silverstripe-googlesitemaps/code/GoogleSitemap.php

<?php

use SilverStripe\CMS\Model\SiteTree;
use SilverStripe\Control\Director;
use SilverStripe\Core\ClassInfo;
use SilverStripe\Core\Config\Config;
use SilverStripe\Core\Object;
use SilverStripe\ORM\ArrayList;
use SilverStripe\ORM\DataList;
use SilverStripe\ORM\Versioning\Versioned;
use SilverStripe\View\ArrayData;

/**
 * Sitemaps are a way to tell Google about pages on your site that they might
 * not otherwise discover. In its simplest terms, a XML Sitemap usually called
 * a Sitemap, with a capital S—is a list of the pages on your website.
 *
 * Creating and submitting a Sitemap helps make sure that Google knows about
 * all the  pages on your site, including URLs that may not be discoverable by
 * Google's normal crawling process.
 *
 * The GoogleSitemap handle requests to 'sitemap.xml'
 * the other two classes are used to render the sitemap.
 *
 * You can notify ("ping") Google about a changed sitemap
 * automatically whenever a new page is published or unpublished.
 * By default, Google is not notified, and will pick up your new
 * sitemap whenever the GoogleBot visits your website.
 *
 * To Enable notification of Google after every publish set google_notification_enabled
 * to true in the googlesitemaps.yml config file.
 * This file is usually located in the _config folder of your project folder.
 * e.g mysite/_config/googlesitemaps.yml
 *
 * <example>
 *	---
 *	Name: customgooglesitemaps
 *	After: googlesitemaps
 *	---
 *	GoogleSitemap:
 * 		enabled: true
 * 		objects_per_sitemap: 1000
 * 		google_notification_enabled: true
 * 		use_show_in_search: true
 * </example>
 *
 * @see http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=34609
 *
 * @package googlesitemaps
 */
class GoogleSitemap extends Object
{

    /**
     * List of {@link DataObject} class names to include. As well as the change
     * frequency and priority of each class.
     *
     * @var array
     */
    private static $dataobjects = array();

    /**
     * List of custom routes to include in the sitemap (such as controller
     * subclasses) as well as the change frequency and priority.
     *
     * @var array
     */
    private static $routes = array();

    /**
     * @config
     *
     * @var boolean
     */
    private static $exclude_redirector_pages = true;

    /**
     * Decorates the given DataObject with {@link GoogleSitemapDecorator}
     * and pushes the class name to the registered DataObjects.
     * Note that all registered DataObjects need the method AbsoluteLink().
     *
     * @param string $className  name of DataObject to register
     * @param string $changeFreq how often is this DataObject updated?
     *                           Possible values:
     *                           always, hourly, daily, weekly, monthly, yearly, never
     * @param string $priority   How important is this DataObject in comparison to other urls?
     *                           Possible values: 0.1, 0.2 ... , 0.9, 1.0
     *
     * @return void
     */
    public static function register_dataobject($className, $changeFreq = 'monthly', $priority = '0.6')
    {
        if (!self::is_registered($className)) {
            $className::add_extension('GoogleSitemapExtension');

            self::$dataobjects[$className] = array(
                'frequency' => ($changeFreq) ? $changeFreq : 'monthly',
                'priority' => ($priority) ? $priority : '0.6'
            );
        }
    }

    /**
     * Registers multiple dataobjects in a single line. See {@link register_dataobject}
     * for the heavy lifting
     *
     * @param array $dataobjects array of class names of DataObject to register
     * @param string $changeFreq how often is this DataObject updated?
     *                           Possible values:
     *                           always, hourly, daily, weekly, monthly, yearly, never
     * @param string $priority   How important is this DataObject in comparison to other urls?
     *                           Possible values: 0.1, 0.2 ... , 0.9, 1.0
     *
     * @return void
     */
    public static function register_dataobjects($dataobjects, $changeFreq = 'monthly', $priority = '0.6')
    {
        foreach ($dataobjects as $obj) {
            self::register_dataobject($obj, $changeFreq, $priority);
        }
    }

    /**
     * Checks whether the given class name is already registered or not.
     *
     * @param string $className Name of DataObject to check
     *
     * @return bool
     */
    public static function is_registered($className)
    {
        if (!isset(self::$dataobjects[$className])) {
            $lowerKeys = array_change_key_case(self::$dataobjects);

            return isset($lowerKeys[$className]);
        }

        return true;
    }

    /**
     * Unregisters a class from the sitemap. Mostly used for the test suite
     *
     * @param string
     */
    public static function unregister_dataobject($className)
    {
        unset(self::$dataobjects[$className]);
    }

    /**
     * Clears registered {@link DataObjects}. Useful for unit tests.
     *
     * @return void
     */
    public static function clear_registered_dataobjects()
    {
        self::$dataobjects = array();
    }

