pg_ctl: Add wait option to promote action

When waiting is selected for the promote action, look into pg_control
until the state changes, then use the PQping-based waiting until the
server is reachable.

Reviewed-by: Michael Paquier <michael.paquier@gmail.com>

2 files changed, 49 insertions, 14 deletions

diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
index eb8a67a9033..2f0976a9cc1 100644
--- a/src/bin/pg_ctl/pg_ctl.c
+++ b/src/bin/pg_ctl/pg_ctl.c
@@ -1228,7 +1228,34 @@ do_promote(void)
 		exit(1);
 	}
 
-	print_msg(_("server promoting\n"));
+	if (do_wait)
+	{
+		DBState state = DB_STARTUP;
+
+		print_msg(_("waiting for server to promote..."));
+		while (wait_seconds > 0)
+		{
+			state = get_control_dbstate();
+			if (state == DB_IN_PRODUCTION)
+				break;
+
+			print_msg(".");
+			pg_usleep(1000000);     /* 1 sec */
+			wait_seconds--;
+		}
+		if (state == DB_IN_PRODUCTION)
+		{
+			print_msg(_(" done\n"));
+			print_msg(_("server promoted\n"));
+		}
+		else
+		{
+			print_msg(_(" stopped waiting\n"));
+			print_msg(_("server is still promoting\n"));
+		}
+	}
+	else
+		print_msg(_("server promoting\n"));
 }
 
 
@@ -2405,18 +2432,10 @@ main(int argc, char **argv)
 
 	if (!wait_set)
 	{
-		switch (ctl_command)
-		{
-			case RESTART_COMMAND:
-			case START_COMMAND:
-				do_wait = false;
-				break;
-			case STOP_COMMAND:
-				do_wait = true;
-				break;
-			default:
-				break;
-		}
+		if (ctl_command == STOP_COMMAND)
+			do_wait = true;
+		else
+			do_wait = false;
 	}
 
 	if (ctl_command == RELOAD_COMMAND)
diff --git a/src/bin/pg_ctl/t/003_promote.pl b/src/bin/pg_ctl/t/003_promote.pl
index 1461234f2af..0b6090b6eb5 100644
--- a/src/bin/pg_ctl/t/003_promote.pl
+++ b/src/bin/pg_ctl/t/003_promote.pl
@@ -3,7 +3,7 @@ use warnings;
 
 use PostgresNode;
 use TestLib;
-use Test::More tests => 9;
+use Test::More tests => 12;
 
 my $tempdir = TestLib::tempdir;
 
@@ -37,3 +37,19 @@ command_ok([ 'pg_ctl', '-D', $node_standby->data_dir, 'promote' ],
 
 ok($node_standby->poll_query_until('postgres', 'SELECT NOT pg_is_in_recovery()'),
    'promoted standby is not in recovery');
+
+# same again with wait option
+$node_standby = get_new_node('standby2');
+$node_standby->init_from_backup($node_primary, 'my_backup', has_streaming => 1);
+$node_standby->start;
+
+is($node_standby->safe_psql('postgres', 'SELECT pg_is_in_recovery()'),
+   't', 'standby is in recovery');
+
+command_ok([ 'pg_ctl', '-D', $node_standby->data_dir, '-w', 'promote' ],
+		   'pg_ctl -w promote of standby runs');
+
+# no wait here
+
+is($node_standby->safe_psql('postgres', 'SELECT pg_is_in_recovery()'),
+   'f', 'promoted standby is not in recovery');