class EasyRdf_Format

Class the represents an RDF file format.

For each format, the name, label, URIs and associated MIME Types are stored. A single parser and serialiser can also be registered to each format.

@package EasyRdf @copyright Copyright (c) 2009-2012 Nicholas J Humfrey @license http://www.opensource.org/licenses/bsd-license.php

Hierarchy

Expanded class hierarchy of EasyRdf_Format

1 string reference to 'EasyRdf_Format'
EasyRdf_Serialiser::checkSerialiseParams in drupal/core/vendor/easyrdf/easyrdf/lib/EasyRdf/Serialiser.php
Check and cleanup parameters passed to serialise() method @ignore

File

drupal/core/vendor/easyrdf/easyrdf/lib/EasyRdf/Format.php, line 50

View source
class EasyRdf_Format {
  private static $formats = array();
  private $name = array();
  private $label = null;
  private $uri = null;
  private $mimeTypes = array();
  private $extensions = array();
  private $parserClass = null;
  private $serialiserClass = null;

  /** Get a list of format names
   *
   * @return array          An array of formats name
   */
  public static function getNames() {
    return array_keys(self::$formats);
  }

  /** Get a list of all the registered formats
   *
   * @return array          An array of format objects
   */
  public static function getFormats() {
    return self::$formats;
  }

  /** Generates an HTTP Accept header string
   *
   * The string will contain all of the MIME Types that we
   * are able to parse.
   *
   * It is also possible to specify additional MIME types
   * in the form array('text/plain' => 0.5) where 0.5 is the
   * q value for that type. The types are sorted by q value
   * before constructing the string.
   *
   * @param array $extraTypes    extra MIME types to add
   * @return string              list of supported MIME types
   */
  public static function getHttpAcceptHeader($extraTypes = array()) {
    $accept = $extraTypes;
    foreach (self::$formats as $format) {
      if ($format->parserClass and count($format->mimeTypes) > 0) {
        $accept = array_merge($accept, $format->mimeTypes);
      }
    }
    arsort($accept, SORT_NUMERIC);
    $acceptStr = '';
    foreach ($accept as $type => $q) {
      if ($acceptStr) {
        $acceptStr .= ',';
      }
      if ($q == 1.0) {
        $acceptStr .= $type;
      }
      else {
        $acceptStr .= sprintf("%s;q=%1.1f", $type, $q);
      }
    }
    return $acceptStr;
  }

  /** Check if a named graph exists
   *
   * @param string $name    the name of the format
   * @return boolean        true if the format exists
   */
  public static function formatExists($name) {
    return array_key_exists($name, self::$formats);
  }

  /** Get a EasyRdf_Format from a name, uri or mime type
   *
   * @param string $query   a query string to search for
   * @return object         the first EasyRdf_Format that matches the query
   * @throws EasyRdf_Exception  if no format is found
   */
  public static function getFormat($query) {
    if (!is_string($query) or $query == null or $query == '') {
      throw new InvalidArgumentException("\$query should be a string and cannot be null or empty");
    }
    foreach (self::$formats as $format) {
      if ($query == $format->name or $query == $format->uri or array_key_exists($query, $format->mimeTypes) or in_array($query, $format->extensions)) {
        return $format;
      }
    }

    # No match
    throw new EasyRdf_Exception("Format is not recognised: {$query}");
  }

  /** Register a new format
   *
   * @param  string  $name       The name of the format (e.g. ntriples)
   * @param  string  $label      The label for the format (e.g. N-Triples)
   * @param  string  $uri        The URI for the format
   * @param  string  $mimeTypes  One or more mime types for the format
   * @param  string  $extensions One or more extensions (file suffix)
   * @return object              The new EasyRdf_Format object
   */
  public static function register($name, $label = null, $uri = null, $mimeTypes = array(), $extensions = array()) {
    if (!is_string($name) or $name == null or $name == '') {
      throw new InvalidArgumentException("\$name should be a string and cannot be null or empty");
    }
    if (!array_key_exists($name, self::$formats)) {
      self::$formats[$name] = new EasyRdf_Format($name);
    }
    self::$formats[$name]
      ->setLabel($label);
    self::$formats[$name]
      ->setUri($uri);
    self::$formats[$name]
      ->setMimeTypes($mimeTypes);
    self::$formats[$name]
      ->setExtensions($extensions);
    return self::$formats[$name];
  }

  /** Remove a format from the registry
   *
   * @param  string  $name      The name of the format (e.g. ntriples)
   */
  public static function unregister($name) {
    unset(self::$formats[$name]);
  }

  /** Class method to register a parser class to a format name
   *
   * @param  string  $name   The name of the format (e.g. ntriples)
   * @param  string  $class  The name of the class (e.g. EasyRdf_Parser_Ntriples)
   */
  public static function registerParser($name, $class) {
    if (!self::formatExists($name)) {
      self::register($name);
    }
    self::getFormat($name)
      ->setParserClass($class);
  }

