Deprecate the special SYMFONY__ environment variables

UPGRADE-3.3.md

@@ -153,7 +153,7 @@ FrameworkBundle
    have been deprecated and will be removed in 4.0.
 
  * Extending `ConstraintValidatorFactory` is deprecated and won't be supported in 4.0.
- 
+
  * Class parameters related to routing have been deprecated and will be removed in 4.0.
      * router.options.generator_class
      * router.options.generator_base_class
@@ -168,8 +168,8 @@ FrameworkBundle
    has been deprecated and will be removed in 4.0. Use the `Symfony\Component\HttpKernel\DependencyInjection\ControllerArgumentValueResolverPass`
    class instead.
 
- * The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\RoutingResolverPass` 
-   class has been deprecated and will be removed in 4.0. Use the 
+ * The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\RoutingResolverPass`
+   class has been deprecated and will be removed in 4.0. Use the
    `Symfony\Component\Routing\DependencyInjection\RoutingResolverPass` class instead.
 
 HttpKernel
@@ -187,6 +187,13 @@ HttpKernel
    which will tell the Kernel to use the response code set on the event's
    response object.
 
+ * The `Kernel::getEnvParameters()` method has been deprecated and will be
+   removed in 4.0.
+
+ * The `SYMFONY__` environment variables have been deprecated and they will be
+   no longer processed automatically by Symfony in 4.0. Use the `%env()%` syntax
+   to get the value of any environment variable from configuration files instead.
+
 Process
 -------
 

UPGRADE-4.0.md

@@ -268,7 +268,7 @@ FrameworkBundle
    class instead.
 
  * The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\RoutingResolverPass`
-   class has been removed. Use the 
+   class has been removed. Use the
    `Symfony\Component\Routing\DependencyInjection\RoutingResolverPass` class instead.
 
 HttpFoundation
@@ -321,6 +321,12 @@ HttpKernel
    which will tell the Kernel to use the response code set on the event's
    response object.
 
+ * The `Kernel::getEnvParameters()` method has been removed.
+
+ * The `SYMFONY__` environment variables are no longer processed automatically
+   by Symfony. Use the `%env()%` syntax to get the value of any environment
+   variable from configuration files instead.
+
 Ldap
 ----
 

src/Symfony/Bundle/FrameworkBundle/Tests/Functional/CachePoolsTest.php

@@ -17,16 +17,6 @@ use Symfony\Component\Cache\Exception\InvalidArgumentException;
 
 class CachePoolsTest extends WebTestCase
 {
-    protected function setUp()
-    {
-        $_SERVER['SYMFONY__REDIS_HOST'] = getenv('REDIS_HOST');
-    }
-
-    protected function tearDown()
-    {
-        unset($_SERVER['SYMFONY__REDIS_HOST']);
-    }
-
     public function testCachePools()
     {
         $this->doTestCachePools(array(), FilesystemAdapter::class);

src/Symfony/Bundle/FrameworkBundle/Tests/Functional/app/CachePools/redis_config.yml

@@ -1,10 +1,13 @@
 imports:
     - { resource: ../config/default.yml }
 
+parameters:
+    env(REDIS_HOST): 'localhost'
+
 framework:
     cache:
         app: cache.adapter.redis
-        default_redis_provider: "redis://%redis_host%"
+        default_redis_provider: "redis://%env(REDIS_HOST)%"
         pools:
             cache.pool1:
                 public: true

src/Symfony/Bundle/FrameworkBundle/Tests/Functional/app/CachePools/redis_custom_config.yml

@@ -1,12 +1,15 @@
 imports:
     - { resource: ../config/default.yml }
 
+parameters:
+    env(REDIS_HOST): 'localhost'
+
 services:
     cache.test_redis_connection:
         public: false
         class: Redis
         calls:
-            - [connect, ['%redis_host%']]
+            - [connect, ['%env(REDIS_HOST)%']]
 
     cache.app:
         parent: cache.adapter.redis

src/Symfony/Component/HttpKernel/CHANGELOG.md

@@ -4,6 +4,8 @@ CHANGELOG
 3.3.0
 -----
 
+ * Deprecated `Kernel::getEnvParameters()`
+ * Deprecated the special `SYMFONY__` environment variables
  * added the possibility to change the query string parameter used by `UriSigner`
  * deprecated `LazyLoadingFragmentHandler::addRendererService()`
  * added `SessionListener`

src/Symfony/Component/HttpKernel/Kernel.php

@@ -563,7 +563,7 @@ abstract class Kernel implements KernelInterface, TerminableInterface
                 'kernel.charset' => $this->getCharset(),
                 'kernel.container_class' => $this->getContainerClass(),
             ),
-            $this->getEnvParameters()
+            $this->getEnvParameters(false)
         );
     }
 
@@ -573,12 +573,19 @@ abstract class Kernel implements KernelInterface, TerminableInterface
      * Only the parameters starting with "SYMFONY__" are considered.
      *
      * @return array An array of parameters
+     *
+     * @deprecated since version 3.3, to be removed in 4.0
      */
     protected function getEnvParameters()
     {
+        if (0 === func_num_args() || func_get_arg(0)) {
+            @trigger_error(sprintf('The %s() method is deprecated as of 3.3 and will be removed in 4.0. Use the %%env()%% syntax to get the value of any environment variable from configuration files instead.', __METHOD__), E_USER_DEPRECATED);
+        }
+
         $parameters = array();
         foreach ($_SERVER as $key => $value) {
             if (0 === strpos($key, 'SYMFONY__')) {
+                @trigger_error(sprintf('The support of special environment variables that start with SYMFONY__ (such as "%s") is deprecated as of 3.3 and will be removed in 4.0. Use the %%env()%% syntax instead to get the value of environment variables in configuration files.', $key), E_USER_DEPRECATED);
                 $parameters[strtolower(str_replace('__', '.', substr($key, 9)))] = $value;
             }
         }

src/Symfony/Component/HttpKernel/Tests/KernelTest.php

@@ -742,6 +742,25 @@ EOF;
         $this->assertEquals('_123', $kernel->getName());
     }
 
+    /**
+     * @group legacy
+     * @expectedDeprecation The Symfony\Component\HttpKernel\Kernel::getEnvParameters() method is deprecated as of 3.3 and will be removed in 4.0. Use the %cenv()%c syntax to get the value of any environment variable from configuration files instead.
+     * @expectedDeprecation The support of special environment variables that start with SYMFONY__ (such as "SYMFONY__FOO__BAR") is deprecated as of 3.3 and will be removed in 4.0. Use the %cenv()%c syntax instead to get the value of environment variables in configuration files.
+     */
+    public function testSymfonyEnvironmentVariables()
+    {
+        $_SERVER['SYMFONY__FOO__BAR'] = 'baz';
+
+        $kernel = $this->getKernel();
+        $method = new \ReflectionMethod($kernel, 'getEnvParameters');
+        $method->setAccessible(true);
+
+        $envParameters = $method->invoke($kernel);
+        $this->assertSame('baz', $envParameters['foo.bar']);
+
+        unset($_SERVER['SYMFONY__FOO__BAR']);
+    }
+
     /**
      * Returns a mock for the BundleInterface.
      *