web/wp-includes/feed.php
branchwordpress
changeset 109 03b0d1493584
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equal deleted inserted replaced
-1:000000000000 109:03b0d1493584
       
     1 <?php
       
     2 /**
       
     3  * WordPress Feed API
       
     4  *
       
     5  * Many of the functions used in here belong in The Loop, or The Loop for the
       
     6  * Feeds.
       
     7  *
       
     8  * @package WordPress
       
     9  * @subpackage Feed
       
    10  */
       
    11 
       
    12 /**
       
    13  * RSS container for the bloginfo function.
       
    14  *
       
    15  * You can retrieve anything that you can using the get_bloginfo() function.
       
    16  * Everything will be stripped of tags and characters converted, when the values
       
    17  * are retrieved for use in the feeds.
       
    18  *
       
    19  * @package WordPress
       
    20  * @subpackage Feed
       
    21  * @since 1.5.1
       
    22  * @uses apply_filters() Calls 'get_bloginfo_rss' hook with two parameters.
       
    23  * @see get_bloginfo() For the list of possible values to display.
       
    24  *
       
    25  * @param string $show See get_bloginfo() for possible values.
       
    26  * @return string
       
    27  */
       
    28 function get_bloginfo_rss($show = '') {
       
    29 	$info = strip_tags(get_bloginfo($show));
       
    30 	return apply_filters('get_bloginfo_rss', convert_chars($info), $show);
       
    31 }
       
    32 
       
    33 /**
       
    34  * Display RSS container for the bloginfo function.
       
    35  *
       
    36  * You can retrieve anything that you can using the get_bloginfo() function.
       
    37  * Everything will be stripped of tags and characters converted, when the values
       
    38  * are retrieved for use in the feeds.
       
    39  *
       
    40  * @package WordPress
       
    41  * @subpackage Feed
       
    42  * @since 0.71
       
    43  * @uses apply_filters() Calls 'bloginfo_rss' hook with two parameters.
       
    44  * @see get_bloginfo() For the list of possible values to display.
       
    45  *
       
    46  * @param string $show See get_bloginfo() for possible values.
       
    47  */
       
    48 function bloginfo_rss($show = '') {
       
    49 	echo apply_filters('bloginfo_rss', get_bloginfo_rss($show), $show);
       
    50 }
       
    51 
       
    52 /**
       
    53  * Retrieve the default feed.
       
    54  *
       
    55  * The default feed is 'rss2', unless a plugin changes it through the
       
    56  * 'default_feed' filter.
       
    57  *
       
    58  * @package WordPress
       
    59  * @subpackage Feed
       
    60  * @since 2.5
       
    61  * @uses apply_filters() Calls 'default_feed' hook on the default feed string.
       
    62  *
       
    63  * @return string Default feed, or for example 'rss2', 'atom', etc.
       
    64  */
       
    65 function get_default_feed() {
       
    66 	return apply_filters('default_feed', 'rss2');
       
    67 }
       
    68 
       
    69 /**
       
    70  * Retrieve the blog title for the feed title.
       
    71  *
       
    72  * @package WordPress
       
    73  * @subpackage Feed
       
    74  * @since 2.2.0
       
    75  * @uses apply_filters() Calls 'get_wp_title_rss' hook on title.
       
    76  * @uses wp_title() See function for $sep parameter usage.
       
    77  *
       
    78  * @param string $sep Optional.How to separate the title. See wp_title() for more info.
       
    79  * @return string Error message on failure or blog title on success.
       
    80  */
       
    81 function get_wp_title_rss($sep = '&#187;') {
       
    82 	$title = wp_title($sep, false);
       
    83 	if ( is_wp_error( $title ) )
       
    84 		return $title->get_error_message();
       
    85 	$title = apply_filters('get_wp_title_rss', $title);
       
    86 	return $title;
       
    87 }
       
    88 
       
    89 /**
       
    90  * Display the blog title for display of the feed title.
       
    91  *
       
    92  * @package WordPress
       
    93  * @subpackage Feed
       
    94  * @since 2.2.0
       
    95  * @uses apply_filters() Calls 'wp_title_rss' on the blog title.
       
