<?php
/**
* Module class file.
*
* @link http://www.yiiframework.com/
* @copyright Copyright © 2008-2012 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
namespace yii\base;
/**
* Module is the base class for module and application classes.
*
* Module mainly manages application components and sub-modules that belongs to a module.
*
* @property string $uniqueId An ID that uniquely identifies this module among all modules within
* the current application.
* @property string $basePath The root directory of the module. Defaults to the directory containing the module class.
* @property array $modules The configuration of the currently installed modules (module ID => configuration).
* @property array $components The application components (indexed by their IDs).
* @property array $import List of aliases to be imported. This property is write-only.
* @property array $aliases List of aliases to be defined. This property is write-only.
*
* @author Qiang Xue <qiang.xue@gmail.com>
* @since 2.0
*/
abstract class Module extends Component implements Initable
{
/**
* @var array custom module parameters (name => value).
*/
public $params = array();
/**
* @var array the IDs of the application components that should be preloaded when this module is created.
*/
public $preload = array();
/**
* @var string an ID that uniquely identifies this module among other modules which have the same [[parent]].
*/
public $id;
/**
* @var Module the parent module of this module. Null if this module does not have a parent.
*/
public $module;
private $_basePath;
private $_modules = array();
private $_components = array();
/**
* Constructor.
* @param string $id the ID of this module
* @param Module $parent the parent module (if any)
*/
public function __construct($id, $parent = null)
{
$this->id = $id;
$this->module = $parent;
}
/**
* Getter magic method.
* This method is overridden to support accessing application components
* like reading module properties.
* @param string $name application component or property name
* @return mixed the named property value
*/
public function __get($name)
{
if ($this->hasComponent($name)) {
return $this->getComponent($name);
} else {
return parent::__get($name);
}
}
/**
* Checks if a property value is null.
* This method overrides the parent implementation by checking
* if the named application component is loaded.
* @param string $name the property name or the event name
* @return boolean whether the property value is null
*/
public function __isset($name)
{
if ($this->hasComponent($name)) {
return $this->getComponent($name) !== null;
} else {
return parent::__isset($name);
}
}
/**
* Initializes the module.
* This method is called after the module is created and initialized with property values
* given in configuration. The default implement will create a path alias using the module [[id]]
* and then call [[preloadComponents()]] to load components that are declared in [[preload]].
*/
public function init()
{
\Yii::setAlias('@' . $this->id, $this->getBasePath());
$this->preloadComponents();
}
/**
* Returns an ID that uniquely identifies this module among all modules within the current application.
* @return string the unique ID of the module.
*/
public function getUniqueId()
{
if ($this->module && !$this->module instanceof Application) {
return $this->module->getUniqueId() . "/{$this->id}";
} else {
return $this->id;
}
}
/**
* Returns the root directory of the module.
* @return string the root directory of the module. Defaults to the directory containing the module class file.
*/
public function getBasePath()
{
if ($this->_basePath === null) {
$class = new \ReflectionClass($this);
$this->_basePath = dirname($class->getFileName());
}
return $this->_basePath;
}
/**
* Sets the root directory of the module.
* This method can only be invoked at the beginning of the constructor.
* @param string $path the root directory of the module.
* @throws Exception if the directory does not exist.
*/
public function setBasePath($path)
{
$p = \Yii::getAlias($path);
if ($p === false || !is_dir($p)) {
throw new Exception('Invalid base path: ' . $path);
} else {
$this->_basePath = realpath($p);
}
}
/**
* Imports the specified path aliases.
* This method is provided so that you can import a set of path aliases when configuring a module.
* The path aliases will be imported by calling [[\Yii::import()]].
* @param array $aliases list of path aliases to be imported
*/
public function setImport($aliases)
{
foreach ($aliases as $alias) {
\Yii::import($alias);
}
}
/**
* Defines path aliases.
* This method calls [[\Yii::setAlias()]] to register the path aliases.
* This method is provided so that you can define path aliases when configuring a module.
* @param array $aliases list of path aliases to be defined. The array keys are alias names
* (must start with '@') and the array values are the corresponding paths or aliases.
* For example,
*
* ~~~
* array(
* '@models' => '@app/models', // an existing alias
* '@backend' => __DIR__ . '/../backend', // a directory
* )
* ~~~
*/
public function setAliases($aliases)
{
foreach ($aliases as $name => $alias) {
\Yii::setAlias($name, $alias);
}
}
/**
* Checks whether the named module exists.
* @param string $id module ID
* @return boolean whether the named module exists. Both loaded and unloaded modules
* are considered.
*/
public function hasModule($id)
{
return isset($this->_modules[$id]);
}
/**
* Retrieves the named module.
* @param string $id module ID (case-sensitive)
* @param boolean $load whether to load the module if it is not yet loaded.
* @return Module|null the module instance, null if the module
* does not exist.
* @see hasModule()
*/
public function getModule($id, $load = true)
{
if (isset($this->_modules[$id])) {
if ($this->_modules[$id] instanceof Module) {
return $this->_modules[$id];
} elseif ($load) {
\Yii::trace("Loading \"$id\" module", __CLASS__);
return $this->_modules[$id] = \Yii::createObject($this->_modules[$id], $id, $this);
}
}
return null;
}
/**
* Adds a sub-module to this module.
