Hi,
On Wed, 7 Apr 2021 20:07:41 +0200
Jehan-Guillaume de Rorthais <j...@dalibo.com> wrote:
[...]
> > > Let me know if it worth that I work on an official patch.
> >
> > Let's give it a try ...
>
> OK
So, as promised, here is my take to port my previous work on PostgreSQL
source tree.
Make check pass with no errors. The new class probably deserve some own TAP
tests.
Note that I added a PostgresVersion class for easier and cleaner version
comparisons. This could be an interesting take away no matter what.
I still have some more ideas to cleanup, revamp and extend the base class, but
I prefer to go incremental to keep things review-ability.
Thanks,
>From 077e447995b3b8bb4c0594a6616e1350acd9d48b Mon Sep 17 00:00:00 2001
From: Jehan-Guillaume de Rorthais <j...@dalibo.com>
Date: Mon, 12 Apr 2021 14:45:17 +0200
Subject: [PATCH] Draft: Makes PostgresNode multi-version aware
---
src/test/perl/PostgresNode.pm | 708 ++++++++++++++++++++++++++++---
src/test/perl/PostgresVersion.pm | 65 +++
2 files changed, 704 insertions(+), 69 deletions(-)
create mode 100644 src/test/perl/PostgresVersion.pm
diff --git a/src/test/perl/PostgresNode.pm b/src/test/perl/PostgresNode.pm
index e26b2b3f30..d7a9e54efd 100644
--- a/src/test/perl/PostgresNode.pm
+++ b/src/test/perl/PostgresNode.pm
@@ -102,6 +102,7 @@ use Test::More;
use TestLib ();
use Time::HiRes qw(usleep);
use Scalar::Util qw(blessed);
+use PostgresVersion;
our @EXPORT = qw(
get_new_node
@@ -376,9 +377,42 @@ sub dump_info
return;
}
+# Internal routine to allows streaming replication on a primary node.
+sub allows_streaming
+{
+ my ($self, $allows_streaming) = @_;
+ my $pgdata = $self->data_dir;
+ my $wal_level;
+
+ if ($allows_streaming eq "logical")
+ {
+ $wal_level = "logical";
+ }
+ else
+ {
+ $wal_level = "replica";
+ }
+
+ $self->append_conf( 'postgresql.conf', qq{
+ wal_level = $wal_level
+ max_wal_senders = 10
+ max_replication_slots = 10
+ wal_log_hints = on
+ hot_standby = on
+ # conservative settings to ensure we can run multiple postmasters:
+ shared_buffers = 1MB
+ max_connections = 10
+ # limit disk space consumption, too:
+ max_wal_size = 128MB
+ });
-# Internal method to set up trusted pg_hba.conf for replication. Not
-# documented because you shouldn't use it, it's called automatically if needed.
+ $self->set_replication_conf;
+
+ return;
+}
+
+# Internal to set up trusted pg_hba.conf for replication. Not documented
+# because you shouldn't use it, it's called automatically if needed.
sub set_replication_conf
{
my ($self) = @_;
@@ -398,6 +432,15 @@ sub set_replication_conf
return;
}
+# Internal methods to track capabilities depending on the PostgreSQL major
+# version used
+
+sub can_slots { return 1 }
+sub can_log_hints { return 1 }
+sub can_restart_after_crash { return 1 }
+sub can_skip_init_fsync { return 1 }
+
+
=pod
=item $node->init(...)
