add expiration_date indexes concurrently

Author: aaxelb

trove/migrations/0008_expiration_dates.py

@@ -25,12 +25,4 @@ class Migration(migrations.Migration):
             name='expiration_date',
             field=models.DateField(blank=True, help_text='An (optional) date when this description will no longer be valid.', null=True),
         ),
-        migrations.AddIndex(
-            model_name='latestindexcardrdf',
-            index=models.Index(fields=['expiration_date'], name='trove_lates_expirat_92ac89_idx'),
-        ),
-        migrations.AddIndex(
-            model_name='supplementaryindexcardrdf',
-            index=models.Index(fields=['expiration_date'], name='trove_suppl_expirat_3ea6e1_idx'),
-        ),
     ]

trove/migrations/0009_expiration_date_indexes.py

@@ -0,0 +1,21 @@
+from django.db import migrations, models
+from django.contrib.postgres.operations import AddIndexConcurrently
+
+
+class Migration(migrations.Migration):
+    atomic = False  # allow adding indexes concurrently (without locking tables)
+
+    dependencies = [
+        ('trove', '0008_expiration_dates'),
+    ]
+
+    operations = [
+        AddIndexConcurrently(
+            model_name='latestindexcardrdf',
+            index=models.Index(fields=['expiration_date'], name='trove_lates_expirat_92ac89_idx'),
+        ),
+        AddIndexConcurrently(
+            model_name='supplementaryindexcardrdf',
+            index=models.Index(fields=['expiration_date'], name='trove_suppl_expirat_3ea6e1_idx'),
+        ),
+    ]