From 94c49d53402240ad7ddbcae9049ff2840a54b9c6 Mon Sep 17 00:00:00 2001 From: Fujii Masao Date: Fri, 18 Feb 2022 11:38:12 +0900 Subject: [PATCH] postgres_fdw: Make postgres_fdw.application_name support more escape sequences. Commit 6e0cb3dec1 allowed postgres_fdw.application_name to include escape sequences %a (application name), %d (database name), %u (user name) and %p (pid). In addition to them, this commit makes it support the escape sequences for session ID (%c) and cluster name (%C). These are helpful to investigate where each remote transactions came from. Author: Fujii Masao Reviewed-by: Ryohei Takahashi, Kyotaro Horiguchi Discussion: https://postgr.es/m/1041dc9a-c976-049f-9f14-e7d94c29c4b2@oss.nttdata.com --- .../postgres_fdw/expected/postgres_fdw.out | 20 +++++++++++++++++++ contrib/postgres_fdw/option.c | 6 ++++++ contrib/postgres_fdw/sql/postgres_fdw.sql | 11 ++++++++++ doc/src/sgml/postgres-fdw.sgml | 14 +++++++++++++ src/include/utils/guc.h | 2 +- 5 files changed, 52 insertions(+), 1 deletion(-) diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index b2e02caefe..057342083c 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -10910,6 +10910,26 @@ SELECT pg_terminate_backend(pid, 180000) FROM pg_stat_activity t (1 row) +-- Test %c (session ID) and %C (cluster name) escape sequences. +SET postgres_fdw.application_name TO 'fdw_%C%c'; +SELECT 1 FROM ft6 LIMIT 1; + ?column? +---------- + 1 +(1 row) + +SELECT pg_terminate_backend(pid, 180000) FROM pg_stat_activity + WHERE application_name = + substring('fdw_' || current_setting('cluster_name') || + to_hex(trunc(EXTRACT(EPOCH FROM (SELECT backend_start FROM + pg_stat_get_activity(pg_backend_pid()))))::integer) || '.' || + to_hex(pg_backend_pid()) + for current_setting('max_identifier_length')::int); + pg_terminate_backend +---------------------- + t +(1 row) + --Clean up RESET postgres_fdw.application_name; RESET debug_discard_caches; diff --git a/contrib/postgres_fdw/option.c b/contrib/postgres_fdw/option.c index fc3ce6a53a..af38e956e7 100644 --- a/contrib/postgres_fdw/option.c +++ b/contrib/postgres_fdw/option.c @@ -489,6 +489,12 @@ process_pgfdw_appname(const char *appname) case 'a': appendStringInfoString(&buf, application_name); break; + case 'c': + appendStringInfo(&buf, "%lx.%x", (long) (MyStartTime), MyProcPid); + break; + case 'C': + appendStringInfoString(&buf, cluster_name); + break; case 'd': appendStringInfoString(&buf, MyProcPort->database_name); break; diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index e050639b57..6c9f579c41 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -3501,6 +3501,17 @@ SELECT pg_terminate_backend(pid, 180000) FROM pg_stat_activity substring('fdw_' || current_setting('application_name') || CURRENT_USER || '%' for current_setting('max_identifier_length')::int); +-- Test %c (session ID) and %C (cluster name) escape sequences. +SET postgres_fdw.application_name TO 'fdw_%C%c'; +SELECT 1 FROM ft6 LIMIT 1; +SELECT pg_terminate_backend(pid, 180000) FROM pg_stat_activity + WHERE application_name = + substring('fdw_' || current_setting('cluster_name') || + to_hex(trunc(EXTRACT(EPOCH FROM (SELECT backend_start FROM + pg_stat_get_activity(pg_backend_pid()))))::integer) || '.' || + to_hex(pg_backend_pid()) + for current_setting('max_identifier_length')::int); + --Clean up RESET postgres_fdw.application_name; RESET debug_discard_caches; diff --git a/doc/src/sgml/postgres-fdw.sgml b/doc/src/sgml/postgres-fdw.sgml index 7bb6e525a4..dc57fe4b0d 100644 --- a/doc/src/sgml/postgres-fdw.sgml +++ b/doc/src/sgml/postgres-fdw.sgml @@ -984,6 +984,20 @@ postgres=# SELECT postgres_fdw_disconnect_all(); %a Application name on local server + + %c + + Session ID on local server + (see for details) + + + + %C + + Cluster name in local server + (see for details) + + %u User name on local server diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h index 6bb81707b0..f1bfe79feb 100644 --- a/src/include/utils/guc.h +++ b/src/include/utils/guc.h @@ -271,7 +271,7 @@ extern int temp_file_limit; extern int num_temp_buffers; -extern char *cluster_name; +extern PGDLLIMPORT char *cluster_name; extern PGDLLIMPORT char *ConfigFileName; extern char *HbaFileName; extern char *IdentFileName;