[Cache] merge sections about key rotation into the main one

Author: pableu

cache.rst

@@ -750,6 +750,8 @@ And add it to your :doc:`secret store </configuration/secrets>` as
                 decorates: cache.default_marshaller
                 arguments:
                     - ['%env(base64:CACHE_DECRYPTION_KEY)%']
+                    # use multiple keys in order to rotate them
+                    #- ['%env(base64:CACHE_DECRYPTION_KEY)%', '%env(base64:OLD_CACHE_DECRYPTION_KEY)%']
                     - '@Symfony\Component\Cache\Marshaller\SodiumMarshaller.inner'
 
     .. code-block:: xml
@@ -769,6 +771,8 @@ And add it to your :doc:`secret store </configuration/secrets>` as
                     <argument>redis://localhost</argument>
                     <argument type="collection">
                         <argument>env(base64:CACHE_DECRYPTION_KEY)</argument>
+                        <!-- use multiple keys in order to rotate them -->
+                        <!-- argument>env(base64:OLD_CACHE_DECRYPTION_KEY)</argument -->
                     </argument>
                     <argument type="service" id="Symfony\Component\Cache\Marshaller\SodiumMarshaller.inner"/>
                 </service>
@@ -783,60 +787,13 @@ And add it to your :doc:`secret store </configuration/secrets>` as
         $container->register(SodiumMarshaller::class)
             ->decorate('cache.default_marshaller')
             ->addArgument(['env(base64:CACHE_DECRYPTION_KEY)'])
+            // use multiple keys in order to rotate them
+            // ->addArgument(['env(base64:CACHE_DECRYPTION_KEY)', 'env(base64:OLD_CACHE_DECRYPTION_KEY)'])
             ->addArgument(service('@Symfony\Component\Cache\Marshaller\SodiumMarshaller.inner'));
 
-Rotating the encryption key
-~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
 To rotate your encryption keys but still be able to read existing cache entries,
 add the old encryption key to the service arguments. The first key will be used
 for reading and writing, and the additional key(s) will only be used for reading.
 
-.. configuration-block::
-
-    .. code-block:: yaml
-
-        # config/packages/cache.yaml
-        services:
-            Symfony\Component\Cache\Marshaller\SodiumMarshaller:
-                decorates: cache.default_marshaller
-                arguments:
-                    - ['%env(base64:CACHE_DECRYPTION_KEY)%', '%env(base64:OLD_CACHE_DECRYPTION_KEY)%']
-                    - '@Symfony\Component\Cache\Marshaller\SodiumMarshaller.inner'
-
-    .. code-block:: xml
-
-        <!-- config/packages/cache.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
-                https://symfony.com/schema/dic/services/services-1.0.xsd
-                http://symfony.com/schema/dic/symfony
-                https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
-
-            <services>
-                <service id="Symfony\Component\Cache\Marshaller\SodiumMarshaller" decorates="cache.default_marshaller">
-                    <argument>redis://localhost</argument>
-                    <argument type="collection">
-                        <argument>env(base64:CACHE_DECRYPTION_KEY)</argument>
-                        <argument>env(base64:OLD_CACHE_DECRYPTION_KEY)</argument>
-                    </argument>
-                    <argument type="service" id="Symfony\Component\Cache\Marshaller\SodiumMarshaller.inner"/>
-                </service>
-            </services>
-        </container>
-
-    .. code-block:: php
-
-        // config/packages/cache.php
-        use Symfony\Component\Cache\Marshaller\SodiumMarshaller;
-
-        $container->register(SodiumMarshaller::class)
-            ->decorate('cache.default_marshaller')
-            ->addArgument(['env(base64:CACHE_DECRYPTION_KEY)', 'env(base64:OLD_CACHE_DECRYPTION_KEY)'])
-            ->addArgument(service('@Symfony\Component\Cache\Marshaller\SodiumMarshaller.inner'));
-
 Once all cache items encrypted with the old key have expired, you can remove
 `OLD_CACHE_DECRYPTION_KEY` completely.