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Implemented RSS feed support for extended datetime literals that include CCK datetime fields' time zone names.
| 1 | <?php |
| 2 | // $Id: rdf.api.inc,v 1.39 2009/07/10 14:40:08 arto Exp $ |
| 3 | |
| 4 | ////////////////////////////////////////////////////////////////////////////// |
| 5 | // RDF API settings |
| 6 | |
| 7 | define('RDF_ARC2_PATH', drupal_get_path('module', 'rdf') . '/vendor/arc'); |
| 8 | define('RDF_FORMAT', variable_get('rdf_format', 'rdf+json')); |
| 9 | define('RDF_FORMAT_RSS', variable_get('rdf_format_rss', 'rdf+xml')); |
| 10 | define('RDF_SITE_URI', url(NULL, array('absolute' => TRUE))); |
| 11 | |
| 12 | ////////////////////////////////////////////////////////////////////////////// |
| 13 | // RDF API repository selection |
| 14 | |
| 15 | /** |
| 16 | * Limits future queries and operations to a particular repository. |
| 17 | */ |
| 18 | function rdf_use_repository($name = NULL) { |
| 19 | if (is_null($name)) { |
| 20 | unset($GLOBALS['rdf_repository']); |
| 21 | } |
| 22 | else { |
| 23 | $GLOBALS['rdf_repository'] = $name; |
| 24 | } |
| 25 | } |
| 26 | |
| 27 | ////////////////////////////////////////////////////////////////////////////// |
| 28 | // RDF API namespace support |
| 29 | |
| 30 | function rdf_define_vocabularies() { |
| 31 | $properties = rdf_rdf_properties(); |
| 32 | foreach (rdf_rdf_namespaces() as $prefix => $base_uri) { |
| 33 | if (isset($properties[$prefix])) { |
| 34 | rdf_define_vocabulary($prefix, $base_uri, $properties[$prefix]); |
| 35 | } |
| 36 | } |
| 37 | } |
| 38 | |
| 39 | /** |
| 40 | * Defines an RDF namespace class for predicate URI construction based on a |
| 41 | * given base URI and a set of properties. |
| 42 | */ |
| 43 | function rdf_define_vocabulary($class_name, $base_uri, array $properties) { |
| 44 | if (!class_exists('RDF_Namespace')) { |
| 45 | eval('abstract class RDF_Namespace {}'); |
| 46 | } |
| 47 | |
| 48 | $code = array(); |
| 49 | $code[] = "abstract class $class_name extends RDF_Namespace {"; |
| 50 | foreach ($properties as $property) { |
| 51 | $code[] = "\tconst $property = '{$base_uri}{$property}';"; |
| 52 | } |
| 53 | $code[] = "static function uriref(\$property) { return rdf_uri('{$base_uri}' . \$property); }"; |
| 54 | $code[] = '}'; |
| 55 | return eval(implode("\n", $code)); |
| 56 | } |
| 57 | |
| 58 | ////////////////////////////////////////////////////////////////////////////// |
| 59 | // RDF API statement-centric queries |
| 60 | |
| 61 | /** |
| 62 | * Determines whether a given statement exists. |
| 63 | * |
| 64 | * @param $subject |
| 65 | * @param $predicate |
| 66 | * @param $object |
| 67 | * @param $options |
| 68 | * @return |
| 69 | * TRUE if the statement exists, FALSE otherwise. |
| 70 | */ |
| 71 | function rdf_exists($subject, $predicate = NULL, $object = NULL, array $options = array()) { |
| 72 | return rdf_count($subject, $predicate, $object, $options) > 0; |
| 73 | } |
| 74 | |
| 75 | /** |
| 76 | * Returns the number of matching statements. |
| 77 | * |
| 78 | * @param $subject |
| 79 | * @param $predicate |
| 80 | * @param $object |
| 81 | * @param $options |
| 82 | * @return |
| 83 | */ |
| 84 | function rdf_count($subject = NULL, $predicate = NULL, $object = NULL, array $options = array()) { |
| 85 | $results = rdf_query($subject, $predicate, $object, $options); |
| 86 | return count(is_object($results) ? $results->to_array() : $results); |
| 87 | } |
| 88 | |
| 89 | /** |
| 90 | * @param $subject |
| 91 | * @param $predicate |
| 92 | * @param $default |
| 93 | * @param $options |
| 94 | */ |
| 95 | function rdf_value($subject, $predicate, $default = NULL, array $options = array()) { |
| 96 | foreach (rdf_query($subject, $predicate, NULL, $options) as $statement) { |
| 97 | return $statement[2]; // object |
| 98 | } |
| 99 | return $default; |
| 100 | } |
| 101 | |
| 102 | /** |
| 103 | * Finds all statements matching a given triple pattern. |
| 104 | * |
| 105 | * @param $subject |
| 106 | * @param $predicate |
| 107 | * @param $object |
| 108 | * @param $options |
| 109 | * @return |
| 110 | * An instance of RDF_QueryIterator, yielding denormalized statements. |
| 111 | */ |
| 112 | function rdf_query($subject = NULL, $predicate = NULL, $object = NULL, array $options = array()) { |
| 113 | $subject = $subject ? _rdf_query_arg($subject) : $subject; |
| 114 | $predicate = $predicate ? _rdf_query_arg($predicate) : $predicate; |
| 115 | $repos = isset($options['repository']) ? $options['repository'] : NULL; |
| 116 | |
| 117 | $results = new RDF_QueryIterator(); |
| 118 | foreach (_rdf_get_callbacks('query', $repos) as $callback) { |
| 119 | list($callable, $callable_args) = $callback; |
| 120 | $args = array($subject, $predicate, $object, $options); |
| 121 | $args = !is_array($callable_args) ? $args : array_merge($callable_args, $args); |
| 122 | $results->append(new IteratorIterator(new RDF_QueryCallback($callable, $args))); |
| 123 | } |
| 124 | return $results; |
| 125 | } |
| 126 | |
| 127 | ////////////////////////////////////////////////////////////////////////////// |
