Add metabase and write_cache operations

Signed-off-by: Andrey Berezin <a.berezin@yadro.com>

src/frostfs_testlib/storage/dataclasses/node_base.py

@@ -1,6 +1,8 @@
 from abc import ABC, abstractmethod
 from dataclasses import dataclass
-from typing import Optional, TypedDict, TypeVar
+from typing import Optional, Tuple, TypedDict, TypeVar
+
+import yaml
 
 from frostfs_testlib.hosting.config import ServiceConfig
 from frostfs_testlib.hosting.interfaces import Host
@@ -84,12 +86,29 @@ class NodeBase(ABC):
             ConfigAttributes.CONFIG_PATH,
         )
 
-    def get_wallet_config_path(self):
+    def get_wallet_config_path(self) -> str:
         return self._get_attribute(
             ConfigAttributes.LOCAL_WALLET_CONFIG,
             ConfigAttributes.WALLET_CONFIG,
         )
 
+    def get_config(self) -> Tuple[str, dict]:
+        config_file_path = self._get_attribute(ConfigAttributes.CONFIG_PATH)
+        shell = self.host.get_shell()
+
+        result = shell.exec(f"cat {config_file_path}")
+        config_text = result.stdout
+
+        config = yaml.safe_load(config_text)
+        return config_file_path, config
+
+    def save_config(self, new_config: dict) -> None:
+        config_file_path = self._get_attribute(ConfigAttributes.CONFIG_PATH)
+        shell = self.host.get_shell()
+
+        config_str = yaml.dump(new_config)
+        shell.exec(f"echo '{config_str}' | sudo tee {config_file_path}")
+
     def get_wallet_public_key(self):
         storage_wallet_path = self.get_wallet_path()
         storage_wallet_pass = self.get_wallet_password()