shimmie2/ext/sitemap/main.php

<?php

/*
 * Name: XML Sitemap
 * Author: Sein Kraft <mail@seinkraft.info>
 * Author: Drudex Software <support@drudexsoftware.com>
 * Link: http://drudexsoftware.com
 * License: GPLv2
 * Description: Sitemap with caching & advanced priorities
 * Documentation:
 */

class XMLSitemap extends Extension
{
	private $sitemap_queue = "";
	private $sitemap_filepath = ""; // set onPageRequest

	public function onPageRequest(PageRequestEvent $event)
	{
		if ($event->page_matches("sitemap.xml")) {
			global $config;

			$this->sitemap_filepath = data_path("cache/sitemap.xml");
			// determine if new sitemap needs to be generated
			if ($this->new_sitemap_needed()) {
				// determine which type of sitemap to generate
				if ($config->get_bool("sitemap_generatefull", false)) {
					$this->handle_full_sitemap(); // default false until cache fixed
				} else {
					$this->handle_smaller_sitemap();
				}
			} else $this->display_existing_sitemap();
		}
	}

	public function onSetupBuilding(SetupBuildingEvent $event)
	{
		$sb = new SetupBlock("Sitemap");

		$sb->add_bool_option("sitemap_generatefull", "Generate full sitemap");
		$sb->add_label("<br>(Enabled: every image and tag in sitemap, generation takes longer)");
		$sb->add_label("<br>(Disabled: only display the last 50 uploads in the sitemap)");

		$event->panel->add_block($sb);
	}

	// sitemap with only the latest 50 images
	private function handle_smaller_sitemap()
	{
		/* --- Add latest images to sitemap with higher priority --- */
		$latestimages = Image::find_images(0, 50, array());
		if(empty($latestimages)) return;
		$latestimages_urllist = array();
		foreach ($latestimages as $arrayid => $image) {
			// create url from image id's
			$latestimages_urllist[$arrayid] = "post/view/$image->id";
		}

		$this->add_sitemap_queue($latestimages_urllist, "monthly", "0.8", date("Y-m-d", strtotime($image->posted)));

		/* --- Display page --- */
		// when sitemap is ok, display it from the file
		$this->generate_display_sitemap();
	}

	// Full sitemap
	private function handle_full_sitemap()
	{
		global $database, $config;

		// add index
		$index = array();
		$index[0] = $config->get_string("front_page");
		$this->add_sitemap_queue($index, "weekly", "1");

		/* --- Add 20 most used tags --- */
		$popular_tags = $database->get_all("SELECT tag, count FROM tags ORDER BY `count` DESC LIMIT 0,20");
		foreach ($popular_tags as $arrayid => $tag) {
			$tag = $tag['tag'];
			$popular_tags[$arrayid] = "post/list/$tag/";
		}
		$this->add_sitemap_queue($popular_tags, "monthly", "0.9" /* not sure how to deal with date here */);

		/* --- Add latest images to sitemap with higher priority --- */
		$latestimages = Image::find_images(0, 50, array());
		$latestimages_urllist = array();
		foreach ($latestimages as $arrayid => $image) {
			// create url from image id's
			$latestimages_urllist[$arrayid] = "post/view/$image->id";
		}
		$this->add_sitemap_queue($latestimages_urllist, "monthly", "0.8", date("Y-m-d", strtotime($image->posted)));

		/* --- Add other tags --- */
		$other_tags = $database->get_all("SELECT tag, count FROM tags ORDER BY `count` DESC LIMIT 21,10000000");
		foreach ($other_tags as $arrayid => $tag) {
			$tag = $tag['tag'];
			// create url from tags (tagme ignored)
			if ($tag != "tagme")
				$other_tags[$arrayid] = "post/list/$tag/";
		}
		$this->add_sitemap_queue($other_tags, "monthly", "0.7" /* not sure how to deal with date here */);

		/* --- Add all other images to sitemap with lower priority --- */
		$otherimages = Image::find_images(51, 10000000, array());
		foreach ($otherimages as $arrayid => $image) {
			// create url from image id's
			$otherimages[$arrayid] = "post/view/$image->id";
		}
		$this->add_sitemap_queue($otherimages, "monthly", "0.6", date("Y-m-d", strtotime($image->posted)));


		/* --- Display page --- */
		// when sitemap is ok, display it from the file
		$this->generate_display_sitemap();
	}

	/**
	 * Adds an array of urls to the sitemap with the given information.
	 *
	 * @param array $urls
	 * @param string $changefreq
	 * @param string $priority
	 * @param string $date
	 */
	private function add_sitemap_queue(array $urls, $changefreq = "monthly",
                                       $priority = "0.5", $date = "2013-02-01")
	{
		foreach ($urls as $url) {
			$link = make_http(make_link("$url"));
			$this->sitemap_queue .= "
                    <url>
                    <loc>$link</loc>
                    <lastmod>$date</lastmod>
                    <changefreq>$changefreq</changefreq>
                    <priority>$priority</priority>
                    </url>";
		}
	}

	// sets sitemap with entries in sitemap_queue
	private function generate_display_sitemap()
	{
		global $page;

		$xml = "<" . "?xml version=\"1.0\" encoding=\"utf-8\"?" . ">
				<urlset xmlns=\"http://www.sitemaps.org/schemas/sitemap/0.9\">
					$this->sitemap_queue
				</urlset>";

		// Generate new sitemap
		file_put_contents($this->sitemap_filepath, $xml);
		$page->set_mode("data");
		$page->set_type("application/xml");
		$page->set_data($xml);
	}

	/**
	 * Returns true if a new sitemap is needed.
	 *
	 * @return bool
	 */
	private function new_sitemap_needed()
	{
		if(!file_exists($this->sitemap_filepath)) {
			return true;
		}

		$sitemap_generation_interval = 86400; // allow new site map every day
		$last_generated_time = filemtime($this->sitemap_filepath);

		// if file doesn't exist, return true
		if ($last_generated_time == false) {
			return true;
		}

		// if it's been a day since last sitemap creation, return true
		if ($last_generated_time + $sitemap_generation_interval < time()) {
			return true;
		} else {
			return false;
		}
	}

	private function display_existing_sitemap()
	{
		global $page;

		$xml = file_get_contents($this->sitemap_filepath);

		$page->set_mode("data");
		$page->set_type("application/xml");
		$page->set_data($xml);
	}
}