You are here

abstract class MediaReadOnlyStreamWrapper in D7 Media 7

Same name and namespace in other branches
  1. 7.4 includes/MediaReadOnlyStreamWrapper.inc \MediaReadOnlyStreamWrapper
  2. 7.2 includes/MediaReadOnlyStreamWrapper.inc \MediaReadOnlyStreamWrapper
  3. 7.3 includes/MediaReadOnlyStreamWrapper.inc \MediaReadOnlyStreamWrapper

A base class for Resource Stream Wrappers.

This class provides a complete stream wrapper implementation. It passes incoming URL's through an interpolation method then recursively calls the invoking PHP filesystem function.

MediaReadOnlyStreamWrapper implementations need to override at least the interpolateUrl method to rewrite the URL before is it passed back into the calling function.

Hierarchy

Expanded class hierarchy of MediaReadOnlyStreamWrapper

File

includes/MediaReadOnlyStreamWrapper.inc, line 14

View source
abstract class MediaReadOnlyStreamWrapper implements DrupalStreamWrapperInterface {
  protected $parameters = array();
  protected $base_url = NULL;
  private $_DEBUG_MODE = NULL;
  public function get_parameters() {
    return $this->parameters;
  }

  // As part of the inode protection mode returned by stat(), identifies the
  // file as a regular file, as opposed to a directory, symbolic link, or other
  // type of "file".
  // @see http://linux.die.net/man/2/stat
  const S_IFREG = 0100000;

  /**
   * "Template" for stat calls. All elements must be initialized.
   * @var array
   */
  protected $_stat = array(
    0 => 0,
    // device number
    'dev' => 0,
    1 => 0,
    // inode number
    'ino' => 0,
    // inode protection mode. file_unmanaged_delete() requires is_file() to
    // return TRUE.
    2 => self::S_IFREG,
    'mode' => self::S_IFREG,
    3 => 0,
    // number of links
    'nlink' => 0,
    4 => 0,
    // userid of owner
    'uid' => 0,
    5 => 0,
    // groupid of owner
    'gid' => 0,
    6 => -1,
    // device type, if inode device *
    'rdev' => -1,
    7 => 0,
    // size in bytes
    'size' => 0,
    8 => 0,
    // time of last access (Unix timestamp)
    'atime' => 0,
    9 => 0,
    // time of last modification (Unix timestamp)
    'mtime' => 0,
    10 => 0,
    // time of last inode change (Unix timestamp)
    'ctime' => 0,
    11 => -1,
    // blocksize of filesystem IO
    'blksize' => -1,
    12 => -1,
    // number of blocks allocated
    'blocks' => -1,
  );
  function interpolateUrl() {
    if ($parameters = $this
      ->get_parameters()) {
      return $this->base_url . '?' . http_build_query($parameters);
    }
  }

  /**
   * Returns a web accessible URL for the resource.
   *
   * This function should return a URL that can be embedded in a web page
   * and accessed from a browser. For example, the external URL of
   * "youtube://xIpLd0WQKCY" might be
   * "http://www.youtube.com/watch?v=xIpLd0WQKCY".
   *
   * @return
   *   Returns a string containing a web accessible URL for the resource.
   */
  public function getExternalUrl() {
    return $this
      ->interpolateUrl();
  }

  /**
   * Base implementation of getMimeType().
   */
  static function getMimeType($uri, $mapping = NULL) {
    return 'application/octet-stream';
  }

  /**
   * Base implementation of realpath().
   */
  function realpath() {
    return $this
      ->getExternalUrl();
  }

  /**
   * Stream context resource.
   *
   * @var Resource
   */
  public $context;

  /**
   * A generic resource handle.
   *
   * @var Resource
   */
  public $handle = NULL;

  /**
   * Instance URI (stream).
   *
   * A stream is referenced as "scheme://target".
   *
   * @var String
   */
  protected $uri;

  /**
   * Base implementation of setUri().
   */
  function setUri($uri) {
    $this->uri = $uri;
    $this->parameters = $this
      ->_parse_url($uri);
  }

  /**
   * Base implementation of getUri().
   */
  function getUri() {
    return $this->uri;
  }

  /**
   *  Report an error.
   *  @param $message
   *    The untranslated string to report.
   *  @param $options
   *    An optional array of options to send to t().
   *  @param $display
   *    If TRUE, then we display the error to the user.
   *  @return
   *    We return FALSE, since we sometimes pass that back from the reporting
   *    function.
   */
  private function _report_error($message, $options = array(), $display = FALSE) {
    watchdog('resource', $message, $options, WATCHDOG_ERROR);
    if ($display) {
      drupal_set_message(t($message, $options), 'error');
    }
    return FALSE;
  }
  private function _debug($message, $type = 'status') {
    if ($this->_DEBUG_MODE) {
      drupal_set_message($message, $type);
    }
  }

