1 files changed, 17 insertions, 1 deletions
diff --git a/Backend.hs b/Backend.hs
index eb4a948c4..fb7d5666f 100644
--- a/Backend.hs
+++ b/Backend.hs
@@ -22,7 +22,23 @@ import System.Directory
 import Locations
 import GitRepo
 import Utility
-import Types
+
+-- annexed filenames are mapped into keys
+type Key = FilePath
+
+-- this structure represents a key/value backend
+data Backend = Backend {
+	-- name of this backend
+	name :: String,
+	-- converts a filename to a key
+	getKey :: GitRepo -> FilePath -> IO (Maybe Key),
+	-- stores a file's contents to a key
+	storeFileKey :: GitRepo -> FilePath -> Key -> IO Bool,
+	-- retrieves a key's contents to a file
+	retrieveKeyFile :: Key -> FilePath -> IO Bool,
+	-- removes a key
+	removeKey :: Key -> IO Bool
+}
 
 instance Show Backend where
 	show backend = "Backend { name =\"" ++ (name backend) ++ "\" }"