diff options
Diffstat (limited to 'program/include/rcube_plugin_api.php')
-rw-r--r-- | program/include/rcube_plugin_api.php | 312 |
1 files changed, 312 insertions, 0 deletions
diff --git a/program/include/rcube_plugin_api.php b/program/include/rcube_plugin_api.php new file mode 100644 index 000000000..4780f2e7e --- /dev/null +++ b/program/include/rcube_plugin_api.php @@ -0,0 +1,312 @@ +<?php + +/* + +-----------------------------------------------------------------------+ + | program/include/rcube_plugin_api.php | + | | + | This file is part of the RoundCube Webmail client | + | Copyright (C) 2008-2009, RoundCube Dev. - Switzerland | + | Licensed under the GNU GPL | + | | + | PURPOSE: | + | Plugins repository | + | | + +-----------------------------------------------------------------------+ + | Author: Thomas Bruederli <roundcube@gmail.com> | + +-----------------------------------------------------------------------+ + + $Id: $ + +*/ + +/** + * The plugin loader and global API + * + * @package Core + */ +class rcube_plugin_api +{ + static private $instance; + + public $dir; + public $url = 'plugins/'; + public $output; + + public $handlers = array(); + private $plugins = array(); + private $actions = array(); + private $actionmap = array(); + private $objectsmap = array(); + private $template_contents = array(); + + private $required_plugins = array('filesystem_attachments'); + + /** + * This implements the 'singleton' design pattern + * + * @return object rcube_plugin_api The one and only instance if this class + */ + static function get_instance() + { + if (!self::$instance) { + self::$instance = new rcube_plugin_api(); + } + + return self::$instance; + } + + + /** + * Private constructor + */ + private function __construct() + { + $rcmail = rcmail::get_instance(); + $this->dir = realpath($rcmail->config->get('plugins_dir')); + } + + + /** + * Load and init all enabled plugins + * + * This has to be done after rcmail::load_gui() or rcmail::init_json() + * was called because plugins need to have access to rcmail->output + */ + public function init() + { + $rcmail = rcmail::get_instance(); + $this->output = $rcmail->output; + + $plugins_dir = dir($this->dir); + $plugins_enabled = (array)$rcmail->config->get('plugins', array()); + + foreach ($plugins_enabled as $plugin_name) { + $fn = $plugins_dir->path . DIRECTORY_SEPARATOR . $plugin_name . DIRECTORY_SEPARATOR . $plugin_name . '.php'; + + if (file_exists($fn)) { + include($fn); + + // instantiate class if exists + if (class_exists($plugin_name, false)) { + $plugin = new $plugin_name($this); + // check inheritance and task specification + if (is_subclass_of($plugin, 'rcube_plugin') && (!$plugin->task || $plugin->task == $rcmail->task)) { + $plugin->init(); + $this->plugins[] = $plugin; + } + } + else { + raise_error(array('code' => 520, 'type' => 'php', 'message' => "No plugin class $plugin_name found in $fn"), true, false); + } + } + else { + raise_error(array('code' => 520, 'type' => 'php', 'message' => "Failed to load plugin file $fn"), true, false); + } + } + + // check existance of all required core plugins + foreach ($this->required_plugins as $plugin_name) { + $loaded = false; + foreach ($this->plugins as $plugin) { + if ($plugin instanceof $plugin_name) { + $loaded = true; + break; + } + } + + // load required core plugin if no derivate was found + if (!$loaded) { + $fn = $plugins_dir->path . DIRECTORY_SEPARATOR . $plugin_name . DIRECTORY_SEPARATOR . $plugin_name . '.php'; + if (file_exists($fn)) { + include($fn); + + if (class_exists($plugin_name, false)) { + $plugin = new $plugin_name($this); + // check inheritance + if (is_subclass_of($plugin, 'rcube_plugin')) { + $plugin->init(); + $this->plugins[] = $plugin; + $loaded = true; + } + } + } + } + + // trigger fatal error if still not loaded + if (!