    96  * @see wp_title() $sep parameter usage.
       
    97  *
       
    98  * @param string $sep Optional.
       
    99  */
       
   100 function wp_title_rss($sep = '&#187;') {
       
   101 	echo apply_filters('wp_title_rss', get_wp_title_rss($sep));
       
   102 }
       
   103 
       
   104 /**
       
   105  * Retrieve the current post title for the feed.
       
   106  *
       
   107  * @package WordPress
       
   108  * @subpackage Feed
       
   109  * @since 2.0.0
       
   110  * @uses apply_filters() Calls 'the_title_rss' on the post title.
       
   111  *
       
   112  * @return string Current post title.
       
   113  */
       
   114 function get_the_title_rss() {
       
   115 	$title = get_the_title();
       
   116 	$title = apply_filters('the_title_rss', $title);
       
   117 	return $title;
       
   118 }
       
   119 
       
   120 /**
       
   121  * Display the post title in the feed.
       
   122  *
       
   123  * @package WordPress
       
   124  * @subpackage Feed
       
   125  * @since 0.71
       
   126  * @uses get_the_title_rss() Used to retrieve current post title.
       
   127  */
       
   128 function the_title_rss() {
       
   129 	echo get_the_title_rss();
       
   130 }
       
   131 
       
   132 /**
       
   133  * Display the post content for the feed.
       
   134  *
       
   135  * For encoding the html or the $encode_html parameter, there are three possible
       
   136  * values. '0' will make urls footnotes and use make_url_footnote(). '1' will
       
   137  * encode special characters and automatically display all of the content. The
       
   138  * value of '2' will strip all HTML tags from the content.
       
   139  *
       
   140  * Also note that you cannot set the amount of words and not set the html
       
   141  * encoding. If that is the case, then the html encoding will default to 2,
       
   142  * which will strip all HTML tags.
       
   143  *
       
   144  * To restrict the amount of words of the content, you can use the cut
       
   145  * parameter. If the content is less than the amount, then there won't be any
       
   146  * dots added to the end. If there is content left over, then dots will be added
       
   147  * and the rest of the content will be removed.
       
   148  *
       
   149  * @package WordPress
       
   150  * @subpackage Feed
       
   151  * @since 0.71
       
   152  * @uses apply_filters() Calls 'the_content_rss' on the content before processing.
       
   153  * @see get_the_content() For the $more_link_text, $stripteaser, and $more_file
       
   154  *		parameters.
       
   155  *
       
   156  * @param string $more_link_text Optional. Text to display when more content is available but not displayed.
       
   157  * @param int|bool $stripteaser Optional. Default is 0.
       
   158  * @param string $more_file Optional.
       
   159  * @param int $cut Optional. Amount of words to keep for the content.
       
   160  * @param int $encode_html Optional. How to encode the content.
       
   161  */
       
   162 function the_content_rss($more_link_text='(more...)', $stripteaser=0, $more_file='', $cut = 0, $encode_html = 0) {
       
   163 	$content = get_the_content($more_link_text, $stripteaser, $more_file);
       
   164 	$content = apply_filters('the_content_rss', $content);
       
   165 	if ( $cut && !$encode_html )
       
   166 		$encode_html = 2;
       
   167 	if ( 1== $encode_html ) {
       
   168 		$content = esc_html($content);
       
   169 		$cut = 0;
       
   170 	} elseif ( 0 == $encode_html ) {
       
   171 		$content = make_url_footnote($content);
       
   172 	} elseif ( 2 == $encode_html ) {
       
   173 		$content = strip_tags($content);
       
   174 	}
       
   175 	if ( $cut ) {
       
   176 		$blah = explode(' ', $content);
       
   177 		if ( count($blah) > $cut ) {
       
   178 			$k = $cut;
       
   179 			$use_dotdotdot = 1;
       
   180 		} else {
       
   181 			$k = count($blah);
       
   182 			$use_dotdotdot = 0;
       
   183 		}
       
   184 
       
   185 		/** @todo Check performance, might be faster to use array slice instead. */
       
   186 		for ( $i=0; $i<$k; $i++ )
       
   187 			$excerpt .= $blah[$i].' ';
       
   188 		$excerpt .= ($use_dotdotdot) ? '...' : '';
       
   189 		$content = $excerpt;
       
   190 	}
       
   191 	$content = str_replace(']]>', ']]&gt;', $content);
       
   192 	echo $content;
       
   193 }
       
   194 
       
   195 /**
       
   196  * Display the post excerpt for the feed.
       