* @param string $id module ID
* @param Module|array|null $module the sub-module to be added to this module. This can
* be one of the followings:
*
* - a [[Module]] object
* - a configuration array: when [[getModule()]] is called initially, the array
* will be used to instantiate the sub-module
* - null: the named sub-module will be removed from this module
*/
public function setModule($id, $module)
{
if ($module === null) {
unset($this->_modules[$id]);
} else {
$this->_modules[$id] = $module;
}
}
/**
* Returns the sub-modules in this module.
* @param boolean $loadedOnly whether to return the loaded sub-modules only. If this is set false,
* then all sub-modules registered in this module will be returned, whether they are loaded or not.
* Loaded modules will be returned as objects, while unloaded modules as configuration arrays.
* @return array the modules (indexed by their IDs)
*/
public function getModules($loadedOnly = false)
{
if ($loadedOnly) {
$modules = array();
foreach ($this->_modules as $module) {
if ($module instanceof Module) {
$modules[] = $module;
}
}
return $modules;
} else {
return $this->_modules;
}
}
/**
* Registers sub-modules in the current module.
*
* Each sub-module should be specified as a name-value pair, where
* name refers to the ID of the module and value the module or a configuration
* array that can be used to create the module. In the latter case, [[\Yii::createObject()]]
* will be used to create the module.
*
* If a new sub-module has the same ID as an existing one, the existing one will be overwritten silently.
*
* The following is an example for registering two sub-modules:
*
* ~~~
* array(
* 'comment' => array(
* 'class' => 'app\modules\CommentModule',
* 'connectionID' => 'db',
* ),
* 'booking' => array(
* 'class' => 'app\modules\BookingModule',
* ),
* )
* ~~~
*
* @param array $modules modules (id => module configuration or instances)
*/
public function setModules($modules)
{
foreach ($modules as $id => $module) {
$this->_modules[$id] = $module;
}
}
/**
* Checks whether the named component exists.
* @param string $id application component ID
* @return boolean whether the named application component exists. Both loaded and unloaded components
* are considered.
*/
public function hasComponent($id)
{
return isset($this->_components[$id]);
}
/**
* Retrieves the named application component.
* @param string $id application component ID (case-sensitive)
* @param boolean $load whether to load the component if it is not yet loaded.
* @return ApplicationComponent|null the application component instance, null if the application component
* does not exist.
* @see hasComponent()
*/
public function getComponent($id, $load = true)
{
if (isset($this->_components[$id])) {
if ($this->_components[$id] instanceof ApplicationComponent) {
return $this->_components[$id];
} elseif ($load) {
\Yii::trace("Loading \"$id\" application component", __CLASS__);
return $this->_components[$id] = \Yii::createObject($this->_components[$id]);
}
}
return null;
}
/**
* Registers an application component in this module.
* @param string $id component ID
* @param ApplicationComponent|array|null $component the component to be added to the module. This can
* be one of the followings:
*
* - an [[ApplicationComponent]] object
* - a configuration array: when [[getComponent()]] is called initially for this component, the array
* will be used to instantiate the component
* - null: the named component will be removed from the module
*/
public function setComponent($id, $component)
{
if ($component === null) {
unset($this->_components[$id]);
} else {
$this->_components[$id] = $component;
}
}
/**
* Returns the application components.
* @param boolean $loadedOnly whether to return the loaded components only. If this is set false,
* then all components specified in the configuration will be returned, whether they are loaded or not.
* Loaded components will be returned as objects, while unloaded components as configuration arrays.
* @return array the application components (indexed by their IDs)
*/
public function getComponents($loadedOnly = false)
{
if ($loadedOnly) {
$components = array();
foreach ($this->_components as $component) {
if ($component instanceof ApplicationComponent) {
$components[] = $component;
}
}
return $components;
} else {
return $this->_components;
}
}
/**
* Registers a set of application components in this module.
*
* Each application component should be specified as a name-value pair, where
* name refers to the ID of the component and value the component or a configuration
* array that can be used to create the component. In the latter case, [[\Yii::createObject()]]
* will be used to create the component.
*
* If a new component has the same ID as an existing one, the existing one will be overwritten silently.
*
* The following is an example for setting two components:
*
* ~~~
* array(
* 'db' => array(
* 'class' => 'yii\db\dao\Connection',
* 'dsn' => 'sqlite:path/to/file.db',
* ),
* 'cache' => array(
* 'class' => 'yii\caching\DbCache',
* 'connectionID' => 'db',
* ),
* )
* ~~~
*
* @param array $components application components (id => component configuration or instance)
*/
public function setComponents($components)
{
foreach ($components as $id => $component) {
$this->_components[$id] = $component;
}
}
/**
* Loads application components that are declared in [[preload]].
*/
public function preloadComponents()
{
foreach ($this->preload as $id) {
$this->getComponent($id);
}
}
}