MaintenanceMode.module

<?php

class MaintenanceMode extends WireData implements Module, ConfigurableModule
{

    /**
     * Basic information about module
     */
    public static function getModuleInfo()
    {
        return array(
            'title' => 'Maintenance Mode',
            'summary' => 'Allows you to put your site into maintenance mode so that users who are not logged in are taken to the login screen and a message is displayed accordingly.',
            'href' => 'https://processwire.com/talk/topic/382-module-maintenance-mode/',
            'version' => 111,
            'permanent' => false,
            'autoload' => true,
            'singular' => true,
        );
    }

    /**
     * Default configuration for module
     *
     * This is based on Ryan's examples [used also in @apeisa's AdminBar, for instance]
     */
    static public function getDefaultData()
    {
        return array(
            'inMaintenance' => 0,
            'showPage' => 0,
            'showURL' => '',
            'bypassRoles' => '',
            'allowPages' => 0,
            'showFrontendNotice' => 1
        );
    }

    /**
     * Populate the default config data
     *
     */
    public function __construct()
    {
        foreach (self::getDefaultData() as $key => $value) {
            $this->$key = $value;
        }
    }

    /**
     * Initialize the module and setup hooks
     */
    public function init()
    {
        // hook before the page has been loaded to see if we're in maintenance mode and redirect if neccessary
        $this->addHookBefore('Page::render', $this, 'maintenanceCheck');
        $this->addHookAfter('Page::render', $this, 'maintenanceMessage');
    }

    /**
     * Ready hook to show admin notices
     */
    public function ready()
    {
        $user = $this->fuel('user');
        $page = $this->fuel('page');

        if ($user->isLoggedin() && $user->isSuperuser() && $page->template == 'admin' && !$this->config->ajax && !$this->input->requestMethod('POST')) {
            // Show persistent admin notice for maintenance mode
            if ($this->inMaintenance) {
                // Remove any leftover maintenance warnings from session to prevent duplicates
                foreach ($this->wire('notices') as $notice) {
                    if ($notice instanceof NoticeWarning && $notice->class === $this->className()) {
                        $this->wire('notices')->remove($notice);
                    }
                }
                $warning = __("Site is currently in maintenance mode");
                if ($this->modules->isInstalled('ProCache')) {
                    $procache = $this->modules->get('ProCache');
                    if ($procache && $procache->cacheOn) {
                        $warning .= '. ' . __("**Warning:** ProCache is enabled - cached pages may still be served to visitors during maintenance mode");
                    }
                }
                $this->warning($warning, Notice::allowMarkdown);
            }
        }
    }

    static public function getModuleConfigInputfields(array $data)
    {

        // this is a container for fields, basically like a fieldset
        $fields = new InputfieldWrapper();

        // since this is a static function, we can't use $this->modules, so get them from the global wire() function
        $modules = wire('modules');

        // Populate $data with the default config, because if they've never configured this module before,
        // the $data provided to this function will be empty. Or, if you add new config items in a new version,
        // $data won't have it until they configure it. Best bet is to merge defaults with custom, where
        // custom overwrites the defaults (array_merge).

        $data = array_merge(self::getDefaultData(), $data);

        // Populate the $fieldsModel with data for each checkbox
        $fieldsModel = array(
            'inMaintenance' => array(
                'label' => "Put site into maintenance mode?",
                'desc' => "Will redirect any visitors who are not logged in to your site to the login page with an appropriate message.",
                'type' => "_createCheckbox"),
            'bypassRoles' => array(
                'label' => "Allow specific roles to bypass maintenance mode",
                'desc' => "Optionally allow certain user roles eg. site editors/staff to see the side whilst in maintenance mode (superuser will always be allowed regardless of this setting)",
                'type' => "_createInputfieldASMSelect"),
            'showPage' => array(
                'label' => "Redirect to another page instead of the login page?",
                'desc' => "Alternatively shows a specific page instead of the login page - for added security.",
                'type' => "_createInputfieldPageListSelect"),
            'showURL' => array(
                'label' => "Redirect to another URL?",
                'desc' => "Allows you to send visitors who are not logged in to another URL including other sites.",
                'type' => "_createInputfieldURL"),
            'allowPages' => array(
                'label' => "Allowed Pages",
                'desc' => "These pages will always be accessible in maintenance mode",
                'type' => "_createInputfieldPageListSelectMultiple"),
            'showFrontendNotice' => array(
                'label' => "Show frontend maintenance notice?",
                'desc' => "Display a maintenance mode notice on the frontend for logged-in superusers",
                'type' => "_createCheckbox")
        );
        // Now use $data and $fieldsModel loop to create all checkboxes
        foreach ($fieldsModel as $f => $fM) {
            $fields->add(
                call_user_func(array(static::class, $fM['type']), $f, $fM['label'], $data[$f], $fM['desc'])
            );
        }
        return $fields;
    }

    /**
     * Checks if we're in maintenance mode and performs any neccessary redirects
     *
     * @param HookEvent $event
     */
    public function maintenanceCheck(HookEvent $event)
    {
        $page = $event->object;
        $user = $this->fuel('user');
        // If we're in maintenance mode
        if ($this->inMaintenance) {
            // Check to make sure we're not a superuser and our role isn't in the list of allowed roles to access the site in maintenance mode
            if (!$user->isSuperuser() && !array_intersect(explode('|', $user->roles), $this->bypassRoles)) {
                $this->message("This site is currently in maintenance mode. If you are a site administrator, you may log in below and view the site as normal.");

