diff --git a/pyinfra/storage/adapter.py b/pyinfra/storage/adapter.py
index 6a30f5e..61b51e8 100644
--- a/pyinfra/storage/adapter.py
+++ b/pyinfra/storage/adapter.py
@@ -1,7 +1,22 @@
-class StorageAdapter:
+from abc import ABC, abstractmethod
+
+
+class StorageAdapter(ABC):
     def __init__(self, client):
         self.__client = client
 
+    @abstractmethod
+    def put(self, bucket_name, object_name, data):
+        pass
 
+    @abstractmethod
+    def get(self, bucket_name, object_name):
+        pass
 
+    @abstractmethod
+    def get_all(self, bucket_name):
+        pass
 
+    @abstractmethod
+    def purge(self, bucket_name):
+        pass
diff --git a/pyinfra/test/storage/adapter_mock.py b/pyinfra/test/storage/adapter_mock.py
index 71f69ef..34280fe 100644
--- a/pyinfra/test/storage/adapter_mock.py
+++ b/pyinfra/test/storage/adapter_mock.py
@@ -1,10 +1,12 @@
+from pyinfra.storage.adapter import StorageAdapter
 from pyinfra.test.storage.client_mock import StorageClientMock
 
 
-class StorageAdapterMock:
+class StorageAdapterMock(StorageAdapter):
     def __init__(self, client: StorageClientMock):
         assert isinstance(client, StorageClientMock)
-        self.__client = client
+        super().__init__(client=client)
+        self.__client = self._StorageAdapter__client
 
     def put(self, bucket_name, object_name, data):
         return self.__client.put(bucket_name, object_name, data)
diff --git a/pyinfra/test/storage/client_mock.py b/pyinfra/test/storage/client_mock.py
index 69d0695..cfc3eaa 100644
--- a/pyinfra/test/storage/client_mock.py
+++ b/pyinfra/test/storage/client_mock.py
@@ -16,4 +16,3 @@ class StorageClientMock:
 
     def purge(self, bucket_name):
         self.__data[bucket_name] = {}
-