Improve error handling; misc

minio-hs.cabal

@@ -64,6 +64,7 @@ library
                      , MultiParamTypeClasses
                      , MultiWayIf
                      , RankNTypes
+                     , ScopedTypeVariables
                      , TypeFamilies
                      , TupleSections
 

src/Lib/Prelude.hs

@@ -11,5 +11,6 @@ module Lib.Prelude
 import Protolude as Exports
 
 import Data.Time as Exports (UTCTime)
+import Data.Maybe as Exports (catMaybes, listToMaybe)
 
 import Control.Monad.Catch as Exports (throwM, MonadThrow, MonadCatch)

src/Network/Minio/PutObject.hs

@@ -5,7 +5,6 @@ module Network.Minio.PutObject
   ) where
 
 
-import qualified Control.Monad.Trans.Resource as R
 import qualified Data.Conduit as C
 import qualified Data.Conduit.Binary as CB
 import qualified Data.List as List
@@ -44,15 +43,16 @@ data ObjectData m = ODFile FilePath (Maybe Int64) -- ^ Takes filepath and option
 -- objects of all sizes, and even if the object size is unknown.
 putObject :: Bucket -> Object -> ObjectData Minio -> Minio ETag
 putObject b o (ODFile fp sizeMay) = do
-  isSeekable <- isFileSeekable fp
+  hResE <- withNewHandle fp $ \h -> do
+    isSeekable <- isHandleSeekable h
+    handleSizeMay <- getFileSize h
+    return (isSeekable, handleSizeMay)
 
-  -- FIXME: allocateReadFile may return exceptions and shortcircuit
-  finalSizeMay <- maybe (do (rKey, h) <- allocateReadFile fp
-                            sizeE <- getFileSize h
-                            R.release rKey
-                            return $ hush $ sizeE
-                        )
-                  (return . Just) sizeMay
+  (isSeekable, handleSizeMay) <- either (const $ return (False, Nothing)) return
+                                 hResE
+
+  -- prefer given size to queried size.
+  let finalSizeMay = listToMaybe $ catMaybes [sizeMay, handleSizeMay]
 
   case finalSizeMay of
     -- unable to get size, so assume non-seekable file and max-object size
@@ -62,11 +62,9 @@ putObject b o (ODFile fp sizeMay) = do
     -- got file size, so check for single/multipart upload
     Just size ->
       if | size <= 64 * oneMiB -> do
-             (rKey, h) <- allocateReadFile fp
-             etag <- putObjectSingle b o [] h 0 size
-             R.release rKey
-             return etag
-         | size > maxObjectSize -> R.throwM $ ValidationError $
+             resE <- withNewHandle fp (\h -> putObjectSingle b o [] h 0 size)
+             either throwM return resE
+         | size > maxObjectSize -> throwM $ ValidationError $
                                    MErrVPutSizeExceeded size
          | isSeekable -> parallelMultipartUpload b o fp size
          | otherwise -> sequentialMultipartUpload b o (Just size) $
@@ -93,18 +91,18 @@ parallelMultipartUpload b o filePath size = do
   uploadId <- newMultipartUpload b o []
 
   -- perform upload with 10 threads
-  uploadedParts <- limitedMapConcurrently 10 (uploadPart uploadId) partSizeInfo
+  uploadedPartsE <- limitedMapConcurrently 10 (uploadPart uploadId) partSizeInfo
 
-  completeMultipartUpload b o uploadId uploadedParts
+  -- if there were any errors, rethrow exception.
+  mapM_ throwM $ lefts uploadedPartsE
+
+  -- if we get here, all parts were successfully uploaded.
+  completeMultipartUpload b o uploadId $ rights uploadedPartsE
   where
-    uploadPart uploadId (partNum, offset, sz) = do
-      (rKey, h) <- allocateReadFile filePath
-      pInfo <- putObjectPart b o uploadId partNum [] $ PayloadH h offset sz
-      R.release rKey
-      return pInfo
+    uploadPart uploadId (partNum, offset, sz) = withNewHandle filePath $
+      \h -> putObjectPart b o uploadId partNum [] $ PayloadH h offset sz
 
