Source code for searx.locales

# -*- 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, Optional, List
import os
import pathlib

import babel
from 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

"""Mapping of locales and their description.  Locales e.g. 'fr' or 'pt-BR' (see

:meta hide-value:

RTL_LOCALES: Set[str] = set()
"""List of *Right-To-Left* locales e.g. 'he' or 'fa-IR' (see

    "dv": "ދިވެހި (Dhivehi)",
    "oc": "Occitan",
    "szl": "Ślōnski (Silesian)",
    "pap": "Papiamento",
"""Additional languages SearXNG has translations for but not supported by
python-babel (see :py:obj:`locales_initialize`)."""

    "dv": "si",
    "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

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
        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

[docs] def get_translations(): """Monkey patch of :py:obj:`flask_babel.get_translations`""" if has_request_context(): use_translation = flask.request.form.get('use-translation') if use_translation in ADDITIONAL_TRANSLATIONS: babel_ext = flask_babel.current_app.extensions['babel'] return Translations.load(babel_ext.translation_directories[0], use_translation) return _flask_babel_get_translations()
[docs] 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() territory_name = locale.get_territory_name(language_code) return language_name, territory_name
[docs] 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 = babel.Locale.parse(LOCALE_BEST_MATCH[tag], sep='-') LOCALE_NAMES[tag] = descr if locale.text_direction == 'rtl': RTL_LOCALES.add(tag) for tag in LOCALE_BEST_MATCH: descr = LOCALE_NAMES.get(tag) if not descr: locale = babel.Locale.parse(tag, sep='-') LOCALE_NAMES[tag] = get_locale_descr(locale, tag.replace('-', '_')) if locale.text_direction == 'rtl': RTL_LOCALES.add(tag) for dirname in sorted(os.listdir(directory)): # Based on 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 = babel.Locale.parse(dirname) LOCALE_NAMES[tag] = get_locale_descr(locale, dirname) if locale.text_direction == 'rtl': RTL_LOCALES.add(tag)
[docs] def region_tag(locale: babel.Locale) -> str: """Returns SearXNG's region tag from the locale (e.g. zh-TW , en-US).""" if not locale.territory: raise ValueError('%s missed a territory') return locale.language + '-' + locale.territory
[docs] def language_tag(locale: babel.Locale) -> str: """Returns SearXNG's language tag from the locale and if exits, the tag includes the script name (e.g. en, zh_Hant). """ sxng_lang = locale.language if locale.script: sxng_lang += '_' + locale.script return sxng_lang
[docs] def get_locale(locale_tag: str) -> Optional[babel.Locale]: """Returns a :py:obj:`babel.Locale` object parsed from argument ``locale_tag``""" try: locale = babel.Locale.parse(locale_tag, sep='-') return locale except babel.core.UnknownLocaleError: return None
[docs] def get_official_locales( territory: str, languages=None, regional: bool = False, de_facto: bool = True ) -> Set[babel.Locale]: """Returns a list of :py:obj:`babel.Locale` with languages from :py:obj:`babel.languages.get_official_languages`. :param territory: The territory (country or region) code. :param languages: A list of language codes the languages from :py:obj:`babel.languages.get_official_languages` should be in (intersection). If this argument is ``None``, all official languages in this territory are used. :param regional: If the regional flag is set, then languages which are regionally official are also returned. :param de_facto: If the de_facto flag is set to `False`, then languages which are “de facto” official are not returned. """ ret_val = set() o_languages = babel.languages.get_official_languages(territory, regional=regional, de_facto=de_facto) if languages: languages = [l.lower() for l in languages] o_languages = set(l for l in o_languages if l.lower() in languages) for lang in o_languages: try: locale = babel.Locale.parse(lang + '_' + territory) ret_val.add(locale) except babel.UnknownLocaleError: continue return ret_val
