ElggInstaller.php

Go to the documentation of this file.

<?php

class ElggInstaller {

    protected $steps = array(
        'welcome',
        'requirements',
        'database',
        'settings',
        'admin',
        'complete',
        );

    protected $status = array(
        'config' => FALSE,
        'database' => FALSE,
        'settings' => FALSE,
        'admin' => FALSE,
    );

    protected $isAction = FALSE;

    protected $autoLogin = TRUE;

    public function __construct() {
        // load ElggRewriteTester as we depend on it
        require_once(dirname(__FILE__) . "/ElggRewriteTester.php");

        $this->isAction = isset($_SERVER['REQUEST_METHOD']) && $_SERVER['REQUEST_METHOD'] === 'POST';

        $this->bootstrapConfig();

        $this->bootstrapEngine();

        _elgg_services()->setValue('session', new ElggSession(new Elgg_Http_MockSessionStorage()));

        elgg_set_viewtype('installation');

        set_error_handler('_elgg_php_error_handler');
        set_exception_handler('_elgg_php_exception_handler');

        register_translations(dirname(__FILE__) . '/languages/', TRUE);
    }

    public function run($step) {
        global $CONFIG;

        // language needs to be set before the first call to elgg_echo()
        $CONFIG->language = 'en';

        // check if this is a URL rewrite test coming in
        $this->processRewriteTest();

        if (!in_array($step, $this->getSteps())) {
            $msg = elgg_echo('InstallationException:UnknownStep', array($step));
            throw new InstallationException($msg);
        }

        $this->setInstallStatus();

        $this->checkInstallCompletion($step);

        // check if this is an install being resumed
        $this->resumeInstall($step);

        $this->finishBootstraping($step);

        $params = $this->getPostVariables();
        $this->$step($params);
    }

    public function setAutoLogin($flag) {
        $this->autoLogin = (bool) $flag;
    }

    public function batchInstall(array $params, $createHtaccess = FALSE) {
        global $CONFIG;

        restore_error_handler();
        restore_exception_handler();

        $defaults = array(
            'dbhost' => 'localhost',
            'dbprefix' => 'elgg_',
            'path' => $CONFIG->path,
            'language' => 'en',
            'siteaccess' => ACCESS_PUBLIC,
        );
        $params = array_merge($defaults, $params);

        $requiredParams = array(
            'dbuser',
            'dbpassword',
            'dbname',
            'sitename',
            'wwwroot',
            'dataroot',
            'displayname',
            'email',
            'username',
            'password',
        );
        foreach ($requiredParams as $key) {
            if (empty($params[$key])) {
                $msg = elgg_echo('install:error:requiredfield', array($key));
                throw new InstallationException($msg);
            }
        }

        // password is passed in once
        $params['password1'] = $params['password2'] = $params['password'];

        if ($createHtaccess) {
            $rewriteTester = new ElggRewriteTester();
            if (!$rewriteTester->createHtaccess($params['wwwroot'], $CONFIG->path)) {
                throw new InstallationException(elgg_echo('install:error:htaccess'));
            }
        }

        $this->setInstallStatus();

        if (!$this->status['config']) {
            if (!$this->createSettingsFile($params)) {
                throw new InstallationException(elgg_echo('install:error:settings'));
            }
        }

        if (!$this->connectToDatabase()) {
            throw new InstallationException(elgg_echo('install:error:databasesettings'));
        }

        if (!$this->status['database']) {
            if (!$this->installDatabase()) {
                throw new InstallationException(elgg_echo('install:error:cannotloadtables'));
            }
        }

        // load remaining core libraries
        $this->finishBootstraping('settings');

        if (!$this->saveSiteSettings($params)) {
            throw new InstallationException(elgg_echo('install:error:savesitesettings'));
        }

        if (!$this->createAdminAccount($params)) {
            throw new InstallationException(elgg_echo('install:admin:cannot_create'));
        }
    }

    protected function render($step, $vars = array()) {

        $vars['next_step'] = $this->getNextStep($step);

        $title = elgg_echo("install:$step");
        $body = elgg_view("install/pages/$step", $vars);
        echo elgg_view_page(
                $title,
                $body,
                'default',
                array(
                    'step' => $step,
                    'steps' => $this->getSteps(),
                    )
                );
        exit;
    }

    protected function welcome($vars) {
        $this->render('welcome');
    }

    protected function requirements($vars) {

        $report = array();