--- | Upload multipart object from conduit source sequentially without
--- object size information.
+-- | Upload multipart object from conduit source sequentially
 sequentialMultipartUpload :: Bucket -> Object -> Maybe Int64
                           -> C.Producer Minio ByteString -> Minio ETag
 sequentialMultipartUpload b o sizeMay src = do
@@ -145,3 +143,15 @@ sequentialMultipartUpload b o sizeMay src = do
                 pInfo <- putObjectPart b o uid partNum [] $
                          PayloadBS $ LB.toStrict buf
                 return $ reverse (pInfo:u)
+
+-- | Looks for incomplete uploads for an object. Returns the first one
+-- if there are many.
+getExistingUpload :: Bucket -> Object
+                  -> Minio (Maybe (UploadId, [ListPartInfo]))
+getExistingUpload b o = do
+  uploadsRes <- listIncompleteUploads' b (Just o) Nothing Nothing Nothing
+  case uiUploadId <$> listToMaybe (lurUploads uploadsRes) of
+    Nothing -> return Nothing
+    Just uid -> do
+      lpr <- listIncompleteParts' b o uid Nothing Nothing
+      return $ Just (uid, lprParts lpr)

src/Network/Minio/S3API.hs

@@ -213,7 +213,7 @@ abortMultipartUpload bucket object uploadId = do
 
 -- | List incomplete multipart uploads.
 listIncompleteUploads' :: Bucket -> Maybe Text -> Maybe Text -> Maybe Text
-                      -> Maybe Text -> Minio ListUploadsResult
+                       -> Maybe Text -> Minio ListUploadsResult
 listIncompleteUploads' bucket prefix delimiter keyMarker uploadIdMarker = do
   resp <- executeRequest $ def { riMethod = HT.methodGet
                                , riBucket = Just bucket

src/Network/Minio/Utils.hs

@@ -5,6 +5,7 @@ import qualified Control.Concurrent.QSem as Q
 import qualified Control.Exception.Lifted as ExL
 import           Control.Monad.Trans.Control (liftBaseOp_, StM)
 import qualified Control.Monad.Trans.Resource as R
+import qualified Control.Monad.Catch as MC
 import qualified Data.Conduit as C
 import           Data.Text.Encoding.Error (lenientDecode)
 import qualified Network.HTTP.Client as NClient
@@ -26,17 +27,43 @@ allocateReadFile fp = do
     openReadFile f = ExL.try $ IO.openBinaryFile f IO.ReadMode
     cleanup = either (const $ return ()) IO.hClose
 
+-- | Queries the file size from the handle. Catches any file operation
+-- exceptions and returns Nothing instead.
 getFileSize :: (R.MonadResourceBase m, R.MonadResource m)
-            => Handle -> m (Either IOException Int64)
-getFileSize h = ExL.try $ liftIO $ fromIntegral <$> IO.hFileSize h
+            => Handle -> m (Maybe Int64)
+getFileSize h = do
+  resE <- liftIO $ try $ fromIntegral <$> IO.hFileSize h
+  case resE of
+    Left (_ :: IOException) -> return Nothing
+    Right s -> return $ Just s
 
-isFileSeekable :: (R.MonadResource m, R.MonadResourceBase m)
-               => FilePath -> m Bool
-isFileSeekable fp = do
-  (rKey, h) <- allocateReadFile fp
+-- | Queries if handle is seekable. Catches any file operation
+-- exceptions and return False instead.
+isHandleSeekable :: (R.MonadResource m, R.MonadResourceBase m)
+               => Handle -> m Bool
+isHandleSeekable h = do
   resE <- liftIO $ try $ IO.hIsSeekable h
-  R.release rKey
-  either (throwM . MEFile) return resE
+  case resE of
+    Left (_ :: IOException) -> return False
+    Right v -> return v
+
+-- | Helper function that opens a handle to the filepath and performs
+-- the given action on it. Exceptions of type MError are caught and
+-- returned - both during file handle allocation and when the action
+-- is run.
+withNewHandle :: (R.MonadResourceBase m, R.MonadResource m, MonadCatch m)
+              => FilePath -> (Handle -> m a) -> m (Either MError a)
+withNewHandle fp fileAction = do
+  -- opening a handle can throw MError exception.
+  handleE <- MC.try $ allocateReadFile fp
+  either (return . Left) doAction handleE
+  where
+    doAction (rkey, h) = do
+      -- fileAction may also throw MError exception, so we catch and
+      -- return it.
+      resE <- MC.try $ fileAction h
+      R.release rkey
+      return resE
 
 
 lookupHeader :: HT.HeaderName -> [HT.Header] -> Maybe ByteString