PowerDNS::Backend::MySQL - Provides an interface to manipulate PowerDNS data in the MySQL Backend.

	use PowerDNS::Backend::MySQL;

	# Setting parameters and their default values.
	my $params = {	db_user			=>	'root',
			db_pass			=>	'',
			db_name			=>	'pdns',
			db_port			=>	'3306',
			db_host			=>	'localhost',
			mysql_print_error	=>	1,
			mysql_warn		=>	1,
			mysql_auto_commit	=>	1,
			mysql_auto_reconnect	=>	1,
			lock_name		=>	'powerdns_backend_mysql',
			lock_timeout		=>	3,
	};

	my $pdns = PowerDNS::Backend::MySQL->new($params);

	PowerDNS::Backend::MySQL provides a layer of abstraction 
	for manipulating the data stored in the PowerDNS MySQL backend.

	my $params = {	db_user			=>	'root',
			db_pass			=>	'',
			db_name			=>	'pdns',
			db_port			=>	'3306',
			db_host			=>	'localhost',
			mysql_print_error	=>	1,
			mysql_warn		=>	1,
			mysql_auto_commit	=>	1,
			mysql_auto_reconnect	=>	1,
			lock_name		=>	'powerdns_backend_mysql',
			lock_timeout		=>	3,
	};

	my $pdns = PowerDNS::Backend::MySQL->new($params);

	Creates a PowerDNS::Backend::MySQL object.

	my $params = {	db_user			=>	'root',
			db_pass			=>	'',
			db_name			=>	'pdns',
			db_port			=>	'3306',
			db_host			=>	'localhost',
			mysql_print_error	=>	1,
			mysql_warn		=>	1,
			mysql_auto_commit	=>	1,
			mysql_auto_reconnect	=>	1,
	};

	my $pdns = PowerDNS::Backend::MySQL->new($params);

	my $domain = 'example.com';
	my $master = '127.0.0.1';

	unless ( $pdns->add_domain(\$domain) )
        { print "Could not add domain : $domain \n"; }

	unless ( $pdns->add_slave(\$domain,\$master) )
        { print "Could not add slave domain : $domain \n"; }

	unless ( $pdns->delete_domain(\$domain) )
	{ print "Could not delete domain : $domain \n"; }

	my $domain_names = $pdns->list_domain_names;

	for my $domain (@$domain_names)
	{ print "$domain \n"; }

	my $type = 'NATIVE';
	my $domain_names = $pdns->list_domain_names_by_type(\$type);

	for my $domain (@$domain_names)
	{ print "$domain \n"; }

	my $master = '127.0.0.1';
	my $domain_names = $pdns->list_slave_domain_names(\$master);

	for my $domain (@$domain_names)
	{ print "$domain \n"; }

	if ( $pdns->domain_exists(\$domain) )
	{ print "The domain $domain does exist. \n"; }
	else
	{ print "The domain $domain does NOT exist. \n"; }

	my $rr = 'CNAME';
	my $records = $pdns->list_records(\$rr , \$domain);
	for my $record  (@$records)
	{ print "@$record\n"; }

	my @rr = ('www.example.com','CNAME','example.com');
	unless ( $pdns->add_record( \@rr , \$domain) )
	{ print "Could not add a RR for $domain \n"; }

	unless ( $pdns->delete_record(\@rr , \$domain) )
	{ print "Could not delete RR for $domain \n"; }

	my $domain = 'example.com';
	my @rr1 = ('localhost.example.com','A','127.0.0.1');
	my @rr2 = ('localhost.example.com','CNAME','example.com');

	unless ( $pdns->update_record(\@rr1 , \@rr2 , \$domain) )
	{ print "Update failed for $domain . \n"; }

	my (@rr1,@rr2,$domain);

	@rr1 = ('example.com','MX');
	@rr2 = ('example.com','MX','mx.example.com');
	$domain = 'example.com';

	unless ( $pdns->update_records( \@rr1 , \@rr2 , \$domain ) )
	{ print "Update failed for $domain . \n"; }