@@ -429,6 +472,7 @@ sub init
my $port = $self->port;
my $pgdata = $self->data_dir;
my $host = $self->host;
+ my @cmd;
local %ENV = $self->_get_env();
@@ -438,19 +482,25 @@ sub init
mkdir $self->backup_dir;
mkdir $self->archive_dir;
- TestLib::system_or_bail('initdb', '-D', $pgdata, '-A', 'trust', '-N',
- @{ $params{extra} });
+ @cmd = ( 'initdb', '-D', $pgdata, '-A', 'trust' );
+ push @cmd, '-N' if $self->can_skip_init_fsync;
+ push @cmd, @{ $params{extra} } if defined $params{extra};
+
+ TestLib::system_or_bail(@cmd);
TestLib::system_or_bail($ENV{PG_REGRESS}, '--config-auth', $pgdata,
@{ $params{auth_extra} });
open my $conf, '>>', "$pgdata/postgresql.conf";
print $conf "\n# Added by PostgresNode.pm\n";
print $conf "fsync = off\n";
- print $conf "restart_after_crash = off\n";
+ print $conf "restart_after_crash = off\n" if $self->can_restart_after_crash;
print $conf "log_line_prefix = '%m [%p] %q%a '\n";
print $conf "log_statement = all\n";
- print $conf "log_replication_commands = on\n";
- print $conf "wal_retrieve_retry_interval = '500ms'\n";
+ if ($self->version >= '9.5.0')
+ {
+ print $conf "log_replication_commands = on\n";
+ print $conf "wal_retrieve_retry_interval = '500ms'\n";
+ }
# If a setting tends to affect whether tests pass or fail, print it after
# TEMP_CONFIG. Otherwise, print it before TEMP_CONFIG, thereby permitting
@@ -463,31 +513,8 @@ sub init
# concurrently must not share a stats_temp_directory.
print $conf "stats_temp_directory = 'pg_stat_tmp'\n";
- if ($params{allows_streaming})
- {
- if ($params{allows_streaming} eq "logical")
- {
- print $conf "wal_level = logical\n";
- }
- else
- {
- print $conf "wal_level = replica\n";
- }
- print $conf "max_wal_senders = 10\n";
- print $conf "max_replication_slots = 10\n";
- print $conf "wal_log_hints = on\n";
- print $conf "hot_standby = on\n";
- # conservative settings to ensure we can run multiple postmasters:
- print $conf "shared_buffers = 1MB\n";
- print $conf "max_connections = 10\n";
- # limit disk space consumption, too:
- print $conf "max_wal_size = 128MB\n";
- }
- else
- {
- print $conf "wal_level = minimal\n";
- print $conf "max_wal_senders = 0\n";
- }
+ print $conf "wal_level = minimal\n";
+ print $conf "max_wal_senders = 0\n";
print $conf "port = $port\n";
if ($use_tcp)
@@ -505,8 +532,8 @@ sub init
chmod($self->group_access ? 0640 : 0600, "$pgdata/postgresql.conf")
or die("unable to set permissions for $pgdata/postgresql.conf");
- $self->set_replication_conf if $params{allows_streaming};
- $self->enable_archiving if $params{has_archiving};
+ $self->allows_streaming($params{allows_streaming}) if $params{allows_streaming};
+ $self->enable_archiving if $params{has_archiving};
return;
}
@@ -986,8 +1013,8 @@ primary_conninfo='$root_connstr'
sub enable_restoring
{
my ($self, $root_node, $standby) = @_;
- my $path = TestLib::perl2host($root_node->archive_dir);
- my $name = $self->name;
+ my $path = TestLib::perl2host($root_node->archive_dir);
+ my $name = $self->name;
print "### Enabling WAL restore for node \"$name\"\n";
@@ -1038,7 +1065,7 @@ sub set_recovery_mode
=item $node->set_standby_mode()
-Place standby.signal file.
+Place standby.signal file or set standby_mode = on.
=cut
@@ -1193,6 +1220,13 @@ sub get_new_node
$node->{_install_path} = $params{install_path};
}
+ # validate install path and set version
+ # FIXME: this should probably go to the constructor as various
+ # methods need to be able to read the cluster version
+ $node->_read_pg_config;
+
+ bless $node, $node->version->get_class;
+
# Add node to list of nodes
push(@all_nodes, $node);
@@ -1270,6 +1304,48 @@ sub _get_env
}
return (%inst_env);
}
+
+# Private routine to run the pg_config binary found in our environment (or in
+# our install_path, if we have one), and collect all fields that matter to us.
+#
+sub _read_pg_config
+{
+ my ($self, $inst) = @_;
+ my $pg_config = "pg_config";
+
+ if (defined $inst)
+ {
+ # If the _install_path is invalid, our PATH variables might find an
+ # unrelated pg_config executable elsewhere. Sanity check the
+ # directory.
