Bug 1842924 - Update deletion constraints for performancedatumreplica…

…te. (#7744)

tests/model/cycle_data/test_perfherder_cycling.py

@@ -20,6 +20,7 @@
 from treeherder.perf.exceptions import MaxRuntimeExceeded
 from treeherder.perf.models import (
     PerformanceDatum,
+    PerformanceDatumReplicate,
     PerformanceSignature,
     PerformanceAlertSummary,
     PerformanceAlert,
@@ -823,6 +824,29 @@ def test_deleting_performance_data_cascades_to_perf_multicomit_data(test_perf_da
     assert MultiCommitDatum.objects.count() == 0
 
 
+def test_deleting_performance_data_cascades_to_perf_datum_replicate(test_perf_data):
+    perf_datum = test_perf_data[0]
+    PerformanceDatumReplicate.objects.create(performance_datum=perf_datum, value=0.0)
+
+    assert PerformanceDatumReplicate.objects.count() == 1
+
+    try:
+        cursor = connection.cursor()
+        cursor.execute(
+            '''
+            DELETE FROM `performance_datum`
+            WHERE id = %s
+            ''',
+            [perf_datum.id],
+        )
+    except IntegrityError:
+        pytest.fail()
+    finally:
+        cursor.close()
+
+    assert PerformanceDatumReplicate.objects.count() == 0
+
+
 def test_alerts_older_than_a_year_are_removed_even_if_signature_is_active(test_perf_alert):
     # alert (fixture) comes pre linked to an active signature
     test_perf_alert.created = datetime.now() - timedelta(days=365)

treeherder/perf/migrations/0050_cascade_perf_datum_deletion_replicate.py

@@ -0,0 +1,34 @@
+# Generated by Django 3.0.8 on 2020-12-11 14:42
+
+from django.db import migrations
+
+DATUM_REPLICATE_CONSTRAINT_SYMBOL = (
+    'performance_datum_re_performance_datum_id_fe2ed518_fk_performan'
+)
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('perf', '0049_performancedatumreplicate'),
+    ]
+
+    operations = [
+        migrations.RunSQL(
+            # add ON DELETE CASCADE at database level
+            [
+                f'ALTER TABLE performance_datum_replicate '
+                f'DROP FOREIGN KEY {DATUM_REPLICATE_CONSTRAINT_SYMBOL};',
+                f'ALTER TABLE performance_datum_replicate '
+                f'ADD CONSTRAINT {DATUM_REPLICATE_CONSTRAINT_SYMBOL} '
+                f'FOREIGN KEY (performance_datum_id) REFERENCES performance_datum (ID) ON DELETE CASCADE;',
+            ],
+            # put back the non-CASCADE foreign key constraint
+            reverse_sql=[
+                f'ALTER TABLE performance_datum_replicate '
+                f'DROP FOREIGN KEY {DATUM_REPLICATE_CONSTRAINT_SYMBOL};',
+                f'ALTER TABLE performance_datum_replicate '
+                f'ADD CONSTRAINT {DATUM_REPLICATE_CONSTRAINT_SYMBOL} '
+                f'FOREIGN KEY (performance_datum_id) REFERENCES performance_datum (ID);',
+            ],
+        )
+    ]