Restructure our python module. A lot.

src/pretix/base/middleware.py

@@ -0,0 +1,107 @@
+import pytz
+
+from django.conf import settings
+from django.middleware.locale import LocaleMiddleware as BaseLocaleMiddleware
+from django.utils.translation.trans_real import (
+    get_supported_language_variant,
+    parse_accept_lang_header,
+    language_code_re,
+    check_for_language
+)
+from django.utils.translation import LANGUAGE_SESSION_KEY
+from django.utils import translation, timezone
+from collections import OrderedDict
+from django.utils.cache import patch_vary_headers
+
+
+_supported = None
+
+
+class LocaleMiddleware(BaseLocaleMiddleware):
+
+    """
+    This middleware sets the correct locale and timezone
+    for a request.
+    """
+
+    def process_request(self, request):
+        language = get_language_from_request(request)
+        translation.activate(language)
+        request.LANGUAGE_CODE = translation.get_language()
+
+        tzname = None
+        if request.user.is_authenticated():
+            tzname = request.user.timezone
+        if hasattr(request, 'event'):
+            tzname = request.event.timezone
+        if tzname:
+            try:
+                timezone.activate(pytz.timezone(tzname))
+            except pytz.UnknownTimeZoneError:
+                pass
+        else:
+            timezone.deactivate()
+
+    def process_response(self, request, response):
+        language = translation.get_language()
+        patch_vary_headers(response, ('Accept-Language',))
+        if 'Content-Language' not in response:
+            response['Content-Language'] = language
+        return response
+
+
+def get_language_from_request(request) -> str:
+    """
+    Analyzes the request to find what language the user wants the system to
+    show. Only languages listed in settings.LANGUAGES are taken into account.
+    If the user requests a sublanguage where we have a main language, we send
+    out the main language.
+    """
+    global _supported
+    if _supported is None:
+        _supported = OrderedDict(settings.LANGUAGES)
+
+    # Priority 1: User settings
+    if request.user.is_authenticated():
+        lang_code = request.user.locale
+        if lang_code in _supported and lang_code is not None and check_for_language(lang_code):
+            return lang_code
+
+    # Priority 2: Anonymous user settings (session, cookie)
+    if hasattr(request, 'session'):
+        lang_code = request.session.get(LANGUAGE_SESSION_KEY)
+        if lang_code in _supported and lang_code is not None and check_for_language(lang_code):
+            return lang_code
+
+    lang_code = request.COOKIES.get(settings.LANGUAGE_COOKIE_NAME)
+    try:
+        return get_supported_language_variant(lang_code)
+    except LookupError:
+        pass
+
+    # Priority 3: Event default
+    if hasattr(request, 'event'):
+        lang_code = request.event.locale
+        try:
+            return get_supported_language_variant(lang_code)
+        except LookupError:
+            pass
+
+    # Priority 4: Browser default
+    accept = request.META.get('HTTP_ACCEPT_LANGUAGE', '')
+    for accept_lang, unused in parse_accept_lang_header(accept):
+        if accept_lang == '*':
+            break
+
+        if not language_code_re.search(accept_lang):
+            continue
+
+        try:
+            return get_supported_language_variant(accept_lang)
+        except LookupError:
+            continue
+
+    try:
+        return get_supported_language_variant(settings.LANGUAGE_CODE)
+    except LookupError:
+        return settings.LANGUAGE_CODE