+ BAIL_OUT("directory not found: $inst")
+ unless -d $inst;
+
+ # If the directory exists but is not the root of a postgresql
+ # installation, or if the user configured using
+ # --bindir=$SOMEWHERE_ELSE, we're not going to find pg_config, so
+ # complain about that, too.
+ $pg_config = "$inst/bin/pg_config";
+ BAIL_OUT("pg_config not found: $pg_config")
+ unless -e $pg_config;
+ BAIL_OUT("pg_config not executable: $pg_config")
+ unless -x $pg_config;
+
+ # Leave $pg_config install_path qualified, to be sure we get the right
+ # version information, below, or die trying
+ }
+
+ local %ENV = $self->_get_env();
+
+ # We only want the version field
+ open my $fh, "-|", $pg_config, "--version"
+ or
+ BAIL_OUT("$pg_config failed: $!");
+ my $version_line = <$fh>;
+ close $fh or die;
+
+ $self->{_pg_version} = PostgresVersion->new($version_line);
+}
=pod
@@ -1382,6 +1458,11 @@ END
$? = $exit_code;
}
+sub version {
+ my $self = shift;
+ return $self->{_pg_version};
+}
+
=pod
=item $node->teardown_node()
@@ -1920,17 +2001,7 @@ sub connect_ok
if (@log_like or @log_unlike)
{
# Don't let previous log entries match for this connection.
- # On Windows, the truncation would not work, so rotate the log
- # file before restarting the server afresh.
- if ($TestLib::windows_os)
- {
- $self->rotate_logfile;
- $self->restart;
- }
- else
- {
- truncate $self->logfile, 0;
- }
+ truncate $self->logfile, 0;
}
# Never prompt for a password, any callers of this routine should
@@ -2004,17 +2075,7 @@ sub connect_fails
if (@log_like or @log_unlike)
{
# Don't let previous log entries match for this connection.
- # On Windows, the truncation would not work, so rotate the log
- # file before restarting the server afresh.
- if ($TestLib::windows_os)
- {
- $self->rotate_logfile;
- $self->restart;
- }
- else
- {
- truncate $self->logfile, 0;
- }
+ truncate $self->logfile, 0;
}
# Never prompt for a password, any callers of this routine should
@@ -2304,8 +2365,12 @@ This is not a test. It die()s on failure.
sub wait_for_catchup
{
my ($self, $standby_name, $mode, $target_lsn) = @_;
+ my $lsn_expr;
+ my $query;
+ my %valid_modes;
+
$mode = defined($mode) ? $mode : 'replay';
- my %valid_modes =
+ %valid_modes =
('sent' => 1, 'write' => 1, 'flush' => 1, 'replay' => 1);
croak "unknown mode $mode for 'wait_for_catchup', valid modes are "
. join(', ', keys(%valid_modes))
@@ -2316,7 +2381,7 @@ sub wait_for_catchup
{
$standby_name = $standby_name->name;
}
- my $lsn_expr;
+
if (defined($target_lsn))
{
$lsn_expr = "'$target_lsn'";
@@ -2325,16 +2390,19 @@ sub wait_for_catchup
{
$lsn_expr = 'pg_current_wal_lsn()';
}
- print "Waiting for replication conn "
- . $standby_name . "'s "
- . $mode
- . "_lsn to pass "
- . $lsn_expr . " on "
- . $self->name . "\n";
- my $query =
- qq[SELECT $lsn_expr <= ${mode}_lsn AND state = 'streaming' FROM pg_catalog.pg_stat_replication WHERE application_name = '$standby_name';];
+
+ print "Waiting for replication conn ${standby_name}'s ${mode}_lsn "
+ . "to pass $lsn_expr on " . $self->name . "\n";
+
+ $query = qq[
+ SELECT $lsn_expr <= ${mode}_lsn AND state = 'streaming'
+ FROM pg_catalog.pg_stat_replication
+ WHERE application_name = '$standby_name'
+ ];
+
$self->poll_query_until('postgres', $query)
or croak "timed out waiting for catchup";
+
print "done\n";
return;
}
@@ -2556,4 +2624,506 @@ sub pg_recvlogical_upto
=cut
+package PostgresNode13;
+
+use strict;
+use warnings;
+use parent 'PostgresNode';
+
+
+package PostgresNode12;
+
+use strict;
+use warnings;
+use parent 'PostgresNode';
+
+package PostgresNode11;
+
