/institutions/european-election-results/lib/moriarty/graph.class.php

<?php

require_once dirname(__FILE__) . DIRECTORY_SEPARATOR . 'moriarty.inc.php';

require_once MORIARTY_ARC_DIR . "ARC2.php";

require_once MORIARTY_DIR . 'httprequest.class.php';

require_once MORIARTY_DIR . 'httprequestfactory.class.php';

require_once MORIARTY_DIR . 'simplegraph.class.php';

require_once MORIARTY_DIR . 'changeset.class.php';

/**

 * The base class for graphs in a store.

 */

class Graph {

  /**

   * @access private

   */

  var $uri;

  /**

   * @access private

   */

  var $credentials;

  /**

   * @access private

   */

  var $request_factory;



  /**

   * Create a new instance of this class

   * @param string uri URI of the graph

   * @param Credentials credentials the credentials to use for authenticated requests (optional)

   */

  function __construct($uri, $credentials = null, $request_factory = null)  {

    $this->uri = $uri;

    $this->credentials = $credentials;

    $this->request_factory = $request_factory;

  }



  /**

   * Apply a changeset to the graph

   * @param ChangeSet cs the changeset to apply

   * @return HttpResponse

   */

  function apply_changeset($cs) {

    return $this->apply_changeset_turtle( $cs->to_turtle());

  }



  /**

   * Apply a changeset in a versioned manner to the graph

   * @param ChangeSet cs the changeset to apply

   * @return HttpResponse

   */

  function apply_versioned_changeset($cs) {

    return $this->apply_versioned_changeset_rdfxml( $cs->to_rdfxml());

  }



    /**

   * Apply a changeset to the graph

   * @param string rdfxml the changeset to apply, serialised as RDF/XML

   * @return HttpResponse

   */

  function apply_changeset_turtle($turtle) {

    if (empty( $this->request_factory) ) {

      $this->request_factory = new HttpRequestFactory();

    }



    $uri = $this->uri;



    $request = $this->request_factory->make( 'POST', $uri, $this->credentials);

    $request->set_accept("*/*");

    $request->set_content_type("application/vnd.talis.changeset+turtle");

    $request->set_body( $turtle );



    return $request->execute();

  }



 





  /**

   * Apply a changeset to the graph

   * @param string rdfxml the changeset to apply, serialised as RDF/XML

   * @return HttpResponse

   */

  function apply_changeset_rdfxml($rdfxml) {

    if (empty( $this->request_factory) ) {

      $this->request_factory = new HttpRequestFactory();

    }



    $uri = $this->uri;



    $request = $this->request_factory->make( 'POST', $uri, $this->credentials);

    $request->set_accept("*/*");

    $request->set_content_type("application/vnd.talis.changeset+xml");

    $request->set_body( $rdfxml );



    return $request->execute();

  }



  /**

   * Apply a changeset in a versioned manner to the graph

   * @param string rdfxml the changeset to apply, serialised as RDF/XML

   * @return HttpResponse

   */

  function apply_versioned_changeset_rdfxml($rdfxml) {

    if (empty( $this->request_factory) ) {

      $this->request_factory = new HttpRequestFactory();

    }



    $uri = $this->uri . '/changesets';



    $request = $this->request_factory->make( 'POST', $uri, $this->credentials);

    $request->set_accept("*/*");

    $request->set_content_type("application/vnd.talis.changeset+xml");

    $request->set_body( $rdfxml );



    return $request->execute();

  }



  /**

   * Submit some RDF/XML to be added to the graph

   * @param string rdfxml the RDF to be submitted, serialised as RDF/XML

   * @return HttpResponse

   */

  function submit_rdfxml($rdfxml) {

    if (empty( $this->request_factory) ) {

      $this->request_factory = new HttpRequestFactory();

    }



    $uri = $this->uri;

    $request = $this->request_factory->make( 'POST', $uri, $this->credentials);

