Added management command to back-populate missing audit seats

LEARNER-2876

course_discovery/apps/publisher/management/commands/add_audit_seats_to_verified_course_runs.py

+import logging
+
+from django.core.management import BaseCommand
+
+from course_discovery.apps.publisher.models import CourseRun, Seat
+
+logger = logging.getLogger(__name__)
+
+
+class Command(BaseCommand):
+    help = 'Adds audit seats to credit/verified course runs'
+
+    def add_arguments(self, parser):
+        parser.add_argument('--commit',
+                            action='store_true',
+                            dest='commit',
+                            default=False,
+                            help='Commit the new seats to the database')
+
+    def handle(self, *args, **options):
+        course_runs = CourseRun.objects.filter(seats__type__in=(Seat.CREDIT, Seat.VERIFIED,)).exclude(
+            seats__type=Seat.AUDIT)
+        if options['commit']:
+            for course_run in course_runs:
+                seat = course_run.seats.create(type=Seat.AUDIT, price=0, upgrade_deadline=None)
+                course_run_id = course_run.lms_course_id or course_run.id
+                logger.info('Created audit seat [%d] for course run [%s]', seat.id, course_run_id)
+        else:
+            logger.info('The following [%d] course runs lack audit seats...', course_runs.count())
+            for course_run in course_runs:
+                logger.info('\t%s', course_run.lms_course_id or course_run.id)

course_discovery/apps/publisher/management/commands/tests/test_add_audit_seats_to_verified_course_runs.py

+import pytest
+from django.core.management import call_command
+
+from course_discovery.apps.publisher.models import Seat
+from course_discovery.apps.publisher.tests.factories import SeatFactory
+
+
+@pytest.mark.django_db
+class TestAddAuditSeats:
+    def test_no_commit(self):
+        seats = SeatFactory.create_batch(3, type=Seat.VERIFIED)
+        call_command('add_audit_seats_to_verified_course_runs')
+        assert Seat.objects.count() == len(seats)
+
+    @pytest.mark.parametrize('seat_type', (Seat.CREDIT, Seat.VERIFIED,))
+    def test_commit(self, seat_type):
+        SeatFactory(type=Seat.AUDIT)
+        SeatFactory(type=Seat.NO_ID_PROFESSIONAL)
+        SeatFactory(type=Seat.PROFESSIONAL)
+
+        seat = SeatFactory(type=seat_type)
+        call_command('add_audit_seats_to_verified_course_runs', '--commit')
+
+        assert seat.course_run.seats.count() == 2
+        assert seat.course_run.seats.filter(type=Seat.AUDIT, price=0).exists()