$loaded) { + raise_error(array('code' => 520, 'type' => 'php', 'message' => "Requried plugin $plugin_name was not loaded"), true, true); + } + } + + // register an internal hook + $this->register_hook('template_container', array($this, 'template_container_hook')); + + // maybe also register a shudown function which triggers shutdown functions of all plugin objects + + + // call imap_init right now + // (should actually be done in rcmail::imap_init() but plugins are not initialized then) + if ($rcmail->imap) { + $hook = $this->exec_hook('imap_init', array('fetch_headers' => $rcmail->imap->fetch_add_headers)); + if ($hook['fetch_headers']) + $rcmail->imap->fetch_add_headers = $hook['fetch_headers']; + } + } + + + /** + * Allows a plugin object to register a callback for a certain hook + * + * @param string Hook name + * @param mixed String with global function name or array($obj, 'methodname') + */ + public function register_hook($hook, $callback) + { + if (is_callable($callback)) + $this->handlers[$hook][] = $callback; + else + raise_error(array('code' => 521, 'type' => 'php', 'message' => "Invalid callback function for $hook"), true, false); + } + + + /** + * Triggers a plugin hook. + * This is called from the application and executes all registered handlers + * + * @param string Hook name + * @param array Named arguments (key->value pairs) + * @return array The (probably) altered hook arguments + */ + public function exec_hook($hook, $args = array()) + { + $args += array('abort' => false); + + foreach ((array)$this->handlers[$hook] as $callback) { + $ret = call_user_func($callback, $args); + if ($ret && is_array($ret)) + $args = $ret + $args; + + if ($args['abort']) + break; + } + + return $args; + } + + + /** + * Let a plugin register a handler for a specific request + * + * @param string Action name (_task=mail&_action=plugin.foo) + * @param string Plugin name that registers this action + * @param mixed Callback: string with global function name or array($obj, 'methodname') + */ + public function register_action($action, $owner, $callback) + { + // check action name + if (strpos($action, 'plugin.') !== 0) + $action = 'plugin.'.$action; + + // can register action only if it's not taken or registered by myself + if (!isset($this->actionmap[$action]) || $this->actionmap[$action] == $owner) { + $this->actions[$action] = $callback; + $this->actionmap[$action] = $owner; + } + else { + raise_error(array('code' => 523, 'type' => 'php', 'message' => "Cannot register action $action; already taken by another plugin"), true, false); + } + } + + + /** + * This method handles requests like _task=mail&_action=plugin.foo + * It executes the callback function that was registered with the given action. + * + * @param string Action name + */ + public function exec_action($action) + { + if (isset($this->actions[$action])) { + call_user_func($this->actions[$action]); + } + else { + raise_error(array('code' => 524, 'type' => 'php', 'message' => "No handler found for action $action"), true, true); + } + } + + + /** + * Register a handler function for template objects + * + * @param string Object name + * @param string Plugin name that registers this action + * @param mixed Callback: string with global function name or array($obj, 'methodname') + */ + public function register_handler($name, $owner, $callback) + { + // check name + if (strpos($name, 'plugin.') !== 0) + $name = 'plugin.'.$name; + + // can register handler only if it's not taken or registered by myself + if (!isset($this->objectsmap[$name]) || $this->objectsmap[$name] == $owner) { + $this->output->add_handler($name, $callback); + $this->objectsmap[$name] = $owner; + } + else { + raise_error(array('code' => 525, 'type' => 'php', 'message' => "Cannot register template handler $name; already taken by another plugin"), true, false); + } + } + + /** + * Include a plugin script file in the current HTML page + */ + public function include_script($fn) + { + if ($this->output->type == 'html') { + $src = $this->ressource_url($fn); + $this->output->add_header(html::tag('script', array('type' => "text/javascript", 'src' => $src))); + } + } + + /** + * Include a plugin stylesheet in the current HTML page + */ + public function include_stylesheet($fn) + { + if ($this->output->type == 'html') { + $src = $this->ressource_url($fn); + $this->output->add_header(html::tag('link', array('rel' => "stylesheet", 'type' => "text/css", 'href' => $src))); + } + } + + /** + * Save the given HTML content to be added to a template container + */ + public function add_content($html, $container) + { + $this->template_contents[$container] .= $html . "\n"; + } + + /** + * Callback for template_container hooks + */ + private function template_container_hook($attrib) + { + $container = $attrib['name']; + return array('content' => $this->template_contents[$container]); + } + + /** + * Make the given file name link into the plugins directory + */ + private function ressource_url($fn) + { + if ($fn[0] != '/' && !eregi('^https?://', $fn)) + return $this->url . $fn; + else + return $fn; + } + +} + |