| 128 | // RDF API statement-centric operations |
| 129 | |
| 130 | /** |
| 131 | * Inserts multiple new statements. |
| 132 | * |
| 133 | * @param $statements |
| 134 | * @return |
| 135 | * TRUE if all statements were successfully inserted, FALSE otherwise. |
| 136 | */ |
| 137 | function rdf_insert_all($statements, array $options = array()) { |
| 138 | $result = TRUE; |
| 139 | foreach ($statements as $statement) { |
| 140 | $result = call_user_func_array('rdf_insert', array_merge($statement, array($options))) && $result; |
| 141 | } |
| 142 | return $result; |
| 143 | } |
| 144 | |
| 145 | /** |
| 146 | * Inserts a new statement. |
| 147 | * |
| 148 | * @param $subject |
| 149 | * @param $predicate |
| 150 | * @param $object |
| 151 | * @param $options |
| 152 | * @return |
| 153 | * TRUE, or a repository-specific non-NULL value, if the statement was |
| 154 | * successfully inserted; FALSE if an error occurred. |
| 155 | */ |
| 156 | function rdf_insert($subject, $predicate, $object, array $options = array()) { |
| 157 | $subject = $subject ? _rdf_query_arg($subject) : $subject; |
| 158 | $predicate = $predicate ? _rdf_query_arg($predicate) : $predicate; |
| 159 | $repos = isset($options['repository']) ? $options['repository'] : NULL; |
| 160 | |
| 161 | return _rdf_invoke_op('insert', array($subject, $predicate, $object, $options), $repos); |
| 162 | } |
| 163 | |
| 164 | /** |
| 165 | * Deletes an existing statement. |
| 166 | * |
| 167 | * @param $subject |
| 168 | * @param $predicate |
| 169 | * @param $object |
| 170 | * @param $options |
| 171 | * @return |
| 172 | * TRUE, or a repository-specific non-NULL value, if the statement was |
| 173 | * successfully deleted; FALSE if an error occurred. |
| 174 | */ |
| 175 | function rdf_delete($subject, $predicate, $object, array $options = array()) { |
| 176 | $subject = $subject ? _rdf_query_arg($subject) : $subject; |
| 177 | $predicate = $predicate ? _rdf_query_arg($predicate) : $predicate; |
| 178 | $repos = isset($options['repository']) ? $options['repository'] : NULL; |
| 179 | |
| 180 | return _rdf_invoke_op('delete', array($subject, $predicate, $object, $options), $repos); |
| 181 | } |
| 182 | |
| 183 | ////////////////////////////////////////////////////////////////////////////// |
| 184 | // RDF API data constructors |
| 185 | |
| 186 | function rdf_triple($subject, $predicate, $object) { |
| 187 | return func_get_args(); |
| 188 | } |
| 189 | |
| 190 | function rdf_mailto($email) { |
| 191 | return rdf_uri('mailto:' . $email); |
| 192 | } |
| 193 | |
| 194 | function rdf_uri($uri) { |
| 195 | return RDF_URIRef::uri($uri); |
| 196 | } |
| 197 | |
| 198 | function rdf_uriref($uri) { return rdf_uri($uri); } /* deprecated */ |
| 199 | function r($uri) { return rdf_uri($uri); } |
| 200 | |
| 201 | function rdf_bnode($id = NULL) { |
| 202 | return $id ? RDF_BNode::id($id) : RDF_BNode::generate(); |
| 203 | } |
| 204 | |
| 205 | function rdf_datetime($timestamp = NULL, $tz_offset = NULL, $tz_name = NULL, $datatype = 'xsd:dateTime') { |
| 206 | if (is_numeric($timestamp)) { |
| 207 | $timestamp = (int)$timestamp; |
| 208 | } |
| 209 | else if (is_string($timestamp)) { |
| 210 | $timestamp = strtotime($timestamp); |
| 211 | } |
| 212 | else if (is_null($timestamp)) { |
| 213 | $timestamp = gmmktime(); |
| 214 | } |
| 215 | |
| 216 | $datetime = format_date($timestamp, 'custom', 'Y-m-d\TH:i:sO', (int)$tz_offset); |
| 217 | $datetime = str_replace('+0000', 'Z', $datetime); // clean up format_date() result |
| 218 | $datetime = preg_replace('/([+-])(\d{2}):?(\d{2})$/', '\1\2:\3', $datetime); |
| 219 | |
| 220 | // This is a non-standard extension for outputting the time zone name |
| 221 | // appended to the datetime literal value. If you don't know why you'd do |
| 222 | // this, then you don't need this. However, if you *do* need this, make |
| 223 | // sure to also specify another literal datatype than 'xsd:dateTime' in |
| 224 | // the $datatype argument in order to avoid overloading the XSD semantics. |
| 225 | // Example output: "2009-08-15T23:59:59-04:00 America/New_York"^^$datatype |
| 226 | if ($tz_name) { |
| 227 | $datetime .= ' ' . (string)$tz_name; |
| 228 | } |
| 229 | |
| 230 | return rdf_literal($datetime, NULL, $datatype); |
| 231 | } |
| 232 | |
| 233 | function rdf_literal($value, $language = NULL, $datatype = NULL) { |
| 234 | $language = is_object($language) && isset($language->language) ? $language->language : $language; |
| 235 | $language = ($language === TRUE) ? $GLOBALS['language']->language : $language; // for convenience |
| 236 | return empty($language) && empty($datatype) ? $value : new RDF_Literal($value, $language, $datatype); |
| 237 | } |
| 238 | |
| 239 | function rdf_var($name) { |
| 240 | return new RDF_Variable($name); |
| 241 | } |
| 242 | |
| 243 | function rdf_is_var($value) { |
| 244 | return is_object($value) && ($value instanceof RDF_Variable); |
| 245 | } |
| 246 | |
| 247 | function rdf_seq() { |
| 248 | return new RDF_Seq(func_get_args()); |
| 249 | } |
| 250 | |
| 251 | function rdf_bag() { |