        // check PHP parameters and libraries
        $this->checkPHP($report);

        // check URL rewriting
        $this->checkRewriteRules($report);

        // check for existence of settings file
        if ($this->checkSettingsFile($report) != TRUE) {
            // no file, so check permissions on engine directory
            $this->checkEngineDir($report);
        }

        // check the database later
        $report['database'] = array(array(
            'severity' => 'info',
            'message' => elgg_echo('install:check:database')
        ));

        // any failures?
        $numFailures = $this->countNumConditions($report, 'failure');

        // any warnings
        $numWarnings = $this->countNumConditions($report, 'warning');


        $params = array(
            'report' => $report,
            'num_failures' => $numFailures,
            'num_warnings' => $numWarnings,
        );

        $this->render('requirements', $params);
    }

    protected function database($submissionVars) {

        $formVars = array(
            'dbuser' => array(
                'type' => 'text',
                'value' => '',
                'required' => TRUE,
                ),
            'dbpassword' => array(
                'type' => 'password',
                'value' => '',
                'required' => FALSE,
                ),
            'dbname' => array(
                'type' => 'text',
                'value' => '',
                'required' => TRUE,
                ),
            'dbhost' => array(
                'type' => 'text',
                'value' => 'localhost',
                'required' => TRUE,
                ),
            'dbprefix' => array(
                'type' => 'text',
                'value' => 'elgg_',
                'required' => TRUE,
                ),
        );

        if ($this->checkSettingsFile()) {
            // user manually created settings file so we fake out action test
            $this->isAction = TRUE;
        }

        if ($this->isAction) {
            do {
                // only create settings file if it doesn't exist
                if (!$this->checkSettingsFile()) {
                    if (!$this->validateDatabaseVars($submissionVars, $formVars)) {
                        // error so we break out of action and serve same page
                        break;
                    }

                    if (!$this->createSettingsFile($submissionVars)) {
                        break;
                    }
                }

                // check db version and connect
                if (!$this->connectToDatabase()) {
                    break;
                }

                if (!$this->installDatabase()) {
                    break;
                }

                system_message(elgg_echo('install:success:database'));

                $this->continueToNextStep('database');
            } while (FALSE);  // PHP doesn't support breaking out of if statements
        }

        $formVars = $this->makeFormSticky($formVars, $submissionVars);

        $params = array('variables' => $formVars,);

        if ($this->checkSettingsFile()) {
            // settings file exists and we're here so failed to create database
            $params['failure'] = TRUE;
        }

        $this->render('database', $params);
    }

    protected function settings($submissionVars) {
        global $CONFIG;

        $formVars = array(
            'sitename' => array(
                'type' => 'text',
                'value' => 'My New Community',
                'required' => TRUE,
                ),
            'siteemail' => array(
                'type' => 'email',
                'value' => '',
                'required' => FALSE,
                ),
            'wwwroot' => array(
                'type' => 'url',
                'value' => elgg_get_site_url(),
                'required' => TRUE,
                ),
            'path' => array(
                'type' => 'text',
                'value' => $CONFIG->path,
                'required' => TRUE,
                ),
            'dataroot' => array(
                'type' => 'text',
                'value' => '',
                'required' => TRUE,
                ),
            'siteaccess' => array(
                'type' => 'access',
                'value' =>  ACCESS_PUBLIC,
                'required' => TRUE,
                ),
        );

        // if Apache, we give user option of having Elgg create data directory
        //if (ElggRewriteTester::guessWebServer() == 'apache') {
        //  $formVars['dataroot']['type'] = 'combo';
        //  $CONFIG->translations['en']['install:settings:help:dataroot'] =
        //          $CONFIG->translations['en']['install:settings:help:dataroot:apache'];
        //}

        if ($this->isAction) {
            do {
                //if (!$this->createDataDirectory($submissionVars, $formVars)) {
                //  break;
                //}

                if (!$this->validateSettingsVars($submissionVars, $formVars)) {
                    break;
                }

                if (!$this->saveSiteSettings($submissionVars)) {
                    break;
                }

                system_message(elgg_echo('install:success:settings'));

                $this->continueToNextStep('settings');

            } while (FALSE);  // PHP doesn't support breaking out of if statements
        }

        $formVars = $this->makeFormSticky($formVars, $submissionVars);

