Log remote NOTICE, WARNING, and similar messages using ereport().

Previously, NOTICE, WARNING, and similar messages received from remote
servers over replication, postgres_fdw, or dblink connections were printed
directly to stderr on the local server (e.g., the subscriber). As a result,
these messages lacked log prefixes (e.g., timestamp), making them harder
to trace and correlate with other log entries.

This commit addresses the issue by introducing a custom notice receiver
for replication, postgres_fdw, and dblink connections. These messages
are now logged via ereport(), ensuring they appear in the logs with proper
formatting and context, which improves clarity and aids in debugging.

Author: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CALDaNm2xsHpWRtLm-VL_HJCsaE3+1Y_n-jDEAr3-suxVqc3xoQ@mail.gmail.com

1 files changed, 7 insertions, 0 deletions

diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index 8a0b112a7ff..c459a842fa9 100644
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -240,6 +240,10 @@ dblink_get_conn(char *conname_or_str,
 					 errmsg("could not establish connection"),
 					 errdetail_internal("%s", msg)));
 		}
+
+		PQsetNoticeReceiver(conn, libpqsrv_notice_receiver,
+							gettext_noop("received message via remote connection"));
+
 		dblink_security_check(conn, NULL, connstr);
 		if (PQclientEncoding(conn) != GetDatabaseEncoding())
 			PQsetClientEncoding(conn, GetDatabaseEncodingName());
@@ -338,6 +342,9 @@ dblink_connect(PG_FUNCTION_ARGS)
 				 errdetail_internal("%s", msg)));
 	}
 
+	PQsetNoticeReceiver(conn, libpqsrv_notice_receiver,
+						gettext_noop("received message via remote connection"));
+
 	/* check password actually used if not superuser */
 	dblink_security_check(conn, connname, connstr);