# -*- coding: utf-8 -*-
#
# Copyright (C) 2007 Edgewall Software
# All rights reserved.
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution. The terms
# are also available at http://babel.edgewall.org/wiki/License.
#
# This software consists of voluntary contributions made by many
# individuals. For the exact contribution history, see the revision
# history and logs, available at http://babel.edgewall.org/log/.
"""Low-level locale data access.
:note: The `Locale` class, which uses this module under the hood, provides a
more convenient interface for accessing the locale data.
"""
import os
import pickle
try:
import threading
except ImportError:
import dummy_threading as threading
from UserDict import DictMixin
__all__ = ['exists', 'list', 'load']
__docformat__ = 'restructuredtext en'
_cache = {}
_cache_lock = threading.RLock()
_dirname = os.path.join(os.path.dirname(__file__), 'localedata')
def exists(name):
"""Check whether locale data is available for the given locale.
:param name: the locale identifier string
:return: `True` if the locale data exists, `False` otherwise
:rtype: `bool`
"""
if name in _cache:
return True
return os.path.exists(os.path.join(_dirname, '%s.dat' % name))
def list():
"""Return a list of all locale identifiers for which locale data is
available.
:return: a list of locale identifiers (strings)
:rtype: `list`
:since: version 0.8.1
"""
return [stem for stem, extension in [
os.path.splitext(filename) for filename in os.listdir(_dirname)
] if extension == '.dat' and stem != 'root']
def load(name, merge_inherited=True):
"""Load the locale data for the given locale.
The locale data is a dictionary that contains much of the data defined by
the Common Locale Data Repository (CLDR). This data is stored as a
collection of pickle files inside the ``babel`` package.
>>> d = load('en_US')
>>> d['languages']['sv']
u'Swedish'
Note that the results are cached, and subsequent requests for the same
locale return the same dictionary:
>>> d1 = load('en_US')
>>> d2 = load('en_US')
>>> d1 is d2
True
:param name: the locale identifier string (or "root")
:param merge_inherited: whether the inherited data should be merged into
the data of the requested locale
:return: the locale data
:rtype: `dict`
:raise `IOError`: if no locale data file is found for the given locale
identifer, or one of the locales it inherits from
"""
_cache_lock.acquire()
try:
data = _cache.get(name)
if not data:
# Load inherited data
if name == 'root' or not merge_inherited:
data = {}
else:
parts = name.split('_')
if len(parts) == 1:
parent = 'root'
else:
parent = '_'.join(parts[:-1])
data = load(parent).copy()
filename = os.path.join(_dirname, '%s.dat' % name)
fileobj = open(filename, 'rb')
try:
if name != 'root' and merge_inherited:
merge(data, pickle.load(fileobj))
else:
data = pickle.load(fileobj)
_cache[name] = data
finally:
fileobj.close()
return data
finally:
_cache_lock.release()
def merge(dict1, dict2):
"""Merge the data from `dict2` into the `dict1` dictionary, making copies
of nested dictionaries.
>>> d = {1: 'foo', 3: 'baz'}
>>> merge(d, {1: 'Foo', 2: 'Bar'})
>>> items = d.items(); items.sort(); items
[(1, 'Foo'), (2, 'Bar'), (3, 'baz')]
:param dict1: the dictionary to merge into
:param dict2: the dictionary containing the data that should be merged
"""
for key, val2 in dict2.items():
if val2 is not None:
val1 = dict1.get(key)
if isinstance(val2, dict):
if val1 is None:
val1 = {}
if isinstance(val1, Alias):
val1 = (val1, val2)
elif isinstance(val1, tuple):
alias, others = val1
others = others.copy()
merge(others, val2)
val1 = (alias, others)
else:
val1 = val1.copy()
merge(val1, val2)
else:
val1 = val2
dict1[key] = val1
class Alias(object):
"""Representation of an alias in the locale data.
An alias is a value that refers to some other part of the locale data,
as specified by the `keys`.
"""
def __init__(self, keys):
self.keys = tuple(keys)
def __repr__(self):
return '<%s %r>' % (type(self).__name__, self.keys)
def resolve(self, data):
"""Resolve the alias based on the given data.
This is done recursively, so if one alias resolves to a second alias,
that second alias will also be resolved.
:param data: the locale data
:type data: `dict`
"""
base = data
for key in self.keys:
data = data[key]
if isinstance(data, Alias):
data = data.resolve(base)
elif isinstance(data, tuple):
alias, others = data
data = alias.resolve(base)
return data
class LocaleDataDict(DictMixin, dict):
"""Dictionary wrapper that automatically resolves aliases to the actual
values.
"""
def __init__(self, data, base=None):
dict.__init__(self, data)
if base is None:
base = data
self.base = base
def __getitem__(self, key):
orig = val = dict.__getitem__(self, key)
if isinstance(val, Alias): # resolve an alias
val = val.resolve(self.base)
if isinstance(val, tuple): # Merge a partial dict with an alias
alias, others = val
val = alias.resolve(self.base).copy()
merge(val, others)
if type(val) is dict: # Return a nested alias-resolving dict
val = LocaleDataDict(val, base=self.base)
if val is not orig:
self[key] = val
return val
def copy(self):
return LocaleDataDict(dict.copy(self), base=self.base)