	@rr1 = ('example.com','MX');
	@rr2 = ('example.com','MX','mx.example.com');
	$domain = 'example.com';

	unless ( $pdns->update_or_add_records(\@rr1,\@rr2,\$domain) )
	{ print "Could not update/add record.\n"; }

	my $domain = 'example.com';
	my $content = 'localhost.example.com';
	my $records = $pdns->find_record_by_content(\$content , \$domain);
	my ($name , $type) = @$records;
	print "Name: $name\n";
	print "Type: $type\n";

	my $domain = 'example.com';
	my $name = 'localhost.example.com';
	my $records = $pdns->find_record_by_name(\$name, \$domain);
	my ($content, $type) = @$records;
	print "Content: $content\n";
	print "Type: $type\n";

	my $domain = 'example.com';
	$pdns->make_domain_native(\$domain);

	my $domain = 'example.com';
	my $type = $pdns->get_domain_type(\$domain);
	if ( $type )
	{ print "Type is '$type'\n"; }
	else
	{ print "Domain $domain does not exist.\n" }

	my $master = $pdns->get_master(\$domain);
	print "Master: $master\n";

	my $domain = 'augnix.net';
	unless ( $pdns->increment_serial(\$domain) )
	{ print "Could not increment serial."; }

    perldoc PowerDNS::Backend::MySQL

    You can also look for information at:

	0.09
	$Id: MySQL.pm 1480 2007-12-04 19:29:23Z augie $

# $Id: MySQL.pm 1480 2007-12-04 19:29:23Z augie $
# Provides an interface to manipulate PowerDNS data in the MySQL Backend.

package PowerDNS::Backend::MySQL;

use DBI;
use Carp;
use strict;
use warnings;

our $VERSION = '0.09';

sub new
{
	my $class = shift;
	my $params= shift;
	my $self  = {};

	bless $self , ref $class || $class;
	
	my $db_user = defined $params->{db_user} ? $params->{db_user} : 'root';
	my $db_pass = defined $params->{db_pass} ? $params->{db_pass} : '';
	my $db_name = defined $params->{db_name} ? $params->{db_name} : 'pdns';
	my $db_port = defined $params->{db_port} ? $params->{db_port} : '3306';
	my $db_host = defined $params->{db_host} ? $params->{db_host} : 'localhost';

	$self->{'lock_name'} = defined $params->{lock_name} ? $params->{lock_name} : 'powerdns_backend_mysql';
	$self->{'lock_timeout'} = defined $params->{lock_timeout} ? $params->{lock_timeout} : 3;

	my $mysql_print_error = $params->{mysql_print_error} ? defined $params->{mysql_print_error} : 1;
	my $mysql_warn = $params->{mysql_warn} ? defined $params->{mysql_warn} : 1;
	my $mysql_auto_commit = $params->{mysql_auto_commit} ? defined $params->{mysql_auto_commit} : 1;

	my $mysql_auto_reconnect = $params->{mysql_auto_reconnect} ? defined $params->{mysql_auto_reconnect} : 1;

	my $db_DSN  = "DBI:mysql:database=$db_name;host=$db_host;port=$db_port";

	$self->{'dbh'} = DBI->connect($db_DSN, $db_user, $db_pass, 
		{
			'PrintError' => $mysql_print_error,
			'Warn' => $mysql_warn, 
			'AutoCommit' => $mysql_auto_commit,
		});
	$self->{'dbh'}->{'mysql_auto_reconnect'} = $mysql_auto_reconnect;
	
	$self->{'error_msg'} = undef;

	return $self;
}

sub DESTROY
{
	my $self = shift;
	if ( defined $self->{'dbh'} )
	{
		delete $self->{'dbh'} or warn "$!\n";
	}
}

# Internal Method.
# Get a lock on the database to avoid race conditions.
# Returns 1 on success and 0 on failure.
sub _lock
{
        my $self = shift;
	my $lock_name = $self->{'lock_name'};
	my $lock_timeout = $self->{'lock_timeout'};

        my $sth = $self->{'dbh'}->prepare("SELECT GET_LOCK('$lock_name',$lock_timeout)");
        if ( ! $sth->execute )
        {
             return 0;
        }

        my ($rv) = $sth->fetchrow_array;
        return $rv;
}

# Internal Method.
# Release a lock on the database.
# Returns 1 on success and 0 on failure.
sub _unlock
{
        my $self = shift;
	my $lock_name = $self->{'lock_name'};

