v2-0002-add-different-dry-run-logging-for-pg_createsubscr.patch

From 3329e2269ba9a336f17a8a6ad9caf3a57515fdb7 Mon Sep 17 00:00:00 2001
From: Peter Smith <peter.b.smith@fujitsu.com>
Date: Thu, 9 Oct 2025 11:40:44 +1100
Subject: [PATCH v2] add different dry-run logging for pg_createsubscriber

---
 src/bin/pg_basebackup/pg_createsubscriber.c        | 89 +++++++++++++++-------
 src/bin/pg_basebackup/t/040_pg_createsubscriber.pl |  6 +-
 2 files changed, 65 insertions(+), 30 deletions(-)

diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 2e8972e..b23c1cd 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -679,13 +679,20 @@ modify_subscriber_sysid(const struct CreateSubscriberOptions *opt)
 	cf->system_identifier |= ((uint64) tv.tv_usec) << 12;
 	cf->system_identifier |= getpid() & 0xFFF;
 
-	if (!dry_run)
+	if (dry_run)
+		pg_log_info("in dry-run mode, otherwise system identifier would be %" PRIu64 " on subscriber",
+					cf->system_identifier);
+	else
+	{
 		update_controlfile(subscriber_dir, cf, true);
+		pg_log_info("system identifier is %" PRIu64 " on subscriber",
+					cf->system_identifier);
+	}
 
-	pg_log_info("system identifier is %" PRIu64 " on subscriber",
-				cf->system_identifier);
-
-	pg_log_info("running pg_resetwal on the subscriber");
+	if (dry_run)
+		pg_log_info("in dry-run mode, otherwise would run pg_resetwal on the subscriber");
+	else
+		pg_log_info("running pg_resetwal on the subscriber");
 
 	cmd_str = psprintf("\"%s\" -D \"%s\" > \"%s\"", pg_resetwal_path,
 					   subscriber_dir, DEVNULL);
@@ -801,10 +808,7 @@ setup_publisher(struct LogicalRepInfo *dbinfo)
 		if (lsn)
 			pg_free(lsn);
 		lsn = create_logical_replication_slot(conn, &dbinfo[i]);
-		if (lsn != NULL || dry_run)
-			pg_log_info("create replication slot \"%s\" on publisher",
-						dbinfo[i].replslotname);
-		else
+		if (lsn == NULL && !dry_run)
 			exit(1);
 
 		/*
@@ -1124,11 +1128,14 @@ drop_existing_subscriptions(PGconn *conn, const char *subname, const char *dbnam
 					  subname);
 	appendPQExpBuffer(query, " DROP SUBSCRIPTION %s;", subname);
 
-	pg_log_info("dropping subscription \"%s\" in database \"%s\"",
-				subname, dbname);
-
-	if (!dry_run)
+	if (dry_run)
+		pg_log_info("in dry-run mode, otherwise would drop subscription \"%s\" in database \"%s\"",
+					subname, dbname);
+	else
 	{
+		pg_log_info("dropping subscription \"%s\" in database \"%s\"",
+					subname, dbname);
+
 		res = PQexec(conn, query->data);
 
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
@@ -1375,8 +1382,12 @@ create_logical_replication_slot(PGconn *conn, struct LogicalRepInfo *dbinfo)
 
 	Assert(conn != NULL);
 
-	pg_log_info("creating the replication slot \"%s\" in database \"%s\"",
-				slot_name, dbinfo->dbname);
+	if (dry_run)
+		pg_log_info("in dry-run mode, otherwise would create the replication slot \"%s\" in database \"%s\"",
+					slot_name, dbinfo->dbname);
+	else
+		pg_log_info("creating the replication slot \"%s\" in database \"%s\"",
+					slot_name, dbinfo->dbname);
 
 	slot_name_esc = PQescapeLiteral(conn, slot_name, strlen(slot_name));
 
@@ -1424,8 +1435,12 @@ drop_replication_slot(PGconn *conn, struct LogicalRepInfo *dbinfo,
 
 	Assert(conn != NULL);
 
-	pg_log_info("dropping the replication slot \"%s\" in database \"%s\"",
-				slot_name, dbinfo->dbname);
+	if (dry_run)
+		pg_log_info("in dry-run mode, otherwise would drop the replication slot \"%s\" in database \"%s\"",
+					slot_name, dbinfo->dbname);
+	else
+		pg_log_info("dropping the replication slot \"%s\" in database \"%s\"",
+					slot_name, dbinfo->dbname);
 
 	slot_name_esc = PQescapeLiteral(conn, slot_name, strlen(slot_name));
 
