/lib/Zend/Service/Amazon/S3/Stream.php

<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Service

 * @subpackage Amazon_S3

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 * @version    $Id: Stream.php 22621 2010-07-18 00:35:48Z torio $

 */



/**

 * @see Zend_Service_Amazon_S3

 */

#require_once 'Zend/Service/Amazon/S3.php';



/**

 * Amazon S3 PHP stream wrapper

 *

 * @category   Zend

 * @package    Zend_Service

 * @subpackage Amazon_S3

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

class Zend_Service_Amazon_S3_Stream

{

    /**

     * @var boolean Write the buffer on fflush()?

     */

    private $_writeBuffer = false;



    /**

     * @var integer Current read/write position

     */

    private $_position = 0;



    /**

     * @var integer Total size of the object as returned by S3 (Content-length)

     */

    private $_objectSize = 0;



    /**

     * @var string File name to interact with

     */

    private $_objectName = null;



    /**

     * @var string Current read/write buffer

     */

    private $_objectBuffer = null;



    /**

     * @var array Available buckets

     */

    private $_bucketList = array();



    /**

     * @var Zend_Service_Amazon_S3

     */

    private $_s3 = null;



    /**

     * Retrieve client for this stream type

     *

     * @param  string $path

     * @return Zend_Service_Amazon_S3

     */

    protected function _getS3Client($path)

    {

        if ($this->_s3 === null) {

            $url = explode(':', $path);



            if (!$url) {

                /**

                 * @see Zend_Service_Amazon_S3_Exception

                 */

                #require_once 'Zend/Service/Amazon/S3/Exception.php';

                throw new Zend_Service_Amazon_S3_Exception("Unable to parse URL $path");

            }



            $this->_s3 = Zend_Service_Amazon_S3::getWrapperClient($url[0]);

            if (!$this->_s3) {

                /**

                 * @see Zend_Service_Amazon_S3_Exception

                 */

                #require_once 'Zend/Service/Amazon/S3/Exception.php';

                throw new Zend_Service_Amazon_S3_Exception("Unknown client for wrapper {$url[0]}");

            }

        }



        return $this->_s3;

    }



    /**

     * Extract object name from URL

     *

     * @param string $path

     * @return string

     */

    protected function _getNamePart($path)

    {

        $url = parse_url($path);

        if ($url['host']) {

            return !empty($url['path']) ? $url['host'].$url['path'] : $url['host'];

        }



        return '';

    }

    /**

     * Open the stream

     *

     * @param  string  $path

     * @param  string  $mode

     * @param  integer $options

     * @param  string  $opened_path

     * @return boolean

     */

    public function stream_open($path, $mode, $options, $opened_path)

    {

        $name = $this->_getNamePart($path);

        // If we open the file for writing, just return true. Create the object

        // on fflush call

        if (strpbrk($mode, 'wax')) {

            $this->_objectName = $name;

            $this->_objectBuffer = null;

            $this->_objectSize = 0;

            $this->_position = 0;

            $this->_writeBuffer = true;

            $this->_getS3Client($path);

            return true;

        }

        else {

            // Otherwise, just see if the file exists or not

            $info = $this->_getS3Client($path)->getInfo($name);

            if ($info) {

                $this->_objectName = $name;

                $this->_objectBuffer = null;

                $this->_objectSize = $info['size'];

                $this->_position = 0;

                $this->_writeBuffer = false;

                $this->_getS3Client($path);

                return true;

            }

        }

        return false;

    }



    /**

     * Close the stream

     *

     * @return void

     */

    public function stream_close()

    {

        $this->_objectName = null;

        $this->_objectBuffer = null;

        $this->_objectSize = 0;

        $this->_position = 0;

        $this->_writeBuffer = false;

        unset($this->_s3);

    }



    /**

     * Read from the stream

     *

     * http://bugs.php.net/21641 - stream_read() is always passed PHP's 

     * internal read buffer size (8192) no matter what is passed as $count 

     * parameter to fread(). 

     *

     * @param  integer $count

     * @return string

     */

    public function stream_read($count)

    {

        if (!$this->_objectName) {

            return false;

        }



        // make sure that count doesn't exceed object size

        if ($count + $this->_position > $this->_objectSize) {

            $count = $this->_objectSize - $this->_position;

        }



        $range_start = $this->_position;

        $range_end = $this->_position+$count;



        // Only fetch more data from S3 if we haven't fetched any data yet (postion=0)

        // OR, the range end position is greater than the size of the current object

        // buffer AND if the range end position is less than or equal to the object's

        // size returned by S3

        if (($this->_position == 0) || (($range_end > strlen($this->_objectBuffer)) && ($range_end <= $this->_objectSize))) {



            $headers = array(

                'Range' => "bytes=$range_start-$range_end"

            );



            $response = $this->_s3->_makeRequest('GET', $this->_objectName, null, $headers);



            if ($response->getStatus() == 206) { // 206 Partial Content

                $this->_objectBuffer .= $response->getBody();

            }

        }



        $data = substr($this->_objectBuffer, $this->_position, $count);

        $this->_position += strlen($data);

        return $data;

    }



    /**

     * Write to the stream

     *

     * @param  string $data

     * @return integer

     */

    public function stream_write($data)

    {

        if (!$this->_objectName) {

            return 0;

        }

        $len = strlen($data);

        $this->_objectBuffer .= $data;

        $this->_objectSize += $len;

        // TODO: handle current position for writing!

        return $len;

    }



    /**

     * End of the stream?

