Revert "minor symfony#9507 Document the built in env var processors (mcfedr, javiereguiluz)"

This reverts commit c98569d, reversing
changes made to 2a76e88.

Author: javiereguiluz

configuration/external_parameters.rst

@@ -99,181 +99,6 @@ will be used whenever the corresponding environment variable is *not* found:
         // config/services.php
         $container->setParameter('env(DATABASE_HOST)', 'localhost');
 
-Environment Variable Processors
--------------------------------
-
-The values of the environment variables are considered strings by default.
-However, your code may expect other data types, like integers or booleans.
-Symfony solves this problem with *processors*, which modify the contents of the
-given environment variables. The following example uses the integer processor to
-turn the value of the ``HTTP_PORT`` env var into an integer:
-
-.. configuration-block::
-
-    .. code-block:: yaml
-
-        # config/packages/framework.yaml
-        framework:
-            router:
-                http_port: env(int:HTTP_PORT)
-
-    .. code-block:: xml
-
-        <!-- config/packages/framework.xml -->
-        <?xml version="1.0" encoding="UTF-8" ?>
-
-        <container xmlns="http://symfony.com/schema/dic/services"
-            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-            xmlns:framework="http://symfony.com/schema/dic/symfony"
-            xsi:schemaLocation="http://symfony.com/schema/dic/services
-                http://symfony.com/schema/dic/services/services-1.0.xsd
-                http://symfony.com/schema/dic/symfony
-                http://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
-
-            <framework:config>
-                <framework:router http_port="%env(int:HTTP_PORT)%" />
-            </framework:config>
-        </container>
-
-    .. code-block:: php
-
-        // config/packages/doctrine.php
-        $container->loadFromExtension('framework', array(
-            'router' => array(
-                'http_port' => '%env(int:HTTP_PORT)%',
-            )
-        ));
-
-Symfony provides the following env var processors:
-
-``env(string:FOO)``
-    Casts ``FOO`` to a string:
-
-    .. code-block:: yaml
-
-        parameters:
-            env(SECRET): "some_secret"
-        framework:
-           secret: '%env(string:SECRET)%'
-    
-``env(bool:FOO)``
-    Casts ``FOO`` to a bool:
-
-    .. code-block:: yaml
-
-        parameters:
-            env(HTTP_METHOD_OVERRIDE): "true"
-        framework:
-           http_method_override: '%env(bool:HTTP_METHOD_OVERRIDE)%'
-
-``env(int:FOO)``
-    Casts ``FOO`` to an int.
-
-``env(float:FOO)``
-    Casts ``FOO`` to an float.
-
-``env(const:FOO)``
-    Finds the const value named in ``FOO``:
-
-    .. code-block:: yaml
-
-        parameters:
-            env(HEALTH_CHECK_METHOD): "Symfony\Component\HttpFoundation\Request:METHOD_HEAD"
-        security:
-           access_control:
-             - { path: '^/health-check$', methods: '%env(const:HEALTH_CHECK_METHOD)%' }
-
-``env(base64:FOO)``
-    Decodes the content of ``FOO``, which is a base64 encoded string.
-
-``env(json:FOO)``
-    Decodes the content of ``FOO``, which is a JSON encoded string. It returns
-    either an array or ``null``:
-
-    .. code-block:: yaml
-
-        parameters:
-            env(TRUSTED_HOSTS): "['10.0.0.1', '10.0.0.2']"
-        framework:
-           trusted_hosts: '%env(json:TRUSTED_HOSTS)%'
-
-``env(resolve:FOO)``
-    Replaces the string ``FOO`` by the value of a config parameter with the
-    same name:
-
-    .. code-block:: yaml
-
-        parameters:
-            env(HOST): '10.0.0.1'
-            env(SENTRY_DSN): "http://%env(HOST)%/project"
-        sentry:
-            dsn: '%env(resolve:SENTRY_DSN)%'
-    
-``env(csv:FOO)``
-    Decodes the content of ``FOO``, which is a CSV-encoded string:
-
-    .. code-block:: yaml
-
-        parameters:
-            env(TRUSTED_HOSTS): "10.0.0.1, 10.0.0.2"
-        framework:
-           trusted_hosts: '%env(csv:TRUSTED_HOSTS)%'
-
-``env(file:FOO)``
-    Returns the contents of a file whose path is the value of the ``FOO`` env var:
-
-    .. code-block:: yaml
-
-        parameters:
-            env(AUTH_FILE): "../config/auth.json"
-        google:
-           auth: '%env(file:AUTH_FILE)%'
-
-It is also possible to combine any number of processors:
-
-.. code-block:: yaml
-
-    parameters:
-        env(AUTH_FILE): "%kernel.project_dir%/config/auth.json"
-    google:
-        # 1. gets the value of the AUTH_FILE env var
-        # 2. replaces the values of any config param to get the config path
-        # 3. gets the content of the file stored in that path
-        # 4. JSON-decodes the content of the file and returns it
-        auth: '%env(json:file:resolve:AUTH_FILE)%'
-
-Custom Environment Variable Processors
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-It's also possible to add your own processors for environment variables. First,
-create a class that implements 
-:class:`Symfony\\Component\\DependencyInjection\\EnvVarProcessorInterface` and
-then, define a service for that class::
-
-    class LowercasingEnvVarProcessor implements EnvVarProcessorInterface
-    {
-        private $container;
-
-        public function __construct(ContainerInterface $container)
-        {
-            $this->container = $container;
-        }
-
-        public function getEnv($prefix, $name, \Closure $getEnv)
-        {
-            $env = $getEnv($name);
-
-            return strtolower($env);
-        }
-
-        public static function getProvidedTypes()
-        {
-            return [
-                'lowercase' => 'string',
-            ];
-        }
-    }
-
 .. _configuration-env-var-in-prod:
 
 Configuring Environment Variables in Production