refactor: Remove use of CourseOverview model directly in the Certificates app

[MICROBA-1289]
* Remove use of the CourseOverview model directly in the Certificates app
* Introduce a few new Python API functions in the `course_overview` and `catalog` django apps to replace functionality in the Certificates app.

lms/djangoapps/certificates/api.py

@@ -44,7 +44,6 @@ from lms.djangoapps.certificates.utils import (
     has_html_certificates_enabled as _has_html_certificates_enabled
 )
 from openedx.core.djangoapps.content.course_overviews.api import get_course_overview_or_none
-from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
 
 log = logging.getLogger("edx.certificate")
 User = get_user_model()
@@ -243,7 +242,7 @@ def certificate_downloadable_status(student, course_key):
         'uuid': None,
     }
 
-    course_overview = CourseOverview.get_from_id(course_key)
+    course_overview = get_course_overview_or_none(course_key)
     if (
         not certificates_viewable_for_course(course_overview) and
         CertificateStatuses.is_passing_status(current_status['status']) and

lms/djangoapps/certificates/apis/v0/tests/test_views.py

@@ -396,7 +396,7 @@ class CertificatesListRestApiTest(AuthAndScopesTestMixin, SharedModuleStoreTestC
         expected_download_url = reverse('certificates:render_cert_by_uuid', kwargs=kwargs)
         self.assert_success_response_for_student(response, download_url=expected_download_url)
 
-    @patch('lms.djangoapps.certificates.apis.v0.views.get_course_run_details')
+    @patch('openedx.core.djangoapps.content.course_overviews.api.get_course_run_details')
     def test_certificate_without_course(self, mock_get_course_run_details):
         """
         Verify that certificates are returned for deleted XML courses.

lms/djangoapps/certificates/apis/v0/views.py

@@ -21,8 +21,11 @@ from lms.djangoapps.certificates.api import (
     get_certificates_for_user
 )
 from lms.djangoapps.certificates.apis.v0.permissions import IsOwnerOrPublicCertificates
-from openedx.core.djangoapps.catalog.utils import get_course_run_details
-from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
+from openedx.core.djangoapps.content.course_overviews.api import (
+    get_course_overview_or_none,
+    get_course_overviews_from_ids,
+    get_pseudo_course_overview
+)
 from openedx.core.djangoapps.user_api.accounts.api import visible_fields
 from openedx.core.lib.api.authentication import BearerAuthenticationAllowInactiveUser
 
@@ -97,7 +100,7 @@ class CertificatesDetailView(APIView):
 
     def get(self, request, username, course_id):
         """
-        Gets a certificate information.
+        Retrieves certificate information for a user in a specified course run.
 
         Args:
             request (Request): Django request object.
@@ -123,9 +126,10 @@ class CertificatesDetailView(APIView):
                 data={'error_code': 'no_certificate_for_user'}
             )
 
-        course_overview = CourseOverview.get_from_id(course_id)
+        course_overview = get_course_overview_or_none(course_id)
         # return 404 if it's not a PDF certificates and there is no active certificate configuration.
-        if not user_cert['is_pdf_certificate'] and not course_overview.has_any_active_web_certificate:
+        if not user_cert['is_pdf_certificate'] and (not course_overview or
+                                                    not course_overview.has_any_active_web_certificate):
             return Response(
                 status=404,
                 data={'error_code': 'no_certificate_configuration_for_course'}
@@ -174,7 +178,7 @@ class CertificatesListView(APIView):
         )
     ])
     def get(self, request, username):
-        """Get a paginated list of bookmarks for a user.
+        """Get a paginated list of certificates for a user.
 