        my $sth = $self->{'dbh'}->prepare("SELECT RELEASE_LOCK('$lock_name')");
        if ( ! $sth->execute )
        {
             return 0;
        }

        my ($rv) = $sth->fetchrow_array;
        return $rv;
}

sub add_domain($) 
{
	my $self = shift;
	my $domain = shift;
	
	my $sth = $self->{'dbh'}->prepare("INSERT INTO domains (name,type) VALUES (?,'NATIVE')");
	if ( $sth->execute($$domain) != 1 ) { return 0; }

	return 1;
}

sub add_slave($$)
{
	my $self   = shift;
	my $domain = shift;
	my $master = shift;
	my $sth;

	if ( $self->domain_exists($domain) )
	{
		$sth = $self->{'dbh'}->prepare("UPDATE domains set master = ? , type = 'SLAVE' WHERE name = ?");
	        if ( $sth->execute($$master,$$domain) != 1 ) { return 0; }
	}
	else
	{
		$sth = $self->{'dbh'}->prepare("INSERT INTO domains (name,master,type) VALUES(?,?,'SLAVE')");
	        if ( $sth->execute($$domain,$$master) != 1 ) { return 0; }
	}

	return 1;
}

sub delete_domain($) 
{
	my $self = shift;
	my $domain = shift;
		
	# Remove domain.
	my $sth = $self->{'dbh'}->prepare("DELETE FROM domains WHERE name = ?");
	if ( $sth->execute($$domain) != 1 ) { return 0; }
	
	return 1;
}

sub list_domain_names
{
	my $self = shift;
	my @domains;

	# Grab the domain names.
	my $sth = $self->{'dbh'}->prepare("SELECT name FROM domains");
	$sth->execute;

	while ( my ($domain) = $sth->fetchrow_array )
	{ push @domains , $domain; }

	return \@domains;
}

sub list_domain_names_by_type($)
{
	my $self = shift;
	my $type = shift;
	my @domains;

	# Grab the domain names.
	my $sth = $self->{'dbh'}->prepare("SELECT name FROM domains WHERE type = ?");
	$sth->execute($$type);

	while ( my ($domain) = $sth->fetchrow_array )
	{ push @domains , $domain; }

	return \@domains;
}

sub list_slave_domain_names($)
{
	my $self = shift;
	my $master = shift;
	my @domains;

	# Grab the domain names.
	my $sth = $self->{'dbh'}->prepare("SELECT name FROM domains WHERE TYPE = 'SLAVE' AND master = ?");
	$sth->execute($$master);

	while ( my ($domain) = $sth->fetchrow_array )
	{ push @domains , $domain; }

	return \@domains;
}

sub domain_exists($)
{
	my $self = shift;
	my $domain = shift;
	
	my $sth = $self->{'dbh'}->prepare("SELECT id FROM domains WHERE name = ?");
	$sth->execute($$domain) or return 0;
	
	my @record = $sth->fetchrow_array;
	
	scalar(@record) ? return 1 : return 0;
}

sub list_records($$)
{
	my $self = shift;
	my $rr = shift;
	my $domain = shift;
	my @records;
	
	my $sth = $self->{'dbh'}->prepare("SELECT name,content,ttl,prio FROM records WHERE type = ? and domain_id = (SELECT id FROM domains WHERE name = ?)");
	$sth->execute($$rr,$$domain);
	
	while ( my ($name,$content,$ttl,$prio) = $sth->fetchrow_array )
	{ push @records , [ ($name,$content,$ttl,$prio) ]; } # push anonymous array on to end.
	
	return \@records;
}

sub add_record($$)
{
	my $self = shift;
	my $rr = shift;
	my $domain = shift;
	my ($name , $type , $content , $ttl , $prio) = @$rr;
	
	# Default values.
	if ( ! defined $ttl or $ttl eq '' ) { $ttl = 7200; }
	if ( ! defined $prio or $prio eq '' ) { $prio = 0; }

	# Get a server lock to avoid race condition.
	if ( ! $self->_lock )
	{
		carp("Could not obtain lock.\n");
		return 0;
	}

	my $sth = $self->{'dbh'}->prepare("INSERT INTO records (domain_id,name,type,content,ttl,prio) SELECT id,?,?,?,?,? FROM domains WHERE name = ?");
	if ( $sth->execute($name,$type,$content,$ttl,$prio,$$domain) <= 0 )
	{
		$self->_unlock;
		return 0;
	}