    /**
     * Register a given route to the sitemap list
     *
     * @param string
     * @param string
     * @param string
     *
     * @return void
     */
    public static function register_route($route, $changeFreq = 'monthly', $priority = '0.6')
    {
        self::$routes = array_merge(self::$routes, array(
            $route => array(
                'frequency' => ($changeFreq) ? $changeFreq : 'monthly',
                'priority' => ($priority) ? $priority : '0.6'
            )
        ));
    }

    /**
     * Registers a given list of relative urls. Will be merged with the current
     * registered routes. If you want to replace them, please call {@link clear_routes}
     *
     * @param array
     * @param string
     * @param string
     *
     * @return void
     */
    public static function register_routes($routes, $changeFreq = 'monthly', $priority = '0.6')
    {
        foreach ($routes as $route) {
            self::register_route($route, $changeFreq, $priority);
        }
    }

    /**
     * Clears registered routes
     *
     * @return void
     */
    public static function clear_registered_routes()
    {
        self::$routes = array();
    }

    /**
     * Constructs the list of data to include in the rendered sitemap. Links
     * can include pages from the website, dataobjects (such as forum posts)
     * as well as custom registered paths.
     *
     * @param string
     * @param int
     *
     * @return ArrayList
     */
    public function getItems($class, $page = 1)
    {
        //normalise the class name
        try {
            $reflectionClass = new ReflectionClass($class);
            $class = $reflectionClass->getName();
        } catch (ReflectionException $e) {
            // this can happen when $class is GoogleSitemapRoute
            //we should try to carry on
        }

        $output = new ArrayList();
        $count = Config::inst()->get('GoogleSitemap', 'objects_per_sitemap');
        $filter =  Config::inst()->get('GoogleSitemap', 'use_show_in_search');
        $redirector =  Config::inst()->get('GoogleSitemap', 'exclude_redirector_pages');

        // todo migrate to extension hook or DI point for other modules to
        // modify state filters
        if (class_exists('Translatable')) {
            Translatable::disable_locale_filter();
        }

        if ($class == SiteTree::class) {
            $instances = Versioned::get_by_stage(SiteTree::class, 'Live');

            if($filter) {
                $instances = $instances->filter('ShowInSearch', 1);
            }

            if($redirector) {
                foreach (ClassInfo::subclassesFor('RedirectorPage') as $redirectorClass) {
                    $instances = $instances->exclude('ClassName', $redirectorClass);
                }
            }
        } elseif ($class == "GoogleSitemapRoute") {
            $instances = array_slice(self::$routes, ($page - 1) * $count, $count);
            $output = new ArrayList();

            if ($instances) {
                foreach ($instances as $route => $config) {
                    $output->push(new ArrayData(array(
                        'AbsoluteLink' => Director::absoluteURL($route),
                        'ChangeFrequency' => $config['frequency'],
                        'GooglePriority' => $config['priority']
                    )));
                }
            }

            return $output;
        } else {
            $instances = new DataList($class);
        }

        $this->extend("alterDataList", $instances, $class);

        $instances = $instances->limit(
            $count,
            ($page - 1) * $count
        );

        if ($instances) {
            foreach ($instances as $obj) {
                if ($obj->canIncludeInGoogleSitemap()) {
                    $output->push($obj);
                }
            }
        }

        return $output;
    }

    /**
     * Static interface to instance level ->getItems() for backward compatibility.
     *
     * @param string
     * @param int
     *
     * @return ArrayList
     * @deprecated Please create an instance and call ->getSitemaps() instead.
     */
    public static function get_items($class, $page = 1)
    {
        return static::inst()->getItems($class, $page);
    }


    /**
     * Returns the string frequency of edits for a particular dataobject class.
     *
     * Frequency for {@link SiteTree} objects can be determined from the version
     * history.
     *
     * @param string
     *
     * @return string
     */
    public static function get_frequency_for_class($class)
    {
        foreach (self::$dataobjects as $type => $config) {
            if ($class == $type) {
                return $config['frequency'];
            }
        }

        return '';
    }

    /**
     * Returns the default priority of edits for a particular dataobject class.
     *
     * @param string
     *
     * @return float
     */
    public static function get_priority_for_class($class)
    {
        foreach (self::$dataobjects as $type => $config) {
            if ($class == $type) {
                return $config['priority'];
            }
        }

        return 0.5;
    }

    /**
     * The google site map is broken down into multiple smaller files to
     * prevent overbearing a server. By default separate {@link DataObject}
     * records are keep in separate files and broken down into chunks.
     *
     * @return ArrayList
     */
    public function getSitemaps()
    {
        $countPerFile = Config::inst()->get('GoogleSitemap', 'objects_per_sitemap');
        $sitemaps = new ArrayList();
        $filter = Config::inst()->get('GoogleSitemap', 'use_show_in_search');

        if (class_exists(SiteTree::class)) {
            // move to extension hook. At the moment moduleexists config hook
            // does not work.
            if (class_exists('Translatable')) {
                Translatable::disable_locale_filter();
            }

