Introducing aliases for Beans

src/bitExpert/Disco/AnnotationBeanFactory.php

@@ -8,12 +8,12 @@
  * For the full copyright and license information, please view the LICENSE
  * file that was distributed with this source code.
  */
-declare(strict_types=1);
+declare(strict_types = 1);
 
 namespace bitExpert\Disco;
 
+use bitExpert\Disco\Proxy\Configuration\AliasContainerInterface;
 use bitExpert\Disco\Proxy\Configuration\ConfigurationFactory;
-use Exception;
 
 /**
  * {@link \bitExpert\Disco\BeanFactory} implementation.
@@ -35,7 +35,7 @@ class AnnotationBeanFactory implements BeanFactory
      */
     protected $config;
     /**
-     * @var object
+     * @var AliasContainerInterface
      */
     protected $beanStore;
 
@@ -64,19 +64,22 @@ public function get($id)
     {
         $instance = null;
 
-        $id = $this->normalizeBeanId($id);
-        if ($this->beanIdExists($id)) {
-            try {
-                $instance = call_user_func([$this->beanStore, $id]);
-            } catch (\Throwable $e) {
-                $message = sprintf(
-                    'Exception occured while instanciating "%s": %s',
-                    $id,
-                    $e->getMessage()
-                );
-
-                throw new BeanException($message, 0, $e);
+        try {
+            if (is_callable([$this->beanStore, $id])) {
+                $instance = $this->beanStore->$id();
             }
+
+            if ($this->beanStore->hasAlias($id)) {
+                $instance = $this->beanStore->getAlias($id);
+            }
+        } catch (\Throwable $e) {
+            $message = sprintf(
+                'Exception occured while instanciating "%s": %s',
+                $id,
+                $e->getMessage()
+            );
+
+            throw new BeanException($message, 0, $e);
         }
 
         if (null === $instance) {
@@ -91,8 +94,7 @@ public function get($id)
      */
     public function has($id)
     {
-        $id = $this->normalizeBeanId($id);
-        return $this->beanIdExists($id);
+        return is_callable([$this->beanStore, $id]) || $this->beanStore->hasAlias($id);
     }
 
     /**
@@ -124,40 +126,4 @@ protected function initBeanStore($configClassName, array $parameters, BeanFactor
         $configFactory = new ConfigurationFactory($config);
         return $configFactory->createInstance($configClassName, $parameters);
     }
-
-    /**
-     * Helper method to "normalize" bean identifiers. Since the bean identifier is basically a method name
-     * of the config class we can only support a subset of characters, namely alphabetic characters, digits
-     * and underscore.
-     *
-     * @param string $id
-     * @return string
-     */
-    protected function normalizeBeanId($id)
-    {
-        // filter out all invalid characters
-        $id = preg_replace('#[^a-zA-Z0-9_]#', '', $id);
-        // prepend underscore when first character is neither an alphabetic character nor a underscore
-        if (!preg_match('#^[a-zA-Z_]#', $id)) {
-            $id = '_' . $id;
-        }
-
-        return $id;
-    }
-
-    /**
-     * Returns true if the container can return an entry for the given identifier.
-     * Returns false otherwise. Expects $id to be normalized!
-     *
-     * @param string $id Identifier of the entry to look for.
-     * @return boolean
-     */
-    protected function beanIdExists($id)
-    {
-        if (empty($id) or !is_string($id)) {
-            return false;
-        }
-
-        return is_callable([$this->beanStore, $id]);
-    }
 }

src/bitExpert/Disco/Annotations/Bean.php

@@ -12,6 +12,8 @@
 
 namespace bitExpert\Disco\Annotations;
 
+use Doctrine\Common\Annotations\Annotation\Attribute;
+use Doctrine\Common\Annotations\Annotation\Attributes;
 use Doctrine\Common\Annotations\AnnotationException;
 
 /**
@@ -21,6 +23,7 @@
  *   @Attribute("scope", type = "string"),
  *   @Attribute("singleton", type = "bool"),
  *   @Attribute("lazy", type = "bool"),
+ *   @Attribute("alias", type = "string"),
  * })
  */
 class Bean
@@ -52,6 +55,7 @@ public function __construct(array $attributes = [])
         $this->scope = self::SCOPE_REQUEST;
         $this->singleton = true;
         $this->lazy = false;
+        $this->alias = '';
 
         if (isset($attributes['value'])) {
             if (isset($attributes['value']['scope']) && (strtolower($attributes['value']['scope']) === 'session')) {
@@ -65,6 +69,10 @@ public function __construct(array $attributes = [])
             if (isset($attributes['value']['lazy'])) {
                 $this->lazy = $this->parseBooleanValue($attributes['value']['lazy']);
             }
+
+            if (isset($attributes['value']['alias'])) {
+                $this->alias = $attributes['value']['alias'];
+            }
         }
     }
 