| 252 | return new RDF_Bag(func_get_args()); |
| 253 | } |
| 254 | |
| 255 | function rdf_alt() { |
| 256 | return new RDF_Alt(func_get_args()); |
| 257 | } |
| 258 | |
| 259 | function rdf_val_to_str($value) { |
| 260 | return (is_object($value) && $value instanceof RDF_Literal) ? $value->value : (string)$value; |
| 261 | } |
| 262 | |
| 263 | function rdf_str_to_val($string) { |
| 264 | $value = $string; |
| 265 | |
| 266 | // Attempt to cast untyped values to the correct RDF datatypes: |
| 267 | if (is_string($string)) { |
| 268 | if (rdf_is_valid_uri($string)) { // rdf:resource |
| 269 | $value = rdf_uri($string); |
| 270 | } |
| 271 | else if (rdf_is_valid_datetime($string)) { // xsd:dateTime |
| 272 | $tz = date_default_timezone_get(); |
| 273 | date_default_timezone_set('UTC'); |
| 274 | $value = rdf_datetime(strtotime($string)); |
| 275 | date_default_timezone_set($tz); |
| 276 | } |
| 277 | else if (is_numeric($string)) { // xsd:numeric |
| 278 | // TODO: should we cast to numeric types? this can be ambiguous... |
| 279 | } |
| 280 | } |
| 281 | |
| 282 | return $value; |
| 283 | } |
| 284 | |
| 285 | ////////////////////////////////////////////////////////////////////////////// |
| 286 | // RDF API helper functions |
| 287 | |
| 288 | function rdf_is_local_uri($uri) { |
| 289 | $base_uri = $GLOBALS['base_url'] . '/'; // FIXME? |
| 290 | return (strpos($uri, $base_uri) === 0) ? substr($uri, strlen($base_uri)) : FALSE; |
| 291 | } |
| 292 | |
| 293 | function rdf_is_valid_uri($uri) { |
| 294 | return rdf_is_valid_url($uri) || rdf_is_valid_urn($uri); |
| 295 | } |
| 296 | |
| 297 | function rdf_is_valid_url($url) { |
| 298 | static $allowed_characters = '[a-z0-9\/:_\-_\.\?\$,;~=#&%\+]'; |
| 299 | return preg_match("/^([a-z]+):\/\/" . $allowed_characters . "+$/i", (string)$url); |
| 300 | } |
| 301 | |
| 302 | function rdf_is_valid_urn($urn) { |
| 303 | return preg_match('/^urn:/', $urn) || preg_match('/^mailto:/', $urn); // FIXME |
| 304 | } |
| 305 | |
| 306 | function rdf_is_valid_curie($curie) { |
| 307 | return preg_match('/^\[?[\w\-]+:[\w\-]*\]?$/', (string)$curie); // FIXME |
| 308 | } |
| 309 | |
| 310 | function rdf_is_valid_qname($qname) { |
| 311 | return preg_match('/^[\w\-]+:[\w\-]+$/', (string)$qname); // FIXME |
| 312 | } |
| 313 | |
| 314 | function rdf_is_valid_prefix($qname) { |
| 315 | $namespaces = rdf_get_namespaces(); |
| 316 | list($prefix,) = explode(':', $qname, 2); |
| 317 | return isset($namespaces[$prefix]); |
| 318 | } |
| 319 | |
| 320 | function rdf_is_valid_datetime($string) { |
| 321 | return preg_match('/(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):?(\d{2})?/', $string); |
| 322 | } |
| 323 | |
| 324 | function rdf_qname_to_uri($qname) { |
| 325 | if (rdf_is_valid_qname($qname)) { |
| 326 | $namespaces = rdf_get_namespaces(); |
| 327 | list($prefix, $local_part) = explode(':', $qname, 2); |
| 328 | if (isset($namespaces[$prefix])) { |
| 329 | return $namespaces[$prefix] . $local_part; |
| 330 | } |
| 331 | } |
| 332 | return $qname; // FIXME! |
| 333 | } |
| 334 | |
| 335 | function rdf_qname_to_uriref($qname) { |
| 336 | return rdf_uri(rdf_qname_to_uri($qname)); // TODO: cache? |
| 337 | } |
| 338 | |
| 339 | function rdf_uri_to_qname($uri, $gensym = TRUE, $fail = NULL) { |
| 340 | global $rdf_namespaces; |
| 341 | if (empty($rdf_namespaces)) { |
| 342 | rdf_get_namespaces(); |
| 343 | } |
| 344 | |
| 345 | if (!rdf_is_valid_uri($uri = (string)$uri)) { |
| 346 | return $uri; |
| 347 | } |
| 348 | |
| 349 | $best_prefix = $best_match = ''; |
| 350 | |
| 351 | // Attempt to find the longest substring match |
| 352 | foreach ($rdf_namespaces as $prefix => $match) { |
| 353 | if (strpos($uri, $match) === 0 && strlen($match) > strlen($best_match)) { |
| 354 | $best_match = $match; |
| 355 | $best_prefix = $prefix; |
| 356 | } |
| 357 | } |
| 358 | |
| 359 | // If successful, life is easy |
| 360 | if (!empty($best_prefix)) { |
| 361 | $local_part = substr($uri, strlen($best_match)); |
| 362 | return implode(':', array($best_prefix, $local_part)); |
| 363 | } |
| 364 | |
| 365 | // No existing namespace prefix found, make one up |
| 366 | if ($gensym && preg_match('@([\w\d-_]+)$@', $uri, $matches)) { |
| 367 | static $gensym = 0; |
| 368 | $prefix = 'g.' . ++$gensym; // Good ol' Lisp tradition continues... |
| 369 | $local_part = $matches[1]; |
| 370 | $rdf_namespaces[$prefix] = substr($uri, 0, -strlen($local_part)); |
| 371 | return implode(':', array($prefix, $local_part)); |
| 372 | } |
| 373 | |
| 374 | //trigger_error('Could not convert URI ' . $uri . ' to QName', E_USER_WARNING); |
| 375 | return $fail; |
| 376 | } |
| 377 | |
| 378 | ////////////////////////////////////////////////////////////////////////////// |
| 379 | // ARC2 interoperability |
| 380 | |
| 381 | function _rdf_deconstruct_arc2_triple($triple) { |
| 382 | $subject = _rdf_deconstruct_arc2_value($triple, 's'); |
| 383 | $predicate = _rdf_deconstruct_arc2_value($triple, 'p'); |
| 384 | $object = _rdf_deconstruct_arc2_value($triple, 'o'); |
| 385 | return array($subject, $predicate, $object); |
| 386 | } |