        $this->render('settings', array('variables' => $formVars));
    }

    protected function admin($submissionVars) {
        $formVars = array(
            'displayname' => array(
                'type' => 'text',
                'value' => '',
                'required' => TRUE,
                ),
            'email' => array(
                'type' => 'email',
                'value' => '',
                'required' => TRUE,
                ),
            'username' => array(
                'type' => 'text',
                'value' => '',
                'required' => TRUE,
                ),
            'password1' => array(
                'type' => 'password',
                'value' => '',
                'required' => TRUE,
                'pattern' => '.{6,}',
                ),
            'password2' => array(
                'type' => 'password',
                'value' => '',
                'required' => TRUE,
                ),
        );

        if ($this->isAction) {
            do {
                if (!$this->validateAdminVars($submissionVars, $formVars)) {
                    break;
                }

                if (!$this->createAdminAccount($submissionVars, $this->autoLogin)) {
                    break;
                }

                system_message(elgg_echo('install:success:admin'));

                $this->continueToNextStep('admin');

            } while (FALSE);  // PHP doesn't support breaking out of if statements
        }

        // bit of a hack to get the password help to show right number of characters
        global $CONFIG;
        $lang = get_current_language();
        $CONFIG->translations[$lang]['install:admin:help:password1'] =
                sprintf($CONFIG->translations[$lang]['install:admin:help:password1'],
                $CONFIG->min_password_length);

        $formVars = $this->makeFormSticky($formVars, $submissionVars);

        $this->render('admin', array('variables' => $formVars));
    }

    protected function complete() {

        $params = array();
        if ($this->autoLogin) {
            $params['destination'] = 'admin';
        } else {
            $params['destination'] = 'index.php';
        }

        $this->render('complete', $params);
    }

    protected function getSteps() {
        return $this->steps;
    }

    protected function continueToNextStep($currentStep) {
        $this->isAction = FALSE;
        forward($this->getNextStepUrl($currentStep));
    }

    protected function getNextStep($currentStep) {
        $index = 1 + array_search($currentStep, $this->steps);
        if (isset($this->steps[$index])) {
            return $this->steps[$index];
        } else {
            return null;
        }
    }

    protected function getNextStepUrl($currentStep) {
        $nextStep = $this->getNextStep($currentStep);
        return elgg_get_site_url() . "install.php?step=$nextStep";
    }

    protected function setInstallStatus() {
        global $CONFIG;

        if (!is_readable("{$CONFIG->path}engine/settings.php")) {
            return;
        }

        $this->loadSettingsFile();

        $this->status['config'] = TRUE;

        // must be able to connect to database to jump install steps
        $dbSettingsPass = $this->checkDatabaseSettings(
                $CONFIG->dbuser,
                $CONFIG->dbpass,
                $CONFIG->dbname,
                $CONFIG->dbhost
                );
        if ($dbSettingsPass == FALSE) {
            return;
        }

        if (!include_once("{$CONFIG->path}engine/lib/database.php")) {
            throw new InstallationException(elgg_echo('InstallationException:MissingLibrary', array('database.php')));
        }

        // check that the config table has been created
        $query = "show tables";
        $result = get_data($query);
        if ($result) {
            foreach ($result as $table) {
                $table = (array) $table;
                if (in_array("{$CONFIG->dbprefix}config", $table)) {
                    $this->status['database'] = TRUE;
                }
            }
            if ($this->status['database'] == FALSE) {
                return;
            }
        } else {
            // no tables
            return;
        }

        // check that the config table has entries
        $query = "SELECT COUNT(*) AS total FROM {$CONFIG->dbprefix}config";
        $result = get_data($query);
        if ($result && $result[0]->total > 0) {
            $this->status['settings'] = TRUE;
        } else {
            return;
        }

        // check that the users entity table has an entry
        $query = "SELECT COUNT(*) AS total FROM {$CONFIG->dbprefix}users_entity";
        $result = get_data($query);
        if ($result && $result[0]->total > 0) {
            $this->status['admin'] = TRUE;
        } else {
            return;
        }
    }

    protected function checkInstallCompletion($step) {
        if ($step != 'complete') {
            if (!in_array(FALSE, $this->status)) {
                // install complete but someone is trying to view an install page
                forward();
            }
        }
    }

    protected function resumeInstall($step) {
        // only do a resume from the first step
        if ($step !== 'welcome') {
            return;
        }

        if ($this->status['database'] == FALSE) {
            return;
        }

        if ($this->status['settings'] == FALSE) {
            forward("install.php?step=settings");
        }

        if ($this->status['admin'] == FALSE) {
            forward("install.php?step=admin");
        }

