# -*- coding: utf-8 -*-
# SPDX-License-Identifier: AGPL-3.0-or-later
# lint: pylint
"""Initialize :py:obj:`LOCALE_NAMES`, :py:obj:`RTL_LOCALES`.
"""
from typing import Set
import os
import pathlib
from babel import Locale
from babel.support import Translations
import babel.languages
import babel.core
import flask_babel
import flask
from flask.ctx import has_request_context
from searx import logger
logger = logger.getChild('locales')
# safe before monkey patching flask_babel.get_translations
_flask_babel_get_translations = flask_babel.get_translations
LOCALE_NAMES = {}
"""Mapping of locales and their description. Locales e.g. 'fr' or 'pt-BR' (see
:py:obj:`locales_initialize`).
:meta hide-value:
"""
RTL_LOCALES: Set[str] = set()
"""List of *Right-To-Left* locales e.g. 'he' or 'fa-IR' (see
:py:obj:`locales_initialize`)."""
ADDITIONAL_TRANSLATIONS = {
"oc": "Occitan",
"szl": "Ślōnski (Silesian)",
"pap": "Papiamento",
}
"""Additional languages SearXNG has translations for but not supported by
python-babel (see :py:obj:`locales_initialize`)."""
LOCALE_BEST_MATCH = {
"oc": 'fr-FR',
"szl": "pl",
"nl-BE": "nl",
"zh-HK": "zh-Hant-TW",
"pap": "pt-BR",
}
"""Map a locale we do not have a translations for to a locale we have a
translation for. By example: use Taiwan version of the translation for Hong
Kong."""
def localeselector():
locale = 'en'
if has_request_context():
value = flask.request.preferences.get_value('locale')
if value:
locale = value
# first, set the language that is not supported by babel
if locale in ADDITIONAL_TRANSLATIONS:
flask.request.form['use-translation'] = locale
# second, map locale to a value python-babel supports
locale = LOCALE_BEST_MATCH.get(locale, locale)
if locale == '':
# if there is an error loading the preferences
# the locale is going to be ''
locale = 'en'
# babel uses underscore instead of hyphen.
locale = locale.replace('-', '_')
return locale
def get_translations():
"""Monkey patch of :py:obj:`flask_babel.get_translations`"""
if has_request_context() and flask.request.form.get('use-translation') == 'oc':
babel_ext = flask_babel.current_app.extensions['babel']
return Translations.load(next(babel_ext.translation_directories), 'oc')
if has_request_context() and flask.request.form.get('use-translation') == 'szl':
babel_ext = flask_babel.current_app.extensions['babel']
return Translations.load(next(babel_ext.translation_directories), 'szl')
if has_request_context() and flask.request.form.get('use-translation') == 'pap':
babel_ext = flask_babel.current_app.extensions['babel']
return Translations.load(next(babel_ext.translation_directories), 'pap')
return _flask_babel_get_translations()
def get_locale_descr(locale, locale_name):
"""Get locale name e.g. 'Français - fr' or 'Português (Brasil) - pt-BR'
:param locale: instance of :py:class:`Locale`
:param locale_name: name e.g. 'fr' or 'pt_BR' (delimiter is *underscore*)
"""
native_language, native_territory = _get_locale_descr(locale, locale_name)
english_language, english_territory = _get_locale_descr(locale, 'en')
if native_territory == english_territory:
english_territory = None
if not native_territory and not english_territory:
if native_language == english_language:
return native_language
return native_language + ' (' + english_language + ')'
result = native_language + ', ' + native_territory + ' (' + english_language
if english_territory:
return result + ', ' + english_territory + ')'
return result + ')'
def _get_locale_descr(locale, language_code):
language_name = locale.get_language_name(language_code).capitalize()
if language_name and ('a' <= language_name[0] <= 'z'):
language_name = language_name.capitalize()
terrirtory_name = locale.get_territory_name(language_code)
return language_name, terrirtory_name
def locales_initialize(directory=None):
"""Initialize locales environment of the SearXNG session.
- monkey patch :py:obj:`flask_babel.get_translations` by :py:obj:`get_translations`
- init global names :py:obj:`LOCALE_NAMES`, :py:obj:`RTL_LOCALES`
"""
directory = directory or pathlib.Path(__file__).parent / 'translations'
logger.debug("locales_initialize: %s", directory)
flask_babel.get_translations = get_translations
for tag, descr in ADDITIONAL_TRANSLATIONS.items():
LOCALE_NAMES[tag] = descr
for tag in LOCALE_BEST_MATCH:
descr = LOCALE_NAMES.get(tag)
if not descr:
locale = Locale.parse(tag, sep='-')
LOCALE_NAMES[tag] = get_locale_descr(locale, tag.replace('-', '_'))
for dirname in sorted(os.listdir(directory)):
# Based on https://flask-babel.tkte.ch/_modules/flask_babel.html#Babel.list_translations
if not os.path.isdir(os.path.join(directory, dirname, 'LC_MESSAGES')):
continue
tag = dirname.replace('_', '-')
descr = LOCALE_NAMES.get(tag)
if not descr:
locale = Locale.parse(dirname)
LOCALE_NAMES[tag] = get_locale_descr(locale, dirname)
if locale.text_direction == 'rtl':
RTL_LOCALES.add(tag)
def get_engine_locale(searxng_locale, engine_locales, default=None):
"""Return engine's language (aka locale) string that best fits to argument
``searxng_locale``.