	# Release server lock.
	$self->_unlock;
	
	return 1;
}

sub delete_record($$)
{
	my $self = shift;
	my $rr = shift;
	my $domain = shift;
	my ($name , $type , $content) = @$rr;

	# Get a server lock to avoid race condition.
	if ( ! $self->_lock )
	{
		carp("Could not obtain lock.\n");
		return 0;
	}
	
	my $sth = $self->{'dbh'}->prepare("DELETE FROM records WHERE name=? and type=? and content=? and domain_id = (SELECT id FROM domains WHERE name = ?) LIMIT 1");
	my $rv = $sth->execute($name,$type,$content,$$domain);

	# Release server lock.
	$self->_unlock;

	($rv > 0) ? return 1 : return 0;
}

sub update_record($$$)
{
	my $self = shift;
	my $rr1 = shift;
	my $rr2 = shift;
	my $domain = shift;
	my ($name1 , $type1 , $content1) = @$rr1;
	my ($name2 , $type2 , $content2 , $ttl , $prio) = @$rr2;
	
	# Default values.
	if ( ! defined $ttl or $ttl eq '' ) { $ttl = 7200; }
	if ( ! defined $prio or $prio eq '' ) { $prio = 0; }
	
	# Get a server lock to avoid race condition.
	if ( ! $self->_lock )
	{
		carp("Could not obtain lock.\n");
		return 0;
	}

	my $sth = $self->{'dbh'}->prepare("UPDATE records SET name=? , type=? , content=? , ttl=? , prio=? WHERE name=? and type=? and content=? and domain_id = (SELECT id FROM domains WHERE name = ?) LIMIT 1");
	my $rv = $sth->execute($name2,$type2,$content2,$ttl,$prio,$name1,$type1,$content1,$$domain);

	# Release server lock.
	$self->_unlock;
	
	($rv > 0) ? return 1 : return 0;
}

sub update_records($$$)
{
	my $self = shift;
	my $rr1 = shift;
	my $rr2 = shift;
	my $domain = shift;
	my ($name1 , $type1 ) = @$rr1;
	my ($name2 , $type2 , $content2 , $ttl , $prio) = @$rr2;
	
	# Default values.
	if ( ! defined $ttl or $ttl eq '' ) { $ttl = 7200; }
	if ( ! defined $prio or $prio eq '' ) { $prio = 0; }
	
	# Get a server lock to avoid race condition.
	if ( ! $self->_lock )
	{
		carp("Could not obtain lock.\n");
		return 0;
	}

	my $sth = $self->{'dbh'}->prepare("UPDATE records SET name=? , type=? , content=? , ttl=? , prio=? WHERE name=? and type=? and domain_id = (SELECT id FROM domains WHERE name = ?)");
	# $rv is number of rows affected; it's OK for no rows to be affected; when duplicate data is being updated for example.
	my $rv = $sth->execute($name2,$type2,$content2,$ttl,$prio,$name1,$type1,$$domain);
	
	# Release server lock.
	$self->_unlock;

	($rv > 0) ? return 1 : return 0;
}

sub update_or_add_records($$$)
{
	my $self = shift;
	my $rr1 = shift;
	my $rr2 = shift;
	my $domain = shift;
	my ($name1 , $type1 ) = @$rr1;
	my ($name2 , $type2 , $content2 , $ttl , $prio) = @$rr2;
	
	# Default values.
	if ( ! defined $ttl or $ttl eq '' ) { $ttl = 7200; }
	if ( ! defined $prio or $prio eq '' ) { $prio = 0; }

	# Get a server lock to avoid race condition.
	if ( ! $self->_lock )
	{
		carp("Could not obtain lock.\n");
		return 0;
	}