         **Use Case**
 
@@ -270,32 +274,22 @@ class CertificatesListView(APIView):
                 passing_certificates[course_key] = course_certificate
 
         viewable_certificates = []
-        for course_key, course_overview in CourseOverview.get_from_ids(
-            list(passing_certificates.keys())
-        ).items():
+        course_ids = list(passing_certificates.keys())
+        course_overviews = get_course_overviews_from_ids(course_ids)
+        for course_key, course_overview in course_overviews.items():
             if not course_overview:
                 # For deleted XML courses in which learners have a valid certificate.
                 # i.e. MITx/7.00x/2013_Spring
-                course_overview = self._get_pseudo_course_overview(course_key)
+                course_overview = get_pseudo_course_overview(course_key)
             if certificates_viewable_for_course(course_overview):
                 course_certificate = passing_certificates[course_key]
                 # add certificate into viewable certificate list only if it's a PDF certificate
                 # or there is an active certificate configuration.
-                if course_certificate['is_pdf_certificate'] or course_overview.has_any_active_web_certificate:
+                if course_certificate['is_pdf_certificate'] or (course_overview and
+                                                                course_overview.has_any_active_web_certificate):
                     course_certificate['course_display_name'] = course_overview.display_name_with_default
                     course_certificate['course_organization'] = course_overview.display_org_with_default
                     viewable_certificates.append(course_certificate)
 
         viewable_certificates.sort(key=lambda certificate: certificate['created'])
         return viewable_certificates
-
-    def _get_pseudo_course_overview(self, course_key):
-        """
-        Returns a pseudo course overview object for deleted courses.
-        """
-        course_run = get_course_run_details(course_key, ['title'])
-        return CourseOverview(
-            display_name=course_run.get('title'),
-            display_org_with_default=course_key.org,
-            certificates_show_before_end=True
-        )

lms/djangoapps/certificates/models.py

@@ -30,7 +30,7 @@ from lms.djangoapps.badges.events.course_complete import course_badge_check
 from lms.djangoapps.badges.events.course_meta import completion_check, course_group_check
 from lms.djangoapps.certificates.data import CertificateStatuses
 from lms.djangoapps.instructor_task.models import InstructorTask
-from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
+from openedx.core.djangoapps.content.course_overviews.api import get_course_overview_or_none
 from openedx.core.djangoapps.signals.signals import COURSE_CERT_AWARDED, COURSE_CERT_CHANGED, COURSE_CERT_REVOKED
 from openedx.core.djangoapps.xmodule_django.models import NoneToEmptyManager
 
@@ -657,7 +657,12 @@ def certificate_info_for_user(user, course_id, grade, user_is_allowlisted, user_
     certificate_type = 'N/A'
     status = certificate_status(user_certificate)
     certificate_generated = status['status'] == CertificateStatuses.downloadable
-    can_have_certificate = CourseOverview.get_from_id(course_id).may_certify()
+
+    can_have_certificate = False
+    course_overview = get_course_overview_or_none(course_id)
+    if course_overview:
+        can_have_certificate = course_overview.may_certify()
+
     enrollment_mode, __ = CourseEnrollment.enrollment_mode_for_user(user, course_id)
     mode_is_verified = enrollment_mode in CourseMode.VERIFIED_MODES
     user_is_verified = grade is not None and mode_is_verified

lms/djangoapps/certificates/views/support.py

@@ -25,7 +25,6 @@ from lms.djangoapps.certificates.api import generate_certificate_task, get_certi
 from lms.djangoapps.certificates.permissions import GENERATE_ALL_CERTIFICATES, VIEW_ALL_CERTIFICATES
 from lms.djangoapps.instructor_task.api import generate_certificates_for_students
 from openedx.core.djangoapps.content.course_overviews.api import get_course_overview_or_none
-from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
 
 log = logging.getLogger(__name__)
 
@@ -113,16 +112,16 @@ def search_certificates(request):
         except InvalidKeyError:
             return HttpResponseBadRequest(_("Course id '{course_id}' is not valid").format(course_id=course_id))
         else:
-            try:
-                if CourseOverview.get_from_id(course_key):
-                    certificates = [certificate for certificate in certificates
-                                    if certificate['course_key'] == course_id]
-                    if not certificates:
-                        return JsonResponse([{'username': user.username, 'course_key': course_id, 'regenerate': False}])
-            except CourseOverview.DoesNotExist:
+            course_overview = get_course_overview_or_none(course_key)
+            if not course_overview:
                 msg = _("The course does not exist against the given key '{course_key}'").format(course_key=course_key)
                 return HttpResponseBadRequest(msg)
 
+            certificates = [certificate for certificate in certificates
+                            if certificate['course_key'] == course_id]
+            if not certificates:
+                return JsonResponse([{'username': user.username, 'course_key': course_id, 'regenerate': False}])
+
     return JsonResponse(certificates)
 