+use strict;
+use warnings;
+use Carp;
+use parent 'PostgresNode';
+
+# superuser_reserved_connections + max_wal_senders must be less
+# than max_connections
+sub allows_streaming
+{
+ my ($self, $allows_streaming) = @_;
+ my $pgdata = $self->data_dir;
+ my $wal_level;
+
+ if ($allows_streaming eq "logical")
+ {
+ $wal_level = "logical";
+ }
+ else
+ {
+ $wal_level = "replica";
+ }
+
+ $self->append_conf( 'postgresql.conf', qq{
+ wal_level = $wal_level
+ max_wal_senders = 5
+ max_replication_slots = 10
+ wal_log_hints = on
+ hot_standby = on
+ # conservative settings to ensure we can run multiple postmasters:
+ shared_buffers = 1MB
+ max_connections = 10
+ # limit disk space consumption, too:
+ max_wal_size = 128MB
+ });
+
+ $self->set_replication_conf;
+
+ return;
+}
+
+# standby mode set as GUC in recovery.conf file
+sub set_standby_mode
+{
+ my ($self) = @_;
+
+ $self->append_conf( 'recovery.conf', 'standby_mode = on');
+
+ return;
+}
+
+# recovery mode when recovery.conf file exists with standby_mode = off
+sub set_recovery_mode
+{
+ my ($self) = @_;
+
+ $self->append_conf( 'recovery.conf', 'standby_mode = off');
+
+ return;
+}
+
+# Internal routine to enable archive recovery command on a standby node
+sub enable_restoring
+{
+ my ($self, $root_node, $standby) = @_;
+ my $path = TestLib::perl2host($root_node->archive_dir);
+ my $name = $self->name;
+
+ print "### Enabling WAL restore for node \"$name\"\n";
+
+ # FIXME: use a dedicated command to build the restore command?
+ # On Windows, the path specified in the restore command needs to use
+ # double back-slashes to work properly and to be able to detect properly
+ # the file targeted by the copy command, so the directory value used
+ # in this routine, using only one back-slash, need to be properly changed
+ # first. Paths also need to be double-quoted to prevent failures where
+ # the path contains spaces.
+ $path =~ s{\\}{\\\\}g if ($TestLib::windows_os);
+ my $copy_command =
+ $TestLib::windows_os
+ ? qq{copy "$path\\\\%f" "%p"}
+ : qq{cp "$path/%f" "%p"};
+
+ $self->append_conf(
+ 'recovery.conf', qq(
+restore_command = '$copy_command'
+));
+ if ($standby)
+ {
+ $self->set_standby_mode();
+ }
+ else
+ {
+ $self->set_recovery_mode();
+ }
+ return;
+}
+
+# Internal routine to enable streaming replication on a standby node.
+# * up to version 11, replication setting is in recovery.conf.
+# * up to version 11, we need to explicitly set application_name as cluster_name
+# is not used as a fallback.
+sub enable_streaming
+{
+ my ($self, $root_node) = @_;
+ my $root_connstr = $root_node->connstr;
+ my $name = $self->name;
+
+ print "### Enabling streaming replication for node \"$name\"\n";
+ $self->append_conf(
+ 'recovery.conf', qq(
+primary_conninfo='$root_connstr application_name=$name'
+));
+ $self->set_standby_mode();
+ return;
+}
+
+package PostgresNode10;
+
+use strict;
+use warnings;
+use parent -norequire, 'PostgresNode11';
+
+package PostgresNode96;
+
+use strict;
+use warnings;
+use Carp;
+use Scalar::Util qw(blessed);
+use parent -norequire, 'PostgresNode11';
+
+# pg_ctl doesn't wait by default for full-start in 9.6 and before
+sub start
+{
+ my ($self, %params) = @_;
+ my $port = $self->port;
+ my $pgdata = $self->data_dir;
+ my $name = $self->name;
+ my $ret;
+
+ BAIL_OUT("node \"$name\" is already running") if defined $self->{_pid};
+
+ print("### Starting node \"$name\"\n");
+
+ # Temporarily unset PGAPPNAME so that the server doesn't
+ # inherit it. Otherwise this could affect libpqwalreceiver
+ # connections in confusing ways.
