File Coverage

blib/lib/Footprintless/Localhost.pm

Criterion	Covered	Total	%
statement	60	61	98.3
branch	13	20	65.0
condition	6	8	75.0
subroutine	13	13	100.0
pod	8	8	100.0
total	100	110	90.9

use strict;
use warnings;

package Footprintless::Localhost;
$Footprintless::Localhost::VERSION = '1.26';
# ABSTRACT: A localhost alias resolver
# PODNAME: Footprintless::Localhost

use Log::Any;

my $logger              = Log::Any->get_logger();
my $loopback_ipv4_regex = qr/127(?:.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}/;

sub new {
    return bless( {}, shift )->_init(@_);
}

sub _add_alias {
    my ( $self, $alias ) = @_;

    if ($alias) {
        $logger->debugf( 'adding alias [%s]', $alias );
        $self->{aliases}{ lc($alias) } = 1;
    }

    return $self;
}

sub _init {
    my ( $self, %options ) = @_;

    # what gets returned if is_alias(  );
    $self->{empty} = exists( $options{empty} ) ? $options{empty} : 1;
    $self->{etc_hosts_file} = $options{etc_hosts_file} || '/etc/hosts';

    $self->_add_alias('localhost')->_add_alias('127.0.0.1')
        unless ( $options{none} );

    if ( $options{aliases} ) {
        $self->_add_alias($_) foreach @{ $options{aliases} };
    }

    return $self;
}

sub is_alias {
    my ( $self, $hostname ) = @_;

    if ($hostname) {
        return ( $self->{loaded}{'127 subnet'} && $hostname =~ /^\s*$loopback_ipv4_regex\s*$/ )
            || $self->{aliases}{ lc($hostname) };
    }
    else {
        return $self->{empty};
    }
}

sub is_loaded {
    my ( $self, $extra ) = @_;
    return $self->{loaded} && $self->{loaded}{$extra};
}

sub load_127_subnet {
    my ($self) = @_;
    $self->{loaded}{'127 subnet'} = 1;
    return $self;
}

sub load_all {
    return shift->load_etc_hosts()->load_hostfqdn()->load_hostname()->load_127_subnet();
}

sub load_etc_hosts {
    my ( $self, $etc_hosts_file ) = @_;
    $etc_hosts_file = $self->{etc_hosts_file} unless ($etc_hosts_file);

    if ( !$self->{loaded}{'/etc/hosts'} ) {

        # attempt to load aliases from hosts file
        $logger->debug( 'loading /etc/hosts from: %s', $etc_hosts_file );
        eval {
            open( my $handle, '<', $etc_hosts_file );
            while ( my $line = <$handle> ) {
                if ( $line =~ /^$loopback_ipv4_regex\s+(\S.*?)\s*$/ ) {
                    $self->_add_alias($_) foreach map { lc($_) } split( /\s+/, $1 );
                }
            }
            close($handle);
        };
        $self->{loaded}{'/etc/hosts'} = 1;
    }

    return $self;
}

sub load_hostfqdn {
    my ($self) = @_;

    if ( !$self->{loaded}{hostfqdn} ) {

        # if fqdn is present, add it too...
        $logger->debug('loading hostfqdn');
        require Net::Domain;
        $self->_add_alias( Net::Domain::hostfqdn() );
        $self->{loaded}{hostfqdn} = 1;
    }

    return $self;
}

sub load_hostname {
    my ($self) = @_;

    if ( !$self->{loaded}{hostname} ) {

        # load alias from hostname
        $logger->debug('loading hostname');
        eval {
            # hostname() croaks on fail, so just ignore
            require Sys::Hostname;
            $self->_add_alias( Sys::Hostname::hostname() );
        };
        $self->{loaded}{hostname} = 1;
    }

    return $self;
}

1;

__END__