@@ -1651,8 +1666,12 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	PQclear(res);
 	resetPQExpBuffer(str);
 
-	pg_log_info("creating publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+	if (dry_run)
+		pg_log_info("in dry-run mode, otherwise would create publication \"%s\" in database \"%s\"",
+					dbinfo->pubname, dbinfo->dbname);
+	else
+		pg_log_info("creating publication \"%s\" in database \"%s\"",
+					dbinfo->pubname, dbinfo->dbname);
 
 	appendPQExpBuffer(str, "CREATE PUBLICATION %s FOR ALL TABLES",
 					  ipubname_esc);
@@ -1694,8 +1713,12 @@ drop_publication(PGconn *conn, const char *pubname, const char *dbname,
 
 	pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				pubname, dbname);
+	if (dry_run)
+		pg_log_info("in dry-run mode, otherwise would drop publication \"%s\" in database \"%s\"",
+					pubname, dbname);
+	else
+		pg_log_info("dropping publication \"%s\" in database \"%s\"",
+					pubname, dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
@@ -1803,8 +1826,12 @@ create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo)
 	pubconninfo_esc = PQescapeLiteral(conn, dbinfo->pubconninfo, strlen(dbinfo->pubconninfo));
 	replslotname_esc = PQescapeLiteral(conn, dbinfo->replslotname, strlen(dbinfo->replslotname));
 
-	pg_log_info("creating subscription \"%s\" in database \"%s\"",
-				dbinfo->subname, dbinfo->dbname);
+	if (dry_run)
+		pg_log_info("in dry-run mode, otherwise would create subscription \"%s\" in database \"%s\"",
+					dbinfo->subname, dbinfo->dbname);
+	else
+		pg_log_info("creating subscription \"%s\" in database \"%s\"",
+					dbinfo->subname, dbinfo->dbname);
 
 	appendPQExpBuffer(str,
 					  "CREATE SUBSCRIPTION %s CONNECTION %s PUBLICATION %s "
@@ -1901,8 +1928,12 @@ set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo, cons
 	 */
 	originname = psprintf("pg_%u", suboid);
 
-	pg_log_info("setting the replication progress (node name \"%s\", LSN %s) in database \"%s\"",
-				originname, lsnstr, dbinfo->dbname);
+	if (dry_run)
+		pg_log_info("in dry-run mode, otherwise, would set the replication progress (node name \"%s\", LSN %s) in database \"%s\"",
+					originname, lsnstr, dbinfo->dbname);
+	else
+		pg_log_info("setting the replication progress (node name \"%s\", LSN %s) in database \"%s\"",
+					originname, lsnstr, dbinfo->dbname);
 
 	resetPQExpBuffer(str);
 	appendPQExpBuffer(str,
@@ -1947,8 +1978,12 @@ enable_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo)
 
 	subname = PQescapeIdentifier(conn, dbinfo->subname, strlen(dbinfo->subname));
 
-	pg_log_info("enabling subscription \"%s\" in database \"%s\"",
-				dbinfo->subname, dbinfo->dbname);
+	if (dry_run)
+		pg_log_info("in dry-run mode, otherwise would enable subscription \"%s\" in database \"%s\"",
+					dbinfo->subname, dbinfo->dbname);
+	else
+		pg_log_info("enabling subscription \"%s\" in database \"%s\"",
+					dbinfo->subname, dbinfo->dbname);
 
 	appendPQExpBuffer(str, "ALTER SUBSCRIPTION %s ENABLE", subname);
 
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index 229fef5..60a8f8c 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -436,11 +436,11 @@ my ($stdout, $stderr) = run_command(
 
 # Verify that the required logical replication objects are output.
 # The expected count 3 refers to postgres, $db1 and $db2 databases.
-is(scalar(() = $stderr =~ /creating publication/g),
+is(scalar(() = $stderr =~ /would create publication/g),
 	3, "verify publications are created for all databases");
-is(scalar(() = $stderr =~ /creating the replication slot/g),
+is(scalar(() = $stderr =~ /would create the replication slot/g),
 	3, "verify replication slots are created for all databases");
-is(scalar(() = $stderr =~ /creating subscription/g),
+is(scalar(() = $stderr =~ /would create subscription/g),
 	3, "verify subscriptions are created for all databases");
 
 # Run pg_createsubscriber on node S.  --verbose is used twice
-- 
1.8.3.1