feature #25288 [DI][FrameworkBundle] Add PSR-11 "ContainerBag" to acc…

…ess parameters as-a-service (nicolas-grekas, sroze)

This PR was merged into the 4.1-dev branch.

Discussion
----------

[DI][FrameworkBundle] Add PSR-11 "ContainerBag" to access parameters as-a-service

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #17160
| License       | MIT
| Doc PR        | -

There is one thing that prevents us from not injecting the container: access to the parameter bag.
This PR fixes this limitation by providing a PSR-11 `ContainerBagInterface` + related implementation, and wiring it as a service that ppl can then also autowire using the new interface as a type hint, or `ParameterBagInterface`.

Needed to complete e.g. #24738

Commits
-------

561cd7e Add tests on the ContainerBag
0e18d3e [DI][FrameworkBundle] Add PSR-11 "ContainerBag" to access parameters as-a-service

src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md

@@ -4,7 +4,8 @@ CHANGELOG
 4.1.0
 -----
 
- * allowed to pass an optional `LoggerInterface $logger` instance to the `Router`
+ * Allowed to pass an optional `LoggerInterface $logger` instance to the `Router`
+ * Added a new `parameter_bag` service with related autowiring aliases to acces parameters as-a-service
 
 4.0.0
 -----

src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php

@@ -35,6 +35,8 @@
 use Symfony\Component\DependencyInjection\Exception\InvalidArgumentException;
 use Symfony\Component\DependencyInjection\Exception\LogicException;
 use Symfony\Component\DependencyInjection\Loader\XmlFileLoader;
+use Symfony\Component\DependencyInjection\ParameterBag\ContainerBagInterface;
+use Symfony\Component\DependencyInjection\ParameterBag\ParameterBagInterface;
 use Symfony\Component\DependencyInjection\Reference;
 use Symfony\Component\DependencyInjection\ServiceSubscriberInterface;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
@@ -111,6 +113,12 @@ public function load(array $configs, ContainerBuilder $container)
         $loader->load('services.xml');
         $loader->load('fragment_renderer.xml');
 
+        if (!interface_exists(ContainerBagInterface::class)) {
+            $container->removeDefinition('parameter_bag');
+            $container->removeAlias(ContainerBagInterface::class);
+            $container->removeAlias(ParameterBagInterface::class);
+        }
+
         if (class_exists(Application::class)) {
             $loader->load('console.xml');
 

src/Symfony/Bundle/FrameworkBundle/Resources/config/services.xml

@@ -7,6 +7,12 @@
     <services>
         <defaults public="false" />
 
+        <service id="parameter_bag" class="Symfony\Component\DependencyInjection\ParameterBag\ContainerBag">
+            <argument type="service" id="service_container" />
+        </service>
+        <service id="Symfony\Component\DependencyInjection\ParameterBag\ContainerBagInterface" alias="parameter_bag" />
+        <service id="Symfony\Component\DependencyInjection\ParameterBag\ParameterBagInterface" alias="parameter_bag" />
+
         <service id="event_dispatcher" class="Symfony\Component\EventDispatcher\EventDispatcher" public="true">
             <tag name="container.hot_path" />
         </service>

src/Symfony/Component/DependencyInjection/CHANGELOG.md

@@ -5,6 +5,7 @@ CHANGELOG
 -----
 
  * added support for variadics in named arguments
+ * added PSR-11 `ContainerBagInterface` and its `ContainerBag` implementation to access parameters as-a-service
 
 4.0.0
 -----

src/Symfony/Component/DependencyInjection/Exception/ParameterNotFoundException.php

@@ -11,12 +11,14 @@
 
 namespace Symfony\Component\DependencyInjection\Exception;
 