   197  *
       
   198  * @package WordPress
       
   199  * @subpackage Feed
       
   200  * @since 0.71
       
   201  * @uses apply_filters() Calls 'the_excerpt_rss' hook on the excerpt.
       
   202  */
       
   203 function the_excerpt_rss() {
       
   204 	$output = get_the_excerpt();
       
   205 	echo apply_filters('the_excerpt_rss', $output);
       
   206 }
       
   207 
       
   208 /**
       
   209  * Display the permalink to the post for use in feeds.
       
   210  *
       
   211  * @package WordPress
       
   212  * @subpackage Feed
       
   213  * @since 2.3.0
       
   214  * @uses apply_filters() Call 'the_permalink_rss' on the post permalink
       
   215  */
       
   216 function the_permalink_rss() {
       
   217 	echo apply_filters('the_permalink_rss', get_permalink());
       
   218 }
       
   219 
       
   220 /**
       
   221  * Display the feed GUID for the current comment.
       
   222  *
       
   223  * @package WordPress
       
   224  * @subpackage Feed
       
   225  * @since unknown
       
   226  *
       
   227  * @param int|object $comment_id Optional comment object or id. Defaults to global comment object.
       
   228  */
       
   229 function comment_guid($comment_id = null) {
       
   230 	echo get_comment_guid($comment_id);
       
   231 }
       
   232 
       
   233 /**
       
   234  * Retrieve the feed GUID for the current comment.
       
   235  *
       
   236  * @package WordPress
       
   237  * @subpackage Feed
       
   238  * @since unknown
       
   239  *
       
   240  * @param int|object $comment_id Optional comment object or id. Defaults to global comment object.
       
   241  * @return bool|string false on failure or guid for comment on success.
       
   242  */
       
   243 function get_comment_guid($comment_id = null) {
       
   244 	$comment = get_comment($comment_id);
       
   245 
       
   246 	if ( !is_object($comment) )
       
   247 		return false;
       
   248 
       
   249 	return get_the_guid($comment->comment_post_ID) . '#comment-' . $comment->comment_ID;
       
   250 }
       
   251 
       
   252 /**
       
   253  * Display the link to the comments.
       
   254  *
       
   255  * @since 1.5.0
       
   256  */
       
   257 function comment_link() {
       
   258 	echo esc_url( get_comment_link() );
       
   259 }
       
   260 
       
   261 /**
       
   262  * Retrieve the current comment author for use in the feeds.
       
   263  *
       
   264  * @package WordPress
       
   265  * @subpackage Feed
       
   266  * @since 2.0.0
       
   267  * @uses apply_filters() Calls 'comment_author_rss' hook on comment author.
       
   268  * @uses get_comment_author()
       
   269  *
       
   270  * @return string Comment Author
       
   271  */
       
   272 function get_comment_author_rss() {
       
   273 	return apply_filters('comment_author_rss', get_comment_author() );
       
   274 }
       
   275 
       
   276 /**
       
   277  * Display the current comment author in the feed.
       
   278  *
       
   279  * @package WordPress
       
   280  * @subpackage Feed
       
   281  * @since 1.0.0
       
   282  */
       
   283 function comment_author_rss() {
       
   284 	echo get_comment_author_rss();
       
   285 }
       
   286 
       
   287 /**
       
   288  * Display the current comment content for use in the feeds.
       
   289  *
       
   290  * @package WordPress
       
   291  * @subpackage Feed
       
   292  * @since 1.0.0
       
   293  * @uses apply_filters() Calls 'comment_text_rss' filter on comment content.
       