@@ -108,6 +116,15 @@ public function isLazy() : bool
         return $this->lazy;
     }
 
+    /**
+     * Returns the alias for the bean instance. Returns an empty string when no alias was set.
+     * @return string
+     */
+    public function getAlias(): string
+    {
+        return $this->alias;
+    }
+
     /**
      * Helper function to cast a string value to a boolean representation.
      *

src/bitExpert/Disco/Proxy/Configuration/AliasContainerInterface.php

@@ -0,0 +1,42 @@
+<?php
+
+/*
+ * This file is part of the Disco package.
+ *
+ * (c) bitExpert AG
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+declare(strict_types=1);
+
+namespace bitExpert\Disco\Proxy\Configuration;
+
+use bitExpert\Disco\BeanException;
+use bitExpert\Disco\BeanNotFoundException;
+
+/**
+ * Interface similar to {@link \Interop\Container\ContainerInterface}. The interface is needed
+ * to be able to retrieve aliased beans from the generated configuration class.
+ */
+interface AliasContainerInterface
+{
+    /**
+     * Finds an entry of the container by the given alias and returns it.
+     *
+     * @param string $alias Alias of the entry to look for.
+     * @return mixed
+     * @throws BeanNotFoundException  No entry was found for this alias.
+     * @throws BeanException Error while retrieving the entry.
+     */
+    public function getAlias(string $alias);
+
+    /**
+     * Returns true if the container can return an entry for the given alias.
+     * Returns false otherwise.
+     *
+     * @param string $alias Identifier of the entry to look for
+     * @return boolean
+     */
+    public function hasAlias(string $alias) : bool;
+}

src/bitExpert/Disco/Proxy/Configuration/AliasesProperty.php

@@ -0,0 +1,33 @@
+<?php
+
+/*
+ * This file is part of the Disco package.
+ *
+ * (c) bitExpert AG
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+declare(strict_types=1);
+
+namespace bitExpert\Disco\Proxy\Configuration;
+
+use ProxyManager\Generator\Util\UniqueIdentifierGenerator;
+use Zend\Code\Generator\PropertyGenerator;
+
+/**
+ * Private property to store alias lookups for the bean instances.
+ */
+class AliasesProperty extends PropertyGenerator
+{
+    /**
+     * Creates a new {@link \bitExpert\Disco\Proxy\Configuration\AliasesProperty}.
+     */
+    public function __construct()
+    {
+        parent::__construct(UniqueIdentifierGenerator::getIdentifier('aliases'));
+
+        $this->setVisibility(self::VISIBILITY_PRIVATE);
+        $this->setDocBlock('@var array contains a list of aliases and their bean references');
+    }
+}

src/bitExpert/Disco/Proxy/Configuration/ConfigurationGenerator.php

@@ -18,7 +18,9 @@
 use bitExpert\Disco\Annotations\Parameters;
 use bitExpert\Disco\Proxy\Configuration\MethodGenerator\BeanMethod;
 use bitExpert\Disco\Proxy\Configuration\MethodGenerator\Constructor;
+use bitExpert\Disco\Proxy\Configuration\MethodGenerator\GetAlias;
 use bitExpert\Disco\Proxy\Configuration\MethodGenerator\GetParameter;
+use bitExpert\Disco\Proxy\Configuration\MethodGenerator\HasAlias;
 use bitExpert\Disco\Proxy\Configuration\MethodGenerator\MagicSleep;
 use Doctrine\Common\Annotations\AnnotationReader;
 use Doctrine\Common\Annotations\AnnotationRegistry;
@@ -78,6 +80,7 @@ public function generate(ReflectionClass $originalClass, ClassGenerator $classGe
         $sessionBeansProperty = new SessionBeansProperty();
         $postProcessorsProperty = new BeanPostProcessorsProperty();
         $parameterValuesProperty = new ParameterValuesProperty();
+        $aliasesProperty = new AliasesProperty();
         $getParameterMethod = new GetParameter($originalClass, $parameterValuesProperty);
 
         try {
@@ -96,12 +99,15 @@ public function generate(ReflectionClass $originalClass, ClassGenerator $classGe
         }
 
