new version

app/Main.hs

@@ -1,9 +1,10 @@
+module Main where
+
 import Path
-import qualified Data.ByteString.Lazy as BS
 import qualified Data.Text as T
 import Data.Attoparsec.Text (parseOnly, endOfInput, eitherP)
 import Data.Attoparsec.Path (absFilePath, relFilePath, absDirPath)
-import Data.Conduit ((=$=), runConduit)
+import Data.Conduit ((.|), runConduit)
 import Data.Conduit.Combinators (stdout)
 import System.INotify (initINotify, removeWatch, killINotify)
 import System.File.Follow (follow)
@@ -14,9 +15,10 @@ import Control.Exception (bracket)
 import Control.Concurrent (threadDelay)
 
 
+main :: IO ()
 main = do
-  [f] <- getArgs
-  f <- case parseOnly (eitherP absFilePath relFilePath <* endOfInput) (T.pack f) of
+  [filePath] <- getArgs
+  f <- case parseOnly (eitherP absFilePath relFilePath <* endOfInput) (T.pack filePath) of
           Left e -> error e
           Right eAR -> case eAR of
             Left a -> pure a
@@ -27,4 +29,7 @@ main = do
                 Right d' ->
                   pure (d' </> r)
   i <- initINotify
-  bracket (follow i f (\source -> runConduit $ source =$= stdout)) (\watch -> removeWatch watch >> killINotify i) $ \_ -> forever $ threadDelay 50000
+  let obtain = follow i f $ \source -> runConduit (source .| stdout)
+      release watch = removeWatch watch >> killINotify i
+  bracket obtain release $ \_ ->
+    forever (threadDelay 50000) -- run forever

follow-file.cabal

@@ -1,53 +1,73 @@
-Name:                   follow-file
-Version:                0.0.2
-Author:                 Athan Clark <athan.clark@gmail.com>
-Maintainer:             Athan Clark <athan.clark@gmail.com>
-License:                BSD3
-License-File:           LICENSE
-Synopsis:               Be notified when a file gets appended, solely with what was added.
-Description:
-    See module for docs
-Cabal-Version:          >= 1.10
-Build-Type:             Simple
-Category:               Filesystem
+-- This file has been generated from package.yaml by hpack version 0.21.2.
+--
+-- see: https://github.com/sol/hpack
+--
+-- hash: 2237e4036e920a20255f1af7b7256b4210fd90eddba2b0938e9df217cf29ccb7
 
+name:           follow-file
+version:        0.0.3
+synopsis:       Be notified when a file gets appended, solely with what was added. Warning - only works on linux and for files that are strictly appended, like log files.
+description:    Please see the README on Github at <https://github.com/athanclark/follow-file#readme>
+category:       Filesystem
+homepage:       https://github.com/athanclark/follow-file#readme
+bug-reports:    https://github.com/athanclark/follow-file/issues
+maintainer:     Athan Clark <athan.clark@gmail.com>
+license:        BSD3
+license-file:   LICENSE
+build-type:     Simple
+cabal-version:  >= 1.10
 
-Library
-  Default-Language:     Haskell2010
-  HS-Source-Dirs:       src
-  GHC-Options:          -Wall
-  Exposed-Modules:      System.File.Follow
-  Build-Depends:        base >= 4.8 && < 5
-                      , attoparsec
-                      , attoparsec-path
-                      , bytestring
-                      , conduit
-                      , directory
-                      , exceptions
-                      , hinotify
-                      , monad-control
-                      , mtl
-                      , path
-                      , text
-                      , unix
-                      , utf8-string
+source-repository head
+  type: git
+  location: https://github.com/athanclark/follow-file
 
-Executable follow-file
-  Default-Language:     Haskell2010
-  Hs-Source-Dirs:       app
-  Main-is:              Main.hs
-  Build-Depends:        base
-                      , bytestring
-                      , follow-file
-                      , path
-                      , text
-                      , attoparsec
-                      , attoparsec-path
-                      , hinotify
-                      , conduit
-                      , conduit-combinators
-                      , directory
+library
+  exposed-modules:
+      System.File.Follow
+  other-modules:
+      Paths_follow_file
+  hs-source-dirs:
+      src
+  ghc-options: -Wall
+  build-depends:
+      attoparsec
+    , attoparsec-path
+    , base >=4.11 && <5
+    , bytestring
+    , conduit
+    , directory
+    , exceptions
+    , hinotify >=0.4
+    , monad-control
+    , mtl
+    , path
+    , text
+    , unix
+    , utf8-string
+  default-language: Haskell2010
 
-Source-Repository head
-  Type:                 git
-  Location:             https://github.com/athanclark/follow-file
+executable follow-file
+  main-is: Main.hs
+  other-modules:
+      Paths_follow_file
+  hs-source-dirs:
+      app
+  ghc-options: -Wall -threaded -rtsopts -Wall -with-rtsopts=-N
+  build-depends:
+      attoparsec
+    , attoparsec-path
+    , base
+    , bytestring
+    , conduit
+    , conduit-combinators
+    , directory
+    , exceptions
+    , follow-file
+    , hinotify
+    , monad-control
+    , mtl
+    , path
+    , text
+    , unix
+    , utf8-string
+  default-language: Haskell2010