+ local %ENV = $self->_get_env(PGAPPNAME => undef);
+
+ # Note: We set the cluster_name here, not in postgresql.conf (in
+ # sub init) so that it does not get copied to standbys.
+ $ret = TestLib::system_log('pg_ctl', '-D', $self->data_dir, '-l',
+ $self->logfile, '-o', "--cluster-name=$name", '-w', 'start');
+
+ if ($ret != 0)
+ {
+ print "# pg_ctl start failed; logfile:\n";
+ print TestLib::slurp_file($self->logfile);
+ BAIL_OUT("pg_ctl start failed") unless $params{fail_ok};
+ return 0;
+ }
+
+ $self->_update_pid(1);
+ return 1;
+}
+
+# '--no-sync' doesn't exist in 9.6 and before
+sub backup
+{
+ my ($self, $backup_name, %params) = @_;
+ my $backup_path = $self->backup_dir . '/' . $backup_name;
+ my $name = $self->name;
+
+ local %ENV = $self->_get_env();
+
+ print "# Taking pg_basebackup $backup_name from node \"$name\"\n";
+ TestLib::system_or_bail(
+ 'pg_basebackup', '-D', $backup_path, '-h',
+ $self->host, '-p', $self->port, '--checkpoint',
+ 'fast', @{ $params{backup_options} });
+ print "# Backup finished\n";
+ return;
+}
+
+# need to explicitly allow replication in pg_hba.conf for 9.6 and before
+sub set_replication_conf
+{
+ my ($self) = @_;
+ my $pgdata = $self->data_dir;
+
+ $self->host eq $test_pghost
+ or croak "set_replication_conf only works with the default host";
+
+ open my $hba, '>>', "$pgdata/pg_hba.conf";
+ print $hba "\n# Allow replication (set up by PostgresNode.pm)\n";
+ if ($TestLib::windows_os && !$TestLib::use_unix_sockets)
+ {
+ print $hba
+ "host replication all $test_localhost/32 sspi include_realm=1 map=regress\n";
+ }
+ else {
+ print $hba "local replication all trust\n";
+ }
+
+ close $hba;
+ return;
+}
+
+# various function have been renamed after 9.6
+sub lsn
+{
+ my ($self, $mode) = @_;
+ my %modes = (
+ 'insert' => 'pg_current_xlog_insert_location()',
+ 'flush' => 'pg_current_xlog_flush_location()',
+ 'write' => 'pg_current_xlog_location()',
+ 'receive' => 'pg_last_xlog_receive_location()',
+ 'replay' => 'pg_last_xlog_replay_location()');
+
+ $mode = '<undef>' unless defined $mode;
+ croak "unknown mode for 'lsn': '$mode', valid modes are "
+ . join(', ', keys %modes)
+ if !defined($modes{$mode});
+
+ my $result = $self->safe_psql('postgres', "SELECT $modes{$mode}");
+ chomp($result);
+ if ($result eq '')
+ {
+ return;
+ }
+ else
+ {
+ return $result;
+ }
+}
+
+# field renamed after 9.6
+sub wait_for_catchup
+{
+ my ($self, $standby_name, $mode, $target_lsn) = @_;
+ my $lsn_expr;
+ my $query;
+ my %valid_modes;
+
+ $mode = defined($mode) ? $mode : 'replay';
+ %valid_modes =
+ ('sent' => 1, 'write' => 1, 'flush' => 1, 'replay' => 1);
+ croak "unknown mode $mode for 'wait_for_catchup', valid modes are "
+ . join(', ', keys(%valid_modes))
+ unless exists($valid_modes{$mode});
+
+ # Allow passing of a PostgresNode instance as shorthand
+ if (blessed($standby_name) && $standby_name->isa("PostgresNode"))
+ {
+ $standby_name = $standby_name->name;
+ }
+
+ if (defined($target_lsn))
+ {
+ $lsn_expr = "'$target_lsn'";
+ }
+ else
+ {
+ $lsn_expr = 'pg_current_wal_lsn()';
+ }
+
+ print "Waiting for replication conn ${standby_name}'s ${mode}_location "
+ . "to pass $lsn_expr on " . $self->name . "\n";
+
+ $query = qq[
+ SELECT $lsn_expr <= ${mode}_location AND state = 'streaming'
+ FROM pg_catalog.pg_stat_replication
+ WHERE application_name = '$standby_name'
+ ];
+
+ $self->poll_query_until('postgres', $query)
+ or croak "timed out waiting for catchup";
+
+ print "done\n";
+ return;
+}
+
+
+package PostgresNode95;
+
+use strict;
+use warnings;
+use parent -norequire, 'PostgresNode96';
+
+# "wal_level = replicat" does not exist in 9.5.