   294  * @uses get_comment_text()
       
   295  */
       
   296 function comment_text_rss() {
       
   297 	$comment_text = get_comment_text();
       
   298 	$comment_text = apply_filters('comment_text_rss', $comment_text);
       
   299 	echo $comment_text;
       
   300 }
       
   301 
       
   302 /**
       
   303  * Retrieve all of the post categories, formatted for use in feeds.
       
   304  *
       
   305  * All of the categories for the current post in the feed loop, will be
       
   306  * retrieved and have feed markup added, so that they can easily be added to the
       
   307  * RSS2, Atom, or RSS1 and RSS0.91 RDF feeds.
       
   308  *
       
   309  * @package WordPress
       
   310  * @subpackage Feed
       
   311  * @since 2.1.0
       
   312  * @uses apply_filters()
       
   313  *
       
   314  * @param string $type Optional, default is 'rss'. Either 'rss', 'atom', or 'rdf'.
       
   315  * @return string All of the post categories for displaying in the feed.
       
   316  */
       
   317 function get_the_category_rss($type = 'rss') {
       
   318 	$categories = get_the_category();
       
   319 	$tags = get_the_tags();
       
   320 	$the_list = '';
       
   321 	$cat_names = array();
       
   322 
       
   323 	$filter = 'rss';
       
   324 	if ( 'atom' == $type )
       
   325 		$filter = 'raw';
       
   326 
       
   327 	if ( !empty($categories) ) foreach ( (array) $categories as $category ) {
       
   328 		$cat_names[] = sanitize_term_field('name', $category->name, $category->term_id, 'category', $filter);
       
   329 	}
       
   330 
       
   331 	if ( !empty($tags) ) foreach ( (array) $tags as $tag ) {
       
   332 		$cat_names[] = sanitize_term_field('name', $tag->name, $tag->term_id, 'post_tag', $filter);
       
   333 	}
       
   334 
       
   335 	$cat_names = array_unique($cat_names);
       
   336 
       
   337 	foreach ( $cat_names as $cat_name ) {
       
   338 		if ( 'rdf' == $type )
       
   339 			$the_list .= "\t\t<dc:subject><![CDATA[$cat_name]]></dc:subject>\n";
       
   340 		elseif ( 'atom' == $type )
       
   341 			$the_list .= sprintf( '<category scheme="%1$s" term="%2$s" />', esc_attr( apply_filters( 'get_bloginfo_rss', get_bloginfo( 'url' ) ) ), esc_attr( $cat_name ) );
       
   342 		else
       
   343 			$the_list .= "\t\t<category><![CDATA[" . @html_entity_decode( $cat_name, ENT_COMPAT, get_option('blog_charset') ) . "]]></category>\n";
       
   344 	}
       
   345 
       
   346 	return apply_filters('the_category_rss', $the_list, $type);
       
   347 }
       
   348 
       
   349 /**
       
   350  * Display the post categories in the feed.
       
   351  *
       
   352  * @package WordPress
       
   353  * @subpackage Feed
       
   354  * @since 0.71
       
   355  * @see get_the_category_rss() For better explanation.
       
   356  *
       
   357  * @param string $type Optional, default is 'rss'. Either 'rss', 'atom', or 'rdf'.
       
   358  */
       
   359 function the_category_rss($type = 'rss') {
       
   360 	echo get_the_category_rss($type);
       
   361 }
       
   362 
       
   363 /**
       
   364  * Display the HTML type based on the blog setting.
       
   365  *
       
   366  * The two possible values are either 'xhtml' or 'html'.
       
   367  *
       
   368  * @package WordPress
       
   369  * @subpackage Feed
       
   370  * @since 2.2.0
       
   371  */
       
   372 function html_type_rss() {
       
   373 	$type = get_bloginfo('html_type');
       
   374 	if (strpos($type, 'xhtml') !== false)
       
   375 		$type = 'xhtml';
       
   376 	else
       
   377 		$type = 'html';
       
   378 	echo $type;
       
   379 }
       
   380 
       
   381 /**
       
   382  * Display the rss enclosure for the current post.
       
