PHP/Codeigniter FTP Timout

Question

I'm trying to access an FTP server from my PHP script using Codeigniter's FTP Library. These functions work great, but when testing the script I discovered that if I attempt to connect to a server that does not exist, the script does not terminate with an error message of any kind.

The page continues to execute, until the web server gives up, returning an empty document.

So I am wondering, is there a way to limit the amount of time that Codeigniter can try to connect to an FTP server, then display a message if that times out?

I tried using the php function set_time_limit(), but it does not behave how I expected it to.

Thanks for your help.

Answer 1

The answer is simple, don't attempt to connect to a server that doesn't exist.

Answer 2

Codeigniter's ftp class uses the underlying ftp_connect php call that supports a 3rd optional parameter, timeout (http://ca2.php.net/manual/en/function.ftp-connect.php).

Codeigniter however does not use it, but allows for extending the default libraries it provides (providing that you're willing to do some work and check that any updates you do to the core will not break the functionality of your extended class). So to solve your problem you could create a new library in you application library folder:

<?php

class MY_FTP extends CI_FTP { //Assuming that in your config.php file, your subclass prefix is set to 'MY_' like so: $config['subclass_prefix'] = 'MY_';

    var $timeout = 90;
    /**
     * FTP Connect
     *
     * @access  public
     * @param   array    the connection values
     * @return  bool
     */
    function connect($config = array())
    {
        if (count($config) > 0)
        {
            $this->initialize($config);
        }

        if (FALSE === ($this->conn_id = ftp_connect($this->hostname, $this->port, $this->timeout)))
        {
            if ($this->debug == TRUE)
            {
                $this->_error('ftp_unable_to_connect');
            }
            return FALSE;
        }

        if ( ! $this->_login())
        {
            if ($this->debug == TRUE)
            {
                $this->_error('ftp_unable_to_login');
            }
            return FALSE;
        }

        // Set passive mode if needed
        if ($this->passive == TRUE)
        {
            ftp_pasv($this->conn_id, TRUE);
        }

        return TRUE;
    }
}
?>

and from your script, you could add to your configuration array the timeout option:

$this->load->library('ftp'); //if ftp is not autoloaded
$ftp_params = array('hostname'=>'1.2.3.4', 'port'=>21, 'timeout'=>10); //timout is 10 seconds instead of default 90
$ftp_conn = $this->ftp->connect($ftp_params);
if(FALSE === $ftp_conn) {
//Code to handle error
}

The ftp class is not designed to give error messages unless the debug parameter is set to TRUE in te config array, in which case it'll just display an error. However it can also be override, because all errors call the function _error() in the class. So you could set 'debug' => true in your $ftp_params array, and add a function in MY_ftp like so:

/**
 * This function overrides 
 */
function _error($line)
{
    $this->error = $line;
}

And then have a function getError() /** * This function overrides */ function get_error() { return $this->error; }

So if

$ftp_conn = $this->ftp->connect($ftp_params);

returns false, you can call

$error = $this->ftp->get_error();

to get your error and display it. Now, you can always customize and have a more complex error handling mechanism by further customizing the class...

Hope it answers your question.