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Ticket #8405: feed.php

File feed.php, 14.2 KB (added by paulchenpanther, 5 years ago)
Line 
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 $show See get_bloginfo() for possible values.
26 * @return string
27 */
28function get_bloginfo_rss($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 $show See get_bloginfo() for possible values.
47 */
48function bloginfo_rss($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 */
65function 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 $sep Optional.How to separate the title. See wp_title() for more info.
79 * @return string Error message on failure or blog title on success.
80 */
81function get_wp_title_rss($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 $sep Optional.
99 */
100function wp_title_rss($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 */
114function 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 */
128function 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 $encode_html Optional. How to encode the content.
161 */
162function the_content_rss($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                $content = wp_specialchars($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 */
203function 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 */
216function 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 */
227function comment_guid() {
228        echo get_comment_guid();
229}
230
231/**
232 * Retrieve the feed GUID for the current comment.
233 *
234 * @package WordPress
235 * @subpackage Feed
236 * @since unknown
237 *
238 * @return bool|string false on failure or guid for comment on success.
239 */
240function get_comment_guid() {
241        global $comment;
242
243        if ( !is_object($comment) )
244                return false;
245
246        return get_the_guid($comment->comment_post_ID) . '#comment-' . $comment->comment_ID;
247}
248
249/**
250 * Display the link to the comments.
251 *
252 * @since 1.5.0
253 */
254function comment_link() {
255        echo htmlentities(get_comment_link());
256}
257
258/**
259 * Retrieve the current comment author for use in the feeds.
260 *
261 * @package WordPress
262 * @subpackage Feed
263 * @since 2.0.0
264 * @uses apply_filters() Calls 'comment_author_rss' hook on comment author.
265 * @uses get_comment_author()
266 *
267 * @return string Comment Author
268 */
269function get_comment_author_rss() {
270        return apply_filters('comment_author_rss', get_comment_author() );
271}
272
273/**
274 * Display the current comment author in the feed.
275 *
276 * @package WordPress
277 * @subpackage Feed
278 * @since 1.0.0
279 */
280function comment_author_rss() {
281        echo get_comment_author_rss();
282}
283
284/**
285 * Display the current comment content for use in the feeds.
286 *
287 * @package WordPress
288 * @subpackage Feed
289 * @since 1.0.0
290 * @uses apply_filters() Calls 'comment_text_rss' filter on comment content.
291 * @uses get_comment_text()
292 */
293function comment_text_rss() {
294        $comment_text = get_comment_text();
295        $comment_text = apply_filters('comment_text_rss', $comment_text);
296        echo $comment_text;
297}
298
299/**
300 * Retrieve all of the post categories, formatted for use in feeds.
301 *
302 * All of the categories for the current post in the feed loop, will be
303 * retrieved and have feed markup added, so that they can easily be added to the
304 * RSS2, Atom, or RSS1 and RSS0.91 RDF feeds.
305 *
306 * @package WordPress
307 * @subpackage Feed
308 * @since 2.1.0
309 * @uses apply_filters()
310 *
311 * @param string $type Optional, default is 'rss'. Either 'rss', 'atom', or 'rdf'.
312 * @return string All of the post categories for displaying in the feed.
313 */
314function get_the_category_rss($type = 'rss') {
315        $categories = get_the_category();
316        $tags = get_the_tags();
317        $the_list = '';
318        $cat_names = array();
319
320        $filter = 'rss';
321        if ( 'atom' == $type )
322                $filter = 'raw';
323
324        if ( !empty($categories) ) foreach ( (array) $categories as $category ) {
325                $cat_names[] = sanitize_term_field('name', $category->name, $category->term_id, 'category', $filter);
326        }
327
328        if ( !empty($tags) ) foreach ( (array) $tags as $tag ) {
329                $cat_names[] = sanitize_term_field('name', $tag->name, $tag->term_id, 'post_tag', $filter);
330        }
331
332        $cat_names = array_unique($cat_names);
333
334        foreach ( $cat_names as $cat_name ) {
335                if ( 'rdf' == $type )
336                        $the_list .= "\n\t\t<dc:subject><![CDATA[$cat_name]]></dc:subject>\n";
337                elseif ( 'atom' == $type )
338                        $the_list .= sprintf( '<category scheme="%1$s" term="%2$s" />', attribute_escape( apply_filters( 'get_bloginfo_rss', get_bloginfo( 'url' ) ) ), attribute_escape( $cat_name ) );
339                else
340                        $the_list .= "\n\t\t<category><![CDATA[" . html_entity_decode( $cat_name ) . "]]></category>\n";
341        }
342
343        return apply_filters('the_category_rss', $the_list, $type);
344}
345
346/**
347 * Display the post categories in the feed.
348 *
349 * @package WordPress
350 * @subpackage Feed
351 * @since 0.71
352 * @see get_the_category_rss() For better explanation.
353 *
354 * @param string $type Optional, default is 'rss'. Either 'rss', 'atom', or 'rdf'.
355 */
356function the_category_rss($type = 'rss') {
357        echo get_the_category_rss($type);
358}
359
360/**
361 * Display the HTML type based on the blog setting.
362 *
363 * The two possible values are either 'xhtml' or 'html'.