   383  *
       
   384  * Uses the global $post to check whether the post requires a password and if
       
   385  * the user has the password for the post. If not then it will return before
       
   386  * displaying.
       
   387  *
       
   388  * Also uses the function get_post_custom() to get the post's 'enclosure'
       
   389  * metadata field and parses the value to display the enclosure(s). The
       
   390  * enclosure(s) consist of enclosure HTML tag(s) with a URI and other
       
   391  * attributes.
       
   392  *
       
   393  * @package WordPress
       
   394  * @subpackage Template
       
   395  * @since 1.5.0
       
   396  * @uses apply_filters() Calls 'rss_enclosure' hook on rss enclosure.
       
   397  * @uses get_post_custom() To get the current post enclosure metadata.
       
   398  */
       
   399 function rss_enclosure() {
       
   400 	if ( post_password_required() )
       
   401 		return;
       
   402 
       
   403 	foreach ( (array) get_post_custom() as $key => $val) {
       
   404 		if ($key == 'enclosure') {
       
   405 			foreach ( (array) $val as $enc ) {
       
   406 				$enclosure = explode("\n", $enc);
       
   407 
       
   408 				//only get the the first element eg, audio/mpeg from 'audio/mpeg mpga mp2 mp3'
       
   409 				$t = preg_split('/[ \t]/', trim($enclosure[2]) );
       
   410 				$type = $t[0];
       
   411 
       
   412 				echo apply_filters('rss_enclosure', '<enclosure url="' . trim(htmlspecialchars($enclosure[0])) . '" length="' . trim($enclosure[1]) . '" type="' . $type . '" />' . "\n");
       
   413 			}
       
   414 		}
       
   415 	}
       
   416 }
       
   417 
       
   418 /**
       
   419  * Display the atom enclosure for the current post.
       
   420  *
       
   421  * Uses the global $post to check whether the post requires a password and if
       
   422  * the user has the password for the post. If not then it will return before
       
   423  * displaying.
       
   424  *
       
   425  * Also uses the function get_post_custom() to get the post's 'enclosure'
       
   426  * metadata field and parses the value to display the enclosure(s). The
       
   427  * enclosure(s) consist of link HTML tag(s) with a URI and other attributes.
       
   428  *
       
   429  * @package WordPress
       
   430  * @subpackage Template
       
   431  * @since 2.2.0
       
   432  * @uses apply_filters() Calls 'atom_enclosure' hook on atom enclosure.
       
   433  * @uses get_post_custom() To get the current post enclosure metadata.
       
   434  */
       
   435 function atom_enclosure() {
       
   436 	if ( post_password_required() )
       
   437 		return;
       
   438 
       
   439 	foreach ( (array) get_post_custom() as $key => $val ) {
       
   440 		if ($key == 'enclosure') {
       
   441 			foreach ( (array) $val as $enc ) {
       
   442 				$enclosure = split("\n", $enc);
       
   443 				echo apply_filters('atom_enclosure', '<link href="' . trim(htmlspecialchars($enclosure[0])) . '" rel="enclosure" length="' . trim($enclosure[1]) . '" type="' . trim($enclosure[2]) . '" />' . "\n");
       
   444 			}
       
   445 		}
       
   446 	}
       
   447 }
       
   448 
       
   449 /**
       
   450  * Determine the type of a string of data with the data formatted.
       
   451  *
       
   452  * Tell whether the type is text, html, or xhtml, per RFC 4287 section 3.1.
       
   453  *
       
   454  * In the case of WordPress, text is defined as containing no markup,
       
   455  * xhtml is defined as "well formed", and html as tag soup (i.e., the rest).
       
   456  *
       
   457  * Container div tags are added to xhtml values, per section 3.1.1.3.
       
