fix stream input logger (#100)

Logger tried to decode UTF8 at packet boundaries

pontarius-xmpp.cabal

@@ -156,6 +156,7 @@ Test-Suite tests
                , Tests.Arbitrary.Xmpp
                , Tests.Parsers
                , Tests.Picklers
+               , Tests.Stream
   ghc-options: -Wall -O2 -fno-warn-orphans
 
 Test-Suite doctest

source/Network/Xmpp/Stream.hs

@@ -31,6 +31,7 @@ import           Data.Ord
 import           Data.Text (Text)
 import qualified Data.Text as Text
 import qualified Data.Text.Encoding as Text
+import qualified Data.Text.Encoding.Error as Text
 import           Data.Void (Void)
 import           Data.XML.Pickle
 import           Data.XML.Types
@@ -240,22 +241,41 @@ restartStream = do
 
 
 -- Creates a conduit from a StreamHandle
-sourceStreamHandle :: (MonadIO m, MonadError XmppFailure m)
+sourceStreamHandleRaw :: (MonadIO m, MonadError XmppFailure m)
                       => StreamHandle -> ConduitM i ByteString m ()
-sourceStreamHandle s = loopRead $ streamReceive s
+sourceStreamHandleRaw s = forever . read $ streamReceive s
   where
-    loopRead rd = do
+    read rd = do
         bs' <- liftIO (rd 4096)
         bs <- case bs' of
             Left e -> throwError e
             Right r -> return r
-        if BS.null bs
-            then return ()
-            else do
-               liftIO $ debugM "Pontarius.Xmpp" $ "in: " ++
-                              (Text.unpack . Text.decodeUtf8 $ bs)
-               yield bs
-               loopRead rd
+        yield bs
+
+sourceStreamHandle :: (MonadIO m, MonadError XmppFailure m)
+                      => StreamHandle -> ConduitM i ByteString m ()
+sourceStreamHandle sh = sourceStreamHandleRaw sh $= logInput
+
+logInput :: MonadIO m => ConduitM ByteString ByteString m ()
+logInput = go Nothing
+  where
+    go mbDec = do
+        mbBs <- await
+        case mbBs of
+         Nothing -> return ()
+         Just bs -> do
+           let decode = case mbDec of
+                         Nothing -> Text.streamDecodeUtf8With Text.lenientDecode
+                         Just d -> d
+               (Text.Some out leftover cont) = decode bs
+               cont' = if BS.null leftover
+                       then Nothing
+                       else Just cont
+           unless (Text.null out) $
+               liftIO $ debugM "Pontarius.Xmpp"
+                                $ "in: " ++ Text.unpack out
+           yield bs
+           go cont'
 
 -- We buffer sources because we don't want to lose data when multiple
 -- xml-entities are sent with the same packet and we don't want to eternally

tests/Main.hs

@@ -4,8 +4,10 @@ import Test.Tasty
 
 import Tests.Parsers
 import Tests.Picklers
+import Tests.Stream
 
 main :: IO ()
 main = defaultMain $ testGroup "root" [ parserTests
                                       , picklerTests
+                                      , streamTests
                                       ]

tests/Tests/Stream.hs

@@ -3,13 +3,15 @@
 
 module Tests.Stream where
 
+import           Control.Monad.Trans
 import           Data.Conduit
 import qualified Data.Conduit.List as CL
 import           Data.XML.Types
 import           Test.Hspec
-import           Test.Tasty.TH
 import           Test.Tasty
+import           Test.Tasty.HUnit
 import           Test.Tasty.Hspec
+import           Test.Tasty.TH
 
 import           Network.Xmpp.Stream
 
@@ -27,7 +29,7 @@ junk = [ EventBeginDocument
 
 beginElem = EventBeginElement "foo" []
 
-case_ThrowOutJunk = do
+case_ThrowOutJunk = hspec . describe "throwOutJunk" $ do
     it "drops everything but EvenBeginElement" $ do
         res <- CL.sourceList junk $$ throwOutJunk >> await
         res `shouldBe` Nothing
@@ -36,5 +38,10 @@ case_ThrowOutJunk = do
                              $$ throwOutJunk >> CL.consume
         res `shouldBe` (beginElem : junk)
 
-testStreams :: TestTree
-testStreams = $testGroupGenerator
+case_LogInput = hspec . describe "logInput" $ do
+    it "Can handle split UTF8 codepoints" $ do
+        res <- CL.sourceList ["\209","\136"] $= logInput $$ CL.consume
+        res `shouldBe` ["\209","\136"]
+
+streamTests :: TestTree
+streamTests = $testGroupGenerator