| 387 | |
| 388 | function _rdf_deconstruct_arc2_value($triple, $name) { |
| 389 | switch ($name == 'p' ? 'iri' : $triple[$name . '_type']) { |
| 390 | case 'uri': |
| 391 | case 'iri': |
| 392 | return rdf_uri($triple[$name]); |
| 393 | case 'bnode': |
| 394 | return rdf_bnode($triple[$name]); |
| 395 | case 'literal': |
| 396 | case 'literal1': |
| 397 | case 'literal2': |
| 398 | case 'literal_long1': |
| 399 | case 'literal_long2': |
| 400 | return rdf_literal($triple[$name], $triple[$name . '_lang'], $triple[$name . '_datatype']); |
| 401 | case 'var': |
| 402 | return rdf_var($triple[$name]); |
| 403 | } |
| 404 | } |
| 405 | |
| 406 | ////////////////////////////////////////////////////////////////////////////// |
| 407 | // RDF/PHP normalization & serialization |
| 408 | |
| 409 | function rdf_normalize($input) { |
| 410 | $output = array(); |
| 411 | foreach ($input as $triple) { |
| 412 | list($subject, $predicate, $object) = $triple; |
| 413 | $output[(string)$subject][(string)$predicate][] = $object; |
| 414 | } |
| 415 | return $output; |
| 416 | } |
| 417 | |
| 418 | function rdf_denormalize($input) { |
| 419 | $output = array(); |
| 420 | foreach ($input as $subject => $predicates) { |
| 421 | foreach ($predicates as $predicate => $objects) { |
| 422 | if (!is_array($objects)) { |
| 423 | $output[] = array($subject, $predicate, $objects); |
| 424 | } |
| 425 | else { |
| 426 | foreach ($objects as $object) { |
| 427 | $output[] = array($subject, $predicate, $object); |
| 428 | } |
| 429 | } |
| 430 | } |
| 431 | } |
| 432 | return $output; |
| 433 | } |
| 434 | |
| 435 | function rdf_objectify($input) { |
| 436 | $output = array(); |
| 437 | foreach ($input as $s => &$ps) { |
| 438 | foreach ($ps as $p => &$os) { |
| 439 | foreach ($os as &$o) { |
| 440 | $output[$s][$p][] = rdf_objectify_value($o); |
| 441 | } |
| 442 | } |
| 443 | } |
| 444 | return $output; |
| 445 | } |
| 446 | |
| 447 | function rdf_objectify_value($value, &$bnodes = array()) { |
| 448 | switch ($value['type']) { |
| 449 | case 'bnode': |
| 450 | return rdf_uri($value['value']); // FIXME |
| 451 | case 'uri': |
| 452 | return rdf_uri($value['value']); |
| 453 | case 'literal': |
| 454 | return !isset($value['lang']) && !isset($value['datatype']) ? $value['value'] : rdf_literal($value['value'], $value['lang'], $value['datatype']); |
| 455 | } |
| 456 | } |
| 457 | |
| 458 | function rdf_deobjectify($input) { |
| 459 | $output = array(); |
| 460 | foreach ($input as $s => $ps) { |
| 461 | foreach ($ps as $p => $os) { |
| 462 | $os = is_array($os) ? $os : array($os); |
| 463 | foreach ($os as $o) { |
| 464 | $output[$s][$p][] = is_object($o) ? $o->to_array() : (!is_array($o) ? array('type' => 'literal', 'value' => (string)$o) : $o); // FIXME |
| 465 | } |
| 466 | } |
| 467 | } |
| 468 | return $output; |
| 469 | } |
| 470 | |
| 471 | ////////////////////////////////////////////////////////////////////////////// |
| 472 | // RDF/PHP serialization |
| 473 | |
| 474 | function rdf_serialize($data, array $options = array()) { |
| 475 | $data = is_array($data) ? $data : rdf_normalize($data); // support RDF_QueryIterator |
| 476 | $formats = rdf_get_formats('info', 'w'); |
| 477 | $format = isset($options['format']) ? $options['format'] : RDF_FORMAT; |
| 478 | if (!isset($formats[$format])) { |
| 479 | return FALSE; |
| 480 | } |
| 481 | if (isset($formats[$format]->file)) { |
| 482 | require_once './' . drupal_get_path('module', $formats[$format]->module) . '/' . $formats[$format]->file; |
| 483 | } |
| 484 | ob_start() && call_user_func($formats[$format]->serialize, $data, $options); |
| 485 | return ob_get_clean(); |
| 486 | } |
| 487 | |
| 488 | function rdf_unserialize($text, array $options = array()) { |
| 489 | $formats = rdf_get_formats('info', 'r'); |
| 490 | $format = isset($options['format']) ? $options['format'] : RDF_FORMAT; |
| 491 | if (isset($formats[$format]->file)) { |
| 492 | require_once './' . drupal_get_path('module', $formats[$format]->module) . '/' . $formats[$format]->file; |
| 493 | } |
| 494 | return isset($formats[$format]) ? call_user_func($formats[$format]->unserialize, $text, $options) : FALSE; |
| 495 | } |
| 496 | |
| 497 | /** |
| 498 | * @see http://n2.talis.com/wiki/RDF_JSON_Specification#rdf.2Fphp |
| 499 | */ |
| 500 | function rdf_serialize_php($data, array $options = array()) { |
| 501 | print serialize(rdf_deobjectify($data)); |
| 502 | } |
| 503 | |
| 504 | /** |
| 505 | * @see http://n2.talis.com/wiki/RDF_JSON_Specification#rdf.2Fphp |
| 506 | */ |
| 507 | function rdf_unserialize_php($text, array $options = array()) { |
| 508 | return rdf_objectify(unserialize((string)$text)); |
| 509 | } |
| 510 | |
| 511 | /** |
| 512 | * @see http://n2.talis.com/wiki/RDF_JSON_Specification |
| 513 | */ |
| 514 | function rdf_serialize_json($data, array $options = array()) { |
| 515 | print drupal_to_js(rdf_deobjectify($data)); |
| 516 | } |
| 517 | |
| 518 | /** |
| 519 | * @see http://n2.talis.com/wiki/RDF_JSON_Specification |
| 520 | */ |
| 521 | function rdf_unserialize_json($json, array $options = array()) { |
