From 112faf1378ee62db75cd9e3223c86bf53b8c2736 Mon Sep 17 00:00:00 2001 From: Fujii Masao Date: Tue, 22 Jul 2025 14:16:45 +0900 Subject: [PATCH] Log remote NOTICE, WARNING, and similar messages using ereport(). MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Reviewed-by: Álvaro Herrera Reviewed-by: Fujii Masao Discussion: https://postgr.es/m/CALDaNm2xsHpWRtLm-VL_HJCsaE3+1Y_n-jDEAr3-suxVqc3xoQ@mail.gmail.com --- contrib/dblink/dblink.c | 7 +++++ contrib/postgres_fdw/connection.c | 3 ++ .../libpqwalreceiver/libpqwalreceiver.c | 3 ++ src/include/libpq/libpq-be-fe-helpers.h | 30 +++++++++++++++++++ 4 files changed, 43 insertions(+) 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); diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 304f3c20f83..e41d47c3bbd 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -625,6 +625,9 @@ connect_pg_server(ForeignServer *server, UserMapping *user) server->servername), errdetail_internal("%s", pchomp(PQerrorMessage(conn))))); + PQsetNoticeReceiver(conn, libpqsrv_notice_receiver, + gettext_noop("received message via remote connection")); + /* Perform post-connection security checks. */ pgfdw_security_check(keywords, values, user, conn); diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c index f7b5d093681..0c75fe064d5 100644 --- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c +++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c @@ -232,6 +232,9 @@ libpqrcv_connect(const char *conninfo, bool replication, bool logical, errhint("Target server's authentication method must be changed, or set password_required=false in the subscription parameters."))); } + PQsetNoticeReceiver(conn->streamConn, libpqsrv_notice_receiver, + gettext_noop("received message via replication")); + /* * Set always-secure search path for the cases where the connection is * used to run SQL queries, so malicious users can't get control. diff --git a/src/include/libpq/libpq-be-fe-helpers.h b/src/include/libpq/libpq-be-fe-helpers.h index 16205b824fa..49137a0a570 100644 --- a/src/include/libpq/libpq-be-fe-helpers.h +++ b/src/include/libpq/libpq-be-fe-helpers.h @@ -454,4 +454,34 @@ exit: ; return error; } +/* + * libpqsrv_notice_receiver + * + * Custom notice receiver for libpq connections. + * + * This function is intended to be set via PQsetNoticeReceiver() so that + * NOTICE, WARNING, and similar messages from the connection are reported via + * ereport(), instead of being printed to stderr. + */ +static inline void +libpqsrv_notice_receiver(void *arg, const PGresult *res) +{ + char *message; + int len; + char *prefix = (char *) arg; + + /* + * Trim the trailing newline from the message text returned from + * PQresultErrorMessage(), as it always includes one, to produce cleaner + * log output. + */ + message = PQresultErrorMessage(res); + len = strlen(message); + if (len > 0 && message[len - 1] == '\n') + len--; + + ereport(LOG, + errmsg_internal("%s: %.*s", _(prefix), len, message)); +} + #endif /* LIBPQ_BE_FE_HELPERS_H */