Argument ``engine_locales`` is a python dict that maps *SearXNG locales* to
corresponding *engine locales*::
<engine>: {
# SearXNG string : engine-string
'ca-ES' : 'ca_ES',
'fr-BE' : 'fr_BE',
'fr-CA' : 'fr_CA',
'fr-CH' : 'fr_CH',
'fr' : 'fr_FR',
...
'pl-PL' : 'pl_PL',
'pt-PT' : 'pt_PT'
}
.. hint::
The *SearXNG locale* string has to be known by babel!
If there is no direct 1:1 mapping, this functions tries to narrow down
engine's language (locale). If no value can be determined by these
approximation attempts the ``default`` value is returned.
Assumptions:
A. When user select a language the results should be optimized according to
the selected language.
B. When user select a language and a territory the results should be
optimized with first priority on terrirtory and second on language.
First approximation rule (*by territory*):
When the user selects a locale with terrirtory (and a language), the
territory has priority over the language. If any of the offical languages
in the terrirtory is supported by the engine (``engine_locales``) it will
be used.
Second approximation rule (*by language*):
If "First approximation rule" brings no result or the user selects only a
language without a terrirtory. Check in which territories the language
has an offical status and if one of these territories is supported by the
engine.
"""
# pylint: disable=too-many-branches
engine_locale = engine_locales.get(searxng_locale)
if engine_locale is not None:
# There was a 1:1 mapping (e.g. "fr-BE --> fr_BE" or "fr --> fr_FR"), no
# need to narrow language nor territory.
return engine_locale
try:
locale = babel.Locale.parse(searxng_locale, sep='-')
except babel.core.UnknownLocaleError:
try:
locale = babel.Locale.parse(searxng_locale.split('-')[0])
except babel.core.UnknownLocaleError:
return default
# SearXNG's selected locale is not supported by the engine ..
if locale.territory:
# Try to narrow by *offical* languages in the territory (??-XX).
for official_language in babel.languages.get_official_languages(locale.territory, de_facto=True):
searxng_locale = official_language + '-' + locale.territory
engine_locale = engine_locales.get(searxng_locale)
if engine_locale is not None:
return engine_locale
# Engine does not support one of the offical languages in the territory or
# there is only a language selected without a territory.
# Now lets have a look if the searxng_lang (the language selected by the
# user) is a offical language in other territories. If so, check if
# engine does support the searxng_lang in this other territory.
if locale.language:
searxng_lang = locale.language
if locale.script:
searxng_lang += '_' + locale.script
terr_lang_dict = {}
for territory, langs in babel.core.get_global("territory_languages").items():
if not langs.get(searxng_lang, {}).get('official_status'):
continue
terr_lang_dict[territory] = langs.get(searxng_lang)
# first: check fr-FR, de-DE .. is supported by the engine
# exception: 'en' --> 'en-US'
territory = locale.language.upper()
if territory == 'EN':
territory = 'US'
if terr_lang_dict.get(territory):
searxng_locale = locale.language + '-' + territory
engine_locale = engine_locales.get(searxng_locale)
if engine_locale is not None:
return engine_locale
# second: sort by population_percent and take first match
# drawback of "population percent": if there is a terrirtory with a
# small number of people (e.g 100) but the majority speaks the
# language, then the percentage migth be 100% (--> 100 people) but in
# a different terrirtory with more people (e.g. 10.000) where only 10%
# speak the language the total amount of speaker is higher (--> 200
# people).
#
# By example: The population of Saint-Martin is 33.000, of which 100%
# speak French, but this is less than the 30% of the approximately 2.5
# million Belgian citizens
#
# - 'fr-MF', 'population_percent': 100.0, 'official_status': 'official'
# - 'fr-BE', 'population_percent': 38.0, 'official_status': 'official'
terr_lang_list = []
for k, v in terr_lang_dict.items():
terr_lang_list.append((k, v))
for territory, _lang in sorted(terr_lang_list, key=lambda item: item[1]['population_percent'], reverse=True):
searxng_locale = locale.language + '-' + territory
engine_locale = engine_locales.get(searxng_locale)
if engine_locale is not None:
return engine_locale
# No luck: narrow by "language from territory" and "territory from language"
# does not fit to a locale supported by the engine.
if engine_locale is None:
engine_locale = default
return default