 
@@ -245,26 +244,24 @@ def generate_certificate_for_user(request):
     if response is not None:
         return response
 
-    try:
-        # Check that the course exists
-        CourseOverview.get_from_id(params["course_key"])
-    except CourseOverview.DoesNotExist:
+    course_overview = get_course_overview_or_none(params["course_key"])
+    if not course_overview:
         msg = _("The course {course_key} does not exist").format(course_key=params["course_key"])
         return HttpResponseBadRequest(msg)
-    else:
-        # Check that the user is enrolled in the course
-        if not CourseEnrollment.is_enrolled(params["user"], params["course_key"]):
-            msg = _("User {username} is not enrolled in the course {course_key}").format(
-                username=params["user"].username,
-                course_key=params["course_key"]
-            )
-            return HttpResponseBadRequest(msg)
-
-        # Attempt to generate certificate
-        generate_certificates_for_students(
-            request,
-            params["course_key"],
-            student_set="specific_student",
-            specific_student_id=params["user"].id
+
+    # Check that the user is enrolled in the course
+    if not CourseEnrollment.is_enrolled(params["user"], params["course_key"]):
+        msg = _("User {username} is not enrolled in the course {course_key}").format(
+            username=params["user"].username,
+            course_key=params["course_key"]
         )
-        return HttpResponse(200)
+        return HttpResponseBadRequest(msg)
+
+    # Attempt to generate certificate
+    generate_certificates_for_students(
+        request,
+        params["course_key"],
+        student_set="specific_student",
+        specific_student_id=params["user"].id
+    )
+    return HttpResponse(200)

lms/djangoapps/certificates/views/webview.py

@@ -44,7 +44,7 @@ from lms.djangoapps.certificates.models import (
 )
 from lms.djangoapps.certificates.permissions import PREVIEW_CERTIFICATES
 from lms.djangoapps.certificates.utils import emit_certificate_event, get_certificate_url
-from openedx.core.djangoapps.catalog.utils import get_course_run_details
+from openedx.core.djangoapps.catalog.api import get_course_run_details
 from openedx.core.djangoapps.certificates.api import display_date_for_certificate
 from openedx.core.djangoapps.lang_pref.api import get_closest_released_language
 from openedx.core.djangoapps.site_configuration import helpers as configuration_helpers

openedx/core/djangoapps/catalog/api.py

@@ -5,6 +5,7 @@ Python APIs exposed by the catalog app to other in-process apps.
 from .utils import get_programs_by_type_slug as _get_programs_by_type_slug
 from .utils import get_programs as _get_programs
 from .utils import course_run_keys_for_program as _course_run_keys_for_program
+from .utils import get_course_run_details as _get_course_run_details
 
 
 def get_programs_by_type(site, program_type_slug):
@@ -47,3 +48,16 @@ def get_course_run_key_for_program_from_cache(program):
         (set): A set of Course Run Keys.
     """
     return _course_run_keys_for_program(parent_program=program)
+
+
+def get_course_run_details(course_key, fields_list):
+    """
+    Retrieves course run details for a given course run key.
+
+    Params:
+        course_key (CourseKey): The identifier for the course.
+        fields_list (List, string): A list of fields (as strings) of values we want returned.
+    Returns:
+        dict containing response from the Discovery API that includes the fields specified in `fields_list`
+    """
+    return _get_course_run_details(course_key, fields_list)

openedx/core/djangoapps/catalog/tests/test_api.py

+"""
+Tests for the Catalog apps `api.py` functions.
+"""
+from mock import patch
+
+from django.test import TestCase
+
+from openedx.core.djangoapps.catalog.api import get_course_run_details
+from openedx.core.djangoapps.catalog.tests.factories import CourseRunFactory
+from openedx.core.djangolib.testing.utils import skip_unless_lms
+
+
+@skip_unless_lms
+class TestCatalogApi(TestCase):
+    """
+    Tests for the Catalog apps `api.py` functions.
+    """
+
+    @patch("openedx.core.djangoapps.catalog.api._get_course_run_details")
+    def test_get_course_run_details(self, mock_get_course_run_details):
+        """
+        Test for Python API `get_course_run_details` function.
+        """
+        course_run = CourseRunFactory()
+
+        mock_get_course_run_details.return_value = {
+            'title': course_run['title'],
+        }
+
+        results = get_course_run_details(course_run['key'], ['title'])
+
+        assert results['title'] == course_run['title']

