silverstripe-framework/src/Core/CustomMethods.php

331 lines
11 KiB
PHP

<?php
namespace SilverStripe\Core;
use BadMethodCallException;
use InvalidArgumentException;
use SilverStripe\Dev\Deprecation;
/**
* Allows an object to declare a set of custom methods
*/
trait CustomMethods
{
/**
* Custom method sources
*
* @var array
*/
protected static $extra_methods = [];
/**
* Name of methods to invoke by defineMethods for this instance
*
* @var array
*/
protected $extra_method_registers = [];
/**
* Non-custom methods
*
* @var array
*/
protected static $built_in_methods = [];
/**
* Attempts to locate and call a method dynamically added to a class at runtime if a default cannot be located
*
* You can add extra methods to a class using {@link Extensions}, {@link Object::createMethod()} or
* {@link Object::addWrapperMethod()}
*
* @param string $method
* @param array $arguments
* @return mixed
* @throws BadMethodCallException
*/
public function __call($method, $arguments)
{
// If the method cache was cleared by an an Object::add_extension() / Object::remove_extension()
// call, then we should rebuild it.
$class = static::class;
$config = $this->getExtraMethodConfig($method);
if (empty($config)) {
throw new BadMethodCallException(
"Object->__call(): the method '$method' does not exist on '$class'"
);
}
switch (true) {
case isset($config['callback']): {
return $config['callback']($this, $arguments);
}
case isset($config['property']) : {
$property = $config['property'];
$index = $config['index'];
$obj = $index !== null ?
$this->{$property}[$index] :
$this->{$property};
if (!$obj) {
throw new BadMethodCallException(
"Object->__call(): {$class} cannot pass control to {$property}({$index})."
. ' Perhaps this object was mistakenly destroyed?'
);
}
// Call without setOwner
if (empty($config['callSetOwnerFirst'])) {
return $obj->$method(...$arguments);
}
/** @var Extension $obj */
try {
$obj->setOwner($this);
return $obj->$method(...$arguments);
} finally {
$obj->clearOwner();
}
}
case isset($config['wrap']): {
array_unshift($arguments, $config['method']);
$wrapped = $config['wrap'];
return $this->$wrapped(...$arguments);
}
case isset($config['function']): {
return $config['function']($this, $arguments);
}
default: {
throw new BadMethodCallException(
"Object->__call(): extra method $method is invalid on $class:"
. var_export($config, true)
);
}
}
}
/**
* Adds any methods from {@link Extension} instances attached to this object.
* All these methods can then be called directly on the instance (transparently
* mapped through {@link __call()}), or called explicitly through {@link extend()}.
*
* @uses addMethodsFrom()
*/
protected function defineMethods()
{
// Define from all registered callbacks
foreach ($this->extra_method_registers as $callback) {
call_user_func($callback);
}
}
/**
* Register an callback to invoke that defines extra methods
*
* @param string $name
* @param callable $callback
*/
protected function registerExtraMethodCallback($name, $callback)
{
if (!isset($this->extra_method_registers[$name])) {
$this->extra_method_registers[$name] = $callback;
}
}
// --------------------------------------------------------------------------------------------------------------
/**
* Return TRUE if a method exists on this object
*
* This should be used rather than PHP's inbuild method_exists() as it takes into account methods added via
* extensions
*
* @param string $method
* @return bool
*/
public function hasMethod($method)
{
return method_exists($this, $method) || $this->getExtraMethodConfig($method);
}
/**
* Get meta-data details on a named method
*
* @param string $method
* @return array List of custom method details, if defined for this method
*/
protected function getExtraMethodConfig($method)
{
// Lazy define methods
if (!isset(self::$extra_methods[static::class])) {
$this->defineMethods();
}
if (isset(self::$extra_methods[static::class][strtolower($method)])) {
return self::$extra_methods[static::class][strtolower($method)];
}
return null;
}
/**
* Return the names of all the methods available on this object
*
* @param bool $custom include methods added dynamically at runtime
* @return array
*/
public function allMethodNames($custom = false)
{
$class = static::class;
if (!isset(self::$built_in_methods[$class])) {
self::$built_in_methods[$class] = array_map('strtolower', get_class_methods($this));
}
if ($custom && isset(self::$extra_methods[$class])) {
return array_merge(self::$built_in_methods[$class], array_keys(self::$extra_methods[$class]));
} else {
return self::$built_in_methods[$class];
}
}
/**
* @param object $extension
* @return array
*/
protected function findMethodsFromExtension($extension)
{
if (method_exists($extension, 'allMethodNames')) {
if ($extension instanceof Extension) {
try {
$extension->setOwner($this);
$methods = $extension->allMethodNames(true);
} finally {
$extension->clearOwner();
}
} else {
$methods = $extension->allMethodNames(true);
}
} else {
$class = get_class($extension);
if (!isset(self::$built_in_methods[$class])) {
self::$built_in_methods[$class] = array_map('strtolower', get_class_methods($extension));
}
$methods = self::$built_in_methods[$class];
}
return $methods;
}
/**
* Add all the methods from an object property (which is an {@link Extension}) to this object.
