snapshot of https://github.com/zulip/zulip.git @ 48c69911c7dd4e03b20552eb3bd77ad8151c1357 (2026-09-15)

zerver/lib/i18n.py

@@ -0,0 +1,109 @@
+# See https://zulip.readthedocs.io/en/latest/translating/internationalization.html
+
+import logging
+import os
+from functools import lru_cache
+from typing import Any
+
+import orjson
+from django.conf import settings
+from django.http import HttpRequest
+from django.utils import translation
+from django.utils.translation.trans_real import parse_accept_lang_header
+
+from zerver.lib.request import RequestNotes
+from zerver.models import Realm
+
+
+@lru_cache(None)
+def get_language_list() -> list[dict[str, Any]]:
+    path = os.path.join(settings.DEPLOY_ROOT, "locale", "language_name_map.json")
+    with open(path, "rb") as reader:
+        languages = orjson.loads(reader.read())
+        return languages["name_map"]
+
+
+def get_language_name(code: str) -> str:
+    for lang in get_language_list():
+        if code in (lang["code"], lang["locale"]):
+            return lang["name"]
+    # Log problem, but still return a name
+    logging.error("Unknown language code '%s'", code)
+    return "Unknown"
+
+
+def get_available_language_codes() -> list[str]:
+    language_list = get_language_list()
+    codes = [
+        language["code"]
+        for language in language_list
+        if language["code"] == "en" or language["percent_translated"] >= 5
+    ]
+    return codes
+
+
+def get_language_translation_data(language: str) -> dict[str, str]:
+    if language == "en":
+        return {}
+    locale = translation.to_locale(language)
+    path = os.path.join(settings.DEPLOY_ROOT, "locale", locale, "translations.json")
+    try:
+        with open(path, "rb") as reader:
+            return orjson.loads(reader.read())
+    except FileNotFoundError:
+        print(f"Translation for {language} not found at {path}")
+        return {}
+
+
+def get_and_set_request_language(
+    request: HttpRequest, user_configured_language: str, testing_url_language: str | None = None
+) -> str:
+    # We pick a language for the user as follows:
+    # * First priority is the language in the URL, for debugging.
+    # * If not in the URL, we use the language from the user's settings.
+    request_language = testing_url_language
+    if request_language is None:
+        request_language = user_configured_language
+    translation.activate(request_language)
+
+    # We also want to save the language to the user's cookies, so that
+    # something reasonable will happen in logged-in portico pages.
+    # We accomplish that by setting a flag on the request which signals
+    # to LocaleMiddleware to set the cookie on the response.
+    RequestNotes.get_notes(request).set_language = translation.get_language()
+
+    return request_language
+
+
+def get_browser_language_code(request: HttpRequest) -> str | None:
+    accept_lang_header = request.headers.get("Accept-Language")
+    if accept_lang_header is None:
+        return None
+
+    available_language_codes = get_available_language_codes()
+    for accept_lang, priority in parse_accept_lang_header(accept_lang_header):
+        if accept_lang == "*":
+            return None
+        if accept_lang in available_language_codes:
+            return accept_lang
+    return None
+
+
+def get_default_language_for_new_user(realm: Realm, *, request: HttpRequest | None) -> str:
+    if request is None:
+        # Users created via the API or LDAP will not have a
+        # browser/request associated with them, and should just use
+        # the realm's default language.
+        return realm.default_language
+
+    browser_language_code = get_browser_language_code(request)
+    if browser_language_code is not None:
+        return browser_language_code
+    return realm.default_language
+
+
+def get_default_language_for_anonymous_user(request: HttpRequest) -> str:
+    browser_language_code = get_browser_language_code(request)
+    if browser_language_code is not None:
+        return browser_language_code
+    return settings.LANGUAGE_CODE