[mod] replace searx.languages by searx.sxng_locales

With the language and region tags from the EngineTraitsMap the handling of
SearXNG's tags of languages and regions has been normalized and is no longer
a *mystery*.  The "languages" became "locales" that are supported by babel and
by this, the update_engine_traits.py can be simplified a lot.

Other code places can be simplified as well, but these simplifications
should (respectively can) only be done when none of the engines work with the
deprecated EngineTraits.supported_languages interface anymore.

This commit replaces searx.languages by searx.sxng_locales and fix the naming of
some names from "language" to "locale" (e.g. language_codes --> sxng_locales).

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

2 files changed, 124 insertions, 262 deletions

diff --git a/searxng_extra/update/update_engine_traits.py b/searxng_extra/update/update_engine_traits.py
index 9630d6d2..7449912d 100755
--- a/searxng_extra/update/update_engine_traits.py
+++ b/searxng_extra/update/update_engine_traits.py
@@ -18,40 +18,52 @@ the :origin:`CI Update data ... <.github/workflows/data-update.yml>`
 from unicodedata import lookup
 from pathlib import Path
 from pprint import pformat
-from babel import Locale, UnknownLocaleError
-from babel.languages import get_global
-from babel.core import parse_locale
+import babel
 
 from searx import settings, searx_dir
 from searx import network
-from searx.engines import load_engines, engines
+from searx.engines import load_engines
 from searx.enginelib.traits import EngineTraitsMap
 
 # Output files.
-languages_file = Path(searx_dir) / 'languages.py'
+languages_file = Path(searx_dir) / 'sxng_locales.py'
+languages_file_header = """\
+# -*- coding: utf-8 -*-
+'''List of SearXNG's locale codes.
 
+This file is generated automatically by::
 
-def fetch_traits_map():
-    """Fetchs supported languages for each engine and writes json file with those."""
-    network.set_timeout_for_thread(10.0)
-
-    def log(msg):
-        print(msg)
+   ./manage pyenv.cmd searxng_extra/update/update_engine_traits.py
+'''
 
-    traits_map = EngineTraitsMap.fetch_traits(log=log)
-    print("fetched properties from %s engines" % len(traits_map))
-    print("write json file: %s" % traits_map.ENGINE_TRAITS_FILE)
-    traits_map.save_data()
-    return traits_map
-
-
-# Get babel Locale object from lang_code if possible.
-def get_locale(lang_code):
-    try:
-        locale = Locale.parse(lang_code, sep='-')
-        return locale
-    except (UnknownLocaleError, ValueError):
-        return None
+sxng_locales = (
+"""
+languages_file_footer = """,
+)
+'''
+A list of five-digit tuples:
+
+0. SearXNG's internal locale tag (a language or region tag)
+1. Name of the language (:py:obj:`babel.core.Locale.get_language_name`)
+2. For region tags the name of the region (:py:obj:`babel.core.Locale.get_territory_name`).
+   Empty string for language tags.
+3. English language name (from :py:obj:`babel.core.Locale.english_name`)
+4. Unicode flag (emoji) that fits to SearXNG's internal region tag. Languages
+   are represented by a globe (\U0001F310)
+
+.. code:: python
+
+   ('en',    'English', '',              'English', '\U0001f310'),
+   ('en-CA', 'English', 'Canada',        'English', '\U0001f1e8\U0001f1e6'),
+   ('en-US', 'English', 'United States', 'English', '\U0001f1fa\U0001f1f8'),
+   ..
+   ('fr',    'Français', '',             'French',  '\U0001f310'),
+   ('fr-BE', 'Français', 'Belgique',     'French',  '\U0001f1e7\U0001f1ea'),
+   ('fr-CA', 'Français', 'Canada',       'French',  '\U0001f1e8\U0001f1e6'),
+
+:meta hide-value:
+'''
+"""
 
 
 lang2emoji = {
@@ -63,249 +75,76 @@ lang2emoji = {
 }
 
 
-def get_unicode_flag(lang_code):
-    """Determine a unicode flag (emoji) that fits to the ``lang_code``"""
+def main():
+    load_engines(settings['engines'])
+    # traits_map = EngineTraitsMap.from_data()
+    traits_map = fetch_traits_map()
+    sxng_tag_list = filter_locales(traits_map)
+    write_languages_file(sxng_tag_list)
 
-    emoji = lang2emoji.get(lang_code.lower())
-    if emoji:
-        return emoji
 