        // everything appears to be set up
        forward("install.php?step=complete");
    }

    protected function bootstrapEngine() {
        global $CONFIG;

        $lib_dir = $CONFIG->path . 'engine/lib/';

        // bootstrapping with required files in a required order
        $required_files = array(
            'autoloader.php',
            'elgglib.php',
            'views.php',
            'access.php',
            'system_log.php',
            'configuration.php',
            'database.php',
            'sessions.php',
            'languages.php',
            'pageowner.php',
            'input.php',
            'cache.php',
            'output.php',
        );

        foreach ($required_files as $file) {
            $path = $lib_dir . $file;
            if (!include($path)) {
                echo "Could not load file '$path'. "
                    . 'Please check your Elgg installation for all required files.';
                exit;
            }
        }
    }

    protected function finishBootstraping($step) {

        $dbIndex = array_search('database', $this->getSteps());
        $settingsIndex = array_search('settings', $this->getSteps());
        $adminIndex = array_search('admin', $this->getSteps());
        $completeIndex = array_search('complete', $this->getSteps());
        $stepIndex = array_search($step, $this->getSteps());

        // To log in the user, we need to use the Elgg core session handling.
        // Otherwise, use default php session handling
        $useElggSession = ($stepIndex == $adminIndex && $this->isAction) ||
                $stepIndex == $completeIndex;
        if (!$useElggSession) {
            session_name('Elgg_install');
            session_start();
            elgg_unregister_event_handler('boot', 'system', 'session_init');
        }

        if ($stepIndex > $dbIndex) {
            // once the database has been created, load rest of engine
            global $CONFIG;
            $lib_dir = $CONFIG->path . 'engine/lib/';

            $this->loadSettingsFile();

            $lib_files = array(
                // these want to be loaded first apparently?
                'autoloader.php',
                'database.php',
                'actions.php',

                'admin.php',
                'annotations.php',
                'cron.php',
                'entities.php',
                'extender.php',
                'filestore.php',
                'group.php',
                'mb_wrapper.php',
                'memcache.php',
                'metadata.php',
                'metastrings.php',
                'navigation.php',
                'notification.php',
                'objects.php',
                'pagehandler.php',
                'pam.php',
                'plugins.php',
                'private_settings.php',
                'relationships.php',
                'river.php',
                'sites.php',
                'statistics.php',
                'tags.php',
                'user_settings.php',
                'users.php',
                'upgrade.php',
                'widgets.php',
                'deprecated-1.7.php',
                'deprecated-1.8.php',
                'deprecated-1.9.php',
            );

            foreach ($lib_files as $file) {
                $path = $lib_dir . $file;
                if (!include_once($path)) {
                    throw new InstallationException('InstallationException:MissingLibrary', array($file));
                }
            }

            _elgg_services()->db->setupConnections();
            register_translations(dirname(dirname(__FILE__)) . "/languages/");

            if ($stepIndex > $settingsIndex) {
                $CONFIG->site_guid = (int) datalist_get('default_site');
                $CONFIG->site_id = $CONFIG->site_guid;
                $CONFIG->site = get_entity($CONFIG->site_guid);
                $CONFIG->dataroot = datalist_get('dataroot');
                _elgg_session_boot();
            }

            elgg_trigger_event('init', 'system');
        }
    }

    protected function bootstrapConfig() {
        global $CONFIG;
        if (!isset($CONFIG)) {
            $CONFIG = new stdClass;
        }

        $CONFIG->wwwroot = $this->getBaseUrl();
        $CONFIG->url = $CONFIG->wwwroot;
        $CONFIG->path = dirname(dirname(__FILE__)) . '/';
        $CONFIG->viewpath = $CONFIG->path . 'views/';
        $CONFIG->pluginspath = $CONFIG->path . 'mod/';
        $CONFIG->context = array();
        $CONFIG->entity_types = array('group', 'object', 'site', 'user');
        // required by elgg_view_page()
        $CONFIG->sitename = '';
        $CONFIG->sitedescription = '';
    }

    private function isHttps() {
        return (!empty($_SERVER["HTTPS"]) && $_SERVER["HTTPS"] == "on") ||
            $_SERVER['SERVER_PORT'] == 443;
    }

