Optimized js i18n of DataTable and FullCalendar.

course/templates/course/calendar.html

@@ -14,7 +14,9 @@
   <script src='{% static "fullcalendar/dist/fullcalendar.js" %}'></script>
   {# load calendar with local language #}
   {% get_current_language as LANGUAGE_CODE %}
-  <script src='{% static "fullcalendar/dist/lang/" %}{{ LANGUAGE_CODE }}.js'></script>
+  {% if LANGUAGE_CODE != "en" %}
+    <script src='{% static "fullcalendar/dist/lang/" %}{{ LANGUAGE_CODE |js_lang_fallback:"fullcalendar" }}.js'></script>
+  {% endif %}
 {% endblock %}
 
 {% block content %}

course/templates/course/gradebook-by-opp.html

@@ -225,7 +225,7 @@ <h3 class="start-well-title">{% trans "Modify many sessions at once" %}</h3>
         "paging": false,
         "ordering": true,
         "columnDefs": [{ type: 'name', targets: 1 }],
-        "language": {url: '{% static "datatables.net-plugins/i18n/" %}{{LANG}}.lang'},
+        "language": {url: '{% static "datatables-i18n/i18n/" %}{{LANG}}.json'},
     } );
     new $.fn.dataTable.FixedColumns(tbl);
   </script>

course/templates/course/gradebook-opp-list.html

@@ -76,7 +76,7 @@ <h1>{% trans "List of Grading Opportunities" %}</h1>
         "scrollCollapse": true,
         "paging": false,
         "ordering": true,
-        "language": {url: '{% static "datatables.net-plugins/i18n/" %}{{LANG}}.lang'},
+        "language": {url: '{% static "datatables-i18n/i18n/" %}{{LANG}}.json'},
     } );
   </script>
 

course/templates/course/gradebook-participant.html

@@ -95,7 +95,7 @@ <h1>{% trans "Grades" %}</h1>
         "scrollCollapse": true,
         "paging": false,
         "columnDefs": [{ type: 'name', targets: 1 }],
-        "language": {url: '{% static "datatables.net-plugins/i18n/" %}{{LANG}}.lang'},
+        "language": {url: '{% static "datatables-i18n/i18n/" %}{{LANG}}.json'},
     } );
   </script>
 

course/templates/course/gradebook.html

@@ -77,7 +77,7 @@ <h1>{% trans "Grade book" %}</h1>
         "paging": true,
         "ordering": true,
         "columnDefs": [{ type: 'name', targets: 1 }],
-        "language": {url: '{% static "datatables.net-plugins/i18n/" %}{{LANG}}.lang'},
+        "language": {url: '{% static "datatables-i18n/i18n/" %}{{LANG}}.json'},
     } );
     new $.fn.dataTable.FixedColumns(tbl);
   </script>

course/templates/course/participation-table.html

@@ -64,6 +64,6 @@
       "paging": false,
       "ordering": true,
       "columnDefs": [{ type: 'name', targets: 1 }],
-      "language": {url: '{% static "datatables.net-plugins/i18n/" %}{{LANG}}.lang'},
+      "language": {url: '{% static "datatables-i18n/i18n/" %}{{LANG}}.json'},
   } );
 </script>

course/templatetags/coursetags.py

@@ -24,20 +24,20 @@
 
 from django.template import Library, Node, TemplateSyntaxError
 from django.utils import translation
-from relate.utils import to_datatables_lang_name
 
 register = Library()
 
-# {{{ get language_code in JS traditional naming format
 
+# {{{ get language_code in JS traditional naming format
 
 class GetCurrentLanguageJsFmtNode(Node):
     def __init__(self, variable):
         self.variable = variable
 
     def render(self, context):
-        datatables_lang_name = to_datatables_lang_name(translation.get_language())
-        context[self.variable] = datatables_lang_name
+        lang_name = (
+            translation.to_locale(translation.get_language()).replace("_", "-"))
+        context[self.variable] = lang_name
         return ''
 
 
@@ -46,9 +46,10 @@ def do_get_current_js_lang_name(parser, token):
     """
     This will store the current language in the context, in js lang format.
     This is different with built-in do_get_current_language, which returns
-    languange name like "en-us", "zh-cn", with the country code using lower
-    case. This method return lang name "en-US", "zh-CN", as most js packages
-    with i18n are providing translations using that naming format.
+    languange name like "en-us", "zh-hans". This method return lang name
+    "en-US", "zh-Hans",  with the country code capitallized if country code
+    has 2 characters, and capitalize first if country code has more than 2
+    characters.
 
     Usage::
 
@@ -65,6 +66,25 @@ def do_get_current_js_lang_name(parser, token):
                 "'as variable' (got %r)" % args)
     return GetCurrentLanguageJsFmtNode(args[2])
 
+
+@register.filter(name='js_lang_fallback')
+def js_lang_fallback(lang_name, js_name=None):
+    """
+    Return the fallback lang name for js files.
+    :param a :class:`str:`
+    :param js_name: a :class:`str:`, optional.
+    :return: a :class:`str:`
+    """
+
+    # The mapping is crap, we use a special case table to fix it.
+    if js_name == "fullcalendar":
+        known_fallback_mapping = {
+            "zh-hans": "zh-cn",
+            "zh-hant": "zh-tw"}
+        return known_fallback_mapping.get(lang_name.lower(), lang_name).lower()
+
+    return lang_name
+
 # }}}
 
