Fix translation of file types in CWS

cms/conf.py

@@ -140,12 +140,6 @@ def __init__(self):
         self.max_input_length = 5_000_000  # 5 MB
         self.stl_path = "/usr/share/cppreference/doc/html/"
         self.docs_path = None
-        # Prefix of 'shared-mime-info'[1] installation. It can be found
-        # out using `pkg-config --variable=prefix shared-mime-info`, but
-        # it's almost universally the same (i.e. '/usr') so it's hardly
-        # necessary to change it.
-        # [1] http://freedesktop.org/wiki/Software/shared-mime-info
-        self.shared_mime_info_prefix = "/usr"
         self.contest_admin_token = None
 
         # AdminWebServer.

cms/locale/locale.py

@@ -33,7 +33,6 @@
 import copy
 import logging
 import math
-import os
 
 import babel.core
 import babel.dates
@@ -43,8 +42,8 @@
 import babel.units
 import importlib.resources
 
-from cms import config
 from cmscommon.datetime import utc
+from cmscommon.mimetypes import get_name_for_type
 from datetime import datetime, tzinfo, timedelta
 
 
@@ -70,9 +69,6 @@ def __init__(self, lang_code, mofile=None):
             self.translation = babel.support.Translations(mofile, domain="cms")
         else:
             self.translation = babel.support.NullTranslations()
-        self.mimetype_translation = babel.support.Translations.load(
-            os.path.join(config.shared_mime_info_prefix, "share", "locale"),
-            [self.locale], "shared-mime-info")
 
     @property
     def identifier(self) -> str:
@@ -266,7 +262,11 @@ def format_locale(self, code: str) -> str:
             return code
 
     def translate_mimetype(self, mimetype: str) -> str:
-        return self.mimetype_translation.gettext(mimetype)
+        lang_code = self.identifier
+        alt_lang_code = babel.core.get_locale_identifier(
+            (self.locale.language, self.locale.territory), sep="_"
+        )
+        return get_name_for_type(mimetype, lang_code, alt_lang_code)
 
 
 DEFAULT_TRANSLATION = Translation("en")

cms/server/contest/templates/task_description.html

@@ -177,10 +177,8 @@ <h2>{% trans %}Attachments{% endtrans %}</h2>
     {% for filename, attachment in task.attachments|dictsort(by="key") %}
         {% set mime_type = get_mimetype_for_file_name(filename) %}
         {% if mime_type is not none %}
-            {% set type_name = get_name_for_mimetype(mime_type) %}
             {% set type_icon = get_icon_for_mimetype(mime_type) %}
         {% else %}
-            {% set type_name = none %}
             {% set type_icon = none %}
         {% endif %}
         {% set file_size = handler.application.service.file_cacher.get_size(attachment.digest) %}
@@ -195,8 +193,8 @@ <h2>{% trans %}Attachments{% endtrans %}</h2>
                         <span class="name">{{ filename }}</span>
                         <span class="size">{{ file_size|format_size }}</span>
                     </span>
-            {% if type_name is not none %}
-                    <span class="type">{{ translation.translate_mimetype(type_name) }}</span>
+            {% if mime_type is not none %}
+                    <span class="type">{{ translation.translate_mimetype(mime_type) }}</span>
             {% endif %}
                 </a>
             </li>

cms/server/jinja2_toolbox.py

@@ -42,8 +42,7 @@
 from cmscommon.constants import \
     SCORE_MODE_MAX, SCORE_MODE_MAX_SUBTASK, SCORE_MODE_MAX_TOKENED_LAST
 from cmscommon.datetime import make_datetime, make_timestamp, utc, local_tz
-from cmscommon.mimetypes import get_type_for_file_name, get_name_for_type, \
-    get_icon_for_type
+from cmscommon.mimetypes import get_type_for_file_name, get_icon_for_type
 
 
 @contextfilter
@@ -211,7 +210,6 @@ def instrument_cms_toolbox(env: Environment):
     env.globals["get_score_type"] = safe_get_score_type
 
     env.globals["get_mimetype_for_file_name"] = get_type_for_file_name
-    env.globals["get_name_for_mimetype"] = get_name_for_type
     env.globals["get_icon_for_mimetype"] = get_icon_for_type
 
     env.filters["to_language"] = get_language

cmscommon/mimetypes.py

@@ -16,10 +16,12 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import functools
 import os.path
 
 import xdg.BaseDirectory
 import xdg.Mime
+import xdg.Locale
 
 
 __all__ = [
@@ -59,17 +61,36 @@ def get_icon_for_type(typename: str) -> str:
         return _icons[typename]
     return mimetype.media + "-x-generic"
 
-
-def get_name_for_type(typename: str) -> str:
+# xdg.Mime is by default memoized, but since we need to change the language, we
+# need to wipe the cache to load the correct language. So use our own caching
+# on top of it.
+@functools.cache
+def get_name_for_type(typename: str, language: str, alt_language: str) -> str:
     """Get the natural language description of the MIME type.
 
     typename: a MIME type, e.g., "application/pdf".
+    language: the BCP47 code of the language for which to return the result.
+    alt_language: underscore-separated form of the language code, to work
+        around incorrect behavior in pyxdg.
 
     return: the human-readable description (also called comment)
         of the given MIME type, e.g., "PDF document".
 
