shimmie2/ext/rss_comments/main.php

<?php
/*
 * Name: RSS for Comments
 * Author: Shish <webmaster@shishnet.org>
 * Link: http://code.shishnet.org/shimmie2/
 * License: GPLv2
 * Description: Self explanatory
 */

class RSS_Comments extends Extension {
	protected $db_support = ['mysql', 'sqlite'];  // pgsql has no UNIX_TIMESTAMP

	public function onPostListBuilding(PostListBuildingEvent $event) {
		global $config, $page;
		$title = $config->get_string('title');

		$page->add_html_header("<link rel=\"alternate\" type=\"application/rss+xml\" ".
			"title=\"$title - Comments\" href=\"".make_link("rss/comments")."\" />");
	}

	public function onPageRequest(PageRequestEvent $event) {
		global $config, $database, $page;
		if($event->page_matches("rss/comments")) {
			$page->set_mode("data");
			$page->set_type("application/rss+xml");

			$comments = $database->get_all("
				SELECT
					users.id as user_id, users.name as user_name,
					comments.comment as comment, comments.id as comment_id,
					comments.image_id as image_id, comments.owner_ip as poster_ip,
					comments.posted as posted
				FROM comments
				LEFT JOIN users ON comments.owner_id=users.id
			  	ORDER BY comments.id DESC
		  		LIMIT 10
			");

			$data = "";
			foreach($comments as $comment) {
				$image_id = $comment['image_id'];
				$comment_id = $comment['comment_id'];
				$link = make_http(make_link("post/view/$image_id"));
				$owner = html_escape($comment['user_name']);
				$posted = date(DATE_RSS, strtotime($comment['posted']));
				$comment = html_escape($comment['comment']);
				$content = html_escape("$owner: $comment");

				$data .= "
					<item>
						<title>$owner comments on $image_id</title>
						<link>$link</link>
						<guid isPermaLink=\"false\">$comment_id</guid>
						<pubDate>$posted</pubDate>
						<description>$content</description>
					</item>
				";
			}

			$title = $config->get_string('title');
			$base_href = make_http(get_base_href());
			$version = $config->get_string('version');
			$xml = <<<EOD
<?xml version="1.0" encoding="utf-8" ?>
<rss version="2.0">
	<channel>
		<title>$title</title>
		<description>The latest comments on the image board</description>
		<link>$base_href</link>
		<generator>$version</generator>
		<copyright>(c) 2007 Shish</copyright>
		$data
	</channel>
</rss>
EOD;
			$page->set_data($xml);
		}
	}
}