[docs] 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' .. 'zh' : 'zh' 'zh_Hans' : 'zh' 'zh_Hant' : 'zh_TW' } .. 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 territory and second on language. First approximation rule (*by territory*): When the user selects a locale with territory (and a language), the territory has priority over the language. If any of the official languages in the territory 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 territory. Check in which territories the language has an official status and if one of these territories is supported by the engine. """ # pylint: disable=too-many-branches, too-many-return-statements engine_locale = engine_locales.get(searxng_locale) if engine_locale is not None: # There was a 1:1 mapping (e.g. a region "fr-BE --> fr_BE" or a language # "zh --> zh"), no need to narrow language-script 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_lang = language_tag(locale) engine_locale = engine_locales.get(searxng_lang) if engine_locale is not None: # There was a 1:1 mapping (e.g. "zh-HK --> zh_Hant" or "zh-CN --> zh_Hans") return engine_locale # SearXNG's selected locale is not supported by the engine .. if locale.territory: # Try to narrow by *official* 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 official 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 official language in other territories. If so, check if # engine does support the searxng_lang in this other territory. if locale.language: 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 territory with a # small number of people (e.g 100) but the majority speaks the # language, then the percentage might be 100% (--> 100 people) but in # a different territory 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
[docs] def match_locale(searxng_locale: str, locale_tag_list: List[str], fallback: Optional[str] = None) -> Optional[str]: """Return tag from ``locale_tag_list`` that best fits to ``searxng_locale``. :param str searxng_locale: SearXNG's internal representation of locale (de, de-DE, fr-BE, zh, zh-CN, zh-TW ..). :param list locale_tag_list: The list of locale tags to select from :param str fallback: fallback locale tag (if unset --> ``None``) The rules to find a match are implemented in :py:obj:`get_engine_locale`, the ``engine_locales`` is build up by :py:obj:`build_engine_locales`. .. hint:: The *SearXNG locale* string and the members of ``locale_tag_list`` has to be known by babel! The :py:obj:`ADDITIONAL_TRANSLATIONS` are used in the UI and are not known by babel --> will be ignored. """ # searxng_locale = 'es' # locale_tag_list = ['es-AR', 'es-ES', 'es-MX'] if not searxng_locale: return fallback locale = get_locale(searxng_locale) if locale is None: return fallback # normalize to a SearXNG locale that can be passed to get_engine_locale searxng_locale = language_tag(locale) if locale.territory: searxng_locale = region_tag(locale) # clean up locale_tag_list tag_list = [] for tag in locale_tag_list: if tag in ('all', 'auto') or tag in ADDITIONAL_TRANSLATIONS: continue tag_list.append(tag) # emulate fetch_traits engine_locales = build_engine_locales(tag_list) return get_engine_locale(searxng_locale, engine_locales, default=fallback)
[docs] def build_engine_locales(tag_list: List[str]): """From a list of locale tags a dictionary is build that can be passed by argument ``engine_locales`` to :py:obj:`get_engine_locale`. This function is mainly used by :py:obj:`match_locale` and is similar to what the ``fetch_traits(..)`` function of engines do. If there are territory codes in the ``tag_list`` that have a *script code* additional keys are added to the returned dictionary. .. code:: python >>> import locales >>> engine_locales = locales.build_engine_locales(['en', 'en-US', 'zh', 'zh-CN', 'zh-TW']) >>> engine_locales { 'en': 'en', 'en-US': 'en-US', 'zh': 'zh', 'zh-CN': 'zh-CN', 'zh_Hans': 'zh-CN', 'zh-TW': 'zh-TW', 'zh_Hant': 'zh-TW' } >>> get_engine_locale('zh-Hans', engine_locales) 'zh-CN' This function is a good example to understand the language/region model of SearXNG: SearXNG only distinguishes between **search languages** and **search regions**, by adding the *script-tags*, languages with *script-tags* can be assigned to the **regions** that SearXNG supports. """ engine_locales = {} for tag in tag_list: locale = get_locale(tag) if locale is None: logger.warning("build_engine_locales: skip locale tag %s / unknown by babel", tag) continue if locale.territory: engine_locales[region_tag(locale)] = tag if locale.script: engine_locales[language_tag(locale)] = tag else: engine_locales[language_tag(locale)] = tag return engine_locales