-    if len(lang_code) == 2:
-        return '\U0001F310'
+def fetch_traits_map():
+    """Fetchs supported languages for each engine and writes json file with those."""
+    network.set_timeout_for_thread(10.0)
 
-    language = territory = script = variant = ''
-    try:
-        language, territory, script, variant = parse_locale(lang_code, '-')
-    except ValueError as exc:
-        print(exc)
-
-    # https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2
-    if not territory:
-        # https://www.unicode.org/emoji/charts/emoji-list.html#country-flag
-        emoji = lang2emoji.get(language)
-        if not emoji:
-            print(
-                "%s --> language: %s / territory: %s / script: %s / variant: %s"
-                % (lang_code, language, territory, script, variant)
-            )
-        return emoji
+    def log(msg):
+        print(msg)
 
-    emoji = lang2emoji.get(territory.lower())
-    if emoji:
-        return emoji
+    traits_map = EngineTraitsMap.fetch_traits(log=log)
+    print("fetched properties from %s engines" % len(traits_map))
+    print("write json file: %s" % traits_map.ENGINE_TRAITS_FILE)
+    traits_map.save_data()
+    return traits_map
 
-    try:
-        c1 = lookup('REGIONAL INDICATOR SYMBOL LETTER ' + territory[0])
-        c2 = lookup('REGIONAL INDICATOR SYMBOL LETTER ' + territory[1])
-        # print("%s --> territory: %s --> %s%s" %(lang_code, territory, c1, c2 ))
-    except KeyError as exc:
-        print("%s --> territory: %s --> %s" % (lang_code, territory, exc))
-        return None
 
-    return c1 + c2
+def filter_locales(traits_map: EngineTraitsMap):
+    """Filter language & region tags by a threshold."""
 