  /**
   *  Returns an array of any parameters stored in the URL's path.
   *  @param $url
   *    The URL to parse, such as youtube://v/[video-code]/t/[tags+more-tags].
   *  @return
   *    An associative array of all the parameters in the path,
   *    or FALSE if the $url is ill-formed.
   */
  protected function _parse_url($url) {
    $path = explode('://', $url);
    $parts = explode('/', $path[1]);
    $params = array();
    $count = 0;
    $total = count($parts);
    if (!$total || $total % 2) {

      // If we have no parts, or an odd number of parts, it's malformed.
      return FALSE;
    }
    while ($count < $total) {

      // We iterate count for each step of the assignment to keep us honest.
      $params[$parts[$count++]] = $parts[$count++];
    }
    return $params;
  }

  /**
   * Support for fopen(), file_get_contents(), file_put_contents() etc.
   *
   * @param $path
   *   A string containing the path to the file to open.
   * @param $mode
   *   The file mode ("r", "wb" etc.).
   * @param $options
   *   A bit mask of STREAM_USE_PATH and STREAM_REPORT_ERRORS.
   * @param &$opened_path
   *   A string containing the path actually opened.
   * @return
   *  TRUE if file was opened successfully.
   */
  public function stream_open($url, $mode, $options, &$opened_url) {
    $this
      ->_debug(t('Stream open: %url', array(
      '%url' => $url,
    )));

    // We only handle Read-Only mode by default.
    if ($mode != 'r' && $mode != 'rb') {
      return $this
        ->_report_error('Attempted to open %url as mode: %mode.', array(
        '%url' => $url,
        '%mode' => $mode,
      ), $options & STREAM_REPORT_ERRORS);
    }

    // We parse a URL as youtube://v/dsyiufo34/t/cats+dogs to store
    // the relevant code(s) in our private array of parameters.
    $this->parameters = $this
      ->_parse_url($url);
    if ($this->parameters === FALSE) {
      return $this
        ->_report_error('Attempted to parse an ill-formed url: %url.', array(
        '%url' => $url,
      ), $options & STREAM_REPORT_ERRORS);
    }
    if ((bool) $this->parameters && $options & STREAM_USE_PATH) {
      $opened_url = $url;
    }
    $this
      ->_debug(t('Stream opened: %parameters', array(
      '%parameters' => print_r($this->parameters, TRUE),
    )));
    return (bool) $this->parameters;
  }

  // Undocumented PHP stream wrapper method.
  function stream_lock($operation) {
    return FALSE;
  }

  /**
   * Support for fread(), file_get_contents() etc.
   *
   * @param $count
   *    Maximum number of bytes to be read.
   * @return
   *  The string that was read, or FALSE in case of an error.
   */
  public function stream_read($count) {
    return FALSE;
  }

  /**
   * Support for fwrite(), file_put_contents() etc.
   *
   * @param $data
   *   The string to be written.
   * @return
   *   The number of bytes written.
   */
  public function stream_write($data) {
    return FALSE;
  }

  /**
   * Support for feof().
   *
   * @return
   *   TRUE if end-of-file has been reached.
   */
  public function stream_eof() {
    return FALSE;
  }

  /**
   * Support for fseek().
   *
   * @param $offset
   *   The byte offset to got to.
   * @param $whence
   *   SEEK_SET, SEEK_CUR, or SEEK_END.
   * @return
   *   TRUE on success
   */
  public function stream_seek($offset, $whence) {
    return FALSE;
  }

  /**
   * Support for fflush().
   *
   * @return
   *   TRUE if data was successfully stored (or there was no data to store).
   */
  public function stream_flush() {
    return FALSE;
  }

  /**
   * Support for ftell().
   *
   * @return
   *   The current offset in bytes from the beginning of file.
   */
  public function stream_tell() {
    return FALSE;
  }

  /**
   * Support for fstat().
   *
   * @return
   *   An array with file status, or FALSE in case of an error - see fstat()
   *   for a description of this array.
   */
  public function stream_stat() {
    return $this->_stat;
  }

  /**
   * Support for fclose().
   *
   * @return
   *   TRUE if stream was successfully closed.
   */
  public function stream_close() {
    return TRUE;
  }

  /**
   * Support for unlink().
   *
   * @param $uri
   *   A string containing the uri to the resource to delete.
   * @return
   *   TRUE if resource was successfully deleted.
   * @see http://php.net/manual/en/streamwrapper.unlink.php
   */