  /** Class method to register a serialiser class to a format name
   *
   * @param  string  $name   The name of the format (e.g. ntriples)
   * @param  string  $class  The name of the class (e.g. EasyRdf_Serialiser_Ntriples)
   */
  public static function registerSerialiser($name, $class) {
    if (!self::formatExists($name)) {
      self::register($name);
    }
    self::getFormat($name)
      ->setSerialiserClass($class);
  }

  /** Attempt to guess the document format from some content.
   *
   * If $filename is given, then the suffix is first used to guess the format.
   *
   * If the document format is not recognised, null is returned.
   *
   * @param  string $data     The document data
   * @param  string $filename Optional filename
   * @return object EasyRdf_Format The format object
   */
  public static function guessFormat($data, $filename = null) {
    if (is_array($data)) {

      # Data has already been parsed into RDF/PHP
      return self::getFormat('php');
    }

    // First try and identify by the filename
    if ($filename and preg_match("/\\.(\\w+)\$/", $filename, $matches)) {
      foreach (self::$formats as $format) {
        if (in_array($matches[1], $format->extensions)) {
          return $format;
        }
      }
    }

    // Then try and guess by the first 255 bytes of content
    $short = substr($data, 0, 255);
    if (preg_match("/^\\s*\\{/", $short)) {
      return self::getFormat('json');
    }
    elseif (preg_match("/<rdf:/i", $short)) {
      return self::getFormat('rdfxml');
    }
    elseif (preg_match("/@prefix\\s|@base\\s/", $short)) {
      return self::getFormat('turtle');
    }
    elseif (preg_match("/^\\s*<.+> <.+>/m", $short)) {
      return self::getFormat('ntriples');
    }
    elseif (preg_match("|http://www.w3.org/2005/sparql-results|", $short)) {
      return self::getFormat('sparql-xml');
    }
    elseif (preg_match("/\\WRDFa\\W/i", $short)) {
      return self::getFormat('rdfa');
    }
    elseif (preg_match("/<!DOCTYPE html|<html/i", $short)) {

      # We don't support any other microformats embedded in HTML
      return self::getFormat('rdfa');
    }
    else {
      return null;
    }
  }

  /**
   * This constructor is for internal use only.
   * To create a new format, use the register method.
   *
   * @param  string  $name    The name of the format
   * @see    EasyRdf_Format::register()
   * @ignore
   */
  public function __construct($name) {
    $this->name = $name;
    $this->label = $name;

    # Only a default
  }

  /** Get the name of a format object
   *
   * @return string The name of the format (e.g. rdfxml)
   */
  public function getName() {
    return $this->name;
  }

  /** Get the label for a format object
   *
   * @return string The format label (e.g. RDF/XML)
   */
  public function getLabel() {
    return $this->label;
  }

  /** Set the label for a format object
   *
   * @param  string $label  The new label for the format
   */
  public function setLabel($label) {
    if ($label) {
      if (!is_string($label)) {
        throw new InvalidArgumentException("\$label should be a string");
      }
      return $this->label = $label;
    }
    else {
      return $this->label = null;
    }
  }

  /** Get the URI for a format object
   *
   * @return string The format URI
   */
  public function getUri() {
    return $this->uri;
  }

  /** Set the URI for a format object
   *
   * @param string $uri  The new URI for the format
   */
  public function setUri($uri) {
    if ($uri) {
      if (!is_string($uri)) {
        throw new InvalidArgumentException("\$uri should be a string");
      }
      return $this->uri = $uri;
    }
    else {
      return $this->uri = null;
    }
  }

  /** Get the default registered mime type for a format object
   *
   * @return string The default mime type as a string.
   */
  public function getDefaultMimeType() {
    $types = array_keys($this->mimeTypes);
    return $types[0];
  }

  /** Get all the registered mime types for a format object
   *
   * @return array One or more MIME types in an array with
   *               the mime type as the key and q value as the value
   */
  public function getMimeTypes() {
    return $this->mimeTypes;
  }

  /** Set the MIME Types for a format object
   *
   * @param array $mimeTypes  One or more mime types
   */
  public function setMimeTypes($mimeTypes) {
    if ($mimeTypes) {
      if (!is_array($mimeTypes)) {
        $mimeTypes = array(
          $mimeTypes,
        );
      }
      $this->mimeTypes = $mimeTypes;
    }
    else {
      $this->mimeTypes = array();
    }
  }

  /** Get the default registered file extension (filename suffix) for a format object
   *
   * @return string The default extension as a string.
   */
  public function getDefaultExtension() {
    return $this->extensions[0];
  }

  /** Get all the registered file extensions (filename suffix) for a format object
   *
   * @return array One or more extensions as an array
   */
  public function getExtensions() {
    return $this->extensions;
  }