+    min_eng_per_region = 11
+    min_eng_per_lang = 13
 
-def get_territory_name(lang_code):
-    country_name = None
-    locale = get_locale(lang_code)
-    try:
-        if locale is not None:
-            country_name = locale.get_territory_name()
-    except FileNotFoundError as exc:
-        print("ERROR: %s --> %s" % (locale, exc))
-    return country_name
-
-
-def join_language_lists(traits_map: EngineTraitsMap):
-    """Join all languages of the engines into one list.  The returned language list
-    contains language codes (``zh``) and region codes (``zh-TW``).  The codes can
-    be parsed by babel::
-
-      babel.Locale.parse(language_list[n])
-    """
-    # pylint: disable=too-many-branches
-    language_list = {}
-
-    for eng_name, eng_traits in traits_map.items():
-        eng = engines[eng_name]
-        eng_codes = set()
-
-        if eng_traits.data_type == 'traits_v1':
-            # items of type 'engine_traits' do have regions & languages, the
-            # list of eng_codes should contain both.
-            eng_codes.update(eng_traits.regions.keys())
-            eng_codes.update(eng_traits.languages.keys())
-
-        elif eng_traits.data_type == 'supported_languages':
-            # vintage / deprecated
-            _codes = set()
-            if isinstance(eng_traits.supported_languages, dict):
-                _codes.update(eng_traits.supported_languages.keys())
-            elif isinstance(eng_traits.supported_languages, list):
-                _codes.update(eng_traits.supported_languages)
-            else:
-                raise TypeError('engine.supported_languages type %s is unknown' % type(eng_traits.supported_languages))
-
-            for lang_code in _codes:
-                # apply custom fixes if necessary
-                if lang_code in getattr(eng, 'language_aliases', {}).values():
-                    lang_code = next(lc for lc, alias in eng.language_aliases.items() if lang_code == alias)
-                eng_codes.add(lang_code)
-
-        for lang_code in eng_codes:
-
-            locale = get_locale(lang_code)
-
-            # ensure that lang_code uses standard language and country codes
-            if locale and locale.territory:
-                lang_code = "{lang}-{country}".format(lang=locale.language, country=locale.territory)
-            short_code = lang_code.split('-')[0]
-
-            # add language without country if not in list
-            if short_code not in language_list:
-                if locale:
-                    # get language's data from babel's Locale object
-                    language_name = locale.get_language_name().title()
-                    english_name = locale.english_name.split(' (')[0]
-                elif short_code in traits_map['wikipedia'].supported_languages:
-                    # get language's data from wikipedia if not known by babel
-                    language_name = traits_map['wikipedia'].supported_languages[short_code]['name']
-                    english_name = traits_map['wikipedia'].supported_languages[short_code]['english_name']
-                else:
-                    language_name = None
-                    english_name = None
-
-                # add language to list
-                language_list[short_code] = {
-                    'name': language_name,
-                    'english_name': english_name,
-                    'counter': set(),
-                    'countries': {},
-                }
-
-            # add language with country if not in list
-            if lang_code != short_code and lang_code not in language_list[short_code]['countries']:
-                country_name = ''
-                if locale:
-                    # get country name from babel's Locale object
-                    try:
-                        country_name = locale.get_territory_name()
-                    except FileNotFoundError as exc:
-                        print("ERROR: %s --> %s" % (locale, exc))
-                        locale = None
-
-                language_list[short_code]['countries'][lang_code] = {
-                    'country_name': country_name,
-                    'counter': set(),
-                }
-
-            # count engine for both language_country combination and language alone
-            language_list[short_code]['counter'].add(eng_name)
-            if lang_code != short_code:
-                language_list[short_code]['countries'][lang_code]['counter'].add(eng_name)
-
-    return language_list
-
-
-# Filter language list so it only includes the most supported languages and countries
-def filter_language_list(joined_languages_map):
-    min_engines_per_lang = 12
-    min_engines_per_country = 7
-    # pylint: disable=consider-using-dict-items, consider-iterating-dictionary
-    main_engines = [
-        engine_name
-        for engine_name in engines.keys()
-        if 'general' in engines[engine_name].categories
-        and hasattr(engines[engine_name], 'supported_languages')
-        and engines[engine_name].supported_languages
-        and not engines[engine_name].disabled
-    ]
-
-    # filter list to include only languages supported by most engines or all default general engines
-    filtered_languages = {
-        code: lang
-        for code, lang in joined_languages_map.items()
-        if (
-            len(lang['counter']) >= min_engines_per_lang
-            or all(main_engine in lang['counter'] for main_engine in main_engines)
-        )
-    }
-
-    def _copy_lang_data(lang, country_name=None):
-        new_dict = {}
-        new_dict['name'] = joined_languages_map[lang]['name']
-        new_dict['english_name'] = joined_languages_map[lang]['english_name']
-        if country_name:
-            new_dict['country_name'] = country_name
-        return new_dict
-
-    # for each language get country codes supported by most engines or at least one country code
-    filtered_languages_with_countries = {}
-    for lang, lang_data in filtered_languages.items():
-        countries = lang_data['countries']
-        filtered_countries = {}
-
-        # get language's country codes with enough supported engines
-        for lang_country, country_data in countries.items():
-            if len(country_data['counter']) >= min_engines_per_country:
-                filtered_countries[lang_country] = _copy_lang_data(lang, country_data['country_name'])
-
-        # add language without countries too if there's more than one country to choose from
-        if len(filtered_countries) > 1:
-            filtered_countries[lang] = _copy_lang_data(lang, None)
-        elif len(filtered_countries) == 1:
-            lang_country = next(iter(filtered_countries))
-
-        # if no country has enough engines try to get most likely country code from babel
-        if not filtered_countries:
-            lang_country = None
-            subtags = get_global('likely_subtags').get(lang)
-            if subtags:
-                country_code = subtags.split('_')[-1]
-                if len(country_code) == 2:
-                    lang_country = "{lang}-{country}".format(lang=lang, country=country_code)
-
-            if lang_country:
-                filtered_countries[lang_country] = _copy_lang_data(lang, None)
-            else:
-                filtered_countries[lang] = _copy_lang_data(lang, None)
-
-        filtered_languages_with_countries.update(filtered_countries)
-
-    return filtered_languages_with_countries
+    _ = {}
+    for eng in traits_map.values():
+        for reg in eng.regions.keys():
+            _[reg] = _.get(reg, 0) + 1
 
+    regions = set(k for k, v in _.items() if v >= min_eng_per_region)
+    lang_from_region = set(k.split('-')[0] for k in regions)
 
-class UnicodeEscape(str):
-    """Escape unicode string in :py:obj:`pprint.pformat`"""
+    _ = {}
+    for eng in traits_map.values():
+        for lang in eng.languages.keys():
+            # ignore script types like zh_Hant, zh_Hans or sr_Latin, pa_Arab (they
+            # already counted by existence of 'zh' or 'sr', 'pa')
+            if '_' in lang:
+                # print("ignore %s" % lang)
+                continue
+            _[lang] = _.get(lang, 0) + 1
 
-    def __repr__(self):
-        return "'" + "".join([chr(c) for c in self.encode('unicode-escape')]) + "'"
+    languages = set(k for k, v in _.items() if v >= min_eng_per_lang)
 
