i18n: Pass translation data in page_params.

This is a preliminary step to make translation_data available as a
resource to `i18next.init()`.

zerver/lib/i18n.py

@@ -77,3 +77,18 @@ def get_available_language_codes() -> List[str]:
     language_list = get_language_list()
     codes = [language['code'] for language in language_list]
     return codes
+
+def get_language_translation_data(language: str) -> Dict[str, str]:
+    if language == 'zh-hans':
+        language = 'zh_Hans'
+    elif language == 'zh-hant':
+        language = 'zh_Hant'
+    elif language == 'id-id':
+        language = 'id_ID'
+    path = os.path.join(settings.STATIC_ROOT, 'locale', language, 'translations.json')
+    try:
+        with open(path, 'r') as reader:
+            return ujson.load(reader)
+    except FileNotFoundError:
+        print('Translation for {} not found at {}'.format(language, path))
+        return {}

zerver/tests/test_home.py

@@ -170,6 +170,7 @@ class HomeTest(ZulipTestCase):
             "test_suite",
             "timezone",
             "translate_emoticons",
+            "translation_data",
             "twenty_four_hour_time",
             "two_fa_enabled",
             "two_fa_enabled_user",
@@ -752,3 +753,15 @@ class HomeTest(ZulipTestCase):
         idle_user_msg_list = get_user_messages(long_term_idle_user)
         self.assertEqual(idle_user_msg_list[-1].content, message)
         self.logout()
+
+    def test_translation_data(self) -> None:
+        user = self.example_user("hamlet")
+        user.default_language = 'es'
+        user.save()
+        self.login(user.email)
+        result = self._get_home_page()
+        self.assertEqual(result.status_code, 200)
+
+        # TODO: Ideally, this should validate something about the translation
+        # data, but that requires parsing page_param from the HTML or doing
+        # more complex interception, which we haven't found worth doing.

zerver/views/home.py

@@ -21,7 +21,7 @@ from zerver.lib.actions import update_user_presence, do_change_tos_version, \
     do_update_pointer, realm_user_count
 from zerver.lib.avatar import avatar_url
 from zerver.lib.i18n import get_language_list, get_language_name, \
-    get_language_list_for_templates
+    get_language_list_for_templates, get_language_translation_data
 from zerver.lib.json_encoder_for_html import JSONEncoderForHTML
 from zerver.lib.push_notifications import num_push_devices_for_user
 from zerver.lib.streams import access_stream_by_name
@@ -244,6 +244,10 @@ def home_real(request: HttpRequest) -> HttpResponse:
 
     request._log_data['extra'] = "[%s]" % (register_ret["queue_id"],)
 
+    page_params['translation_data'] = {}
+    if not default_language == 'en':
+        page_params['translation_data'] = get_language_translation_data(translation.get_language())
+
     csp_nonce = generate_random_token(48)
     response = render(request, 'zerver/app/index.html',
                       context={'user_profile': user_profile,