    $request->set_content_type("application/rdf+xml");

    $request->set_accept("*/*");

    $request->set_body( $rdfxml );

    return $request->execute();

  }





  /**

   * Submit some Turtle to be added to the graph

   * @param string turtle the RDF to be submitted, serialised as Turtle

   * @return HttpResponse

   */

  function submit_turtle($turtle, $gzip_encode=false) {

    if (empty( $this->request_factory) ) {

      $this->request_factory = new HttpRequestFactory();

    }

    $uri = $this->uri;

    $request = $this->request_factory->make( 'POST', $uri, $this->credentials);

    $request->set_content_type("text/turtle");

    $request->set_accept("*/*");

    $request->set_body( $turtle, $gzip_encode);

    return $request->execute();

  }



  function submit_ntriples_in_batches_from_file($filename,$no_of_lines=500, $callback=false) {

    $responses = array();

    $pointer = fopen($filename, 'r');

    $batch = '';

    $lineCount=0;

    while($line =  fgets($pointer)){

      $batch.=$line;

      $lineCount++;

      if($lineCount==$no_of_lines){

        $response = $this->submit_turtle($batch);

        $responses[] = $response;

        if(is_callable($callback)){

          call_user_func($callback, $response);

        } else if($response->is_success()===false){

          return $responses;

        } 



          $lineCount=0;

          $batch='';

        

      }

    }

    if(!empty($batch)){

      $response=$this->submit_turtle($batch);

      if(is_callable($callback)){

          call_user_func($callback, $response);

      } 

      $responses[]=$response;

    }

    return $responses;

  }



  /**

   * Obtain the graph's bounded description of a given resource

   * @see http://n2.talis.com/wiki/Metabox#Describing_a_Resource

   * @param string uri the URI of the resource to be described

   * @param string output the desired output format of the response (e.g. rdf, xml, json, ntriples, turtle)

   * @return HttpResponse

   */

  function describe( $uri, $output = null ) {



    $request = $this->get_describe_request($uri, $output);



    return $request->execute();

  }



  function get_describe_uri( $uri, $output = null ) {

    $request_uri = $this->uri . '?about=' . urlencode($uri);

    if ($output) {

      $request_uri .= '&output=' . urlencode($output);

    }

    return $request_uri;

  }

  function get_describe_request( $uri, $output = null ) {

    if (empty( $this->request_factory) ) {

      $this->request_factory = new HttpRequestFactory();

    }



    $request_uri = $this->get_describe_uri($uri, $output);

  

    $request = $this->request_factory->make( 'GET', $request_uri, $this->credentials);

    if ($output) {

      $request->set_accept("*/*");

    }

    else {

      $request->set_accept("application/rdf+xml");

    }

    $request->set_content_type("application/x-www-form-urlencoded");



    return $request;

  }



  /**

   * Obtain the graph's bounded description of a given resource

   * @deprecated triple lists are deprecated

   */

  function describe_to_triple_list( $uri ) {

    $triples = array();



    $response = $this->describe( $uri );

    $parser_args=array(

      "bnode_prefix"=>"genid",

      "base"=> $this->uri

    );

    $parser = ARC2::getRDFXMLParser($parser_args);



    if ( $response->body ) {

      $parser->parse($this->uri, $response->body );

      $triples = $parser->getTriples();

    }



    return $triples;

  }



  /**

   * Obtain the graph's bounded description of a given resource. This is designed to be fast since it uses RDF/JSON which requires no parsing by the SimpleGraph class. This method always returns a SimpleGraph, which will be empty if any HTTP errors occured.

   * @see http://n2.talis.com/wiki/Metabox#Describing_a_Resource

   * @param string uri the URI of the resource to be described

   * @return SimpleGraph

   */

  function describe_to_simple_graph( $uri ) {

    $graph = new SimpleGraph();



    $response = $this->describe( $uri, OUTPUT_TYPE_JSON );



    if ( $response->is_success() ) {

      $graph->from_json( $response->body );

    }



    return $graph;

  }



  /**

   * Tests whether the graph contains a bounded description of a given resource. This uses a conditional GET.