| 522 | return rdf_objectify(json_decode((string)$json, TRUE)); |
| 523 | } |
| 524 | |
| 525 | ////////////////////////////////////////////////////////////////////////////// |
| 526 | // RDF API query selectors |
| 527 | |
| 528 | function rdf_objects($objects) { |
| 529 | return is_array($objects) ? $objects : array($objects); |
| 530 | } |
| 531 | |
| 532 | function rdf_select_resources($input) { |
| 533 | return array_keys($input); |
| 534 | } |
| 535 | |
| 536 | function rdf_select_predicates($input) { |
| 537 | return !empty($input) ? array_unique(call_user_func_array('array_merge', rdf_select($input, FALSE, TRUE, FALSE))) : array(); |
| 538 | } |
| 539 | |
| 540 | function rdf_select_values($input) { |
| 541 | return !empty($input) ? array_unique(call_user_func_array('array_merge', rdf_select($input, FALSE, FALSE, TRUE))) : array(); |
| 542 | } |
| 543 | |
| 544 | function rdf_select($input, $subject = TRUE, $predicate = FALSE, $object = FALSE) { |
| 545 | $output = array(); |
| 546 | foreach ($input as $s => $ps) { |
| 547 | foreach ($ps as $p => $os) { |
| 548 | foreach ($os as $o) { |
| 549 | $triple = array(); |
| 550 | if ($subject) $triple[] = $s; |
| 551 | if ($predicate) $triple[] = $p; |
| 552 | if ($object) $triple[] = $o; |
| 553 | $output[] = $triple; |
| 554 | } |
| 555 | } |
| 556 | } |
| 557 | return $output; |
| 558 | } |
| 559 | |
| 560 | function _rdf_filter($input, $subject = NULL, $predicate = NULL, $object = NULL, $options = array()) { |
| 561 | extract($options, EXTR_SKIP | EXTR_REFS); |
| 562 | |
| 563 | $output = array(); |
| 564 | foreach ($input as $s => $ps) { |
| 565 | |
| 566 | foreach ($ps as $p => $os) { |
| 567 | foreach ($os as $o) { |
| 568 | if ((empty($callback) || $callback($s, $p, $o)) && |
| 569 | (!$subject || $subject == $s) && |
| 570 | (!$predicate || $predicate == $p) && |
| 571 | (!$object || $object == $o)) { // FIXME: RDF_Literals |
| 572 | $output[$s][$p][] = $o; |
| 573 | } |
| 574 | } |
| 575 | } |
| 576 | |
| 577 | if ($subject && $subject == $s) |
| 578 | break; // shortcut |
| 579 | } |
| 580 | return $output; |
| 581 | } |
| 582 | |
| 583 | ////////////////////////////////////////////////////////////////////////////// |
| 584 | // RDF/PHP handling |
| 585 | |
| 586 | // TODO: rename to rdf_predicates()? |
| 587 | function rdf_expand_qnames(array $input, $remove_empty = TRUE) { |
| 588 | $output = array(); |
| 589 | foreach ($input as $qname => $data) { |
| 590 | if (!empty($data)) { |
| 591 | $output[rdf_qname_to_uri($qname)] = is_array($data) ? $data : array($data); |
| 592 | } |
| 593 | } |
| 594 | return $output; |
| 595 | } |
| 596 | |
| 597 | function rdf_get_prefixes(array $data, $namespaces = NULL) { |
| 598 | $result = array('rdf' => 'http://www.w3.org/1999/02/22-rdf-syntax-ns#'); |
| 599 | $namespaces = is_array($namespaces) ? $namespaces : rdf_get_namespaces(); |
| 600 | |
| 601 | foreach ($data as $subject => $predicates) { |
| 602 | foreach ($predicates as $predicate => $objects) { |
| 603 | $qnames = array($predicate); |
| 604 | foreach (is_array($objects) ? $objects : array($objects) as $object) { |
| 605 | if (rdf_is_valid_uri((string)$object)) { |
| 606 | $qnames[] = $object; |
| 607 | } |
| 608 | } |
| 609 | foreach ($qnames as $qname) { |
| 610 | list($prefix, ) = explode(':', rdf_uri_to_qname($qname)); |
| 611 | if ($prefix != '_' && !isset($result[$prefix]) && isset($namespaces[$prefix])) { |
| 612 | $result[$prefix] = $namespaces[$prefix]; |
| 613 | } |
| 614 | } |
| 615 | } |
| 616 | } |
| 617 | return $result; |
| 618 | } |
| 619 | |
| 620 | ////////////////////////////////////////////////////////////////////////////// |
| 621 | // RDF API functions |
| 622 | |
| 623 | /** |
| 624 | * Adds an RDF auto-discovery <link> tag to the page's <head> element. |
| 625 | */ |
| 626 | function rdf_add_autodiscovery_link($title, $path, $format = RDF_FORMAT, array $options = array()) { |
| 627 | $formats = rdf_get_formats(); |
| 628 | drupal_add_link(array_merge(array('rel' => 'meta', 'type' => $formats[$format]->mime_type, 'title' => $title, 'href' => $path), $options)); |
| 629 | } |
| 630 | |
| 631 | function rdf_get_uuid() { |
| 632 | return sprintf('%04x%04x-%04x-%04x-%04x-%04x%04x%04x', |
| 633 | mt_rand(0, 0xffff), mt_rand(0, 0xffff), mt_rand(0, 0xffff), |
| 634 | mt_rand(0, 0x0fff) | 0x4000, |
| 635 | mt_rand(0, 0x3fff) | 0x8000, |
| 636 | mt_rand(0, 0xffff), mt_rand(0, 0xffff), mt_rand(0, 0xffff)); |
| 637 | } |
| 638 | |
| 639 | function rdf_get_formats($what = 'info', $mode = '') { |
| 640 | $formats = array(); |
| 641 | foreach (module_implements('rdf_formats') as $module) { |
| 642 | if ($result = module_invoke($module, 'rdf_formats')) { |
| 643 | foreach ($result as $k => &$v) { |
| 644 | $formats[$k] = isset($formats[$k]) ? array_merge($formats[$k], $v) : $v; |
| 645 | $formats[$k]['name'] = $k; |
| 646 | $formats[$k]['module'] = $module; |
| 647 | } |
| 648 | } |
| 649 | } |
| 650 | ksort($formats); |
| 651 | |
| 652 | foreach ($formats as $k => &$v) { |
| 653 | $formats[$k] = (object)$v; |
| 654 | } |
| 655 | |
| 656 | if (preg_match('/^[rw]$/', $mode)) { |