+sub allows_streaming {
+ my $self = shift;
+
+ $self->SUPER::allows_streaming(@_);
+
+ $self->append_conf('postgresql.conf', 'wal_level = hot_standby');
+
+ return;
+}
+
+
+package PostgresNode94;
+
+use strict;
+use warnings;
+use parent -norequire, 'PostgresNode95';
+use Time::HiRes qw(usleep);
+
+# "max_wal_size" does not exists in 9.4. No need to lower "checkpoint_segments"
+# as it is already low.
+# Moreover, we can not just overload wal_level as 9.4 blocks on first bad
+# GUC value.
+sub allows_streaming
+{
+ my ($self, $allows_streaming) = @_;
+ my $pgdata = $self->data_dir;
+ my $wal_level;
+
+ if ($allows_streaming eq "logical")
+ {
+ $wal_level = "logical";
+ }
+ else
+ {
+ $wal_level = "hot_standby";
+ }
+
+ $self->append_conf( 'postgresql.conf', qq{
+ wal_level = $wal_level
+ max_wal_senders = 5
+ max_replication_slots = 10
+ wal_log_hints = on
+ hot_standby = on
+ # conservative settings to ensure we can run multiple postmasters:
+ shared_buffers = 1MB
+ max_connections = 10
+ });
+
+ $self->set_replication_conf;
+
+ return;
+}
+
+# * "cluster-name" not supported in 9.4 and before
+# * pg_ctl -w does not wait for postmaster.pid to be ready
+# see: f13ea95f9e473
+sub start
+{
+ my ($self, %params) = @_;
+ my $port = $self->port;
+ my $pgdata = $self->data_dir;
+ my $name = $self->name;
+ my $pidfile = $self->data_dir . "/postmaster.pid";
+ my $max_attempts = 300; # 30s
+ my $ret;
+
+ BAIL_OUT("node \"$name\" is already running") if defined $self->{_pid};
+
+ print("### Starting node \"$name\"\n");
+
+ # Temporarily unset PGAPPNAME so that the server doesn't
+ # inherit it. Otherwise this could affect libpqwalreceiver
+ # connections in confusing ways.
+ local %ENV = $self->_get_env(PGAPPNAME => undef);
+
+ # Note: We set the cluster_name here, not in postgresql.conf (in
+ # sub init) so that it does not get copied to standbys.
+ $ret = TestLib::system_log('pg_ctl', '-D', $self->data_dir, '-l',
+ $self->logfile, '-w', 'start');
+
+ while ($max_attempts and not -f $pidfile)
+ {
+ $max_attempts--;
+ # Wait 0.1 second before retrying.