                // Redirect only if current page is not in array of allowed pages
                if (!in_array($page->id, $this->allowPages)) {

                    // If we have a different URL to redirect to then do a temp. redirect to that URL...
                    if ($this->showURL && ($page->name != 'login')) {
                        $this->session->redirect($this->showURL, false);

                        // If we have a specific page to redirect to then do it
                    } elseif ($this->showPage && ($page->id != $this->showPage) && ($page->name != 'login')) {
                        $this->session->redirect($this->fuel('pages')->get($this->showPage)->url, false);

                        // Else redirect to the login page
                    } elseif (!$this->showPage && $page->name != 'login') {
                        $this->session->redirect($this->config->urls->admin, false);
                    }

                }
            }
            // Else if we're not in maintenance mode and we're not an administrator, make sure the maintenance page redirects to the homepage
        } elseif (!$this->inMaintenance && $this->showPage && ($page->id == $this->showPage) && !$user->isSuperuser()) {
            $this->session->redirect($this->config->urls->root, false);
        }
    }

    public function maintenanceMessage(HookEvent $event)
    {
        if ($this->inMaintenance && $this->showFrontendNotice) {
            $user = $this->fuel('user');
            if ($user->isLoggedin() && $user->isSuperuser()) {
                $page = $event->object;
                // Show notice on frontend if enabled
                if ($page->template != 'admin') {
                    $out = $event->return;
                    // Check to see if the edit link is visible (it is in the default template at least when viewing pages in the front-end). If so, move message to the right of it.
                    $indent = strpos($out, 'editpage') !== false ? '60px;' : '0';
                    $code = "<div style='font-family: Arial; font-size: 12px; padding: 5px 6px; line-height: 14px; margin-left: {$indent}; background-color: #87A71B; color: #fff; z-index:99999; position: fixed; text-align: center;'>Site is in maintenance mode</div>";
                    $out = preg_replace('/(<body[^>]*>)/i', '$1' . $code, $out);
                    $event->return = $out;
                }
            }
        }
    }

    /**
     * @param string $chName – name of the field this ties to
     * @param string $chTitle – title of the field
     * @param boolean $chChecked – is the checkbox checked? (default: true)
     * @param string $chDesc – description (KISS) (default: empty)
     * @return InputfieldCheckbox – created checkbox
     */
    private static function _createCheckbox($chName, $chTitle, $chChecked = true, $chDesc = '')
    {
        $field = wire('modules')->get("InputfieldCheckbox");
        $field->name = $chName;
        $field->label = $chTitle;
        $field->description = $chDesc;
        $field->value = 1;
        $field->attr('checked', $chChecked ? 'checked' : '');
        return $field;
    }

    /**
     * @param string $ipName – name of the field this ties to
     * @param string $ipTitle – title of the field
     * @param boolean $ipValue – the value of the field (default: empty, i.e. no page selected)
     * @param string $ipDesc – description (KISS) (default: empty)
     * @return InputfieldPageListSelect – created page list select
     */
    private static function _createInputfieldPageListSelect($ipName, $ipTitle, $ipValue = '', $ipDesc = '')
    {
        $field = wire('modules')->get("InputfieldPageListSelect");
        $field->name = $ipName;
        $field->label = $ipTitle;
        $field->required = false;
        $field->description = $ipDesc;
        $field->attr('value', $ipValue);
        $field->set('unselectLabel', 'Unselect');
        if ($ipValue == 0) $field->collapsed = Inputfield::collapsedYes;
        return $field;
    }

    private static function _createInputfieldURL($name, $title, $value = '', $desc = '')
    {
        $field = wire('modules')->get("InputfieldURL");
        $field->name = $name;
        $field->label = $title;
        $field->required = false;
        $field->attr('value', $value);
        $field->description = $desc;
        $field->notes = "Example: http://another.place.com/index.html";
        if (!(int)ini_get('allow_url_fopen')) $field->error("Your PHP doesn't have 'allow_url_fopen' enabled, so the redirect to external URL option won't work.");
        if ('' === $value) $field->collapsed = Inputfield::collapsedYes;
        return $field;
    }

    private static function _createInputfieldASMSelect($aName, $aTitle, $aValue, $aDesc = '', $aOptions = '', $aNotes = '', $aWidth = 100)
    {
        if (!isset($aValue) || !is_array($aValue)) $aValue = '';
        $modules = Wire::getFuel('modules');
        $field = $modules->get("InputfieldAsmSelect");
        $field->attr('name', $aName);
        foreach (wire('roles') as $role) {
            $field->addOption($role->id, $role->name);
        }
        $field->attr('value', $aValue);
        $field->label = $aTitle;
        $field->description = $aDesc;
        $field->columnWidth = $aWidth;
        if (empty($aValue)) $field->collapsed = Inputfield::collapsedYes;
        return $field;
    }


    private static function _createInputfieldPageListSelectMultiple($ipName, $ipTitle, $ipValue = '', $ipDesc = '')
    {
        $field = wire('modules')->get("InputfieldPageListSelectMultiple");
        $field->name = $ipName;
        $field->label = $ipTitle;
        $field->required = false;
        $field->description = $ipDesc;
        $field->attr('value', $ipValue);
        $field->set('unselectLabel', 'Unselect');
        if ($ipValue == 0) $field->collapsed = Inputfield::collapsedYes;
        return $field;
    }
}