Add REDIS_HOST_USER variable to specify a redis user

Author: derhagen

.config/redis.config.php

@@ -5,6 +5,7 @@
     'memcache.locking' => '\OC\Memcache\Redis',
     'redis' => array(
       'host' => getenv('REDIS_HOST'),
+      if (getenv('REDIS_HOST_USER')) { 'user' => getenv('REDIS_HOST_USER'), }
       'password' => getenv('REDIS_HOST_PASSWORD_FILE') ? trim(file_get_contents(getenv('REDIS_HOST_PASSWORD_FILE'))) : (string) getenv('REDIS_HOST_PASSWORD'),
     ),
   );

README.md

@@ -236,6 +236,7 @@ To use Redis for memory caching as well as PHP session storage, specify the foll
 
 - `REDIS_HOST` (not set by default) Name of Redis container
 - `REDIS_HOST_PORT` (default: `6379`) Optional port for Redis, only use for external Redis servers that run on non-standard ports.
+- `REDIS_HOST_USER` (not set by default) Optional username for Redis, only use for external Redis servers that require a user.
 - `REDIS_HOST_PASSWORD` (not set by default) Redis password
 
 Check the [Nextcloud documentation](https://docs.nextcloud.com/server/latest/admin_manual/configuration_server/caching_configuration.html) for more information.