+    sxng_tag_list = set()
+    sxng_tag_list.update(regions)
+    sxng_tag_list.update(lang_from_region)
+    sxng_tag_list.update(languages)
 
-# Write languages.py.
-def write_languages_file(languages):
-    file_headers = (
-        "# -*- coding: utf-8 -*-",
-        "# list of language codes",
-        "# this file is generated automatically by utils/fetch_languages.py",
-        "language_codes = (\n",
-    )
+    return sxng_tag_list
+
+
+def write_languages_file(sxng_tag_list):
 
     language_codes = []
 
-    for code in sorted(languages):
+    for sxng_tag in sorted(sxng_tag_list):
+        sxng_locale: babel.Locale = babel.Locale.parse(sxng_tag, sep='-')
 
-        name = languages[code]['name']
-        if name is None:
-            print("ERROR: languages['%s'] --> %s" % (code, languages[code]))
-            continue
+        flag = get_unicode_flag(sxng_locale) or ''
 
-        flag = get_unicode_flag(code) or ''
         item = (
-            code,
-            languages[code]['name'].split(' (')[0],
-            get_territory_name(code) or '',
-            languages[code].get('english_name') or '',
+            sxng_tag,
+            sxng_locale.get_language_name().title(),
+            sxng_locale.get_territory_name() or '',
+            sxng_locale.english_name.split(' (')[0],
             UnicodeEscape(flag),
         )
 
@@ -314,22 +153,45 @@ def write_languages_file(languages):
     language_codes = tuple(language_codes)
 
     with open(languages_file, 'w', encoding='utf-8') as new_file:
-        file_content = "{file_headers} {language_codes},\n)\n".format(
-            # fmt: off
-            file_headers = '\n'.join(file_headers),
-            language_codes = pformat(language_codes, indent=4)[1:-1]
-            # fmt: on
+        file_content = "{header} {language_codes}{footer}".format(
+            header=languages_file_header,
+            language_codes=pformat(language_codes, width=120, indent=4)[1:-1],
+            footer=languages_file_footer,
         )
         new_file.write(file_content)
         new_file.close()
 
 
-def main():
-    load_engines(settings['engines'])
-    traits_map = fetch_traits_map()
-    joined_languages_map = join_language_lists(traits_map)
-    filtered_languages = filter_language_list(joined_languages_map)
-    write_languages_file(filtered_languages)
+class UnicodeEscape(str):
+    """Escape unicode string in :py:obj:`pprint.pformat`"""
+
+    def __repr__(self):
+        return "'" + "".join([chr(c) for c in self.encode('unicode-escape')]) + "'"
+
+
+def get_unicode_flag(locale: babel.Locale):
+    """Determine a unicode flag (emoji) that fits to the ``locale``"""
+
+    emoji = lang2emoji.get(locale.language)
+    if emoji:
+        return emoji
+
+    if not locale.territory:
+        return '\U0001F310'
+
+    emoji = lang2emoji.get(locale.territory.lower())
+    if emoji:
+        return emoji
+
+    try:
+        c1 = lookup('REGIONAL INDICATOR SYMBOL LETTER ' + locale.territory[0])
+        c2 = lookup('REGIONAL INDICATOR SYMBOL LETTER ' + locale.territory[1])
+        # print("OK   : %s --> %s%s" % (locale, c1, c2))
+    except KeyError as exc:
+        print("ERROR: %s --> %s" % (locale, exc))
+        return None
+
+    return c1 + c2
 
 
 if __name__ == "__main__":
diff --git a/searxng_extra/update/update_osm_keys_tags.py b/searxng_extra/update/update_osm_keys_tags.py
index 72197498..72f3d61c 100755
--- a/searxng_extra/update/update_osm_keys_tags.py
+++ b/searxng_extra/update/update_osm_keys_tags.py
@@ -50,7 +50,7 @@ from pathlib import Path
 from searx import searx_dir
 from searx.network import set_timeout_for_thread
 from searx.engines import wikidata, set_loggers
-from searx.languages import language_codes
+from searx.sxng_locales import sxng_locales
 from searx.engines.openstreetmap import get_key_rank, VALUE_TO_LINK
 
 set_loggers(wikidata, 'wikidata')
@@ -76,7 +76,7 @@ GROUP BY ?key ?item ?itemLabel
 ORDER BY ?key ?item ?itemLabel
 """
 
-LANGUAGES = [l[0].lower() for l in language_codes]
+LANGUAGES = [l[0].lower() for l in sxng_locales]
 
 PRESET_KEYS = {
     ('wikidata',): {'en': 'Wikidata'},