   * @see http://n2.talis.com/wiki/Metabox#Describing_a_Resource

   * @param string uri the URI of the resource to be described

   * @return boolean true if the graph contains triples with the resource as a subject, false otherwise

   */

  function has_description( $uri ) {

    if (empty( $this->request_factory) ) {

      $this->request_factory = new HttpRequestFactory();

    }



    $request_uri = $this->uri . '?about=' . urlencode($uri);

    $request = $this->request_factory->make( 'GET', $request_uri, $this->credentials);

    $request->set_accept("application/rdf+xml");

    $request->set_if_match("*");



    $response = $request->execute();



    if ($response->status_code == 200) {

      return true;

    }

    else if ($response->status_code == 412) {

      return false;

    }

  }



    /**

   * mirror_from_uri:

   *

   * @return array of responses from http requests, and overall success status 

   * @author Keith Alexander

   *

   *

  **/

  function mirror_from_uri($url, $rdf_content=false)

  {



      $return = array(

        'get_page' => false,

        'get_copy' => false,

        'update_data' => false,

        'success' => false,

      );



    if (empty( $this->request_factory) ) {

      $this->request_factory = new HttpRequestFactory();

    }

    



    if(!$rdf_content){

      

      $web_page_request  = $this->request_factory->make('GET', $url); 

      $web_page_request->set_accept('application/rdf+xml;q=0.8,text/turtle;q=0.9,*/*;q=0.1');

      $web_page_response = $web_page_request->execute();

      $return['get_page'] = $web_page_response;

      $web_page_content = $web_page_response->body;

    } else {

      $web_page_content = $rdf_content;

      $return['rdf_content'] = $rdf_content;

    }

    if($rdf_content OR $web_page_response->is_success() ){



    $newGraph = new SimpleGraph();

    $newGraph->add_rdf($web_page_content, $url);

    $jsonGraphContent = $newGraph->to_json();

    $newGraph->add_resource_triple($url, OPEN_JSON, $jsonGraphContent);

    $newGraph->skolemise_bnodes(trim($url,'#').'#');

    $after = $newGraph->get_index();

    # get previous copy if it exists

    $cached_page_response = $this->describe($url, 'json');

    $return['get_copy'] = $cached_page_response;

            if($cached_page_response->status_code == '200'){

              $description_index =  json_decode($cached_page_response->body, true);

              if(isset($description_index[$url]) AND isset($description_index[$url][OPEN_JSON])){

                $before = json_decode($description_index[$url][OPEN_JSON][0]['value'], 1);

              } else {

                $before = false;

              }

            } else if( $cached_page_response->status_code == '404' ) {

              $before = false;

            } else {

                return $return;

            }

    # build new changeset



    $Changeset = new ChangeSet(array('before' => $before, 'after' => $after, 'creatorName' => 'Graph::mirror_from_uri', 'changeReason' => 'mirroring from '.$url));



    if($Changeset->has_changes()){

      $return['update_data'] = $this->apply_changeset($Changeset);

      if($return['update_data']->is_success()){

        $return['success'] = true;

      } else if($return['update_data']->status_code=='409'){ # Conflict. some statements already removed.

        $before_graph = new SimpleGraph($before);

        $return['reapply_before_triples'] = $this->get_metabox()->submit_turtle($before_graph->to_turtle());

        if($return['reapply_before_triples']->status_code=='204'){ #Succeeded. No content

          $return['update_data'] = $this->get_metabox()->apply_changeset($Changeset);

          $return['success'] = $return['update_data']->is_success();

        }

      } else {

        return $return;

      } 

      return $return;

    } else {

       $return['success'] = true;

       return $return;

    }

    } else {

    

      return $return;

    }

  }









}

?>