    protected function getBaseUrl() {
        $protocol = $this->isHttps() ? 'https' : 'http';

        if (isset($_SERVER["SERVER_PORT"])) {
            $port = ':' . $_SERVER["SERVER_PORT"];
        } else {
            $port = '';
        }
        if ($port == ':80' || $port == ':443') {
            $port = '';
        }
        $uri = isset($_SERVER['REQUEST_URI']) ? $_SERVER['REQUEST_URI'] : '';
        $cutoff = strpos($uri, 'install.php');
        $uri = substr($uri, 0, $cutoff);
        $serverName = isset($_SERVER['SERVER_NAME']) ? $_SERVER['SERVER_NAME'] : '';

        return "$protocol://{$serverName}$port{$uri}";
    }

    protected function loadSettingsFile() {
        global $CONFIG;

        if (!include_once("{$CONFIG->path}engine/settings.php")) {
            throw new InstallationException(elgg_echo('InstallationException:CannotLoadSettings'));
        }
    }

    protected function getPostVariables() {
        $vars = array();
        foreach ($_POST as $k => $v) {
            $vars[$k] = $v;
        }
        return $vars;
    }

    protected function makeFormSticky($formVars, $submissionVars) {
        foreach ($submissionVars as $field => $value) {
            $formVars[$field]['value'] = $value;
        }
        return $formVars;
    }

    protected function checkEngineDir(&$report) {
        global $CONFIG;

        $writable = is_writable("{$CONFIG->path}engine");
        if (!$writable) {
            $report['settings'] = array(
                array(
                    'severity' => 'failure',
                    'message' => elgg_echo('install:check:enginedir'),
                )
            );
            return FALSE;
        }

        return TRUE;
    }

    protected function checkSettingsFile(&$report = array()) {
        global $CONFIG;

        if (!file_exists("{$CONFIG->path}engine/settings.php")) {
            return FALSE;
        }

        if (!is_readable("{$CONFIG->path}engine/settings.php")) {
            $report['settings'] = array(
                array(
                    'severity' => 'failure',
                    'message' => elgg_echo('install:check:readsettings'),
                )
            );
        }

        return TRUE;
    }

    protected function checkPHP(&$report) {
        $phpReport = array();

        $elgg_php_version = '5.2.0';
        if (version_compare(PHP_VERSION, $elgg_php_version, '<')) {
            $phpReport[] = array(
                'severity' => 'failure',
                'message' => elgg_echo('install:check:php:version', array($elgg_php_version, PHP_VERSION))
            );
        }

        $this->checkPhpExtensions($phpReport);

        $this->checkPhpDirectives($phpReport);

        if (count($phpReport) == 0) {
            $phpReport[] = array(
                'severity' => 'pass',
                'message' => elgg_echo('install:check:php:success')
            );
        }

        $report['php'] = $phpReport;
    }

    protected function checkPhpExtensions(&$phpReport) {
        $extensions = get_loaded_extensions();
        $requiredExtensions = array(
            'mysql',
            'json',
            'xml',
            'gd',
        );
        foreach ($requiredExtensions as $extension) {
            if (!in_array($extension, $extensions)) {
                $phpReport[] = array(
                    'severity' => 'failure',
                    'message' => elgg_echo('install:check:php:extension', array($extension))
                );
            }
        }

        $recommendedExtensions = array(
            'mbstring',
        );
        foreach ($recommendedExtensions as $extension) {
            if (!in_array($extension, $extensions)) {
                $phpReport[] = array(
                    'severity' => 'warning',
                    'message' => elgg_echo('install:check:php:extension:recommend', array($extension))
                );
            }
        }
    }

    protected function checkPhpDirectives(&$phpReport) {
        if (ini_get('open_basedir')) {
            $phpReport[] = array(
                'severity' => 'warning',
                'message' => elgg_echo("install:check:php:open_basedir")
            );
        }

        if (ini_get('safe_mode')) {
            $phpReport[] = array(
                'severity' => 'warning',
                'message' => elgg_echo("install:check:php:safe_mode")
            );
        }

        if (ini_get('arg_separator.output') !== '&') {
            $separator = htmlspecialchars(ini_get('arg_separator.output'));
            $msg = elgg_echo("install:check:php:arg_separator", array($separator));
            $phpReport[] = array(
                'severity' => 'failure',
                'message' => $msg,
            );
        }

        if (ini_get('register_globals')) {
            $phpReport[] = array(
                'severity' => 'failure',
                'message' => elgg_echo("install:check:php:register_globals")
            );
        }

        if (ini_get('session.auto_start')) {
            $phpReport[] = array(
                'severity' => 'failure',
                'message' => elgg_echo("install:check:php:session.auto_start")
            );
        }
    }

    protected function checkRewriteRules(&$report) {
        global $CONFIG;