            $filter = ($filter) ? "\"ShowInSearch\" = 1" : "";
            $class = SiteTree::class;
            $instances = Versioned::get_by_stage($class, 'Live', $filter);
            $this->extend("alterDataList", $instances, $class);
            $count = $instances->count();

            $neededForPage = ceil($count / $countPerFile);

            for ($i = 1; $i <= $neededForPage; $i++) {
                $lastEdited = $instances
                    ->limit($countPerFile, ($i - 1) * $countPerFile)
                    ->sort(array())
                    ->max('LastEdited');

                $lastModified = ($lastEdited) ? date('Y-m-d', strtotime($lastEdited)) : date('Y-m-d');

                $sitemaps->push(new ArrayData(array(
                    'ClassName' => $this->sanitiseClassName(SiteTree::class),
                    'LastModified' => $lastModified,
                    'Page' => $i
                )));
            }
        }

        if (count(self::$dataobjects) > 0) {
            foreach (self::$dataobjects as $class => $config) {
                $list = new DataList($class);
                $list = $list->sort('LastEdited ASC');
                $this->extend("alterDataList", $list, $class);
                $neededForClass = ceil($list->count() / $countPerFile);

                for ($i = 1; $i <= $neededForClass; $i++) {
                    // determine the last modified date for this slice
                    $sliced = $list
                        ->limit($countPerFile, ($i - 1) * $countPerFile)
                        ->last();

                    $lastModified = ($sliced) ? $sliced->dbObject('LastEdited')->Format('Y-m-d') : date('Y-m-d');

                    $sitemaps->push(new ArrayData(array(
                        'ClassName' => $this->sanitiseClassName($class),
                        'Page' => $i,
                        'LastModified' => $lastModified
                    )));
                }
            }
        }

        if (count(self::$routes) > 0) {
            $needed = ceil(count(self::$routes) / $countPerFile);

            for ($i = 1; $i <= $needed; $i++) {
                $sitemaps->push(new ArrayData(array(
                    'ClassName' => 'GoogleSitemapRoute',
                    'Page' => $i
                )));
            }
        }

        return $sitemaps;
    }

    /**
     * Static interface to instance level ->getSitemaps() for backward compatibility.
     *
     * @return ArrayList
     * @deprecated Please create an instance and call ->getSitemaps() instead.
     */
    public static function get_sitemaps()
    {
        return static::inst()->getSitemaps();
    }

    /**
     * Notifies Google about changes to your sitemap. This behavior is disabled
     * by default, to enable, read the documentation provided in the docs folder.
     *
     * After notifications have been enabled, every publish / unpublish of a page.
     * will notify Google of the update.
     *
     * If the site is in development mode no ping will be sent regardless whether
     * the Google notification is enabled.
     *
     * @return boolean
     */
    public static function ping()
    {
        if (!self::enabled()) {
            return false;
        }

        // Don't ping if the site has disabled it, or if the site is in dev mode
        $active = Config::inst()->get('GoogleSitemap', 'google_notification_enabled');

        if (!$active || Director::isDev()) {
            return false;
        }

        $location = urlencode(Controller::join_links(
            Director::absoluteBaseURL(),
            'sitemap.xml'
        ));

        $googleResponse = self::send_ping(
            "www.google.com", "/webmasters/sitemaps/ping", sprintf("sitemap=%s", $location)
        );

        // bing
        $bing = Config::inst()->get('GoogleSitemap', 'bing_notification_enabled');

        if($bing) {
            $bingResponse = self::send_ping(
                "www.bing.com", "/ping", sprintf("sitemap=%s", $location)
            );
        }

        return true;
    }

    /**
     * Send an HTTP request to the host.
     *
     * @return String Response text
     */
    protected static function send_ping($host, $path, $query)
    {
        $socket = fsockopen($host, 80, $errno, $error);
        if (!$socket) {
            return $error;
        }
        if ($query) {
            $query = '?' . $query;
        }
        $request = "GET {$path}{$query} HTTP/1.1\r\nHost: $host\r\nConnection: Close\r\n\r\n";
        fwrite($socket, $request);
        $response = stream_get_contents($socket);

        return $response;
    }

    /**
     * Is GoogleSitemap enabled?
     *
     * @return boolean
     */
    public static function enabled()
    {
        return (Config::inst()->get('GoogleSitemap', 'enabled', Config::INHERITED));
    }


    /**
     * Convenience method for manufacturing an instance for hew instance-level
     * methods (and for easier type definition).
     *
     * @return GoogleSitemap
     */
    public static function inst()
    {
        return GoogleSitemap::create();
    }

    /**
     * Sanitise a namespaced class' name for inclusion in a link
     * @return string
     */
    protected function sanitiseClassName($class)
    {
        return str_replace('\\', '-', $class);
    }
}