filtering the passed language on the backend

cms/api.py

@@ -9,7 +9,11 @@
 from wagtail.models import Page, Site
 
 from cms import models as cms_models
-from cms.constants import CERTIFICATE_INDEX_SLUG, ENTERPRISE_PAGE_SLUG, CatalogSorting
+from cms.constants import (
+    CERTIFICATE_INDEX_SLUG,
+    ENTERPRISE_PAGE_SLUG,
+    CatalogSorting,
+)
 
 log = logging.getLogger(__name__)
 DEFAULT_HOMEPAGE_PROPS = dict(title="Home Page", subhead="This is the home page")  # noqa: C408
@@ -47,6 +51,7 @@ def filter_and_sort_catalog_pages(
         external_course_pages (iterable of ExternalCoursePage): ExternalCoursePages to filter and sort
         external_program_pages (iterable of ExternalProgramPage): ExternalProgramPages to filter and sort
         sort_by (str): Sorting applicable.
+        language_filter (str): Language filter applicable.
 
     Returns:
         tuple of (list of Pages): A tuple containing a list of combined ProgramPages, CoursePages, ExternalCoursePages and ExternalProgramPages, a list of

cms/models.py

@@ -520,6 +520,7 @@ def get_context(self, request, *args, **kwargs):  # noqa: ARG002
         Populate the context with live programs, courses and programs + courses
         """
         topic_filter = request.GET.get("topic", ALL_TOPICS)
+        language_filter = request.GET.get("language", ALL_LANGUAGES)
 
         is_language_filter_enabled = is_enabled(CATALOG_LANGUAGE_FILTER, default=False)
 
@@ -562,10 +563,19 @@ def get_context(self, request, *args, **kwargs):  # noqa: ARG002
             .order_by("title")
         )
 
+        if language_filter != ALL_LANGUAGES:
+            program_page_qset = program_page_qset.filter(language__name=language_filter)
+            external_program_qset = external_program_qset.filter(
+                language__name=language_filter
+            )
+            course_page_qset = course_page_qset.filter(language__name=language_filter)
+            external_course_qset = external_course_qset.filter(
+                language__name=language_filter
+            )
+
         if topic_filter != ALL_TOPICS:
             program_page_qset = program_page_qset.related_pages(topic_filter)
             external_program_qset = external_program_qset.related_pages(topic_filter)
-
             course_page_qset = course_page_qset.related_pages(topic_filter)
             external_course_qset = external_course_qset.related_pages(topic_filter)