	# See if record exists in zone.
	my $sth = $self->{'dbh'}->prepare('SELECT COUNT(*) FROM records WHERE name = ? AND type = ? AND domain_id = (SELECT id FROM domains WHERE name = ?)');
	unless ( $sth->execute($name1,$type1,$$domain) )
	{
		$sth->_unlock;
		return 0;
	}
	
	my ($count) = $sth->fetchrow_array;

	if ( $count == 0 ) # Add new record to zone.
	{ 
		my $sth = $self->{'dbh'}->prepare("INSERT INTO records (domain_id,name,type,content,ttl,prio) SELECT id,?,?,?,?,? FROM domains WHERE name = ?");
		if ( $sth->execute($name2,$type2,$content2,$ttl,$prio,$$domain) <= 0 )
		{
			$self->_unlock;
			return 0;
		}
	}
	else # Update existing record in zone.
	{
		my $sth = $self->{'dbh'}->prepare("UPDATE records SET name=? , type=? , content=? , ttl=? , prio=? WHERE name=? and type=? and domain_id = (SELECT id FROM domains WHERE name = ?)");
		if ( $sth->execute($name2,$type2,$content2,$ttl,$prio,$name1,$type1,$$domain) <=0 )
		{
			$self->_unlock;
			return 0;
		}
	}

	# Release server lock.
	$self->_unlock;
	return 1;
}

sub find_record_by_content($$)
{
	my $self = shift;
	my $content = shift;
	my $domain = shift;
	
	my $sth = $self->{'dbh'}->prepare("SELECT name,type FROM records WHERE content = ? AND domain_id = (SELECT id FROM domains WHERE name = ?) LIMIT 1");
	$sth->execute($$content,$$domain);
	
	 my @records = $sth->fetchrow_array;
	
	return \@records;
}

sub find_record_by_name($$)
{
	my $self = shift;
	my $name = shift;
	my $domain = shift;
	
	my $sth = $self->{'dbh'}->prepare("SELECT content,type FROM records WHERE name = ? AND domain_id = (SELECT id FROM domains WHERE name = ?) LIMIT 1");
	$sth->execute($$name,$$domain);
	
	 my @records = $sth->fetchrow_array;
	
	return \@records;
}

sub make_domain_native($)
{
	my $self = shift;
	my $domain = shift;

	my $sth = $self->{'dbh'}->prepare("UPDATE domains set type='NATIVE' , master='' WHERE name=?");
	if ( $sth->execute($$domain) != 1 ) { return 0; }

	return 1;
}

sub get_domain_type($)
{
	my $self = shift;
	my $domain = shift;
	my $type = '';

	my $sth = $self->{'dbh'}->prepare("SELECT type FROM domains WHERE name = ?");
	$sth->execute($$domain);

	($type) = $sth->fetchrow_array;
	return $type;
}

sub get_master($)
{
	my $self   = shift;
	my $domain = shift;
	my $master = '';

	my $sth = $self->{'dbh'}->prepare("SELECT master FROM domains WHERE name = ?");
	$sth->execute($$domain);

	($master) = $sth->fetchrow_array;
	return $master;
}

sub increment_serial($)
{
	my $self = shift;
	my $domain = shift;

	# Get a server lock to avoid race condition.
	if ( ! $self->_lock )
	{
		carp("Could not obtain lock.\n");
		return 0;
	}

	my $sth = $self->{'dbh'}->prepare("SELECT content FROM records WHERE type = 'SOA' AND domain_id = (SELECT id FROM domains WHERE name = ?)");
	unless ( $sth->execute($$domain) )
	{
		$self->_unlock;
		return 0;
	}

	# Grab and split SOA into parts.
	my $soa = $sth->fetchrow_array;

	unless ($soa)
	{ return 0; }
	
	my @soa = split / / , $soa;
	my $soa_date = substr($soa[2],0,8);
	my $now_date = `date +%Y%m%d`; 
	chomp $now_date;
	my $soa_counter = substr($soa[2],-2);

	if ( $soa_date != $now_date )
	{
		$soa[2] = $now_date . '00';
	}
	else
	{
		$soa_counter++;
		$soa_counter %= 100;
		$soa[2] = $now_date . sprintf('%02d',$soa_counter);
	}

	my $new_soa = join ' ' , @soa;

	$sth = $self->{'dbh'}->prepare("UPDATE records SET content = ? WHERE type = 'SOA' AND domain_id = (SELECT id FROM domains WHERE name = ?)");
	if ( $sth->execute($new_soa,$$domain) <= 0 )
	{
		$self->_unlock;
		return 0;
	}

	$self->_unlock;
	return 1;
}

1;