  //   public function unlink($uri) {
  //     $this->uri = $uri;
  //     return unlink($this->getLocalPath());
  //   }

  /**
   * Support for rename().
   *
   * @param $from_uri,
   *   The uri to the file to rename.
   * @param $to_uri
   *   The new uri for file.
   * @return
   *   TRUE if file was successfully renamed.
   * @see http://php.net/manual/en/streamwrapper.rename.php
   */

  //   public function rename($from_uri, $to_uri) {
  //     return rename($this->getLocalPath($from_uri), $this->getLocalPath($to_uri));
  //   }

  /**
   * Support for mkdir().
   *
   * @param $uri
   *   A string containing the URI to the directory to create.
   * @param $mode
   *   Permission flags - see mkdir().
   * @param $options
   *   A bit mask of STREAM_REPORT_ERRORS and STREAM_MKDIR_RECURSIVE.
   * @return
   *   TRUE if directory was successfully created.
   * @see http://php.net/manual/en/streamwrapper.mkdir.php
   */

  //   public function mkdir($uri, $mode, $options) {
  //     $this->uri = $uri;
  //     $recursive = (bool)($options & STREAM_MKDIR_RECURSIVE);
  //     if ($recursive) {
  //       // $this->getLocalPath() fails if $uri has multiple levels of directories
  //       // that do not yet exist.
  //       $localpath = $this->getDirectoryPath() . '/' . file_uri_target($uri);
  //     }
  //     else {
  //       $localpath = $this->getLocalPath($uri);
  //     }
  //     if ($options & STREAM_REPORT_ERRORS) {
  //       return mkdir($localpath, $mode, $recursive);
  //     }
  //     else {
  //       return @mkdir($localpath, $mode, $recursive);
  //     }
  //   }

  /**
   * Support for rmdir().
   *
   * @param $uri
   *   A string containing the URI to the directory to delete.
   * @param $options
   *   A bit mask of STREAM_REPORT_ERRORS.
   * @return
   *   TRUE if directory was successfully removed.
   * @see http://php.net/manual/en/streamwrapper.rmdir.php
   */

  //   public function rmdir($uri, $options) {
  //     $this->uri = $uri;
  //     if ($options & STREAM_REPORT_ERRORS) {
  //       return rmdir($this->getLocalPath());
  //     }
  //     else {
  //       return @rmdir($this->getLocalPath());
  //     }
  //   }

  /**
   * Support for stat().
   *
   * @param $url
   *   A string containing the url to get information about.
   * @param $flags
   *   A bit mask of STREAM_URL_STAT_LINK and STREAM_URL_STAT_QUIET.
   * @return
   *   An array with file status, or FALSE in case of an error - see fstat()
   *   for a description of this array.
   */
  public function url_stat($url, $flags) {
    return $this
      ->stream_stat();
  }

  /**
   * Support for opendir().
   *
   * @param $url
   *   A string containing the url to the directory to open.
   * @param $options
   *   Unknown (parameter is not documented in PHP Manual).
   * @return
   *   TRUE on success.
   */
  public function dir_opendir($url, $options) {
    return FALSE;
  }

  /**
   * Support for readdir().
   *
   * @return
   *   The next filename, or FALSE if there are no more files in the directory.
   */
  public function dir_readdir() {
    return FALSE;
  }

  /**
   * Support for rewinddir().
   *
   * @return
   *   TRUE on success.
   */
  public function dir_rewinddir() {
    return FALSE;
  }

  /**
   * Support for closedir().
   *
   * @return
   *   TRUE on success.
   */
  public function dir_closedir() {
    return FALSE;
  }
  public function getDirectoryPath() {
    return '';
  }

  /**
   * DrupalStreamWrapperInterface requires that these methods be implemented,
   * but none of them apply to a read-only stream wrapper. On failure they
   * are expected to return FALSE.
   */
  public function unlink($uri) {

    // Although the remote file itself can't be deleted, return TRUE so that
    // file_delete() can remove the file record from the database.
    return TRUE;
  }
  public function rename($from_uri, $to_uri) {
    return FALSE;
  }
  public function mkdir($uri, $mode, $options) {
    return FALSE;
  }
  public function rmdir($uri, $options) {
    return FALSE;
  }
  public function chmod($mode) {
    return FALSE;
  }
  public function dirname($uri = NULL) {
    return FALSE;
  }

