Fixed #21039 -- Added AddIndexConcurrently/RemoveIndexConcurrently operations for PostgreSQL.

Thanks to Simon Charettes for review.

Co-Authored-By: Daniel Tao <daniel.tao@gmail.com>

tests/postgres_tests/test_operations.py

@@ -0,0 +1,144 @@
+import unittest
+
+from migrations.test_base import OperationTestBase
+
+from django.db import connection, models
+from django.db.models import Index
+from django.db.utils import NotSupportedError
+from django.test import modify_settings
+
+try:
+    from django.contrib.postgres.operations import (
+        AddIndexConcurrently, RemoveIndexConcurrently,
+    )
+    from django.contrib.postgres.indexes import BrinIndex, BTreeIndex
+except ImportError:
+    pass
+
+
+@unittest.skipUnless(connection.vendor == 'postgresql', 'PostgreSQL specific tests.')
+@modify_settings(INSTALLED_APPS={'append': 'migrations'})
+class AddIndexConcurrentlyTests(OperationTestBase):
+    app_label = 'test_add_concurrently'
+
+    def test_requires_atomic_false(self):
+        project_state = self.set_up_test_model(self.app_label)
+        new_state = project_state.clone()
+        operation = AddIndexConcurrently(
+            'Pony',
+            models.Index(fields=['pink'], name='pony_pink_idx'),
+        )
+        msg = (
+            'The AddIndexConcurrently operation cannot be executed inside '
+            'a transaction (set atomic = False on the migration).'
+        )
+        with self.assertRaisesMessage(NotSupportedError, msg):
+            with connection.schema_editor(atomic=True) as editor:
+                operation.database_forwards(self.app_label, editor, project_state, new_state)
+
+    def test_add(self):
+        project_state = self.set_up_test_model(self.app_label, index=False)
+        table_name = '%s_pony' % self.app_label
+        index = Index(fields=['pink'], name='pony_pink_idx')
+        new_state = project_state.clone()
+        operation = AddIndexConcurrently('Pony', index)
+        self.assertEqual(
+            operation.describe(),
+            'Concurrently create index pony_pink_idx on field(s) pink of '
+            'model Pony'
+        )
+        operation.state_forwards(self.app_label, new_state)
+        self.assertEqual(len(new_state.models[self.app_label, 'pony'].options['indexes']), 1)
+        self.assertIndexNotExists(table_name, ['pink'])
+        # Add index.
+        with connection.schema_editor(atomic=False) as editor:
+            operation.database_forwards(self.app_label, editor, project_state, new_state)
+        self.assertIndexExists(table_name, ['pink'])
+        # Reversal.
+        with connection.schema_editor(atomic=False) as editor:
+            operation.database_backwards(self.app_label, editor, new_state, project_state)
+        self.assertIndexNotExists(table_name, ['pink'])
+        # Deconstruction.
+        name, args, kwargs = operation.deconstruct()
+        self.assertEqual(name, 'AddIndexConcurrently')
+        self.assertEqual(args, [])
+        self.assertEqual(kwargs, {'model_name': 'Pony', 'index': index})
+
+    def test_add_other_index_type(self):
+        project_state = self.set_up_test_model(self.app_label, index=False)
+        table_name = '%s_pony' % self.app_label
+        new_state = project_state.clone()
+        operation = AddIndexConcurrently(
+            'Pony',
+            BrinIndex(fields=['pink'], name='pony_pink_brin_idx'),
+        )
+        self.assertIndexNotExists(table_name, ['pink'])
+        # Add index.
+        with connection.schema_editor(atomic=False) as editor:
+            operation.database_forwards(self.app_label, editor, project_state, new_state)
+        self.assertIndexExists(table_name, ['pink'], index_type='brin')
+        # Reversal.
+        with connection.schema_editor(atomic=False) as editor:
+            operation.database_backwards(self.app_label, editor, new_state, project_state)
+        self.assertIndexNotExists(table_name, ['pink'])
+
+    def test_add_with_options(self):
+        project_state = self.set_up_test_model(self.app_label, index=False)
+        table_name = '%s_pony' % self.app_label
+        new_state = project_state.clone()
+        index = BTreeIndex(fields=['pink'], name='pony_pink_btree_idx', fillfactor=70)
+        operation = AddIndexConcurrently('Pony', index)
+        self.assertIndexNotExists(table_name, ['pink'])
+        # Add index.
+        with connection.schema_editor(atomic=False) as editor:
+            operation.database_forwards(self.app_label, editor, project_state, new_state)
+        self.assertIndexExists(table_name, ['pink'], index_type='btree')
+        # Reversal.
+        with connection.schema_editor(atomic=False) as editor:
+            operation.database_backwards(self.app_label, editor, new_state, project_state)
+        self.assertIndexNotExists(table_name, ['pink'])
+
+
+@unittest.skipUnless(connection.vendor == 'postgresql', 'PostgreSQL specific tests.')
+@modify_settings(INSTALLED_APPS={'append': 'migrations'})
+class RemoveIndexConcurrentlyTests(OperationTestBase):
+    app_label = 'test_rm_concurrently'
+
+    def test_requires_atomic_false(self):
+        project_state = self.set_up_test_model(self.app_label, index=True)
+        new_state = project_state.clone()
+        operation = RemoveIndexConcurrently('Pony', 'pony_pink_idx')
+        msg = (
+            'The RemoveIndexConcurrently operation cannot be executed inside '
+            'a transaction (set atomic = False on the migration).'
+        )
+        with self.assertRaisesMessage(NotSupportedError, msg):
+            with connection.schema_editor(atomic=True) as editor:
+                operation.database_forwards(self.app_label, editor, project_state, new_state)
+
+    def test_remove(self):
+        project_state = self.set_up_test_model(self.app_label, index=True)
+        table_name = '%s_pony' % self.app_label
+        self.assertTableExists(table_name)
+        new_state = project_state.clone()
+        operation = RemoveIndexConcurrently('Pony', 'pony_pink_idx')
+        self.assertEqual(
+            operation.describe(),
+            'Concurrently remove index pony_pink_idx from Pony',
+        )
+        operation.state_forwards(self.app_label, new_state)
+        self.assertEqual(len(new_state.models[self.app_label, 'pony'].options['indexes']), 0)
+        self.assertIndexExists(table_name, ['pink'])
+        # Remove index.
+        with connection.schema_editor(atomic=False) as editor:
+            operation.database_forwards(self.app_label, editor, project_state, new_state)
+        self.assertIndexNotExists(table_name, ['pink'])
+        # Reversal.
+        with connection.schema_editor(atomic=False) as editor:
+            operation.database_backwards(self.app_label, editor, new_state, project_state)
+        self.assertIndexExists(table_name, ['pink'])
+        # Deconstruction.
+        name, args, kwargs = operation.deconstruct()
+        self.assertEqual(name, 'RemoveIndexConcurrently')
+        self.assertEqual(args, [])
+        self.assertEqual(kwargs, {'model_name': 'Pony', 'name': 'pony_pink_idx'})