How to transfer files from another server, using F

Question

I am trying to find a way to transfer files from server-to-server. The source server can be any platform, and we may not even really know anything about it except that it supports FTP.

A number of posts I have found on SO recommend using scp, sftp, rsync, or wget for this purpose. Given that this PHP script needs to work every time, and the only thing we know for sure is that the source server supports FTP, how can this be achieved?

I found a couple FTP examples on SO, but they weren't explained very well.

We need to be able to download all files and folders, keeping the same directory structure as well.

Answer 1

This should be a comment, but its a bit long. Copying a file over FTP using PHP might be as simple as

file_put_contents($fname
    , file_get_contents('FTP://ftp.example com/path/afile'));

But what do you know about where your PHP code is running? It may not have the capability to

• resolve DNS names
• make client connections to other/remote services
• create a listening data channel (for non-passive data channel)

And we can't answer these questions for you. Hence your first step is to get a proof of concept up and running using similar code to that above before you start worrying about lots of files, directories and synchronisation.

Why the requirement to implement this in PHP?

Answer 2

I have found a PHP class that makes recursive FTP uploads and downloads easy. It can be found here

The code they used is below (The code at the top is example code for downloads, uploads, and error checking):

<?php // example
set_time_limit(0);
require 'ftp.php';


$ftp = new ftp();
$ftp->conn('host', 'username', 'password');
$ftp->get('download/demo', '/demo'); // download live "/demo" folder to local "download/demo"

$ftp->put('/demo/test', 'upload/vjtest'); // upload local "upload/vjtest" to live "/demo/test"

$arr = $ftp->getLogData();
if ($arr['error'] != "")
    echo '<h2>Error:</h2>' . implode('<br />', $arr['error']);
if ($arr['ok'] != "")
    echo '<h2>Success:</h2>' . implode('<br />', $arr['ok']);

---

class ftp {

    private $conn, $login_result, $logData, $ftpUser, $ftpPass, $ftpHost, $retry, $ftpPasv, $ftpMode, $verbose, $logPath, $createMask;

    // --------------------------------------------------------------------

    /**
     * Construct method
     *
     * @param   array   keys[passive_mode(true|false)|transfer_mode(FTP_ASCII|FTP_BINARY)|reattempts(int)|log_path|verbose(true|false)|create_mask(default:0777)]
     * @return void
     */
    function __construct()
    {
        $this->retry = (isset($o['reattempts'])) ? $o['reattempts'] : 3;
        $this->ftpPasv = (isset($o['passive_mode'])) ? $o['passive_mode'] : true;
        $this->ftpMode = (isset($o['transfer_mode'])) ? $o['transfer_mode'] : FTP_BINARY;
        $this->verbose = (isset($o['verbose'])) ? $o['verbose'] : false;
        $this->logPath = (isset($o['log_path'])) ? $o['log_path'] : dirname(__FILE__).'\log'; 
        $this->createMask = (isset($o['create_mask'])) ? $o['create_mask'] : 0777;
    }

    // --------------------------------------------------------------------

    /**
     * Connection method
     *
     * @param   string  hostname
     * @param   string  username
     * @param   string  password
     * @return  void
     */
    public function conn($hostname, $username, $password)
    {   
        $this->ftpUser = $username;
        $this->ftpPass = $password;
        $this->ftpHost = $hostname;

        $this->initConn();
    }

    // --------------------------------------------------------------------

    /**
     * Init connection method - connect to ftp server and set passive mode
     *
     * @return  bool
     */
    function initConn()
    {
        $this->conn = ftp_connect($this->ftpHost);
        $this->login_result = ftp_login($this->conn, $this->ftpUser, $this->ftpPass);
        if($this->conn && $this->login_result)
        {
            ftp_pasv($this->conn, $this->ftpPasv);
            return true;
        }       
        return false;
    }

    // --------------------------------------------------------------------

    /**
     * Put method - upload files(folders) to ftp server
     *
     * @param   string  path to destionation file/folder on ftp
     * @param   string  path to source file/folder on local disk
     * @param   int only for identify reattempt, dont use this param
     * @return  bool
     */
    public function put($destinationFile, $sourceFile, $retry = 0)
    {   
        if(file_exists($sourceFile))
        { 
            if(!$this->isDir($sourceFile, true))
            {
                $this->createSubDirs($destinationFile);
                if(!ftp_put($this->conn, $destinationFile, $sourceFile, $this->ftpMode))
                {
                    $retry++;
                    if($retry > $this->retry)
                    {
                        $this->logData('Error when uploading file: '.$sourceFile.' => '.$destinationFile, 'error');
                        return false;
                    }
                    if($this->verbose) echo 'Retry: '.$retry."\n";
                    $this->reconnect();
                    $this->put($destinationFile, $sourceFile, $retry);
                }
                else
                {
                    $this->logData('Upload:'.$sourceFile.' => '.$destinationFile, 'ok');
                    return true;
                }
            }
            else
            {
                $this->recursive($destinationFile, $sourceFile, 'put');
            }
        }       
    }

