elasticsearch/action/indexing.php

<?php
/**
 * DokuWiki Plugin elasticsearch (Action Component)
 *
 * @license GPL 2 http://www.gnu.org/licenses/gpl-2.0.html
 * @author  Kieback&Peter IT <it-support@kieback-peter.de>
 * @author  Andreas Gohr <gohr@cosmocode.de>
 */

// must be run within Dokuwiki
if(!defined('DOKU_INC')) die();

class action_plugin_elasticsearch_indexing extends DokuWiki_Action_Plugin {

    /**
     * Registers a callback function for a given event
     *
     * @param Doku_Event_Handler $controller DokuWiki's event controller object
     * @return void
     */
    public function register(Doku_Event_Handler &$controller) {
        $controller->register_hook('TPL_CONTENT_DISPLAY', 'BEFORE', $this, 'handle_tpl_content_display');
    }

    /**
     * [Custom event handler which performs action]
     *
     * @param Doku_Event $event event object by reference
     * @param mixed $param [the parameters passed as fifth argument to register_hook() when this
     *                           handler was registered]
     * @return void
     */
    public function handle_tpl_content_display(Doku_Event &$event, $param) {
        global $ID, $INFO;
        $logs   = array();
        $logs[] = 'BEGIN content display';
        $logs[] = metaFN($ID, '.elasticsearch_indexed');
        $logs[] = wikiFN($ID);
        $logs[] = wikiFN($INFO['id']);
        $logs[] = $this->needs_indexing($ID) ? 'needs indexing' : 'no indexing needed';
        $logs[] = 'END content display';
        $this->log($logs);
        if($this->needs_indexing($ID)) {
            $this->index_page($ID);
        }
    }

    /**
     * Check if the page $id has changed since the last indexing.
     *
     * @param string $id
     * @return boolean
     */
    private function needs_indexing($id) {
        $indexStateFile = metaFN($id, '.elasticsearch_indexed');
        $dataFile       = wikiFN($id);

        // no data file -> no indexing
        if(!file_exists($dataFile)) {
            return false;
        }

        // force indexing if we're called via cli (e.g. cron)
        if(php_sapi_name() == 'cli') {
            return true;
        }
        // check if latest indexing attempt is done after page update
        if(file_exists($indexStateFile)) {
            if(filemtime($indexStateFile) > filemtime($dataFile)) {
                return false;
            }
        }
        return true;
    }

    /**
     * Save indexed state for a page
     *
     * @param string $id
     * @return int
     */
    private function update_indexstate($id) {
        $indexStateFile = metaFN($id, '.elasticsearch_indexed');
        return file_put_contents($indexStateFile, '');
    }

    /**
     * Index a page
     *
     * @param $id
     * @return void
     */
    public function index_page($id) {
        global $conf;

        /** @var helper_plugin_elasticsearch_client $hlp */
        $hlp = plugin_load('helper', 'elasticsearch_client');

        $this->log('Indexing page ' . $id);
        $indexName    = $this->getConf('indexname');
        $documentType = $this->getConf('documenttype');
        $client       = $hlp->connect();
        $index        = $client->getIndex($indexName);
        $type         = $index->getType($documentType);
        $documentId   = $documentType . '_' . $id;

        // @TODO check if content is empty, that means the page is deleted and
        //       has to be removed from the index.

        // collect the date which should be indexed
        $meta = p_get_metadata($id, '', true);

        $data             = array();
        $data['uri']      = $id;
        $data['created']  = date('Y-m-d\TH:i:s\Z', $meta['date']['created']);
        $data['modified'] = date('Y-m-d\TH:i:s\Z', $meta['date']['modified']);
        $data['creator']  = $meta['creator'];
        $data['title']    = $meta['title'];
        $data['abstract'] = $meta['description']['abstract'];
        $data['content']  = rawWiki($id);

        /** @var helper_plugin_translation $trans */
        $trans = plugin_load('helper', 'translation');
        if($trans) {
            // translation plugin available
            $lc = $trans->getLangPart($id);
            $data['language'] = $trans->realLC($lc);
        } else {
            // no translation plugin
            $lc = '';
            $data['language'] = $conf['lang'];
        }

        // fetching the top namespace's title
        $ids = explode(':', $id);
        if($lc) {
            $metadata_ns = p_get_metadata($ids[0] . ':' . $ids[1] . ':start', '', true);
        } else {
            $metadata_ns = p_get_metadata($ids[0] . ':start', '', true);
        }
        $data['namespace'] = $metadata_ns['title'];
        $data['namespace'] = str_replace('*', '', $data['namespace']);
        if(trim($data['namespace']) == '') {
            unset($data['namespace']);
        }

        // only index if we've found a namespace
        if(isset($data['namespace'])) {
            $data['groups'] = $this->getPageACL($id);

            // check if the document still exists to update it or add it as a new one
            try {
                $document = $type->getDocument($documentId);
                $client->updateDocument($documentId, array('doc' => $data), $index->getName(), $type->getName());
            } catch(\Elastica\Exception\NotFoundException $e) {
                $document = new \Elastica\Document($documentId, $data);
                $type->addDocument($document);
            }
            $index->refresh();
            $this->update_indexstate($id);
        }
    }

    /**
     * Log something to the debug log
     *
     * @param string $txt
     */
    private function log($txt) {
        if(!$this->getConf('debug')) {
            return;
        }
        if(!is_array($txt)) {
            $logs = array($txt);
        } else {
            $logs = $txt;
        }
        foreach($logs as $entry) {
            dbglog($entry);
        }
    }

    /**
     * Lists all groups that have at least read permissions on the given page
     *
     * @param $id
     * @return array
     */
    private function getPageACL($id) {
        global $AUTH_ACL;
        global $conf;

        $id    = cleanID($id);
        $ns    = getNS($id);
        $perms = array();

        $matches = preg_grep('/^' . preg_quote($id, '/') . '\s+/', $AUTH_ACL);
        if(count($matches)) {
            foreach($matches as $match) {
                $match = preg_replace('/#.*$/', '', $match); //ignore comments
                $acl   = preg_split('/\s+/', $match);
                if($acl[2] > AUTH_DELETE) $acl[2] = AUTH_DELETE; //no admins in the ACL!
                if(!isset($perms[$acl[1]])) $perms[$acl[1]] = $acl[2];
            }
        }
        //still here? do the namespace checks
        if($ns) {
            $path = $ns . ':\*';
        } else {
            $path = '\*'; //root document
        }
        do {
            $matches = preg_grep('/^' . $path . '\s+/', $AUTH_ACL);
            if(count($matches)) {
                foreach($matches as $match) {
                    $match = preg_replace('/#.*$/', '', $match); //ignore comments
                    $acl   = preg_split('/\s+/', $match);
                    if($acl[2] > AUTH_DELETE) $acl[2] = AUTH_DELETE; //no admins in the ACL!
                    if(!isset($perms[$acl[1]])) $perms[$acl[1]] = $acl[2];
                }
            }

            //get next higher namespace
            $ns = getNS($ns);

            if($path != '\*') {
                $path = $ns . ':\*';
                if($path == ':\*') $path = '\*';
            } else {
                //we did this already
                //break here
                break;
            }
        } while(1); //this should never loop endless
        $groups = array(str_replace('-', '', str_replace('@', '', strtolower(urldecode($conf['superuser'])))));
        foreach($perms as $group => $permission) {
            if($permission > AUTH_NONE) {
                $groups[] = str_replace('-', '', str_replace('@', '', strtolower(urldecode($group))));
                $this->log(sprintf("%s = %s", $group, $permission));
            }
        }
        return $groups;
    }
}