fix(backups): return type of encryption key

selfprivacy_api/backup/local_secret.py

@@ -15,13 +15,13 @@ redis = RedisPool().get_connection()
 
 class LocalBackupSecret:
     @staticmethod
-    def get():
+    def get() -> str:
         """A secret string which backblaze/other clouds do not know.
         Serves as encryption key.
         """
         if not LocalBackupSecret.exists():
             LocalBackupSecret.reset()
-        return redis.get(REDIS_KEY)
+        return redis.get(REDIS_KEY)  # type: ignore
 
     @staticmethod
     def set(secret: str):

selfprivacy_api/backup/providers/provider.py

@@ -12,6 +12,8 @@ class AbstractBackupProvider(ABC):
     def backuper(self) -> AbstractBackuper:
         raise NotImplementedError
 
+    name = "NONE"
+
     def __init__(self, login="", key="", location="", repo_id=""):
         self.backuper.set_creds(login, key, location)
         self.login = login

selfprivacy_api/graphql/queries/backup.py

@@ -28,10 +28,9 @@ class BackupConfiguration:
 class Backup:
     @strawberry.field
     def configuration(self) -> BackupConfiguration:
-        encryption_key = LocalBackupSecret.get()
         return BackupConfiguration(
             provider=BackupProvider[Backups.provider().name],
-            encryption_key=encryption_key.decode() if encryption_key else "",
+            encryption_key=LocalBackupSecret.get(),
             is_initialized=Backups.is_initted(),
             autobackup_period=Backups.autobackup_period_minutes(),
             location_name=Backups.provider().location,