From 74211d016528699205163dab8ecc7fe04aec09b2 Mon Sep 17 00:00:00 2001
From: Vigneshwaran C <vignesh21@gmail.com>
Date: Sat, 12 Mar 2022 13:04:55 +0530
Subject: [PATCH v4] Fix for invalidating logical replication relations when
 there is a change in schema.

When the schema gets changed, the rel sync cache invalidation was not
happening, fixed it by adding a callback for schema change.
---
 src/backend/replication/pgoutput/pgoutput.c |  3 +
 src/test/subscription/t/001_rep_changes.pl  | 67 +++++++++++++++++++++
 2 files changed, 70 insertions(+)

diff --git a/src/backend/replication/pgoutput/pgoutput.c b/src/backend/replication/pgoutput/pgoutput.c
index 7737242516..f68c271cf2 100644
--- a/src/backend/replication/pgoutput/pgoutput.c
+++ b/src/backend/replication/pgoutput/pgoutput.c
@@ -1936,6 +1936,9 @@ init_rel_sync_cache(MemoryContext cachectx)
 	CacheRegisterSyscacheCallback(PUBLICATIONNAMESPACEMAP,
 								  rel_sync_cache_publication_cb,
 								  (Datum) 0);
+	CacheRegisterSyscacheCallback(NAMESPACEOID,
+								  rel_sync_cache_publication_cb,
+								  (Datum) 0);
 }
 
 /*
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 91aa068c95..3e91640c03 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -542,6 +542,73 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
 
+# Test schema invalidation by renaming the schema
+# Create tables on publisher
+# Initialize publisher node
+my $node_publisher1 = PostgreSQL::Test::Cluster->new('publisher1');
+$node_publisher1->init(allows_streaming => 'logical');
+$node_publisher1->start;
+
+# Create subscriber node
+my $node_subscriber1 = PostgreSQL::Test::Cluster->new('subscriber1');
+$node_subscriber1->init(allows_streaming => 'logical');
+$node_subscriber1->start;
+
+my $publisher1_connstr = $node_publisher1->connstr . ' dbname=postgres';
+
+$node_publisher1->safe_psql('postgres', "CREATE SCHEMA sch1");
+$node_publisher1->safe_psql('postgres', "CREATE TABLE sch1.t1 (c1 int)");
+
+# Create tables on subscriber
+$node_subscriber1->safe_psql('postgres', "CREATE SCHEMA sch1");
+$node_subscriber1->safe_psql('postgres', "CREATE TABLE sch1.t1 (c1 int)");
+$node_subscriber1->safe_psql('postgres', "CREATE SCHEMA sch2");
+$node_subscriber1->safe_psql('postgres', "CREATE TABLE sch2.t1 (c1 int)");
+
+# Setup logical replication that will only be used for this test
+$node_publisher1->safe_psql('postgres',
+        "CREATE PUBLICATION tap_pub_sch FOR ALL TABLES"
+);
+$node_subscriber1->safe_psql('postgres',
+        "CREATE SUBSCRIPTION tap_sub_sch CONNECTION '$publisher1_connstr' PUBLICATION tap_pub_sch"
+);
+
+# Wait for initial table sync to finish
+$node_subscriber1->wait_for_subscription_sync($node_publisher1, 'tap_sub_sch');
+
+$node_publisher1->safe_psql('postgres',
+        "begin;
+insert into sch1.t1 values(1);
+alter schema sch1 rename to sch2;
+create schema sch1;
+create table sch1.t1(c1 int);
+insert into sch1.t1 values(2);
+insert into sch2.t1 values(3);
+commit;");
+
+$node_subscriber1->wait_for_subscription_sync($node_publisher1, 'tap_sub_sch');
+
+# Subscriber should not receive the inserted row for renamed schema
+$result =
+  $node_subscriber1->safe_psql('postgres', "SELECT * FROM sch1.t1");
+is($result, qq(1
+2), 'check rows on subscriber after schema invalidation');
+
+# Drop subscription as we don't need it anymore
+$node_subscriber1->safe_psql('postgres', "DROP SUBSCRIPTION tap_sub_sch");
+
+# Drop publications as we don't need them anymore
+$node_publisher1->safe_psql('postgres', "DROP PUBLICATION tap_pub_sch");
+
+# Clean up the tables on both publisher and subscriber as we don't need them
+$node_publisher1->safe_psql('postgres', "DROP SCHEMA sch1 cascade");
+$node_publisher1->safe_psql('postgres', "DROP SCHEMA sch2 cascade");
+$node_subscriber1->safe_psql('postgres', "DROP SCHEMA sch1 cascade");
+$node_subscriber1->safe_psql('postgres', "DROP SCHEMA sch2 cascade");
+
+$node_subscriber1->stop('fast');
+$node_publisher1->stop('fast');
+
 # CREATE PUBLICATION while wal_level=minimal should succeed, with a WARNING
 $node_publisher->append_conf(
 	'postgresql.conf', qq(
-- 
2.34.1