  /** Set the file format extensions (filename suffix) for a format object
   *
   * @param mixed $extensions  One or more file extensions
   */
  public function setExtensions($extensions) {
    if ($extensions) {
      if (!is_array($extensions)) {
        $extensions = array(
          $extensions,
        );
      }
      $this->extensions = $extensions;
    }
    else {
      $this->extensions = array();
    }
  }

  /** Set the parser to use for a format
   *
   * @param string $class  The name of the class
   */
  public function setParserClass($class) {
    if ($class) {
      if (!is_string($class)) {
        throw new InvalidArgumentException("\$class should be a string");
      }
      $this->parserClass = $class;
    }
    else {
      $this->parserClass = null;
    }
  }

  /** Get the name of the class to use to parse the format
   *
   * @return string The name of the class
   */
  public function getParserClass() {
    return $this->parserClass;
  }

  /** Create a new parser to parse this format
   *
   * @return object The new parser object
   */
  public function newParser() {
    $parserClass = $this->parserClass;
    if (!$parserClass) {
      throw new EasyRdf_Exception("No parser class available for format: " . $this
        ->getName());
    }
    return new $parserClass();
  }

  /** Set the serialiser to use for a format
   *
   * @param string $class  The name of the class
   */
  public function setSerialiserClass($class) {
    if ($class) {
      if (!is_string($class)) {
        throw new InvalidArgumentException("\$class should be a string");
      }
      $this->serialiserClass = $class;
    }
    else {
      $this->serialiserClass = null;
    }
  }

  /** Get the name of the class to use to serialise the format
   *
   * @return string The name of the class
   */
  public function getSerialiserClass() {
    return $this->serialiserClass;
  }

  /** Create a new serialiser to parse this format
   *
   * @return object The new serialiser object
   */
  public function newSerialiser() {
    $serialiserClass = $this->serialiserClass;
    if (!$serialiserClass) {
      throw new EasyRdf_Exception("No serialiser class available for format: " . $this
        ->getName());
    }
    return new $serialiserClass();
  }

  /** Magic method to return the name of the format when casted to string
   *
   * @return string The name of the format
   */
  public function __toString() {
    return $this->name;
  }

}

Members

Namesort descending Modifiers Type Description Overrides
EasyRdf_Format::$extensions private property
EasyRdf_Format::$formats private static property
EasyRdf_Format::$label private property
EasyRdf_Format::$mimeTypes private property
EasyRdf_Format::$name private property
EasyRdf_Format::$parserClass private property
EasyRdf_Format::$serialiserClass private property
EasyRdf_Format::$uri private property
EasyRdf_Format::formatExists public static function Check if a named graph exists
EasyRdf_Format::getDefaultExtension public function Get the default registered file extension (filename suffix) for a format object
EasyRdf_Format::getDefaultMimeType public function Get the default registered mime type for a format object
EasyRdf_Format::getExtensions public function Get all the registered file extensions (filename suffix) for a format object
EasyRdf_Format::getFormat public static function Get a EasyRdf_Format from a name, uri or mime type
EasyRdf_Format::getFormats public static function Get a list of all the registered formats
EasyRdf_Format::getHttpAcceptHeader public static function Generates an HTTP Accept header string
EasyRdf_Format::getLabel public function Get the label for a format object
EasyRdf_Format::getMimeTypes public function Get all the registered mime types for a format object
EasyRdf_Format::getName public function Get the name of a format object
EasyRdf_Format::getNames public static function Get a list of format names
EasyRdf_Format::getParserClass public function Get the name of the class to use to parse the format
EasyRdf_Format::getSerialiserClass public function Get the name of the class to use to serialise the format
EasyRdf_Format::getUri public function Get the URI for a format object
EasyRdf_Format::guessFormat public static function Attempt to guess the document format from some content.
EasyRdf_Format::newParser public function Create a new parser to parse this format
EasyRdf_Format::newSerialiser public function Create a new serialiser to parse this format
EasyRdf_Format::register public static function Register a new format
EasyRdf_Format::registerParser public static function Class method to register a parser class to a format name
EasyRdf_Format::registerSerialiser public static function Class method to register a serialiser class to a format name
EasyRdf_Format::setExtensions public function Set the file format extensions (filename suffix) for a format object
EasyRdf_Format::setLabel public function Set the label for a format object
EasyRdf_Format::setMimeTypes public function Set the MIME Types for a format object
EasyRdf_Format::setParserClass public function Set the parser to use for a format
EasyRdf_Format::setSerialiserClass public function Set the serialiser to use for a format
EasyRdf_Format::setUri public function Set the URI for a format object
EasyRdf_Format::unregister public static function Remove a format from the registry
EasyRdf_Format::__construct public function This constructor is for internal use only. To create a new format, use the register method.
EasyRdf_Format::__toString public function Magic method to return the name of the format when casted to string