 

package.json

@@ -7,7 +7,7 @@
     "datatables.net-bs": "^1.10.16",
     "datatables.net-fixedcolumns": "^3.2.4",
     "datatables.net-fixedcolumns-bs": "^3.2.4",
-    "datatables.net-plugins": "^1.10.15",
+    "datatables-i18n": "git+https://github.com/dzhuang/datatables-i18n.git",
     "font-awesome": "^4.7.0",
     "fullcalendar": "^2.9.1",
     "jquery": "^3.3.1",

relate/utils.py

@@ -31,7 +31,6 @@
 import django.forms as forms
 from django.utils.translation import ugettext_lazy as _
 import dulwich.repo
-import pycountry
 
 from typing import Union
 
@@ -369,29 +368,6 @@ def dumpstacks(signal, frame):
 # }}}
 
 
-# {{{ convert django language name to js styled language name
-
-def to_datatables_lang_name(dj_lang_name):
-    """
-    Turns a Django language name (en-us) into the correspnding DataTables.net
-    i18n lang name.
-    """
-    # The mapping is crap, we use a special case table to fix it.
-    mapping = {"zh-hans": "Chinese",
-               "zh-hant": "Chinese-traditional"}
-
-    if dj_lang_name in mapping:
-        return mapping[dj_lang_name]
-    else:
-        primary = dj_lang_name.split('-')[0]
-        try:
-            return pycountry.languages.get(alpha_2=primary).name
-        except LookupError:
-            return "English"
-
-# }}}
-
-
 #{{{ Allow multiple email connections
 # https://gist.github.com/niran/840999
 

requirements.txt

@@ -62,9 +62,6 @@ unicodecsv
 # To support network matching for facility recognition
 ipaddress
 
-# For datatables i18n
-pycountry
-
 # {{{ For interoperation with SAML2/Shibboleth
 
 pysaml2

setup.py

@@ -30,7 +30,6 @@
           "nbconvert>=5.2.1",
           "pymbolic",
           "sympy",
-          "pycountry",
           ],
       package_data={
           "relate": [

tests/test_misc.py

@@ -277,13 +277,25 @@ def test_get_current_js_lang_name_tag(self):
             template = self.engines["django"].from_string(
                 "{% get_current_js_lang_name as LANG %}{{LANG}}")
             text = template.render()
-            self.assertEqual(text, "English")
+            self.assertEqual(text, "en-US")
 
         with override_settings(LANGUAGE_CODE="de"):
             template = self.engines["django"].from_string(
                 "{% get_current_js_lang_name as LANG %}{{LANG}}")
             text = template.render()
-            self.assertEqual(text, "German")
+            self.assertEqual(text, "de")
+
+        with override_settings(LANGUAGE_CODE="zh-hans"):
+            template = self.engines["django"].from_string(
+                "{% get_current_js_lang_name as LANG %}{{LANG}}")
+            text = template.render()
+            self.assertEqual(text, "zh-Hans")
+
+        with override_settings(LANGUAGE_CODE="zh-hant"):
+            template = self.engines["django"].from_string(
+                "{% get_current_js_lang_name as LANG %}{{LANG}}")
+            text = template.render()
+            self.assertEqual(text, "zh-Hant")
 
     def test_get_current_js_lang_name_tag_failed(self):
         from django.template import TemplateSyntaxError
@@ -307,6 +319,49 @@ def test_get_current_js_lang_name_tag_failed(self):
             self.engines["django"].from_string(
                 "{% get_current_js_lang_name AS LANG %}{{LANG}}")
 
+    def test_js_lang_fallback(self):
+        with override_settings(LANGUAGE_CODE="en-us"):
+            template = self.engines["django"].from_string(
+                "{% get_current_js_lang_name as LANG %}"
+                "{{LANG|js_lang_fallback}}")
+            text = template.render()
+            self.assertEqual(text, "en-US")
+
+        with override_settings(LANGUAGE_CODE="en-us"):
+            template = self.engines["django"].from_string(
+                "{% get_current_js_lang_name as LANG %}"
+                "{{LANG|js_lang_fallback:'fullcalendar'}}")
+            text = template.render()
+            self.assertEqual(text, "en-us")
+
+        with override_settings(LANGUAGE_CODE="zh-cn"):
+            template = self.engines["django"].from_string(
+                "{% get_current_js_lang_name as LANG %}"
+                "{{LANG|js_lang_fallback:'fullcalendar'}}")
+            text = template.render()
+            self.assertEqual(text, "zh-cn")
+
+        with override_settings(LANGUAGE_CODE="zh-cn"):
+            template = self.engines["django"].from_string(
+                "{% get_current_js_lang_name as LANG %}"
+                "{{LANG|js_lang_fallback}}")
+            text = template.render()
+            self.assertEqual(text, "zh-CN")
+
+        with override_settings(LANGUAGE_CODE="zh-hans"):
+            template = self.engines["django"].from_string(
+                "{% get_current_js_lang_name as LANG %}"
+                "{{LANG|js_lang_fallback}}")
+            text = template.render()
+            self.assertEqual(text, "zh-Hans")
+
+        with override_settings(LANGUAGE_CODE="zh-hans"):
+            template = self.engines["django"].from_string(
+                "{% get_current_js_lang_name as LANG %}"
+                "{{LANG|js_lang_fallback:'fullcalendar'}}")
+            text = template.render()
+            self.assertEqual(text, "zh-cn")
+
 
 class HasPermissionTemplateFilterTest(SingleCourseTestMixin, TestCase):
     def setUp(self):