+use Psr\Container\NotFoundExceptionInterface;
+
 /**
  * This exception is thrown when a non-existent parameter is used.
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */
-class ParameterNotFoundException extends InvalidArgumentException
+class ParameterNotFoundException extends InvalidArgumentException implements NotFoundExceptionInterface
 {
     private $key;
     private $sourceId;

src/Symfony/Component/DependencyInjection/ParameterBag/ContainerBag.php

@@ -0,0 +1,51 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DependencyInjection\ParameterBag;
+
+use Symfony\Component\DependencyInjection\Container;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ */
+class ContainerBag extends FrozenParameterBag implements ContainerBagInterface
+{
+    private $container;
+
+    public function __construct(Container $container)
+    {
+        $this->container = $container;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function all()
+    {
+        return $this->container->getParameterBag()->all();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function get($name)
+    {
+        return $this->container->getParameter($name);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function has($name)
+    {
+        return $this->container->hasParameter($name);
+    }
+}

src/Symfony/Component/DependencyInjection/ParameterBag/ContainerBagInterface.php

@@ -0,0 +1,55 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DependencyInjection\ParameterBag;
+
+use Psr\Container\ContainerInterface;
+use Symfony\Component\DependencyInjection\Exception\ParameterNotFoundException;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ */
+interface ContainerBagInterface extends ContainerInterface
+{
+    /**
+     * Gets the service container parameters.
+     *
+     * @return array An array of parameters
+     */
+    public function all();
+
+    /**
+     * Replaces parameter placeholders (%name%) by their values.
+     *
+     * @param mixed $value A value
+     *
+     * @throws ParameterNotFoundException if a placeholder references a parameter that does not exist
+     */
+    public function resolveValue($value);
+
+    /**
+     * Escape parameter placeholders %.
+     *
+     * @param mixed $value
+     *
+     * @return mixed
+     */
+    public function escapeValue($value);
+
+    /**
+     * Unescape parameter placeholders %.
+     *
+     * @param mixed $value
+     *
+     * @return mixed
+     */
+    public function unescapeValue($value);
+}

src/Symfony/Component/DependencyInjection/Tests/ParameterBag/ContainerBagTest.php

@@ -0,0 +1,65 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DependencyInjection\Tests\ParameterBag;
+
+use PHPUnit\Framework\TestCase;
+use Psr\Container\ContainerInterface;
+use Symfony\Component\DependencyInjection\Container;
+use Symfony\Component\DependencyInjection\ParameterBag\ContainerBag;
+use Symfony\Component\DependencyInjection\ParameterBag\ContainerBagInterface;
+use Symfony\Component\DependencyInjection\ParameterBag\FrozenParameterBag;
+use Symfony\Component\DependencyInjection\ParameterBag\ParameterBag;
+
+class ContainerBagTest extends TestCase
+{
+    /** @var ParameterBag */
+    private $parameterBag;
+    /** @var ContainerBag */
+    private $containerBag;
+
+    public function setUp()
+    {
+        $this->parameterBag = new ParameterBag(array('foo' => 'value'));
+        $this->containerBag = new ContainerBag(new Container($this->parameterBag));
+    }
+
+    public function testGetAllParameters()
+    {
+        $this->assertSame(array('foo' => 'value'), $this->containerBag->all());
+    }
+
+    public function testHasAParameter()
+    {
+        $this->assertTrue($this->containerBag->has('foo'));
+        $this->assertFalse($this->containerBag->has('bar'));
+    }
+
+    public function testGetParameter()
+    {
+        $this->assertSame('value', $this->containerBag->get('foo'));
+    }
+
+    /**
+     * @expectedException \Symfony\Component\DependencyInjection\Exception\InvalidArgumentException
+     */
+    public function testGetParameterNotFound()
+    {
+        $this->containerBag->get('bar');
+    }
+
+    public function testInstanceOf()
+    {
+        $this->assertInstanceOf(FrozenParameterBag::class, $this->containerBag);
+        $this->assertInstanceOf(ContainerBagInterface::class, $this->containerBag);
+        $this->assertInstanceOf(ContainerInterface::class, $this->containerBag);
+    }
+}