modify-hostalias

#!/usr/local/bin/perl -w
#
# $Id$
#
# script to modify host aliases in the database
#

use strict;
use HOSTDB;
use Getopt::Long;

my %opt = ();
my $res = GetOptions (\%opt,
		      'aliasname=s',
		      'dnsstatus=s',
		      'ttl=s',
		      'comment=s',
		      'debug',
		      'force'
		      );

#die ("$0: Parsing options failed\n") if ($res);

my $debug = defined ($opt{debug});
my $search_for = shift;

sub usage
{
	my $msg = shift;
	# interpolation

	die(<<EOT);
${msg}Syntax: $0 [options] <ID/FQDN>
	options:
		--debug		debug
		--force		well, force
	object modifiers :
		--aliasname		FQDN
		--dnsstatus		ENABLED or DISABLED
		--ttl			DNS TTL
		--comment		Comment abou host

EOT
}

usage('') if (! $search_for);

my $hostdb = HOSTDB::DB->new (inifile => HOSTDB::get_inifile (),
			      debug => $debug
			      );

my $alias = get_alias ($hostdb, $search_for);

die ("$0: Could not find host alias object\n") unless ($alias);

if (! $opt{force}) {
    # do some extra sanity checks if not forced

    if ($opt{aliasname}) {
	my @h = $hostdb->findhost ('guess', $opt{aliasname});

	if (@h) {
	    my $id = $h[0]->id ();
	    my $name = $h[0]->hostname ();
	    die ("$0: At least one host ($name, id $id) matching that name ($opt{aliasname}) already exists\n");
	}
    }
}

$alias->dnsstatus ($opt{dnsstatus})	or die ("$0: Invalid dnsstatus - $alias->{error}\n") if (defined ($opt{dnsstatus}));
$alias->ttl ($opt{ttl})			or die ("$0: Invalid ttl - $alias->{error}\n") if (defined ($opt{ttl}));
$alias->comment ($opt{comment})		or die ("$0: Invalid comment - $alias->{error}\n") if (defined ($opt{comment}));

if (defined ($opt{aliasname})) {
    # setting aliasname. also set dns zone.
    my $z = $hostdb->findzonebyhostname ($opt{aliasname});

    die ("$0: Could not find a suitable dnszone for new aliasname '$opt{aliasname}'\n") unless ($z);
    my $zonename = $z->zonename ();
    $alias->aliasname ($opt{aliasname})	or die ("$0: Invalid aliasname - $alias->{error}\n");
    $alias->dnszone ($zonename)		or die ("$0: Invalid zonename - $alias->{error}\n");
    
    # CNAMEs can't co-exist with any other record in DNS
    die ("Can't have an alias with the same name as a zone ($aliasname)\n") if ($hostdb->findzonebyname ($aliasname));
}

$alias->commit () or die ("$0: Could not commit host alias object - $alias->{error}\n");

exit (0);


sub get_alias
{
    my $hostdb = shift;
    my $search_for = shift;

    my @alias_refs;

    if ($search_for =~ /^\d+$/) {
	# all numeric, look for alias using id
	@alias_refs = $hostdb->findhostaliasbyid ($search_for);
    } else {
	die ("$0: '$search_for' is not a valid hostname (and it does not appear to be an alias ID)!\n")
	    unless ($hostdb->clean_hostname ($search_for));
	@alias_refs = $hostdb->findhostaliasbyname ($search_for);
    }

    if (! @alias_refs) {
	warn ("$0: Search for '$search_for' failed - no match\n");
	return undef;
    }
    if (0 + @alias_refs != 1) {
	my $count = 0 + @alias_refs;
	warn ("$0: Search for '$search_for' failed - more than one ($count) match\n");
	return undef;
    }

    return $alias_refs[0];
}