    // --------------------------------------------------------------------

    /**
     * Get method - download files(folders) from ftp server
     *
     * @param   string  path to destionation file/folder on local disk
     * @param   string  path to source file/folder on ftp server
     * @param   int only for identify reattempt, dont use this param
     * @return  bool
     */
    public function get($destinationFile, $sourceFile, $retry = 0)
    {
        if(!$this->isDir($sourceFile, false))
        {
            if($this->verbose)echo $sourceFile.' => '.$destinationFile."\n";
            $this->createSubDirs($destinationFile, false, true);
            if(!ftp_get($this->conn, $destinationFile, $sourceFile, $this->ftpMode))
            {
                $retry++;
                if($retry > $this->retry)
                {
                    $this->logData('Error when downloading file: '.$sourceFile.' => '.$destinationFile, 'error');
                    return false;
                }
                if($this->verbose) echo 'Retry: '.$retry."\n";
                $this->reconnect();
                $this->get($destinationFile, $sourceFile, $retry);
            }
            else
            {
                $this->logData('Download:'.$sourceFile.' => '.$destinationFile, 'ok');
                return true;
            }
        }
        else
        {
            $this->recursive($destinationFile, $sourceFile, 'get');
        }
    }

    // --------------------------------------------------------------------

    /**
     * Make dir method - make folder on ftp server or local disk
     *
     * @param   string  path to destionation folder on ftp or local disk
     * @param   bool    true for local, false for ftp
     * @return  bool
     */
    public function makeDir($dir, $local = false)
    {
        if($local)
        {
            if(!file_exists($dir) && !is_dir($dir))return mkdir($dir, $this->createMask); else return true;
        }
        else
        {
            ftp_mkdir($this->conn,$dir);
            return ftp_chmod($this->conn, $this->createMask, $dir);
        }
    }

    // --------------------------------------------------------------------

    /**
     * Cd up method - change working dir up
     *
     * @param   bool    true for local, false for ftp
     * @return  bool
     */
    public function cdUp($local)
    {
        return $local ? chdir('..') : ftp_cdup($this->conn);
    }

    // --------------------------------------------------------------------

    /**
     * List contents of dir method - list all files in specified directory
     *
     * @param   string  path to destionation folder on ftp or local disk
     * @param   bool    true for local, false for ftp
     * @return  bool
     */
    public function listFiles($file, $local = false)
    {
        if(!$this->isDir($file, $local))return false;
        if($local)
        {
            return scandir($file);
        }
        else
        {
            if(!preg_match('/\//', $file))
            {
                return ftp_nlist($this->conn, $file);
            }else
            {
                $dirs = explode('/', $file);
                foreach($dirs as $dir)
                {
                    $this->changeDir($dir, $local);
                }
                $last = count($dirs)-1;
                $this->cdUp($local);
                $list = ftp_nlist($this->conn, $dirs[$last]);
                $i = 0;
                foreach($dirs as $dir)
                {
                    if($i < $last) $this->cdUp($local);
                    $i++;
                }
                return $list;
            }
        }
    }

    // --------------------------------------------------------------------

    /**
     * Returns current working directory
     *
     * @param   bool    true for local, false for ftp
     * @return  bool
     */
    public function pwd($local = false)
    {
        return $local ? getcwd() : ftp_pwd($this->conn);
    }

    // --------------------------------------------------------------------

    /**
     * Change current working directory
     *
     * @param   string  dir name
     * @param   bool    true for local, false for ftp
     * @return  bool
     */
    public function changeDir($dir, $local = false)
    {
        return $local ? chdir($dir) : @ftp_chdir($this->conn, $dir);
    }

