[Cache] Revert some changes merged made in 5.x branch

Author: javiereguiluz

components/cache/adapters/redis_adapter.rst

@@ -59,18 +59,24 @@ helper method allows creating and configuring the Redis client class instance us
         'redis://localhost'
     );
 
-The DSN can specify either an IP/host (and an optional port) or a socket path, as
-well as a database index. To enable TLS for connections, the scheme ``redis`` must
-be replaced by ``rediss`` (the second ``s`` means "secure").
+The DSN can specify either an IP/host (and an optional port) or a socket path, as well as a
+password and a database index. To enable TLS for connections, the scheme ``redis`` must be
+replaced by ``rediss`` (the second ``s`` means "secure").
 
 .. note::
 
-    A `Data Source Name (DSN)`_ for this adapter must use the following format.
+    A `Data Source Name (DSN)`_ for this adapter must use either one of the following formats.
 
     .. code-block:: text
 
         redis[s]://[pass@][ip|host|socket[:port]][/db-index]
 
+    .. code-block:: text
+
+        redis[s]:[[user]:pass@]?[ip|host|socket[:port]][&params]
+
+    Values for placeholders ``[user]``, ``[:port]``, ``[/db-index]`` and ``[&params]`` are optional.
+
 Below are common examples of valid DSNs showing a combination of available values::
 
     use Symfony\Component\Cache\Adapter\RedisAdapter;
@@ -87,8 +93,11 @@ Below are common examples of valid DSNs showing a combination of available value
     // socket "/var/run/redis.sock" and auth "bad-pass"
     RedisAdapter::createConnection('redis://bad-pass@/var/run/redis.sock');
 
-    // a single DSN can define multiple servers using the following syntax:
-    // host[hostname-or-IP:port] (where port is optional). Sockets must include a trailing ':'
+    // host "redis1" (docker container) with alternate DSN syntax and selecting database index "3"
+    RedisAdapter::createConnection('redis:?host[redis1:6379]&dbindex=3');
+
+    // providing credentials with alternate DSN syntax
+    RedisAdapter::createConnection('redis:default:verysecurepassword@?host[redis1:6379]&dbindex=3');
 
     // a single DSN can also define multiple servers
     RedisAdapter::createConnection(
@@ -103,6 +112,16 @@ parameter to set the name of your service group::
         'redis:?host[redis1:26379]&host[redis2:26379]&host[redis3:26379]&redis_sentinel=mymaster'
     );
 
+    // providing credentials
+    RedisAdapter::createConnection(
+        'redis:default:verysecurepassword@?host[redis1:26379]&host[redis2:26379]&host[redis3:26379]&redis_sentinel=mymaster'
+    );
+
+    // providing credentials and selecting database index "3"
+    RedisAdapter::createConnection(
+        'redis:default:verysecurepassword@?host[redis1:26379]&host[redis2:26379]&host[redis3:26379]&redis_sentinel=mymaster&dbindex=3'
+    );
+
 .. note::
 
     See the :class:`Symfony\\Component\\Cache\\Traits\\RedisTrait` for more options