         $classGenerator->setExtendedClass($originalClass->getName());
+        $classGenerator->setImplementedInterfaces([AliasContainerInterface::class]);
         $classGenerator->addPropertyFromGenerator($forceLazyInitProperty);
         $classGenerator->addPropertyFromGenerator($sessionBeansProperty);
         $classGenerator->addPropertyFromGenerator($postProcessorsProperty);
         $classGenerator->addPropertyFromGenerator($parameterValuesProperty);
+        $classGenerator->addPropertyFromGenerator($aliasesProperty);
 
         $postProcessorMethods = [];
+        $aliases = [];
         $methods = $originalClass->getMethods(ReflectionMethod::IS_PUBLIC | ReflectionMethod::IS_PROTECTED);
         foreach ($methods as $method) {
             if (null !== $this->reader->getMethodAnnotation($method, BeanPostProcessor::class)) {
@@ -121,6 +127,11 @@ public function generate(ReflectionClass $originalClass, ClassGenerator $classGe
                 );
             }
 
+            // if alias is defined append it to the aliases list
+            if ($beanAnnotation->getAlias() !== '' && !isset($aliases[$beanAnnotation->getAlias()])) {
+                $aliases[$beanAnnotation->getAlias()] = $method->getName();
+            }
+
             /* @var \bitExpert\Disco\Annotations\Parameters $parametersAnnotation */
             $parametersAnnotation = $this->reader->getMethodAnnotation($method, Parameters::class);
             if (null === $parametersAnnotation) {
@@ -168,6 +179,8 @@ public function generate(ReflectionClass $originalClass, ClassGenerator $classGe
             $classGenerator->addMethodFromGenerator($proxyMethod);
         }
 
+        $aliasesProperty->setDefaultValue($aliases);
+
         $classGenerator->addMethodFromGenerator(
             new Constructor(
                 $originalClass,
@@ -183,5 +196,17 @@ public function generate(ReflectionClass $originalClass, ClassGenerator $classGe
                 $sessionBeansProperty
             )
         );
+        $classGenerator->addMethodFromGenerator(
+            new GetAlias(
+                $originalClass,
+                $aliasesProperty
+            )
+        );
+        $classGenerator->addMethodFromGenerator(
+            new HasAlias(
+                $originalClass,
+                $aliasesProperty
+            )
+        );
     }
 }

src/bitExpert/Disco/Proxy/Configuration/MethodGenerator/GetAlias.php

@@ -0,0 +1,51 @@
+<?php
+
+/*
+ * This file is part of the Disco package.
+ *
+ * (c) bitExpert AG
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+declare(strict_types = 1);
+
+namespace bitExpert\Disco\Proxy\Configuration\MethodGenerator;
+
+use bitExpert\Disco\BeanNotFoundException;
+use bitExpert\Disco\Proxy\Configuration\AliasesProperty;
+use ProxyManager\Generator\MethodGenerator;
+use ReflectionClass;
+use Zend\Code\Generator\ParameterGenerator;
+
+/**
+ * `getAlias` method for the generated config proxy class.
+ */
+class GetAlias extends MethodGenerator
+{
+    /**
+     * Creates a new {@link \bitExpert\Disco\Proxy\Configuration\MethodGenerator\GetAlias}.
+     *
+     * @param ReflectionClass $originalClass
+     * @param AliasesProperty $aliasesProperty
+     */
+    public function __construct(ReflectionClass $originalClass, AliasesProperty $aliasesProperty)
+    {
+        parent::__construct('getAlias');
+
+        $aliasParameter = new ParameterGenerator('alias');
+        $aliasParameter->setType('string');
+
+        $body = 'if ($this->hasAlias($'.$aliasParameter->getName().')) {' . PHP_EOL;
+        $body .= '    $methodname = $this->' . $aliasesProperty->getName() . '[$'.$aliasParameter->getName().'];' .
+            PHP_EOL;
+        $body .= '    return $this->$methodname();' . PHP_EOL;
+        $body .= '}' . PHP_EOL . PHP_EOL;
+        $body .= 'throw new '.BeanNotFoundException::class.'(sprintf(\'Alias "%s" is not defined!\', $'.
+            $aliasParameter->getName().'));' . PHP_EOL;
+
+        $this->setParameter($aliasParameter);
+        $this->setVisibility(self::VISIBILITY_PUBLIC);
+        $this->setBody($body);
+    }
+}