| 657 | foreach ($formats as $k => &$v) { |
| 658 | if ((strpos($mode, 'r') !== FALSE && !isset($v->unserialize)) || |
| 659 | (strpos($mode, 'w') !== FALSE && !isset($v->serialize))) { |
| 660 | unset($formats[$k]); |
| 661 | } |
| 662 | } |
| 663 | } |
| 664 | |
| 665 | if ($what == 'names') { |
| 666 | foreach ($formats as $k => &$v) { $formats[$k] = $v->title; } |
| 667 | } |
| 668 | |
| 669 | return $formats; |
| 670 | } |
| 671 | |
| 672 | function rdf_get_repositories($what = 'info', $filters = array()) { |
| 673 | $repos = module_invoke_all('rdf_repositories'); |
| 674 | if (!empty($filters)) { |
| 675 | foreach ($repos as $k => &$v) { |
| 676 | foreach ($filters as $filter => $value) { |
| 677 | if ($v[$filter] != $value) { |
| 678 | unset($repos[$k]); |
| 679 | continue 2; |
| 680 | } |
| 681 | } |
| 682 | } |
| 683 | } |
| 684 | if ($what == 'names') { |
| 685 | foreach ($repos as $k => &$v) { |
| 686 | $repos[$k] = $v['title']; |
| 687 | } |
| 688 | } |
| 689 | return $repos; |
| 690 | } |
| 691 | |
| 692 | function rdf_register_namespace($prefix, $uri) { |
| 693 | rdf_get_namespaces(); |
| 694 | $GLOBALS['rdf_namespaces'][$prefix] = $uri; |
| 695 | } |
| 696 | |
| 697 | function rdf_get_namespaces($op = NULL) { |
| 698 | global $rdf_namespaces; |
| 699 | if (empty($rdf_namespaces)) { |
| 700 | $rdf_namespaces = module_invoke_all('rdf_namespaces'); |
| 701 | ksort($rdf_namespaces); |
| 702 | } |
| 703 | |
| 704 | switch ($op) { |
| 705 | case 'rdfa': // only RDFa-enabled namespaces |
| 706 | $defaults = array('rdf', 'dc', 'foaf'); |
| 707 | $defaults = array_combine($defaults, $defaults); |
| 708 | return array_intersect_key($rdf_namespaces, array_filter(variable_get('rdf_rdfa_prefixes', $defaults), 'is_string')); |
| 709 | default: // all namespaces |
| 710 | return $rdf_namespaces; |
| 711 | } |
| 712 | } |
| 713 | |
| 714 | function rdf_get_contexts() { |
| 715 | return module_invoke_all('rdf_contexts'); |
| 716 | } |
| 717 | |
| 718 | function rdf_get_predicates($prefix) { |
| 719 | $predicates = module_invoke_all('rdf_predicates'); |
| 720 | return isset($predicates[$prefix]) ? $predicates[$prefix] : array(); |
| 721 | } |
| 722 | |
| 723 | function rdf_get_type($value) { |
| 724 | if (!is_object($value)) { |
| 725 | return 'string'; // plain literal |
| 726 | } |
| 727 | else if ($value instanceof RDF_Literal) { |
| 728 | return 'literal'; // language/datatype-tagged literal |
| 729 | } |
| 730 | else { // RDF_URIRef, or the like |
| 731 | return 'uri'; // TODO: bnode |
| 732 | } |
| 733 | } |
| 734 | |
| 735 | function rdf_get_datatype($value) { |
| 736 | switch (gettype($value)) { |
| 737 | case 'object': return ($value instanceof RDF_Literal) ? $value->datatype : NULL; |
| 738 | case 'NULL': return NULL; |
| 739 | case 'boolean': return 'xsd:boolean'; |
| 740 | case 'integer': return 'xsd:int'; |
| 741 | case 'double': return 'xsd:double'; |
| 742 | case 'string': //return 'xsd:string'; |
| 743 | default: return NULL; |
| 744 | } |
| 745 | } |
| 746 | |
| 747 | function rdf_load_site() { |
| 748 | return array( |
| 749 | dc::type => dcmitype::uriref('Service'), |
| 750 | dc::format => 'text/html', |
| 751 | dc::language => array_keys(language_list()), |
| 752 | dc::title => rdf_literal(variable_get('site_name', 'Drupal'), 'en'), |
| 753 | dc::description => variable_get('site_mission', ''), |
| 754 | dc::publisher => rdf_mailto(variable_get('site_mail', ini_get('sendmail_from'))), |
| 755 | dc::creator => rdf_uri('http://drupal.org/#' . DRUPAL_CORE_COMPATIBILITY), |
| 756 | ); |
| 757 | } |
| 758 | |
| 759 | function rdf_get_feed_info($feed_id = NULL, $enabled_only = FALSE) { |
| 760 | $feeds = module_invoke_all('rdf_feeds'); |
| 761 | if ($feed_id) { |
| 762 | return isset($feeds[$feed_id]) ? (object)array_merge(array('id' => $feed_id), $feeds[$feed_id]) : NULL; |
| 763 | } |
| 764 | else { |
| 765 | foreach ($feeds as $feed_id => &$feed) { |
| 766 | $feeds[$feed_id] = $feed = (object)array_merge(array('id' => $feed_id), $feed); |
| 767 | if ($enabled_only && !module_exists($feed->module)) { |
| 768 | unset($feeds[$feed_id]); |
| 769 | } |
| 770 | } |
| 771 | return $feeds; |
| 772 | } |
| 773 | } |
| 774 | |
| 775 | function rdf_get_feed_settings($feed) { |
| 776 | $defaults = array('description_from_mission' => '', 'description' => '', 'update_period' => '', 'update_frequency' => '', 'update_base' => '', 'format' => RDF_FORMAT_RSS); |
| 777 | if (($feed = is_object($feed) ? $feed : rdf_get_feed_info($feed))) { |
| 778 | return ($feed->module == 'views') ? // special case for Views feeds |
| 779 | rdf_views_get_feed_settings($feed->id, $defaults) : |
| 780 | variable_get('rdf_feed[' . $feed->id . ']', $defaults); |
| 781 | } |
| 782 | return $defaults; |
| 783 | } |
| 784 | |
| 785 | function rdf_set_feed_settings($feed, $settings) { |
| 786 | if (($feed = is_object($feed) ? $feed : rdf_get_feed_info($feed))) { |
| 787 | if ($settings) { |
| 788 | variable_set('rdf_feed[' . $feed->id . ']', (array)$settings); |
| 789 | } |
| 790 | else { |
| 791 | variable_del('rdf_feed[' . $feed->id . ']'); |
