1 files changed, 47 insertions, 0 deletions
diff --git a/Backend/URL.hs b/Backend/URL.hs
new file mode 100644
index 000000000..c9b6ab6df
--- /dev/null
+++ b/Backend/URL.hs
@@ -0,0 +1,47 @@
+{- git-annex "URL" backend
+ - -}
+
+module Backend.URL (backend) where
+
+import Control.Exception
+import Control.Monad.State (liftIO)
+import Data.String.Utils
+import System.Cmd
+import System.Cmd.Utils
+import System.Exit
+
+import TypeInternals
+import Core
+
+backend = Backend {
+	name = "URL",
+	getKey = keyValue,
+	storeFileKey = dummyStore,
+	retrieveKeyFile = downloadUrl,
+	removeKey = dummyOk,
+	hasKey = dummyOk
+}
+
+-- cannot generate url from filename
+keyValue :: FilePath -> Annex (Maybe Key)
+keyValue file = return Nothing
+
+-- cannot change url contents
+dummyStore :: FilePath -> Key -> Annex Bool
+dummyStore file url = return False
+
+-- allow keys to be removed; presumably they can always be downloaded again
+dummyOk :: Key -> Annex Bool
+dummyOk url = return True
+
+downloadUrl :: Key -> FilePath -> Annex Bool
+downloadUrl key file = do
+	showNote "downloading"
+	liftIO $ putStrLn "" -- make way for curl progress bar
+	result <- liftIO $ (try curl::IO (Either SomeException ()))
+	case result of
+		Left err -> return False
+		Right succ -> return True
+	where
+		curl = safeSystem "curl" ["-#", "-o", file, url]
+		url = join ":" $ drop 1 $ split ":" $ show key