From 6e0cb3dec10e460288d68a128e3d79d16a230cdb Mon Sep 17 00:00:00 2001 From: Fujii Masao Date: Fri, 24 Dec 2021 16:55:11 +0900 Subject: postgres_fdw: Allow postgres_fdw.application_name to include escape sequences. application_name that used when postgres_fdw establishes a connection to a foreign server can be specified in either or both a connection parameter of a server object and GUC postgres_fdw.application_name. This commit allows those parameters to include escape sequences that begins with % character. Then postgres_fdw replaces those escape sequences with status information. For example, %d and %u are replaced with user name and database name in local server, respectively. This feature enables us to add information more easily to track remote transactions or queries, into application_name of a remote connection. Author: Hayato Kuroda Reviewed-by: Kyotaro Horiguchi, Masahiro Ikeda, Hou Zhijie, Fujii Masao Discussion: https://postgr.es/m/TYAPR01MB5866FAE71C66547C64616584F5EB9@TYAPR01MB5866.jpnprd01.prod.outlook.com Discussion: https://postgr.es/m/TYCPR01MB5870D1E8B949DAF6D3B84E02F5F29@TYCPR01MB5870.jpnprd01.prod.outlook.com --- contrib/postgres_fdw/sql/postgres_fdw.sql | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'contrib/postgres_fdw/sql/postgres_fdw.sql') diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index beeac8af1ed..105b133bbd1 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -3452,3 +3452,24 @@ CREATE FOREIGN TABLE inv_bsz (c1 int ) -- No option is allowed to be specified at foreign data wrapper level ALTER FOREIGN DATA WRAPPER postgres_fdw OPTIONS (nonexistent 'fdw'); + +-- =================================================================== +-- test postgres_fdw.application_name GUC +-- =================================================================== +-- Close all the existing cached connections so that new connection +-- will be established with new setting of postgres_fdw.application_name. +SELECT 1 FROM postgres_fdw_disconnect_all(); + +-- Add some escape sequences into postgres_fdw.application_name +-- so as to test that they are replaced with status information expectedly. +SET postgres_fdw.application_name TO '%a%u%d%p%%'; + +BEGIN; +SELECT 1 FROM ft6 LIMIT 1; +SELECT count(*) FROM pg_stat_activity + WHERE application_name = current_setting('application_name') || + CURRENT_USER || current_database() || pg_backend_pid() || '%'; +COMMIT; + +--Clean up +RESET postgres_fdw.application_name; -- cgit v1.2.3