Selenium-Remote-Driver/lib/Selenium/Binary.pm

package Selenium::Binary;

use File::Which qw/which/;
use IO::Socket::INET;
use Selenium::Waiter qw/wait_until/;

require Exporter;
our @ISA = qw/Exporter/;
our @EXPORT = qw/start_binary_on_port/;

sub start_binary_on_port {
    my ($process, $port) = @_;

    my $executable = _find_executable($process);
    $port = _find_open_port_above($port);
    my $command = _construct_command($executable, $port);

    system($command);
    my $success = wait_until { _probe_port($port) } timeout => 10;
    if ($success) {
        return $port;
    }
    else {
        die 'Unable to connect to the ' . $executable . ' binary on port ' . $port;
    }
}

sub _find_executable {
    my ($binary) = @_;

    my $executable = which($binary);

    if (not defined $executable) {
        die qq(Unable to find the $binary binary in your \$PATH. We'll try falling back to standard Remote Driver);
    }
    else {
        return $executable;
    }
}

sub _construct_command {
    my ($executable, $port) = @_;

    my %args;
    if ($executable =~ /chromedriver$/) {
        %args = (
            port => $port,
            'base-url' => 'wd/hub'
        );
    }
    elsif ($executable =~ /phantomjs$/) {
        %args = (
            webdriver => '127.0.0.1:' . $port
        );
    }

    my @args = map { '--' . $_ . '=' . $args{$_} } keys %args;

    return join(' ', ($executable, @args, '> /dev/null 2>&1 &') );
}

sub _find_open_port_above {
    my ($port) = @_;

    my $free_port = wait_until {
        if (_probe_port($port)) {
            $port++;
            return 0;
        }
        else {
            return $port;
        }
    };

    return $free_port;
}

sub _probe_port {
    my ($port) = @_;

    return IO::Socket::INET->new(
        PeerAddr => '127.0.0.1',
        PeerPort => $port,
        Timeout => 3
    );
}



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