        $tester = new ElggRewriteTester();
        $url = elgg_get_site_url() . "rewrite.php";
        $report['rewrite'] = array($tester->run($url, $CONFIG->path));
    }

    protected function processRewriteTest() {
        if (strpos($_SERVER['REQUEST_URI'], 'rewrite.php') !== FALSE) {
            echo 'success';
            exit;
        }
    }

    protected function countNumConditions($report, $condition) {
        $count = 0;
        foreach ($report as $category => $checks) {
            foreach ($checks as $check) {
                if ($check['severity'] === $condition) {
                    $count++;
                }
            }
        }

        return $count;
    }


    protected function validateDatabaseVars($submissionVars, $formVars) {

        foreach ($formVars as $field => $info) {
            if ($info['required'] == TRUE && !$submissionVars[$field]) {
                $name = elgg_echo("install:database:label:$field");
                register_error(elgg_echo('install:error:requiredfield', array($name)));
                return FALSE;
            }
        }

        // according to postgres documentation: SQL identifiers and key words must
        // begin with a letter (a-z, but also letters with diacritical marks and
        // non-Latin letters) or an underscore (_). Subsequent characters in an
        // identifier or key word can be letters, underscores, digits (0-9), or dollar signs ($).
        // Refs #4994
        if (!preg_match("/^[a-zA-Z_][\w]*$/", $submissionVars['dbprefix'])) {
            register_error(elgg_echo('install:error:database_prefix'));
            return FALSE;
        }

        return $this->checkDatabaseSettings(
                    $submissionVars['dbuser'],
                    $submissionVars['dbpassword'],
                    $submissionVars['dbname'],
                    $submissionVars['dbhost']
                );
    }

    protected function checkDatabaseSettings($user, $password, $dbname, $host) {
        $mysql_dblink = mysql_connect($host, $user, $password, true);
        if ($mysql_dblink == FALSE) {
            register_error(elgg_echo('install:error:databasesettings'));
            return FALSE;
        }

        $result = mysql_select_db($dbname, $mysql_dblink);

        // check MySQL version - must be 5.0 or >
        $required_version = 5.0;
        $version = mysql_get_server_info();
        $points = explode('.', $version);
        if ($points[0] < $required_version) {
            register_error(elgg_echo('install:error:oldmysql', array($version)));
            return FALSE;
        }

        mysql_close($mysql_dblink);

        if (!$result) {
            register_error(elgg_echo('install:error:nodatabase', array($dbname)));
        }

        return $result;
    }

    protected function createSettingsFile($params) {
        global $CONFIG;

        $templateFile = "{$CONFIG->path}engine/settings.example.php";
        $template = file_get_contents($templateFile);
        if (!$template) {
            register_error(elgg_echo('install:error:readsettingsphp'));
            return FALSE;
        }

        foreach ($params as $k => $v) {
            $template = str_replace("{{" . $k . "}}", $v, $template);
        }

        $settingsFilename = "{$CONFIG->path}engine/settings.php";
        $result = file_put_contents($settingsFilename, $template);
        if (!$result) {
            register_error(elgg_echo('install:error:writesettingphp'));
            return FALSE;
        }

        return TRUE;
    }

    protected function connectToDatabase() {
        global $CONFIG;

        if (!include_once("{$CONFIG->path}engine/settings.php")) {
            register_error('Elgg could not load the settings file. It does not exist or there is a file permissions issue.');
            return FALSE;
        }

        if (!include_once("{$CONFIG->path}engine/lib/database.php")) {
            register_error('Could not load database.php');
            return FALSE;
        }

        try  {
            _elgg_services()->db->setupConnections();
        } catch (DatabaseException $e) {
            register_error($e->getMessage());
            return FALSE;
        }

        return TRUE;
    }

    protected function installDatabase() {
        global $CONFIG;

        try {
            run_sql_script("{$CONFIG->path}engine/schema/mysql.sql");
        } catch (Exception $e) {
            $msg = $e->getMessage();
            if (strpos($msg, 'already exists')) {
                $msg = elgg_echo('install:error:tables_exist');
            }
            register_error($msg);
            return FALSE;
        }

        return TRUE;
    }

    protected function createDataDirectory(&$submissionVars, $formVars) {
        // did the user have option of Elgg creating the data directory
        if ($formVars['dataroot']['type'] != 'combo') {
            return TRUE;
        }

