#!/usr/bin/perl -wT
# Show all PostgreSQL clusters in a list
#
# (C) 2005-2009 Martin Pitt <mpitt@debian.org>
# (C) 2013-2018 Christoph Berg <myon@debian.org>
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.

use strict;
use PgCommon;
use Getopt::Long;

sub help ($)
{
    my $exit = shift;
    print "Usage: $0 [-hjs]

Options:
  -h --no-header   Omit column headers in output
  -j --json        JSON output
  -s --start-conf  Include start.conf information in status column
     --help        Print help\n";

     exit $exit;
}

# option handling
my $no_header;
my $json;
my $start_conf;
help(1) unless GetOptions (
    'help' => sub { help(0); },
    'h|no-header' => \$no_header,
    'j|json' => \$json,
    's|start-conf' => \$start_conf,
);

my (@versions, $ls_cluster);
if (@ARGV == 1 and $ARGV[0] =~ m{^(\d+(?:\.\d+)?)[-/]([-.\w]+)$}) {
    push @versions, $1;
    $ls_cluster = $2;
} elsif (@ARGV >= 1) {
    $ARGV[0] =~ /^(\d+(?:\.\d+)?)$/ or error "Invalid version number \"$ARGV[0]\"";
    push @versions, $1;
} else {
    @versions = get_versions();
}
if (@ARGV >= 2 and $ARGV[1] =~ /^([-.\w]+)$/) {
    $ls_cluster = $1;
}

error "Cluster @versions $ls_cluster does not exist"
    if ($ls_cluster and not cluster_exists(@versions, $ls_cluster));

# data collection
my @lines;
push @lines, ['Ver', 'Cluster', 'Port', 'Status', 'Owner', 'Data directory', 'Log file']
    unless ($no_header);
my $jsoninfo = [];

foreach my $v (@versions) {
    my $pg_log = $v >= 10 ? 'log' : 'pg_log'; # log directory in PGDATA changed in PG 10
    my @clusters = $ls_cluster ? $ls_cluster : get_version_clusters $v;
    foreach my $c (@clusters) {
        my %info = cluster_info $v, $c;

        my $status = $info{'running'} ? "online" : "down";
        $status .= ",recovery" if ($info{'recovery'});
        $status .= ",$info{start}" if ($start_conf);

        my $logfile = $info{logfile} // '<unknown>'; # default logfile in /var/log/postgresql
        if (config_bool ($info{config}->{logging_collector})) {
            my $path = $info{config}->{log_directory} || $pg_log;
            my $file = $info{config}->{log_filename} || 'postgresql-%Y-%m-%d_%H%M%S.log';
            $logfile = "$path/$file";
        }
        my $destination = $info{config}->{log_destination} || 'stderr';
        $destination =~ s/stderr/$logfile/;
        my $csvlog = $logfile;
        $csvlog =~ s/(?:\.log)?$/.csv/;
        $destination =~ s/csvlog/$csvlog/;

        push @lines, [$v, $c, $info{'port'} // '<unknown>', $status,
            defined $info{'owneruid'} ? (getpwuid $info{'owneruid'})[0] : '<unknown>',
            $info{'pgdata'} || '<unknown>', $destination];
        $info{version} = $v;
        $info{cluster} = $c;
        push @$jsoninfo, \%info;
    }
}

# output
if ($json) {
    eval { require JSON; };
    error 'Please install JSON.pm for JSON output (Debian: libjson-perl)'
        if ($@);
    print JSON::encode_json($jsoninfo) . "\n";
    exit 0;
}

my @colwidth = qw(1 1 1 1 1 1 1);
foreach my $line (@lines) {
    for (my $i = 0; $i < @$line - 1; $i++) { # skip adjustment for last column
        my $len = length @$line[$i];
        $colwidth[$i] = $len if ($len > $colwidth[$i]);
    }
}

my $color = -t 1; # color output if stdout is a terminal
my $fmtstring = join ' ', map { "%-${_}s" } @colwidth;

foreach my $line (@lines) {
    if ($color and $line->[0] ne 'Ver') { # don't color header
        printf "\033[%dm$fmtstring\033[0m\n",
            ($line->[3] =~ /^online/ ? 32 : 31), # green, red
            @$line;
    } else {
        printf "$fmtstring\n", @$line;
    }
}

__END__

=head1 NAME

pg_lsclusters - show information about all PostgreSQL clusters

=head1 SYNOPSIS

B<pg_lsclusters> [I<options>] [I<version> [I<cluster>]]

=head1 DESCRIPTION

This command list the status and some configuration details of all clusters.
If a version and optionally a cluster name are given, only these are shown.

=head1 OPTIONS

=over 4

=item B<-h>, B<--no-header>

Do not print the column header line.

=item B<-j>, B<--json>

Output information in JSON format. Needs JSON.pm installed.
(Debian package: libjson-perl)

=item B<-s>, B<--start-conf>

Include F<start.conf> information in status column.

=item B<--help>

Print usage help.

=back

=head1 NOTES

The cluster status is shown as B<online> or B<down>. If a F<recovery.conf> file
is found in the data directory, B<,recovery> is appended. The latter needs read
access to the data directory, which only root and the cluster owner have.

The output lines are colored green and red to indicate the cluster status
visually.

=head1 AUTHOR

Martin Pitt L<E<lt>mpitt@debian.orgE<gt>>