:param context: the message context, or ``None`` for no context
"""
return self._messages.get(self._key_for(id, context))
def delete(self, id, context=None):
"""Delete the message with the specified ID and context.
:param id: the message ID
:param context: the message context, or ``None`` for no context
"""
key = self._key_for(id, context)
if key in self._messages:
del self._messages[key]
def update(self, template, no_fuzzy_matching=False, update_header_comment=False):
"""Update the catalog based on the given template catalog.
>>> from babel.messages import Catalog
>>> template = Catalog()
>>> template.add('green', locations=[('main.py', 99)])
<Message ...>
>>> template.add('blue', locations=[('main.py', 100)])
<Message ...>
>>> template.add(('salad', 'salads'), locations=[('util.py', 42)])
<Message ...>
>>> catalog = Catalog(locale='de_DE')
>>> catalog.add('blue', u'blau', locations=[('main.py', 98)])
<Message ...>
>>> catalog.add('head', u'Kopf', locations=[('util.py', 33)])
<Message ...>
>>> catalog.add(('salad', 'salads'), (u'Salat', u'Salate'),
... locations=[('util.py', 38)])
<Message ...>
>>> catalog.update(template)
>>> len(catalog)
3
>>> msg1 = catalog['green']
>>> msg1.string
>>> msg1.locations
[('main.py', 99)]
>>> msg2 = catalog['blue']
>>> msg2.string
u'blau'
>>> msg2.locations
[('main.py', 100)]
>>> msg3 = catalog['salad']
>>> msg3.string
(u'Salat', u'Salate')
>>> msg3.locations
[('util.py', 42)]
Messages that are in the catalog but not in the template are removed
from the main collection, but can still be accessed via the `obsolete`
member:
>>> 'head' in catalog
False
>>> list(catalog.obsolete.values())
[<Message 'head' (flags: [])>]
:param template: the reference catalog, usually read from a POT file
:param no_fuzzy_matching: whether to use fuzzy matching of message IDs
"""
messages = self._messages
remaining = messages.copy()
self._messages = odict()
# Prepare for fuzzy matching
fuzzy_candidates = []
if not no_fuzzy_matching:
fuzzy_candidates = dict([
(self._key_for(msgid), messages[msgid].context)
for msgid in messages if msgid and messages[msgid].string
])
fuzzy_matches = set()
def _merge(message, oldkey, newkey):
message = message.clone()
fuzzy = False
if oldkey != newkey:
fuzzy = True
fuzzy_matches.add(oldkey)
oldmsg = messages.get(oldkey)
if isinstance(oldmsg.id, string_types):
message.previous_id = [oldmsg.id]
else:
message.previous_id = list(oldmsg.id)
else:
oldmsg = remaining.pop(oldkey, None)
message.string = oldmsg.string
if isinstance(message.id, (list, tuple)):
if not isinstance(message.string, (list, tuple)):
fuzzy = True
message.string = tuple(
[message.string] + ([u''] * (len(message.id) - 1))
)
elif len(message.string) != self.num_plurals:
fuzzy = True
message.string = tuple(message.string[:len(oldmsg.string)])
elif isinstance(message.string, (list, tuple)):
fuzzy = True
message.string = message.string[0]
message.flags |= oldmsg.flags
if fuzzy:
message.flags |= set([u'fuzzy'])
self[message.id] = message
for message in template:
if message.id:
key = self._key_for(message.id, message.context)
if key in messages:
_merge(message, key, key)
else:
if no_fuzzy_matching is False:
# do some fuzzy matching with difflib
if isinstance(key, tuple):
matchkey = key[0] # just the msgid, no context
else:
matchkey = key
matches = get_close_matches(matchkey.lower().strip(),
fuzzy_candidates.keys(), 1)
if matches:
newkey = matches[0]
newctxt = fuzzy_candidates[newkey]
if newctxt is not None:
newkey = newkey, newctxt
_merge(message, newkey, key)
continue
self[message.id] = message
for msgid in remaining:
if no_fuzzy_matching or msgid not in fuzzy_matches:
self.obsolete[msgid] = remaining[msgid]
if update_header_comment:
# Allow the updated catalog's header to be rewritten based on the
# template's header
self.header_comment = template.header_comment
# Make updated catalog's POT-Creation-Date equal to the template
# used to update the catalog
self.creation_date = template.creation_date
def _key_for(self, id, context=None):
"""The key for a message is just the singular ID even for pluralizable
messages, but is a ``(msgid, msgctxt)`` tuple for context-specific
messages.
"""
key = id
if isinstance(key, (list, tuple)):
key = id[0]
if context is not None:
key = (key, context)
return key