        // did the user select the option
        if ($submissionVars['dataroot'] != 'dataroot-checkbox') {
            return TRUE;
        }

        $dir = sanitise_filepath($submissionVars['path']) . 'data';
        if (file_exists($dir) || mkdir($dir, 0700)) {
            $submissionVars['dataroot'] = $dir;
            if (!file_exists("$dir/.htaccess")) {
                $htaccess = "Order Deny,Allow\nDeny from All\n";
                if (!file_put_contents("$dir/.htaccess", $htaccess)) {
                    return FALSE;
                }
            }
            return TRUE;
        }

        return FALSE;
    }

    protected function validateSettingsVars($submissionVars, $formVars) {
        global $CONFIG;

        foreach ($formVars as $field => $info) {
            $submissionVars[$field] = trim($submissionVars[$field]);
            if ($info['required'] == TRUE && $submissionVars[$field] === '') {
                $name = elgg_echo("install:settings:label:$field");
                register_error(elgg_echo('install:error:requiredfield', array($name)));
                return FALSE;
            }
        }

        // check that data root is absolute path
        if (stripos(PHP_OS, 'win') === 0) {
            if (strpos($submissionVars['dataroot'], ':') !== 1) {
                $msg = elgg_echo('install:error:relative_path', array($submissionVars['dataroot']));
                register_error($msg);
                return FALSE;
            }
        } else {
            if (strpos($submissionVars['dataroot'], '/') !== 0) {
                $msg = elgg_echo('install:error:relative_path', array($submissionVars['dataroot']));
                register_error($msg);
                return FALSE;
            }
        }

        // check that data root exists
        if (!file_exists($submissionVars['dataroot'])) {
            $msg = elgg_echo('install:error:datadirectoryexists', array($submissionVars['dataroot']));
            register_error($msg);
            return FALSE;
        }

        // check that data root is writable
        if (!is_writable($submissionVars['dataroot'])) {
            $msg = elgg_echo('install:error:writedatadirectory', array($submissionVars['dataroot']));
            register_error($msg);
            return FALSE;
        }

        if (!isset($CONFIG->data_dir_override) || !$CONFIG->data_dir_override) {
            // check that data root is not subdirectory of Elgg root
            if (stripos($submissionVars['dataroot'], $submissionVars['path']) === 0) {
                $msg = elgg_echo('install:error:locationdatadirectory', array($submissionVars['dataroot']));
                register_error($msg);
                return FALSE;
            }
        }

        // check that email address is email address
        if ($submissionVars['siteemail'] && !is_email_address($submissionVars['siteemail'])) {
            $msg = elgg_echo('install:error:emailaddress', array($submissionVars['siteemail']));
            register_error($msg);
            return FALSE;
        }

        // @todo check that url is a url
        // @note filter_var cannot be used because it doesn't work on international urls

        return TRUE;
    }

    protected function saveSiteSettings($submissionVars) {
        global $CONFIG;

        // ensure that file path, data path, and www root end in /
        $submissionVars['path'] = sanitise_filepath($submissionVars['path']);
        $submissionVars['dataroot'] = sanitise_filepath($submissionVars['dataroot']);
        $submissionVars['wwwroot'] = sanitise_filepath($submissionVars['wwwroot']);

        $site = new ElggSite();
        $site->name = strip_tags($submissionVars['sitename']);
        $site->url = $submissionVars['wwwroot'];
        $site->access_id = ACCESS_PUBLIC;
        $site->email = $submissionVars['siteemail'];
        $guid = $site->save();

        if (!$guid) {
            register_error(elgg_echo('install:error:createsite'));
            return FALSE;
        }

        // bootstrap site info
        $CONFIG->site_guid = $guid;
        $CONFIG->site_id = $guid;
        $CONFIG->site = $site;

        datalist_set('installed', time());
        datalist_set('path', $submissionVars['path']);
        datalist_set('dataroot', $submissionVars['dataroot']);
        datalist_set('default_site', $site->getGUID());
        datalist_set('version', elgg_get_version());
        datalist_set('simplecache_enabled', 1);
        datalist_set('system_cache_enabled', 1);
        datalist_set('simplecache_lastupdate', time());