+ usleep(100_000);
+ }
+
+ if ($ret != 0)
+ {
+ print "# pg_ctl start failed; logfile:\n";
+ print TestLib::slurp_file($self->logfile);
+ BAIL_OUT("pg_ctl start failed") unless $params{fail_ok};
+ return 0;
+ }
+
+ if (not -f $pidfile) {
+ print "# timeout while waiting for postmaster.pid; logfile:\n";
+ print TestLib::slurp_file($self->logfile);
+ BAIL_OUT("pg_ctl start failed") unless $params{fail_ok};
+ return 0;
+ }
+
+ $self->_update_pid(1);
+ return 1;
+}
+
+
+package PostgresNode93;
+
+use strict;
+use warnings;
+use parent -norequire, 'PostgresNode94';
+
+
+# "wal_level = logical" doesn't exists
+sub allows_streaming
+{
+ my ($self, $allows_streaming) = @_;
+ my $pgdata = $self->data_dir;
+
+ $self->append_conf( 'postgresql.conf', qq{
+ wal_level = hot_standby
+ max_wal_senders = 5
+ hot_standby = on
+ # conservative settings to ensure we can run multiple postmasters:
+ shared_buffers = 1MB
+ max_connections = 10
+ });
+
+ $self->set_replication_conf;
+
+ return;
+}
+
+sub can_slots { return 0 }
+sub can_log_hints { return 0 }
+
+package PostgresNode92;
+
+use strict;
+use warnings;
+use parent -norequire, 'PostgresNode93';
+use TestLib ();
+
+sub can_skip_init_fsync { return 0 }
+
+sub init
+{
+ my $self = shift;
+
+ $self->SUPER::init(@_);
+ $self->rename_unix_socket_dir;
+
+ return;
+}
+
+sub init_from_backup
+{
+ my $self = shift;
+
+ $self->SUPER::init_from_backup(@_);
+ $self->rename_unix_socket_dir;
+
+ return;
+}
+
+sub rename_unix_socket_dir
+{
+ my $self = shift;
+ my $file = $self->data_dir ."/postgresql.conf";
+ my $conf;
+
+ $conf = TestLib::slurp_file($file);
+
+ $conf =~ s/unix_socket_directories/unix_socket_directory/g;
+
+ open my $fd, '>', $file;
+ print $fd $conf;
+ close $fd;
+
+ return;
+}
+
+package PostgresNode91;
+
+use strict;
+use warnings;
+use parent -norequire, 'PostgresNode92';
+
+
+package PostgresNode90;
+
+use strict;
+use warnings;
+use parent -norequire, 'PostgresNode92';
+
+sub can_restart_after_crash { return 0 }
+
1;
diff --git a/src/test/perl/PostgresVersion.pm b/src/test/perl/PostgresVersion.pm
new file mode 100644
index 0000000000..ca8c0ffe6f
--- /dev/null
+++ b/src/test/perl/PostgresVersion.pm
@@ -0,0 +1,65 @@
+#!/usr/bin/perl
+
+package PostgresVersion;
+
+use strict;
+use warnings;
+use Carp;
+
+use overload '""' => sub { $_[0]->{'version'} },
+ #'>' => \&vers_gt,
+ '<=>' => \&vers_cmp;
+
+sub new {
+ my $class = shift;
+ my $ver = shift;
+ my $errmsg = "could not parse pg_config --version output: $ver";
+ my $self;
+
+ $self->{'vernum'} = 0;
+ $self->{'version'} = 0;
+
+ $ver =~ /(?:PostgreSQL )?(\d+)\.(\d+)(?:\.(\d+))?/;
+
+ croak $errmsg unless defined $1 and defined $2;
+
+ $self->{'version'} = $1;
+ $self->{'vernum'} += 10000 * $1;
+ $self->{'version'} .= ".$2";
+
+ if ($self->{'vernum'} >= 100000) {
+ croak $errmsg if defined $3;
+ $self->{'vernum'} += $2;
+ $self->{'class'} = "$1";
+ }
+ else {
+ #croak $errmsg unless defined $3;
+ my $minor = defined $3 ? $3 : 0;
+ $self->{'vernum'} += 100 * $2 + $minor;
+ $self->{'version'} .= ".$minor";
+ $self->{'class'} = "$1$2"
+ }
+
+ return bless $self, $class
+}
+
+sub get_class {
+ my $self = shift;
+ return "PostgresNode$self->{'class'}";
+}
+
+sub vers_cmp {
+ my ($a, $b, $swapped) = @_;
+ my $res = 1;
+
+ $b = PostgresVersion->new($b) unless ref($b) eq 'PostgresVersion';
+
+ return 0 if $a->{'vernum'} == $b->{'vernum'};
+ $res = -1 if $a->{'vernum'} < $b->{'vernum'};
+
+ $res *= -1 if $swapped;
+
+ return $res;
+}
+
+1
--
2.20.1
