xhtml-compiler/XHTMLCompiler/DOMFilter/RSSGenerator.php

   1 <?php
   2
   3 class XHTMLCompiler_DOMFilter_RSSGenerator extends XHTMLCompiler_DOMFilter
   4 {
   5
   6     protected $name = 'RSSGenerator';
   7     protected $prefix = 'rss';
   8
   9     // new namespace defines the following attributes:
  10     // for - IDREF to an element where we are to get the RSS info from
  11
  12     public function process(DOMDocument $dom, $page, $manager) {
  13
  14         // attempt to find declarations of the namespace
  15         $nodes = $this->query(
  16             "//attribute::*[namespace-uri() = '".$this->ns."']"
  17         );
  18         if (!$nodes->length) return;
  19
  20         // grab the document's links to RSS feeds
  21         // we require that the link have a href, a title and a type
  22         // as well as an rss:for attribute specifying where to grab data
  23         $links = $this->query('//html:link[@rss:for]');
  24
  25         foreach ($links as $link) {
  26             $this->generateRSS($dom, $link, $page);
  27         }
  28
  29     }
  30
  31     /**
  32      * Generates the RSS feed for a specific link in a document
  33      * @param $link <link> DOMElement we're generating feed for
  34      * @param $page Page we're generating for
  35      */
  36     protected function generateRSS($dom, $link, $page) {
  37         // get data from the document
  38         $location   = $link->getAttribute('href');
  39         $title      = $link->getAttribute('title');
  40         $path       = $page->getWebPath();
  41
  42         // remove specialized attributes
  43         $id          = $this->confiscateAttr($link, $this->ns, 'for');
  44         $description = $this->confiscateAttr($link, $this->ns, 'description');
  45
  46         $lang = $dom->documentElement->getAttribute('xml:lang');
  47
  48         $data_source = $dom->getElementById($id);
  49
  50         // setup the RSS feed
  51         $doc = new DOMDocument('1.0', 'UTF-8');
  52         $doc->formatOutput = true;
  53
  54         $rss = $doc->createElement('rss');
  55         $rss->setAttribute('version', '2.0');
  56         $doc->appendChild($rss);
  57
  58         $channel = $doc->createElement('channel');
  59         $rss->appendChild($channel);
  60
  61         $channel->appendChild($doc->createElement('title', $title));
  62         $channel->appendChild($doc->createElement('link', $path));
  63         if ($lang) $channel->appendChild($doc->createElement('language', $lang));
  64         if ($description) $channel->appendChild($doc->createElement('description', $description));
  65         $channel->appendChild($doc->createElement('generator', 'XHTML Compiler'));
  66
  67         // parse data source
  68         foreach ($data_source->childNodes as $src_item) {
  69             if (! $src_item instanceof DOMElement) continue;
  70             if ($src_item->getAttribute('class') !== 'item') continue;
  71
  72             $item = $doc->createElement('item');
  73             $channel->appendChild($item);
  74
  75             foreach ($src_item->childNodes as $element) {
  76                 if (! $element instanceof DOMElement) continue;
  77                 switch ($element->getAttribute('class')) {
  78                     case 'title':
  79                         $item->appendChild($doc->createElement('title',
  80                             $title=$element->textContent));
  81                         break;
  82                     case 'date':
  83                         $item->appendChild($doc->createElement('pubDate',
  84                             $element->textContent));
  85                         break;
  86                     case 'body':
  87                         $item->appendChild($doc->createElement('description',
  88                             $element->textContent));
  89                         break;
  90                 }
  91             }
  92
  93             $item_id = $src_item->getAttribute('id');
  94             if (!$item_id) {
  95                 trigger_error("News item '$title' has no ID");
  96                 continue;
  97             }
  98             $item->appendChild($doc->createElement('link', $path . '#' . $item_id));
  99
 100         }
 101
 102         // save the feed
 103         $doc->save($location);
 104         chmod($location, 0666);
 105
 106     }
 107
 108 }
 109
 110 ?>