        // new installations have run all the upgrades
        $upgrades = elgg_get_upgrade_files($submissionVars['path'] . 'engine/lib/upgrades/');
        datalist_set('processed_upgrades', serialize($upgrades));

        set_config('view', 'default', $site->getGUID());
        set_config('language', 'en', $site->getGUID());
        set_config('default_access', $submissionVars['siteaccess'], $site->getGUID());
        set_config('allow_registration', TRUE, $site->getGUID());
        set_config('walled_garden', FALSE, $site->getGUID());
        set_config('allow_user_default_access', '', $site->getGUID());

        $this->setSubtypeClasses();

        $this->enablePlugins();

        return TRUE;
    }

    protected function setSubtypeClasses() {
        add_subtype("object", "plugin", "ElggPlugin");
        add_subtype("object", "file", "ElggFile");
        add_subtype("object", "widget", "ElggWidget");
        add_subtype("object", "comment", "ElggComment");
        add_subtype("object", "elgg_upgrade", 'ElggUpgrade');
    }

    protected function enablePlugins() {
        _elgg_generate_plugin_entities();
        $plugins = elgg_get_plugins('any');
        foreach ($plugins as $plugin) {
            if ($plugin->getManifest()) {
                if ($plugin->getManifest()->getActivateOnInstall()) {
                    $plugin->activate();
                }
                if (in_array('theme', $plugin->getManifest()->getCategories())) {
                    $plugin->setPriority('last');
                }
            }
        }
    }

    protected function validateAdminVars($submissionVars, $formVars) {

        foreach ($formVars as $field => $info) {
            if ($info['required'] == TRUE && !$submissionVars[$field]) {
                $name = elgg_echo("install:admin:label:$field");
                register_error(elgg_echo('install:error:requiredfield', array($name)));
                return FALSE;
            }
        }

        if ($submissionVars['password1'] !== $submissionVars['password2']) {
            register_error(elgg_echo('install:admin:password:mismatch'));
            return FALSE;
        }

        if (trim($submissionVars['password1']) == "") {
            register_error(elgg_echo('install:admin:password:empty'));
            return FALSE;
        }

        $minLength = get_config('min_password_length');
        if (strlen($submissionVars['password1']) < $minLength) {
            register_error(elgg_echo('install:admin:password:tooshort'));
            return FALSE;
        }

        // check that email address is email address
        if ($submissionVars['email'] && !is_email_address($submissionVars['email'])) {
            $msg = elgg_echo('install:error:emailaddress', array($submissionVars['email']));
            register_error($msg);
            return FALSE;
        }

        return TRUE;
    }

    protected function createAdminAccount($submissionVars, $login = FALSE) {
        try {
            $guid = register_user(
                    $submissionVars['username'],
                    $submissionVars['password1'],
                    $submissionVars['displayname'],
                    $submissionVars['email']
                    );
        } catch (Exception $e) {
            register_error($e->getMessage());
            return false;
        }

        if (!$guid) {
            register_error(elgg_echo('install:admin:cannot_create'));
            return false;
        }

        $user = get_entity($guid);
        if (!$user instanceof ElggUser) {
            register_error(elgg_echo('install:error:loadadmin'));
            return false;
        }

        elgg_set_ignore_access(TRUE);
        if ($user->makeAdmin() == FALSE) {
            register_error(elgg_echo('install:error:adminaccess'));
        } else {
            datalist_set('admin_registered', 1);
        }
        elgg_set_ignore_access(false);

        // add validation data to satisfy user validation plugins
        create_metadata($guid, 'validated', TRUE, '', 0, ACCESS_PUBLIC);
        create_metadata($guid, 'validated_method', 'admin_user', '', 0, ACCESS_PUBLIC);

        if ($login) {
            $handler = new Elgg_Http_DatabaseSessionHandler(_elgg_services()->db);
            $storage = new Elgg_Http_NativeSessionStorage(array(), $handler);
            $session = new ElggSession($storage);
            $session->setName('Elgg');
            _elgg_services()->setValue('session', $session);
            if (login($user) == FALSE) {
                register_error(elgg_echo('install:error:adminlogin'));
            }
        }

        return TRUE;
    }
}