| 792 | } |
| 793 | } |
| 794 | } |
| 795 | |
| 796 | ////////////////////////////////////////////////////////////////////////////// |
| 797 | // Miscellaneous |
| 798 | |
| 799 | function _rdf_query_arg($uri_or_qname) { |
| 800 | if (is_string($uri_or_qname) && preg_match('/^[\w]+:[\w]+$/i', $uri_or_qname)) |
| 801 | return rdf_qname_to_uri($uri_or_qname); |
| 802 | return is_object($uri_or_qname) ? (string)$uri_or_qname : $uri_or_qname; |
| 803 | } |
| 804 | |
| 805 | function _rdf_invoke_op($name, $args, $repos = NULL, $default = FALSE) { |
| 806 | call_user_func_array('module_invoke_all', array_merge(array('rdf'), $args)); // trigger hook_rdf() |
| 807 | |
| 808 | foreach (_rdf_get_callbacks($name, $repos) as $callback) { |
| 809 | list($callable, $callable_args) = $callback; |
| 810 | if ($result = call_user_func_array($callable, array_merge($callable_args, $args))) { |
| 811 | return $result; |
| 812 | } |
| 813 | } |
| 814 | return $default; |
| 815 | } |
| 816 | |
| 817 | function _rdf_get_callbacks($op, $repos = NULL) { |
| 818 | $callbacks = array(); |
| 819 | $repos = !empty($repos) ? $repos : (isset($GLOBALS['rdf_repository']) ? $GLOBALS['rdf_repository'] : NULL); |
| 820 | $repos = !empty($repos) && !is_array($repos) ? array($repos) : $repos; |
| 821 | $repos = !empty($repos) ? array_intersect_key(rdf_get_repositories(), array_flip($repos)) : rdf_get_repositories(); |
| 822 | |
| 823 | foreach ($repos as $repo) { |
| 824 | if (isset($repo['callbacks'][$op])) { |
| 825 | $callback = $repo['callbacks'][$op]['function']; |
| 826 | if (is_callable($callback)) { |
| 827 | $args = is_array($repo['callbacks'][$op]['arguments']) ? $repo['callbacks'][$op]['arguments'] : array(); |
| 828 | $callbacks[] = array($callback, $args); |
| 829 | } |
| 830 | } |
| 831 | } |
| 832 | |
| 833 | return $callbacks; |
| 834 | } |
| 835 | |
| 836 | ////////////////////////////////////////////////////////////////////////////// |
| 837 | // RDF API classes |
| 838 | |
| 839 | class RDF_Callback { |
| 840 | public function __construct($callback, array $arguments = array()) { |
| 841 | $this->callback = $callback; |
| 842 | $this->arguments = $arguments; |
| 843 | } |
| 844 | |
| 845 | public function call() { |
| 846 | $arguments = func_get_args(); |
| 847 | return call_user_func_array($this->callback, array_merge($this->arguments, $arguments)); |
| 848 | } |
| 849 | } |
| 850 | |
| 851 | /** |
| 852 | * @see http://www.php.net/~helly/php/ext/spl/interfaceIterator.html |
| 853 | */ |
| 854 | class RDF_CallbackIterator implements Iterator { |
| 855 | public function __construct($callback, array $args_lhs, $args_iter, array $args_rhs = array()) { |
| 856 | $this->callback = $callback; |
| 857 | $this->args_lhs = $args_lhs; |
| 858 | $this->args_iter = $args_iter; |
| 859 | $this->args_rhs = $args_rhs; |
| 860 | $this->done = FALSE; |
| 861 | $this->key = NULL; |
| 862 | $this->value = NULL; |
| 863 | } |
| 864 | |
| 865 | public function call($arg_iter) { |
| 866 | $result = call_user_func_array($this->callback, array_merge($this->args_lhs, array($arg_iter), $this->args_rhs)); |
| 867 | list($this->key, $this->value) = each($result); |
| 868 | } |
| 869 | |
| 870 | public function rewind() { |
| 871 | $this->done = FALSE; |
| 872 | reset($this->args_iter); |
| 873 | $this->next(); |
| 874 | } |
| 875 | |
| 876 | public function next() { |
| 877 | if (($kv = each($this->args_iter)) !== FALSE) { |
| 878 | list($key, $value) = $kv; |
| 879 | $this->call($value); |
| 880 | } |
| 881 | else { |
| 882 | $this->done = TRUE; |
| 883 | } |
| 884 | } |
| 885 | |
| 886 | public function valid() { return !$this->done; } |
| 887 | public function current() { return $this->value; } |
| 888 | public function key() { return $this->key; } |
| 889 | } |
| 890 | |
| 891 | /** |
| 892 | * @see http://www.php.net/~helly/php/ext/spl/interfaceIteratorAggregate.html |
| 893 | */ |
| 894 | class RDF_QueryCallback extends RDF_Callback implements IteratorAggregate { |
| 895 | public function call() { |
| 896 | return call_user_func_array($this->callback, $this->arguments); |
| 897 | } |
| 898 | |
| 899 | public function getIterator() { |
| 900 | $result = $this->call(); |
| 901 | return is_object($result) ? $result : new ArrayIterator(is_array($result) ? $result : array()); |
| 902 | } |
| 903 | } |
| 904 | |
| 905 | /** |
| 906 | * @see http://www.php.net/~helly/php/ext/spl/classAppendIterator.html |
| 907 | */ |
| 908 | class RDF_QueryIterator extends AppendIterator { |
| 909 | public function __construct() { |
| 910 | parent::__construct(); |
| 911 | $this->rewind(); |
| 912 | foreach (func_get_args() as $iterator) { |
| 913 | $this->append($iterator); |
| 914 | } |
| 915 | } |
| 916 | |
| 917 | public function key() { |
| 918 | // By reindexing the aggregated results, we guarantee that e.g. |
| 919 | // iterator_to_array() will work correctly despite overlapping keys |
| 920 | // likely being returned by the inner iterators. |
| 921 | return $this->index++; |
| 922 | } |
| 923 | |
| 924 | public function rewind() { |
| 925 | $this->index = 0; |
