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 

diff --git a/doc/src/sgml/ref/pg_ctl-ref.sgml b/doc/src/sgml/ref/pg_ctl-ref.sgml
index 6ceb7816dc87b06a43e84a81ae0e08b69cbe9b03..a00c355f4aac5591f9d3d38ede7d265ce65b95b9 100644 (file)
--- a/doc/src/sgml/ref/pg_ctl-ref.sgml
+++ b/doc/src/sgml/ref/pg_ctl-ref.sgml
@@ -91,6 +91,8 @@ PostgreSQL documentation
   
    pg_ctl
    promote
+   -w
+   -t seconds
    -s
    -D datadir
   
@@ -361,8 +363,8 @@ PostgreSQL documentation
       --timeout
       
        
-        The maximum number of seconds to wait when waiting for startup or
-        shutdown to complete.  Defaults to the value of the
+        The maximum number of seconds to wait when waiting for an operation
+        to complete (see option -w). Defaults to the value of the
         PGCTLTIMEOUT environment variable or, if not set, to 60
         seconds.
        
@@ -383,8 +385,23 @@ PostgreSQL documentation
       -w
       
        
-        Wait for the startup or shutdown to complete.
-        Waiting is the default option for shutdowns, but not startups.
+        Wait for an operation to complete.  This is supported for the
+        modes start, stop,
+        restart, promote,
+        and register.
+       
+
+       
+        Waiting is the default option for shutdowns, but not startups,
+        restarts, or promotions.  This is mainly for historical reasons; the
+        waiting option is almost always preferable.  If waiting is not
+        selected, the requested action is triggered, but there is no feedback
+        about its success.  In that case, the server log file or an external
+        monitoring system would have to be used to check the progress and
+        success of the operation.
+       
+
+       
         When waiting for startup, pg_ctl repeatedly
         attempts to connect to the server.
         When waiting for shutdown, pg_ctl waits for
@@ -400,8 +417,8 @@ PostgreSQL documentation
       -W
       
        
-        Do not wait for startup or shutdown to complete.  This is the
-        default for start and restart modes.
+        Do not wait for an operation to complete.  This is the opposite of the
+        option -w.
        
       
      

diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
index eb8a67a9033e9d2fc65b186ab6be8a5ad402f195..2f0976a9cc155d21e28c32706ecc1669ed35506c 100644 (file)
--- 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 1461234f2af8824bed1c33a090da97241848fba2..0b6090b6eb515e17ce434eefb7f63241995e9681 100644 (file)
--- 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');