vendor/wikimedia/purtle/src/TurtleRdfWriter.php

   1 <?php
   2
   3 namespace Wikimedia\Purtle;
   4
   5 /**
   6  * RdfWriter implementation for generating Turtle output.
   7  *
   8  * @license GPL-2.0+
   9  * @author Daniel Kinzler
  10  */
  11 class TurtleRdfWriter extends N3RdfWriterBase {
  12         /**
  13          * @var bool
  14          */
  15         private $trustIRIs = true;
  16
  17         /**
  18          * @return bool
  19          */
  20         public function getTrustIRIs() {
  21                 return $this->trustIRIs;
  22         }
  23
  24         /**
  25          * @param bool $trustIRIs
  26          */
  27         public function setTrustIRIs( $trustIRIs ) {
  28                 $this->trustIRIs = $trustIRIs;
  29         }
  30
  31         public function __construct(
  32                 $role = parent::DOCUMENT_ROLE,
  33                 BNodeLabeler $labeler = null,
  34                 N3Quoter $quoter = null
  35         ) {
  36                 parent::__construct( $role, $labeler, $quoter );
  37                 $this->transitionTable[self::STATE_OBJECT] = [
  38                         self::STATE_DOCUMENT => " .\n",
  39                         self::STATE_SUBJECT => " .\n\n",
  40                         self::STATE_PREDICATE => " ;\n\t",
  41                         self::STATE_OBJECT => ",\n\t\t",
  42                 ];
  43                 $this->transitionTable[self::STATE_DOCUMENT][self::STATE_SUBJECT] = "\n";
  44                 $this->transitionTable[self::STATE_SUBJECT][self::STATE_PREDICATE] = ' ';
  45                 $this->transitionTable[self::STATE_PREDICATE][self::STATE_OBJECT] = ' ';
  46                 $this->transitionTable[self::STATE_START][self::STATE_DOCUMENT] = function () {
  47                         $this->beginDocument();
  48                 };
  49         }
  50
  51         /**
  52          * Write prefixes
  53          */
  54         private function beginDocument() {
  55                 foreach ( $this->getPrefixes() as $prefix => $uri ) {
  56                         $this->write( "@prefix $prefix: <" . $this->quoter->escapeIRI( $uri ) . "> .\n" );
  57                 }
  58         }
  59
  60         protected function writeSubject( $base, $local = null ) {
  61                 if ( $local !== null ) {
  62                         $this->write( "$base:$local" );
  63                 } else {
  64                         $this->writeIRI( $base, $this->trustIRIs );
  65                 }
  66         }
  67
  68         protected function writePredicate( $base, $local = null ) {
  69                 if ( $base === 'a' ) {
  70                         $this->write( 'a' );
  71                         return;
  72                 }
  73                 if ( $local !== null ) {
  74                         $this->write( "$base:$local" );
  75                 } else {
  76                         $this->writeIRI( $base, $this->trustIRIs );
  77                 }
  78         }
  79
  80         protected function writeResource( $base, $local = null ) {
  81                 if ( $local !== null ) {
  82                         $this->write( "$base:$local" );
  83                 } else {
  84                         $this->writeIRI( $base );
  85                 }
  86         }
  87
  88         /**
  89          * @param string $role
  90          * @param BNodeLabeler $labeler
  91          *
  92          * @return RdfWriterBase
  93          */
  94         protected function newSubWriter( $role, BNodeLabeler $labeler ) {
  95                 $writer = new self( $role, $labeler, $this->quoter );
  96
  97                 return $writer;
  98         }
  99
 100         /**
 101          * @return string a MIME type
 102          */
 103         public function getMimeType() {
 104                 return 'text/turtle; charset=UTF-8';
 105         }
 106
 107 }