*
* @param string $property the property name
* @param string|int $index an index to use if the property is an array
* @throws InvalidArgumentException
*/
protected function addMethodsFrom($property, $index = null)
{
$class = static::class;
$extension = ($index !== null) ? $this->{$property}[$index] : $this->$property;
if (!$extension) {
throw new InvalidArgumentException(
"Object->addMethodsFrom(): could not add methods from {$class}->{$property}[$index]"
);
}
$methods = $this->findMethodsFromExtension($extension);
if ($methods) {
if ($extension instanceof Extension) {
Deprecation::notice(
'5.0',
'Register custom methods from extensions with addCallbackMethod.'
. ' callSetOwnerFirst will be removed in 5.0'
);
}
$methodInfo = [
'property' => $property,
'index' => $index,
'callSetOwnerFirst' => $extension instanceof Extension,
];
$newMethods = array_fill_keys($methods, $methodInfo);
if (isset(self::$extra_methods[$class])) {
self::$extra_methods[$class] =
array_merge(self::$extra_methods[$class], $newMethods);
} else {
self::$extra_methods[$class] = $newMethods;
}
}
}
/**
* Add all the methods from an object property (which is an {@link Extension}) to this object.
*
* @param string $property the property name
* @param string|int $index an index to use if the property is an array
*/
protected function removeMethodsFrom($property, $index = null)
{
$extension = ($index !== null) ? $this->{$property}[$index] : $this->$property;
$class = static::class;
if (!$extension) {
throw new InvalidArgumentException(
"Object->removeMethodsFrom(): could not remove methods from {$class}->{$property}[$index]"
);
}
$methods = $this->findMethodsFromExtension($extension);
if ($methods) {
foreach ($methods as $method) {
if (!isset(self::$extra_methods[$class][$method])) {
continue;
}
$methodInfo = self::$extra_methods[$class][$method];
// always check for property, AND
// check for index only if provided
if ((isset($methodInfo['property']) && $methodInfo['property'] === $property) &&
(!$index || ($index && isset($methodInfo['index']) && $methodInfo['index'] === $index))) {
unset(self::$extra_methods[$class][$method]);
}
}
if (empty(self::$extra_methods[$class])) {
unset(self::$extra_methods[$class]);
}
}
}
/**
* Add a wrapper method - a method which points to another method with a different name. For example, Thumbnail(x)
* can be wrapped to generateThumbnail(x)
*
* @param string $method the method name to wrap
* @param string $wrap the method name to wrap to
*/
protected function addWrapperMethod($method, $wrap)
{
self::$extra_methods[static::class][strtolower($method)] = [
'wrap' => $wrap,
'method' => $method
];
}
/**
* Add callback as a method.
*
* @param string $method Name of method
* @param callable $callback Callback to invoke.
* Note: $this is passed as first parameter to this callback and then $args as array
*/
protected function addCallbackMethod($method, $callback)
{
self::$extra_methods[static::class][strtolower($method)] = [
'callback' => $callback,
];
}
}