package.yaml

@@ -0,0 +1,52 @@
+name: follow-file
+version: 0.0.3
+synopsis: Be notified when a file gets appended, solely with what was added. Warning - only works on linux and for files that are strictly appended, like log files.
+description: Please see the README on Github at <https://github.com/athanclark/follow-file#readme>
+maintainer: Athan Clark <athan.clark@gmail.com>
+license: BSD3
+github: athanclark/follow-file
+category: Filesystem
+
+ghc-options: -Wall
+
+dependencies:
+  - base >= 4.11 && < 5
+  - attoparsec
+  - attoparsec-path
+  - bytestring
+  - conduit
+  - directory
+  - exceptions
+  - hinotify >= 0.4
+  - monad-control
+  - mtl
+  - path
+  - text
+  - unix
+  - utf8-string
+
+library:
+  source-dirs: src
+
+executables:
+  follow-file:
+    ghc-options:
+      - -threaded
+      - -rtsopts
+      - -Wall
+      - -with-rtsopts=-N
+    main: Main.hs
+    source-dirs:
+      - app
+    dependencies:
+      - base
+      - follow-file
+      - bytestring
+      - path
+      - text
+      - attoparsec
+      - attoparsec-path
+      - hinotify
+      - conduit
+      - conduit-combinators
+      - directory

src/System/File/Follow.hs

@@ -12,17 +12,18 @@ import Data.IORef (IORef, newIORef, readIORef, writeIORef)
 import qualified Data.ByteString.Lazy.Internal as LBS
 import qualified Data.ByteString.Internal as BS
 import qualified Data.ByteString.UTF8 as BS8
-import qualified Data.Text as T
+import qualified Data.Text.Encoding as T
 import Data.Attoparsec.Text (parseOnly, endOfInput)
 import Data.Attoparsec.Path (relFilePath)
-import Data.Conduit (Producer, yield)
+import Data.Conduit (ConduitT, yield)
 import Control.Monad (void)
 import Control.Monad.IO.Class (MonadIO (liftIO))
 import Control.Monad.Catch (MonadMask, bracket)
 import Control.Monad.Trans.Control (MonadBaseControl (liftBaseWith))
 import Path (Path, Abs, File, filename, parent, toFilePath)
 import System.Posix.IO.ByteString (fdReadBuf, openFd, OpenMode (ReadOnly), defaultFileFlags, closeFd, fdSeek)
 import System.Posix.Types (FileOffset)
+import System.Posix.ByteString.FilePath (RawFilePath)
 import System.Posix.Files.ByteString (fileSize, getFileStatus)
 import System.Directory (doesFileExist)
 import System.INotify (INotify, addWatch, Event (..), EventVariety (..), WatchDescriptor)
@@ -38,7 +39,7 @@ follow :: ( MonadIO m
           )
        => INotify
        -> Path Abs File
-       -> (Producer m BS.ByteString -> m ()) -- ^ Monadic state of @m@ is thrown away for each invocation, not synchronously interleaved.
+       -> (ConduitT i BS.ByteString m () -> m ()) -- ^ Monadic state of @m@ is thrown away for each invocation, not synchronously interleaved.
        -> m WatchDescriptor
 follow inotify file f = do
   let file' = toFilePath file
@@ -67,19 +68,25 @@ follow inotify file f = do
       stop = do
         liftIO (writeIORef positionRef 0)
         f (yield mempty)
-  liftBaseWith $ \runInBase -> addWatch inotify [Modify, Create, Delete] (toFilePath $ parent file) $ \e ->
-    let isFile filePath = parseOnly (relFilePath <* endOfInput) (T.pack filePath) == Right (filename file)
+  liftBaseWith $ \runInBase -> addWatch inotify [Modify, Create, Delete] (BS8.fromString $ toFilePath $ parent file) $ \e ->
+    let isFile :: RawFilePath -> Bool
+        isFile filePath = parseOnly (relFilePath <* endOfInput) (T.decodeUtf8 filePath) == Right (filename file)
     in  case e of
-          Created {filePath}  | isFile filePath -> void $ runInBase go
-                              | otherwise -> pure ()
-          Deleted {filePath}  | isFile filePath -> void $ runInBase stop
-                              | otherwise -> pure ()
-          Modified {maybeFilePath}  | (isFile <$> maybeFilePath) == Just True -> void $ runInBase go
-                                    | otherwise -> pure ()
-          MovedIn {filePath}  | isFile filePath -> void $ runInBase go
-                              | otherwise -> pure ()
-          MovedOut {filePath}   | isFile filePath -> void $ runInBase go
-                                | otherwise -> pure ()
+          Created {filePath}
+            | isFile filePath -> void $ runInBase go
+            | otherwise -> pure ()
+          Deleted {filePath}
+            | isFile filePath -> void $ runInBase stop
+            | otherwise -> pure ()
+          Modified {maybeFilePath}
+            | (isFile <$> maybeFilePath) == Just True -> void $ runInBase go
+            | otherwise -> pure ()
+          MovedIn {filePath}
+            | isFile filePath -> void $ runInBase go
+            | otherwise -> pure ()
+          MovedOut {filePath}
+            | isFile filePath -> void $ runInBase go
+            | otherwise -> pure ()
           DeletedSelf -> error "containing folder deleted"
           Unmounted -> error "containing folder unmounted"
           QOverflow -> error "queue overflow"

stack.yaml

@@ -15,7 +15,7 @@
 # resolver:
 #  name: custom-snapshot
 #  location: "./custom-snapshot.yaml"
-resolver: nightly-2016-06-30
+resolver: lts-12.0
 
 # User packages to be built.
 # Various formats can be used as shown in the example below.
@@ -40,7 +40,7 @@ packages:
 # Dependency packages to be pulled from upstream that are not in the resolver
 # (e.g., acme-missiles-0.3)
 extra-deps:
-  - attoparsec-path-0.0.0.1
+  - hinotify-0.4
 
 # Override default flag values for local packages and extra-deps
 flags: {}