   458  *
       
   459  * @link http://www.atomenabled.org/developers/syndication/atom-format-spec.php#rfc.section.3.1
       
   460  *
       
   461  * @package WordPress
       
   462  * @subpackage Feed
       
   463  * @since 2.5
       
   464  *
       
   465  * @param string $data Input string
       
   466  * @return array array(type, value)
       
   467  */
       
   468 function prep_atom_text_construct($data) {
       
   469 	if (strpos($data, '<') === false && strpos($data, '&') === false) {
       
   470 		return array('text', $data);
       
   471 	}
       
   472 
       
   473 	$parser = xml_parser_create();
       
   474 	xml_parse($parser, '<div>' . $data . '</div>', true);
       
   475 	$code = xml_get_error_code($parser);
       
   476 	xml_parser_free($parser);
       
   477 
       
   478 	if (!$code) {
       
   479 		if (strpos($data, '<') === false) {
       
   480 			return array('text', $data);
       
   481 		} else {
       
   482 			$data = "<div xmlns='http://www.w3.org/1999/xhtml'>$data</div>";
       
   483 			return array('xhtml', $data);
       
   484 		}
       
   485 	}
       
   486 
       
   487 	if (strpos($data, ']]>') == false) {
       
   488 		return array('html', "<![CDATA[$data]]>");
       
   489 	} else {
       
   490 		return array('html', htmlspecialchars($data));
       
   491 	}
       
   492 }
       
   493 
       
   494 /**
       
   495  * Display the link for the currently displayed feed in a XSS safe way.
       
   496  *
       
   497  * Generate a correct link for the atom:self element.
       
   498  *
       
   499  * @package WordPress
       
   500  * @subpackage Feed
       
   501  * @since 2.5
       
   502  */
       
   503 function self_link() {
       
   504 	$host = @parse_url(get_option('home'));
       
   505 	$host = $host['host'];
       
   506 	echo esc_url(
       
   507 		'http'
       
   508 		. ( (isset($_SERVER['https']) && $_SERVER['https'] == 'on') ? 's' : '' ) . '://'
       
   509 		. $host
       
   510 		. stripslashes($_SERVER['REQUEST_URI'])
       
   511 		);
       
   512 }
       
   513 
       
   514 /**
       
   515  * Return the content type for specified feed type.
       
   516  *
       
   517  * @package WordPress
       
   518  * @subpackage Feed
       
   519  * @since 2.8.0
       
   520  */
       
   521 function feed_content_type( $type = '' ) {
       
   522 	if ( empty($type) )
       
   523 		$type = get_default_feed();
       
   524 
       
   525 	$types = array(
       
   526 		'rss'  => 'application/rss+xml',
       
   527 		'rss2' => 'application/rss+xml',
       
   528 		'rss-http'  => 'text/xml',
       
   529 		'atom' => 'application/atom+xml',
       
   530 		'rdf'  => 'application/rdf+xml'
       
   531 	);
       
   532 
       
   533 	$content_type = ( !empty($types[$type]) ) ? $types[$type] : 'application/octet-stream';
       
   534 
       
   535 	return apply_filters( 'feed_content_type', $content_type, $type );
       
   536 }
       
   537 
       
   538 /**
       
   539  * Build SimplePie object based on RSS or Atom feed from URL.
       
   540  *
       
   541  * @since 2.8
       
   542  *
       
   543  * @param string $url URL to retrieve feed
       
   544  * @return WP_Error|SimplePie WP_Error object on failure or SimplePie object on success
       
   545  */
       
   546 function fetch_feed($url) {
       
   547 	require_once (ABSPATH . WPINC . '/class-feed.php');
       
   548 
       
   549 	$feed = new SimplePie();
       
   550 	$feed->set_feed_url($url);
       
   551 	$feed->set_cache_class('WP_Feed_Cache');
       
   552 	$feed->set_file_class('WP_SimplePie_File');
       
   553 	$feed->set_cache_duration(apply_filters('wp_feed_cache_transient_lifetime', 43200));
       
   554 	$feed->init();
       
   555 	$feed->handle_content_type();
       
   556 
       
   557 	if ( $feed->error() )
       
   558 		return new WP_Error('simplepie-error', $feed->error());
       
   559 
       
   560 	return $feed;
       
   561 }