Merge branch '414-can-t-connect-to-redis-with-default-configuration' into 'master'

Resolve "Can't connect to Redis with default configuration"

Closes #414

See merge request !553

aleksis/core/settings.py

@@ -213,11 +213,11 @@ merge_app_settings("DATABASES", DATABASES, False)
 REDIS_HOST = _settings.get("redis.host", "localhost")
 REDIS_PORT = _settings.get("redis.port", 6379)
 REDIS_DB = _settings.get("redis.database", 0)
-REDIS_USER = _settings.get("redis.user", "default")
 REDIS_PASSWORD = _settings.get("redis.password", None)
+REDIS_USER = _settings.get("redis.user", None if REDIS_PASSWORD is None else "default")
 
 REDIS_URL = (
-    f"redis://{REDIS_USER}{':'+REDIS_PASSWORD if REDIS_PASSWORD else ''}@"
+    f"redis://{REDIS_USER+':'+REDIS_PASSWORD+'@' if REDIS_USER else ''}"
     f"{REDIS_HOST}:{REDIS_PORT}/{REDIS_DB}"
 )