     """
+    # pyxdg expects the locale field to be provided as a posix-style locale
+    # name, e.g. zh_CN. It assumes this in both the provided language name, and
+    # in the xml:lang attribute of the mimetype xml files. Some distributions
+    # instead use BCP47 language codes, e.g. zh-Hans-CN, in the mimetype xml
+    # files (which is semantically more correct, as this is mandated by the xml
+    # spec).
+    # First parse the language from the posix format.
+    xdg.Locale.update(alt_language)
+    # Then, we make pyxdg think the BCP47 code is another variant of the
+    # current language name.
+    xdg.Locale.langs += [language]
     mimetype = xdg.Mime.lookup(typename).canonical()
+    # Force reloading the comment, because the language might have changed.
+    mimetype._comment = None
     return mimetype.get_comment()
 
 

cmstestsuite/unit_tests/cmscommon/mimetypes_test.py

@@ -42,11 +42,11 @@ def test_generic(self):
 class TestGetNameForType(unittest.TestCase):
 
     def test_basic(self):
-        self.assertEqual(get_name_for_type("application/pdf"),
+        self.assertEqual(get_name_for_type("application/pdf", "en", "en"),
                          "PDF document")
 
     def test_alias(self):
-        self.assertEqual(get_name_for_type("text/x-octave"),
+        self.assertEqual(get_name_for_type("text/x-octave", "en", "en"),
                          "MATLAB file")
 
 

cmstestsuite/unit_tests/locale/locale_test.py

@@ -53,6 +53,7 @@
 ITALIAN = Translation("it")
 DANISH = Translation("da")
 CHINESE = Translation("zh_CN")
+CHINESE_TRADITIONAL = Translation("zh_TW")
 
 
 class TestIdentifier(unittest.TestCase):
@@ -591,20 +592,15 @@ def test_localized_decimal_and_thousands_separators(self):
 
 class TestTranslateMimetype(unittest.TestCase):
 
-    @unittest.skipIf(not os.path.isfile(
-        "/usr/share/locale/it/LC_MESSAGES/shared-mime-info.mo"),
-        reason="need Italian shared-mime-info translation")
     def test_translate_mimetype(self):
-        self.assertEqual(ENGLISH.translate_mimetype("PDF document"),
+        self.assertEqual(ENGLISH.translate_mimetype("application/pdf"),
                          "PDF document")
-        self.assertEqual(ITALIAN.translate_mimetype("PDF document"),
+        self.assertEqual(ITALIAN.translate_mimetype("application/pdf"),
                          "Documento PDF")
-
-    def test_graceful_failure(self):
-        self.assertEqual(ENGLISH.translate_mimetype("Not a MIME type"),
-                         "Not a MIME type")
-        self.assertEqual(ITALIAN.translate_mimetype("Not a MIME type"),
-                         "Not a MIME type")
+        self.assertEqual(CHINESE.translate_mimetype("application/pdf"),
+                         "PDF 文档")
+        self.assertEqual(CHINESE_TRADITIONAL.translate_mimetype("application/pdf"),
+                         "PDF 文件")
 
 
 class TestFilterLanguageCodes(unittest.TestCase):

docs/Installation.rst

@@ -70,7 +70,7 @@ On Ubuntu 24.04, one will need to run the following script as root to satisfy al
         postgresql postgresql-client \
         python3.12 python3.12-dev python3-pip python3-venv \
         libpq-dev libcups2-dev libyaml-dev libffi-dev \
-        cppreference-doc-en-html zip curl
+        shared-mime-info cppreference-doc-en-html zip curl
 
     # Isolate from upstream package repository
     echo 'deb [arch=amd64 signed-by=/etc/apt/keyrings/isolate.asc] http://www.ucw.cz/isolate/debian/ noble-isolate main' >/etc/apt/sources.list.d/isolate.list
@@ -92,7 +92,8 @@ On Arch Linux, run the following commands as root to install almost all dependen
 .. sourcecode:: bash
 
     pacman -S base-devel jdk8-openjdk fpc postgresql postgresql-client \
-        python python-pip postgresql-libs libcups libyaml
+        python python-pip postgresql-libs libcups libyaml \
+        shared-mime-info
 
     # Install the following from AUR.
     # https://aur.archlinux.org/packages/cppreference/