364 *
365 * @package WordPress
366 * @subpackage Feed
367 * @since 2.2.0
368 */
369function html_type_rss() {
370        $type = get_bloginfo('html_type');
371        if (strpos($type, 'xhtml') !== false)
372                $type = 'xhtml';
373        else
374                $type = 'html';
375        echo $type;
376}
377
378/**
379 * Display the rss enclosure for the current post.
380 *
381 * Uses the global $post to check whether the post requires a password and if
382 * the user has the password for the post. If not then it will return before
383 * displaying.
384 *
385 * Also uses the function get_post_custom() to get the post's 'enclosure'
386 * metadata field and parses the value to display the enclosure(s). The
387 * enclosure(s) consist of enclosure HTML tag(s) with a URI and other
388 * attributes.
389 *
390 * @package WordPress
391 * @subpackage Template
392 * @since 1.5.0
393 * @uses apply_filters() Calls 'rss_enclosure' hook on rss enclosure.
394 * @uses get_post_custom() To get the current post enclosure metadata.
395 */
396function rss_enclosure() {
397        if ( post_password_required() )
398                return;
399
400        foreach ( (array) get_post_custom() as $key => $val) {
401                if ($key == 'enclosure') {
402                        foreach ( (array) $val as $enc ) {
403                                $enclosure = split("\n", $enc);
404
405                                //only get the the first element eg, audio/mpeg from 'audio/mpeg mpga mp2 mp3'
406                                $t = split('[ \t]', trim($enclosure[2]) );
407                                $type = $t[0];
408
409                                echo apply_filters('rss_enclosure', '<enclosure url="' . trim(htmlspecialchars($enclosure[0])) . '" length="' . trim($enclosure[1]) . '" type="' . $type . '" />' . "\n");
410                        }
411                }
412        }
413}
414
415/**
416 * Display the atom enclosure for the current post.
417 *
418 * Uses the global $post to check whether the post requires a password and if
419 * the user has the password for the post. If not then it will return before
420 * displaying.
421 *
422 * Also uses the function get_post_custom() to get the post's 'enclosure'
423 * metadata field and parses the value to display the enclosure(s). The
424 * enclosure(s) consist of link HTML tag(s) with a URI and other attributes.
425 *
426 * @package WordPress
427 * @subpackage Template
428 * @since 2.2.0
429 * @uses apply_filters() Calls 'atom_enclosure' hook on atom enclosure.
430 * @uses get_post_custom() To get the current post enclosure metadata.
431 */
432function atom_enclosure() {
433        if ( post_password_required() )
434                return;
435
436        foreach ( (array) get_post_custom() as $key => $val ) {
437                if ($key == 'enclosure') {
438                        foreach ( (array) $val as $enc ) {
439                                $enclosure = split("\n", $enc);
440                                echo apply_filters('atom_enclosure', '<link href="' . trim(htmlspecialchars($enclosure[0])) . '" rel="enclosure" length="' . trim($enclosure[1]) . '" type="' . trim($enclosure[2]) . '" />' . "\n");
441                        }
442                }
443        }
444}
445
446/**
447 * Determine the type of a string of data with the data formatted.
448 *
449 * Tell whether the type is text, html, or xhtml, per RFC 4287 section 3.1.
450 *
451 * In the case of WordPress, text is defined as containing no markup,
452 * xhtml is defined as "well formed", and html as tag soup (i.e., the rest).
453 *
454 * Container div tags are added to xhtml values, per section 3.1.1.3.
455 *
456 * @link http://www.atomenabled.org/developers/syndication/atom-format-spec.php#rfc.section.3.1
457 *
458 * @package WordPress
459 * @subpackage Feed
460 * @since 2.5
461 *
462 * @param string $data Input string
463 * @return array array(type, value)
464 */
465function prep_atom_text_construct($data) {
466        if (strpos($data, '<') === false && strpos($data, '&') === false) {
467                return array('text', $data);
468        }
469
470        $parser = xml_parser_create();
471        xml_parse($parser, '<div>' . $data . '</div>', true);
472        $code = xml_get_error_code($parser);
473        xml_parser_free($parser);
474
475        if (!$code) {
476                if (strpos($data, '<') === false) {
477                        return array('text', $data);
478                } else {
479                        $data = "<div xmlns='http://www.w3.org/1999/xhtml'>$data</div>";
480                        return array('xhtml', $data);
481                }
482        }
483
484        if (strpos($data, ']]>') == false) {
485                return array('html', "<![CDATA[$data]]>");
486        } else {
487                return array('html', htmlspecialchars($data));
488        }
489}
490
491/**
492 * Display the link for the currently displayed feed in a XSS safe way.
493 *
494 * Generate a correct link for the atom:self element.
495 *
496 * @package WordPress
497 * @subpackage Feed
498 * @since 2.5
499 */
500function self_link() {
501        $host = @parse_url(get_option('home'));
502        $host = $host['host'];
503        echo clean_url(
504                'http'
505                . ( (isset($_SERVER['https']) && $_SERVER['https'] == 'on') ? 's' : '' ) . '://'
506                . $host
507                . stripslashes($_SERVER['REQUEST_URI'])
508                );
509}
510
511?>