| 926 | return parent::rewind(); |
| 927 | } |
| 928 | |
| 929 | public function to_array() { |
| 930 | return iterator_to_array($this); |
| 931 | } |
| 932 | } |
| 933 | |
| 934 | class RDF_Statement { |
| 935 | public $subject, $predicate, $object; |
| 936 | |
| 937 | public function __construct($subject, $predicate, $object) { |
| 938 | foreach (get_defined_vars() as $k => $v) { |
| 939 | $this->$k = $v; |
| 940 | } |
| 941 | } |
| 942 | |
| 943 | public function to_n3() { |
| 944 | // TODO |
| 945 | } |
| 946 | } |
| 947 | |
| 948 | /** |
| 949 | * @see http://www.w3.org/TR/rdf-concepts/#section-Graph-URIref |
| 950 | */ |
| 951 | class RDF_URIRef { |
| 952 | public static $resources = array(); |
| 953 | public $uri; |
| 954 | |
| 955 | public static function uri($uri, $class = __CLASS__) { |
| 956 | if (is_object($uri) && $uri instanceof RDF_URIRef) { |
| 957 | return $uri; // for convenience |
| 958 | } |
| 959 | if (!array_key_exists($uri, self::$resources)) { |
| 960 | $resource = new $class($uri); |
| 961 | self::$resources[$uri] = $resource; |
| 962 | return $resource; |
| 963 | } |
| 964 | return self::$resources[$uri]; |
| 965 | } |
| 966 | |
| 967 | public function qname() { |
| 968 | return rdf_uri_to_qname($this->uri); |
| 969 | } |
| 970 | |
| 971 | public function to_array() { |
| 972 | return array('type' => 'uri', 'value' => $this->uri); |
| 973 | } |
| 974 | |
| 975 | public function to_n3() { |
| 976 | return '<' . $this->uri . '>'; |
| 977 | } |
| 978 | |
| 979 | public function __toString() { |
| 980 | return $this->uri; |
| 981 | } |
| 982 | |
| 983 | protected function __construct($uri) { |
| 984 | $this->uri = $uri; |
| 985 | } |
| 986 | } |
| 987 | |
| 988 | /** |
| 989 | * @see http://www.w3.org/TR/rdf-concepts/#section-blank-nodes |
| 990 | */ |
| 991 | class RDF_BNode extends RDF_URIRef { |
| 992 | public static function match($uri) { |
| 993 | return strpos($uri, 'http://bnode.net/') === 0; |
| 994 | } |
| 995 | |
| 996 | public static function generate() { |
| 997 | return self::id(rdf_get_uuid()); |
| 998 | } |
| 999 | |
| 1000 | public static function id($id) { |
| 1001 | return self::uri('http://bnode.net/' . $id, __CLASS__); |
| 1002 | } |
| 1003 | |
| 1004 | public function qname() { |
| 1005 | return '_:' . $id; |
| 1006 | } |
| 1007 | |
| 1008 | public function to_array() { |
| 1009 | return array('type' => 'bnode', 'value' => $this->uri); |
| 1010 | } |
| 1011 | |
| 1012 | public function to_n3() { |
| 1013 | return '_:' . substr($this->uri, strlen('http://bnode.net/')); // FIXME |
| 1014 | } |
| 1015 | } |
| 1016 | |
| 1017 | /** |
| 1018 | * @see http://www.w3.org/TR/rdf-concepts/#section-Graph-Literal |
| 1019 | */ |
| 1020 | class RDF_Literal { |
| 1021 | public $value, $language, $datatype; |
| 1022 | |
| 1023 | public function __construct($value, $language = NULL, $datatype = NULL) { |
| 1024 | $this->value = $value; |
| 1025 | $this->language = $language ? strtolower($language) : NULL; |
| 1026 | $this->datatype = $datatype ? rdf_qname_to_uri($datatype) : NULL; |
| 1027 | } |
| 1028 | |
| 1029 | public function qname() { |
| 1030 | return rdf_uri_to_qname($this->datatype); |
| 1031 | } |
| 1032 | |
| 1033 | public function to_array() { |
| 1034 | $array = array('type' => 'literal', 'value' => $this->value); |
| 1035 | if ($this->language) { |
| 1036 | $array['lang'] = $this->language; |
| 1037 | } |
| 1038 | if ($this->datatype) { |
| 1039 | $array['datatype'] = $this->datatype; |
| 1040 | } |
| 1041 | return $array; |
| 1042 | } |
| 1043 | |
| 1044 | public function to_n3() { |
| 1045 | return $this->__toString(); |
| 1046 | } |
| 1047 | |
| 1048 | public function __toString() { |
| 1049 | return '"' . $this->value . '"' . // FIXME |
| 1050 | ($this->language ? '@' . $this->language : '') . |
| 1051 | ($this->datatype ? '^^<' . $this->qname() . '>' : ''); |
| 1052 | } |
| 1053 | } |
| 1054 | |
| 1055 | /** |
| 1056 | * @see http://www.w3.org/TR/rdf-concepts/#section-XMLLiteral |
| 1057 | */ |
| 1058 | class RDF_XMLLiteral {} // TODO |
| 1059 | |
| 1060 | class RDF_Variable { |
| 1061 | public $name; |
| 1062 | |
| 1063 | function __construct($name) { |
| 1064 | $this->name = $name; |
| 1065 | } |
| 1066 | |
| 1067 | function to_n3() { |
| 1068 | return $this->__toString(); |
| 1069 | } |
| 1070 | |
| 1071 | function __toString() { |
| 1072 | return '?' . $this->name; |
| 1073 | } |
| 1074 | } |
| 1075 | |
| 1076 | class RDF_Collection implements ArrayAccess { |
| 1077 | public $items, $uri; |
| 1078 | |
| 1079 | function __construct(array $items = array()) { |
| 1080 | $this->items = $items; |
| 1081 | $this->uri = rdf_bnode(); |
| 1082 | } |
| 1083 | |
| 1084 | function offsetExists($offset) { return isset($this->items[$offset]); } |
| 1085 | function offsetGet($offset) { return $this->items[$offset]; } |
| 1086 | function offsetSet($offset, $value) { return is_null($offset) ? $this->items[] = $value : $this->items[$offset] = $value; } |
| 1087 | function offsetUnset($offset) { unset($this->items[$offset]); } |
| 1088 | |
| 1089 | function uriref() { return $this->uri; } |