     *

     * @return boolean

     */

    public function stream_eof()

    {

        if (!$this->_objectName) {

            return true;

        }



        return ($this->_position >= $this->_objectSize);

    }



    /**

     * What is the current read/write position of the stream

     *

     * @return integer

     */

    public function stream_tell()

    {

        return $this->_position;

    }



    /**

     * Update the read/write position of the stream

     *

     * @param  integer $offset

     * @param  integer $whence

     * @return boolean

     */

    public function stream_seek($offset, $whence)

    {

        if (!$this->_objectName) {

            return false;

        }



        switch ($whence) {

            case SEEK_CUR:

                // Set position to current location plus $offset

                $new_pos = $this->_position + $offset;

                break;

            case SEEK_END:

                // Set position to end-of-file plus $offset

                $new_pos = $this->_objectSize + $offset;

                break;

            case SEEK_SET:

            default:

                // Set position equal to $offset

                $new_pos = $offset;

                break;

        }

        $ret = ($new_pos >= 0 && $new_pos <= $this->_objectSize);

        if ($ret) {

            $this->_position = $new_pos;

        }

        return $ret;

    }



    /**

     * Flush current cached stream data to storage

     *

     * @return boolean

     */

    public function stream_flush()

    {

        // If the stream wasn't opened for writing, just return false

        if (!$this->_writeBuffer) {

            return false;

        }



        $ret = $this->_s3->putObject($this->_objectName, $this->_objectBuffer);



        $this->_objectBuffer = null;



        return $ret;

    }



    /**

     * Returns data array of stream variables

     *

     * @return array

     */

    public function stream_stat()

    {

        if (!$this->_objectName) {

            return false;

        }



        $stat = array();

        $stat['dev'] = 0;

        $stat['ino'] = 0;

        $stat['mode'] = 0777;

        $stat['nlink'] = 0;

        $stat['uid'] = 0;

        $stat['gid'] = 0;

        $stat['rdev'] = 0;

        $stat['size'] = 0;

        $stat['atime'] = 0;

        $stat['mtime'] = 0;

        $stat['ctime'] = 0;

        $stat['blksize'] = 0;

        $stat['blocks'] = 0;



    if(($slash = strchr($this->_objectName, '/')) === false || $slash == strlen($this->_objectName)-1) {

        /* bucket */

        $stat['mode'] |= 040000;

    } else {

        $stat['mode'] |= 0100000;

    }

           $info = $this->_s3->getInfo($this->_objectName);

        if (!empty($info)) {

            $stat['size']  = $info['size'];

            $stat['atime'] = time();

            $stat['mtime'] = $info['mtime'];

        }



        return $stat;

    }



    /**

     * Attempt to delete the item

     *

     * @param  string $path

     * @return boolean

     */

    public function unlink($path)

    {

        return $this->_getS3Client($path)->removeObject($this->_getNamePart($path));

    }



    /**

     * Attempt to rename the item

     *

     * @param  string  $path_from

     * @param  string  $path_to

     * @return boolean False

     */

    public function rename($path_from, $path_to)

    {

        // TODO: Renaming isn't supported, always return false

        return false;

    }



    /**

     * Create a new directory

     *

     * @param  string  $path

     * @param  integer $mode

     * @param  integer $options

     * @return boolean

     */

    public function mkdir($path, $mode, $options)

    {

        return $this->_getS3Client($path)->createBucket(parse_url($path, PHP_URL_HOST));

    }



    /**

     * Remove a directory

     *

     * @param  string  $path

     * @param  integer $options

     * @return boolean

     */

    public function rmdir($path, $options)

    {

        return $this->_getS3Client($path)->removeBucket(parse_url($path, PHP_URL_HOST));

    }



    /**

     * Attempt to open a directory

     *

     * @param  string $path

     * @param  integer $options

     * @return boolean

     */

    public function dir_opendir($path, $options)

    {



        if (preg_match('@^([a-z0-9+.]|-)+://$@', $path)) {

            $this->_bucketList = $this->_getS3Client($path)->getBuckets();

        }

        else {

            $host = parse_url($path, PHP_URL_HOST);

            $this->_bucketList = $this->_getS3Client($path)->getObjectsByBucket($host);

        }



        return ($this->_bucketList !== false);

    }



    /**

     * Return array of URL variables

     *

     * @param  string $path

     * @param  integer $flags

     * @return array

     */

    public function url_stat($path, $flags)

    {

        $stat = array();

        $stat['dev'] = 0;

        $stat['ino'] = 0;

        $stat['mode'] = 0777;

        $stat['nlink'] = 0;

        $stat['uid'] = 0;

        $stat['gid'] = 0;

        $stat['rdev'] = 0;

        $stat['size'] = 0;

        $stat['atime'] = 0;

        $stat['mtime'] = 0;

        $stat['ctime'] = 0;

        $stat['blksize'] = 0;

        $stat['blocks'] = 0;



    $name = $this->_getNamePart($path);

    if(($slash = strchr($name, '/')) === false || $slash == strlen($name)-1) {

        /* bucket */

        $stat['mode'] |= 040000;

    } else {

        $stat['mode'] |= 0100000;

    }

           $info = $this->_getS3Client($path)->getInfo($name);



        if (!empty($info)) {

            $stat['size']  = $info['size'];

            $stat['atime'] = time();

            $stat['mtime'] = $info['mtime'];

        }



        return $stat;

    }



    /**

     * Return the next filename in the directory

     *

     * @return string

     */

    public function dir_readdir()

    {

        $object = current($this->_bucketList);

        if ($object !== false) {

            next($this->_bucketList);

        }

        return $object;

    }



    /**

     * Reset the directory pointer

     *

     * @return boolean True

     */

    public function dir_rewinddir()

    {

        reset($this->_bucketList);

        return true;

    }



    /**

     * Close a directory

     *

     * @return boolean True

     */

    public function dir_closedir()

    {

        $this->_bucketList = array();

        return true;

    }

}