    // --------------------------------------------------------------------

    /**
     * Create subdirectories
     *
     * @param   string  path
     * @param   bool    
     * @param   bool    true for local, false for ftp
     * @param   bool    change current working directory back
     * @return  void
     */
    function createSubDirs($file, $last = false, $local = false, $chDirBack = true)
    {
        if(preg_match('/\//',$file))
        {
            $origin = $this->pwd($local);
            if(!$last) $file = substr($file, 0, strrpos($file,'/'));
            $dirs = explode('/',$file);
            foreach($dirs as $dir)
            {
                if(!$this->isDir($dir, $local))
                {
                    $this->makeDir($dir, $local);
                    $this->changeDir($dir, $local);
                }
                else
                {
                    $this->changeDir($dir, $local);
                }
            }
            if($chDirBack) $this->changeDir($origin, $local);
        }
    }

    // --------------------------------------------------------------------

    /**
     * Recursion
     *
     * @param   string  destionation file/folder
     * @param   string  source file/folder
     * @param   string  put or get
     * @return  void
     */
    function recursive($destinationFile, $sourceFile, $mode)
    {
        $local = ($mode == 'put') ? true : false;
        $list = $this->listFiles($sourceFile, $local);
        if($this->verbose) echo "\n".'Folder: '.$sourceFile."\n";
        $this->logData(($mode=='get')?('Download:'):('Upload:').$sourceFile.' => '.$destinationFile, 'ok');       

        if($this->verbose) print_r($list);
        $x=0;
        $z=0;
        if(count($list)==2)// blank folder
        {
            if($mode == 'get')
                $this->makeDir($destinationFile, true);
            if($mode == 'put')
                $this->makeDir($destinationFile);
        }   
        foreach($list as $file)
        {
            if($file == '.' || $file == '..')continue;
            $destFile = $destinationFile.'/'.$file;
            $srcFile = $sourceFile.'/'.$file;
            if($this->isDir($srcFile,$local))
            {
                $this->recursive($destFile, $srcFile, $mode);
            }
            else
            {
                if($local)
                {
                    $this->put($destFile, $srcFile);
                }
                else
                {
                    $this->get($destFile, $srcFile);
                }
            } 
        }
    }

    // --------------------------------------------------------------------

    /**
     * Check if is dir
     *
     * @param   string  path to folder
     * @return  bool
     */
    public function isDir($dir, $local)
    {
        if($local) return is_dir($dir);
        if($this->changeDir($dir))return $this->cdUp(0);
        return false;
    }

    // --------------------------------------------------------------------

    /**
     * Save log data to array
     *
     * @param   string  data
     * @param   string  type(error|ok)
     * @return  void
     */
    function logData($data, $type)
    {
        $this->logData[$type][] = $data;
    }

    // --------------------------------------------------------------------

    /**
     * Get log data array
     *
     * @return  array
     */
    public function getLogData()
    {
        return $this->logData;
    }

    // --------------------------------------------------------------------

    /**
     * Save log data to file
     *
     * @return  void
     */
    public function logDataToFiles()
    {
        if(!$this->logPath) return false;
        $this->makeDir($this->logPath, true);
        $log = $this->getLogData();  
        $sep = "\n".date('y-m-d H:i:s').' ';
        if($log['error'] != "")
        {
            $logc = date('y-m-d H:i:s').' '.join($sep,$log['error'])."\n";
            $this->addToFile($this->logPath.'/'.$this->ftpUser.'-error.log',$logc);
        }
        if($log['ok'] != "")
        {
            $logc = date('y-m-d H:i:s').' '.join($sep,$log['ok'])."\n";
            $this->addToFile($this->logPath.'/'.$this->ftpUser.'-ok.log',$logc);
        }
    }

    // --------------------------------------------------------------------

    /**
     * Reconnect method
     *
     * @return  void
     */
    public function reconnect()
    {
        $this->closeConn();
        $this->initConn();
    }

    // --------------------------------------------------------------------

    /**
     * Close connection method
     *
     * @return  void
     */
    public function closeConn()
    {
        return ftp_close($this->conn);
    }

    // --------------------------------------------------------------------

    /**
     * Write to file
     *
     * @param   string  path to file
     * @param   string  text
     * @param   string  fopen mode
     * @return  void
     */
    function addToFile($file, $ins, $mode = 'a')
    {
        $fp = fopen($file, $mode);
        fwrite($fp,$ins);
        fclose($fp);
    }

    // --------------------------------------------------------------------

    /**
     * Destruct method - close connection and save log data to file
     *
     * @return  void
     */
    function __destruct()
    {       
        $this->closeConn();
        $this->logDataToFiles();
    }
}

// END ftp class

/* End of file ftp.php */
/* Location: ftp.php */