}

Members

Namesort descending Modifiers Type Description Overrides
MediaReadOnlyStreamWrapper::$base_url protected property
MediaReadOnlyStreamWrapper::$context public property Stream context resource.
MediaReadOnlyStreamWrapper::$handle public property A generic resource handle.
MediaReadOnlyStreamWrapper::$parameters protected property
MediaReadOnlyStreamWrapper::$uri protected property Instance URI (stream).
MediaReadOnlyStreamWrapper::$_DEBUG_MODE private property
MediaReadOnlyStreamWrapper::$_stat protected property "Template" for stat calls. All elements must be initialized.
MediaReadOnlyStreamWrapper::chmod public function Changes permissions of the resource. Overrides DrupalStreamWrapperInterface::chmod
MediaReadOnlyStreamWrapper::dirname public function Gets the name of the directory from a given path. Overrides DrupalStreamWrapperInterface::dirname
MediaReadOnlyStreamWrapper::dir_closedir public function Support for closedir(). Overrides StreamWrapperInterface::dir_closedir
MediaReadOnlyStreamWrapper::dir_opendir public function Support for opendir(). Overrides StreamWrapperInterface::dir_opendir
MediaReadOnlyStreamWrapper::dir_readdir public function Support for readdir(). Overrides StreamWrapperInterface::dir_readdir
MediaReadOnlyStreamWrapper::dir_rewinddir public function Support for rewinddir(). Overrides StreamWrapperInterface::dir_rewinddir
MediaReadOnlyStreamWrapper::getDirectoryPath public function
MediaReadOnlyStreamWrapper::getExternalUrl public function Returns a web accessible URL for the resource. Overrides DrupalStreamWrapperInterface::getExternalUrl
MediaReadOnlyStreamWrapper::getMimeType static function Base implementation of getMimeType(). Overrides DrupalStreamWrapperInterface::getMimeType
MediaReadOnlyStreamWrapper::getUri function Base implementation of getUri(). Overrides DrupalStreamWrapperInterface::getUri
MediaReadOnlyStreamWrapper::get_parameters public function
MediaReadOnlyStreamWrapper::interpolateUrl function
MediaReadOnlyStreamWrapper::mkdir public function Overrides StreamWrapperInterface::mkdir
MediaReadOnlyStreamWrapper::realpath function Base implementation of realpath(). Overrides DrupalStreamWrapperInterface::realpath
MediaReadOnlyStreamWrapper::rename public function Overrides StreamWrapperInterface::rename
MediaReadOnlyStreamWrapper::rmdir public function Overrides StreamWrapperInterface::rmdir
MediaReadOnlyStreamWrapper::setUri function Base implementation of setUri(). Overrides DrupalStreamWrapperInterface::setUri
MediaReadOnlyStreamWrapper::stream_close public function Support for fclose(). Overrides StreamWrapperInterface::stream_close
MediaReadOnlyStreamWrapper::stream_eof public function Support for feof(). Overrides StreamWrapperInterface::stream_eof
MediaReadOnlyStreamWrapper::stream_flush public function Support for fflush(). Overrides StreamWrapperInterface::stream_flush
MediaReadOnlyStreamWrapper::stream_lock function Overrides StreamWrapperInterface::stream_lock
MediaReadOnlyStreamWrapper::stream_open public function Support for fopen(), file_get_contents(), file_put_contents() etc. Overrides StreamWrapperInterface::stream_open
MediaReadOnlyStreamWrapper::stream_read public function Support for fread(), file_get_contents() etc. Overrides StreamWrapperInterface::stream_read
MediaReadOnlyStreamWrapper::stream_seek public function Support for fseek(). Overrides StreamWrapperInterface::stream_seek
MediaReadOnlyStreamWrapper::stream_stat public function Support for fstat(). Overrides StreamWrapperInterface::stream_stat
MediaReadOnlyStreamWrapper::stream_tell public function Support for ftell(). Overrides StreamWrapperInterface::stream_tell
MediaReadOnlyStreamWrapper::stream_write public function Support for fwrite(), file_put_contents() etc. Overrides StreamWrapperInterface::stream_write
MediaReadOnlyStreamWrapper::S_IFREG constant
MediaReadOnlyStreamWrapper::unlink public function DrupalStreamWrapperInterface requires that these methods be implemented, but none of them apply to a read-only stream wrapper. On failure they are expected to return FALSE. Overrides StreamWrapperInterface::unlink
MediaReadOnlyStreamWrapper::url_stat public function Support for stat(). Overrides StreamWrapperInterface::url_stat
MediaReadOnlyStreamWrapper::_debug private function
MediaReadOnlyStreamWrapper::_parse_url protected function Returns an array of any parameters stored in the URL's path.
MediaReadOnlyStreamWrapper::_report_error private function Report an error.