openedx/core/djangoapps/content/course_overviews/api.py

@@ -3,6 +3,7 @@ CourseOverview api
 """
 import logging
 
+from openedx.core.djangoapps.catalog.api import get_course_run_details
 from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
 from openedx.core.djangoapps.content.course_overviews.serializers import (
     CourseOverviewBaseSerializer,
@@ -24,9 +25,41 @@ def get_course_overview_or_none(course_id):
         return None
 
 
+def get_pseudo_course_overview(course_id):
+    """
+    Returns a pseudo course overview object for a deleted course.
+
+    Params:
+        course_id (CourseKey): The identifier for the course.
+    Returns:
+        (Temporary) CourseOverview object representing for a deleted course.
+    """
+    fields = ['title']
+    course_run = get_course_run_details(course_id, fields)
+
+    return CourseOverview(
+        display_name=course_run.get('title'),
+        display_org_with_default=course_id.org,
+        certificates_show_before_end=True
+    )
+
+
+def get_course_overviews_from_ids(course_ids):
+    """
+    Return course overviews for the specified course ids.
+
+    Params:
+        course_ids (iterable[CourseKey])
+
+    Returns:
+        dict[CourseKey, CourseOverview|None]
+    """
+    return CourseOverview.get_from_ids(course_ids)
+
+
 def get_course_overviews(course_ids):
     """
-    Return course_overview data for a given list of opaque_key course_ids.
+    Return (serialized) course_overview data for a given list of opaque_key course_ids.
     """
     overviews = CourseOverview.objects.filter(id__in=course_ids)
     return CourseOverviewBaseSerializer(overviews, many=True).data

openedx/core/djangoapps/content/course_overviews/tests/test_api.py

 """
 course_overview api tests
 """
+from mock import patch
 
 from opaque_keys.edx.keys import CourseKey
 
+from openedx.core.djangoapps.catalog.tests.factories import CourseRunFactory
+from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
 from openedx.core.djangoapps.content.course_overviews.api import (
     get_course_overview_or_none,
-    get_course_overviews
+    get_course_overviews,
+    get_course_overviews_from_ids,
+    get_pseudo_course_overview,
 )
 from openedx.core.djangoapps.content.course_overviews.tests.factories import CourseOverviewFactory
 from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase
-from ..models import CourseOverview
 
 
 class TestCourseOverviewsApi(ModuleStoreTestCase):
@@ -39,6 +43,19 @@ class TestCourseOverviewsApi(ModuleStoreTestCase):
         retrieved_course_overview = get_course_overview_or_none(course_run_key)
         assert retrieved_course_overview is None
 
+    def test_get_course_overview_from_ids(self):
+        """
+        Test for `get_course_overviews_from_ids` function.
+        """
+        course_ids = []
+        course_overview_data = CourseOverview.objects.all()
+        for course_overview in course_overview_data:
+            course_ids.append(course_overview.id)
+
+        results = get_course_overviews_from_ids(course_ids)
+
+        assert len(results) == 3
+
     def test_get_course_overviews(self):
         """
         get_course_overviews should return the expected CourseOverview data
@@ -61,3 +78,20 @@ class TestCourseOverviewsApi(ModuleStoreTestCase):
         ]
         for field in fields:
             assert field in data[0]
+
+    @patch("openedx.core.djangoapps.content.course_overviews.api.get_course_run_details")
+    def test_get_pseudo_course_overview(self, mock_get_course_run_details):
+        """
+        Test for the `get_pseudo_course_overview` function that creates a temporary course overview for courses that
+        have been deleted.
+        """
+        course_run = CourseRunFactory()
+        mock_get_course_run_details.return_value = {
+            'title': course_run['title'],
+        }
+        course_key = CourseKey.from_string(course_run['key'])
+
+        result = get_pseudo_course_overview(course_key)
+        assert result.display_name == course_run['title']
+        assert result.display_org_with_default == course_key.org
+        assert result.certificates_show_before_end