keera-hails-reactive-fs (empty) → 0.0.3.3

raw patch · 4 files changed

+138/−0 lines, 4 filesdep +basedep +directorydep +fsnotifysetup-changed

Dependencies added: base, directory, fsnotify, keera-hails-reactivevalues, system-filepath

Files

• LICENSE +30/−0
• Setup.hs +2/−0
• keera-hails-reactive-fs.cabal +61/−0
• src/Hails/FS.hs +45/−0

@@ -0,0 +1,30 @@+Copyright (c) 2015, Ivan Perez++All rights reserved.++Redistribution and use in source and binary forms, with or without+modification, are permitted provided that the following conditions are met:++    * Redistributions of source code must retain the above copyright+      notice, this list of conditions and the following disclaimer.++    * Redistributions in binary form must reproduce the above+      copyright notice, this list of conditions and the following+      disclaimer in the documentation and/or other materials provided+      with the distribution.++    * Neither the name of Ivan Perez nor the names of other+      contributors may be used to endorse or promote products derived+      from this software without specific prior written permission.++THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

@@ -0,0 +1,2 @@+import Distribution.Simple+main = defaultMain

@@ -0,0 +1,61 @@+-- hails.cabal auto-generated by cabal init. For additional options,+-- see+-- http://www.haskell.org/cabal/release/cabal-latest/doc/users-guide/authors.html#pkg-descr.+-- The name of the package.+Name:                keera-hails-reactive-fs++-- The package version. See the Haskell package versioning policy+-- (http://www.haskell.org/haskellwiki/Package_versioning_policy) for+-- standards guiding when and how versions should be incremented.+Version:             0.0.3.3++-- A short (one-line) description of the package.+Synopsis:            Haskell on Rails - Files as Reactive Values++-- A longer description of the package.+-- Description:         ++-- URL for the project homepage or repository.+Homepage:            http://www.keera.es/blog/community/++-- The license under which the package is released.+License:             BSD3++-- The file containing the license text.+License-file:        LICENSE++-- The package author(s).+Author:              Ivan Perez++-- An email address to which users can send suggestions, bug reports,+-- and patches.+Maintainer:          ivan.perez@keera.es++-- A copyright notice.+-- Copyright:           ++Category:            Development++Build-type:          Simple++-- Extra files to be distributed with the package, such as examples or+-- a README.+-- Extra-source-files:  ++-- Constraint on the version of Cabal needed to build this package.+Cabal-version:       >=1.2++Library+  hs-source-dirs: src/+  +  ghc-options: -Wall -fno-warn-unused-do-bind -O2++  -- Modules exported by the library.+  Exposed-modules: Hails.FS+  +  -- Packages needed in order to build this package.+  Build-depends: base >= 4 && < 5+               , directory+               , fsnotify+               , keera-hails-reactivevalues+               , system-filepath

@@ -0,0 +1,45 @@+{-# LANGUAGE UndecidableInstances #-}+{-# LANGUAGE FlexibleInstances    #-}+{-# LANGUAGE OverloadedStrings    #-}+module Hails.FS where++import Prelude hiding (FilePath)+import Control.Concurrent.MVar+import Control.Concurrent (threadDelay, forkIO)+import Control.Monad (forever)+import Data.ReactiveValue+import Filesystem.Path.CurrentOS+import System.Directory+import System.FSNotify++-- A file as a passive reactive value. Passive values are those+-- that never notify of changes to them. They are useful as+-- sources of information controlled by other RVs (buttons, etc.)+pasiveFileReactive :: FilePath -> ReactiveFieldReadWrite IO String+pasiveFileReactive fp = ReactiveFieldReadWrite setter getter notifier+ where getter     = readFile  (encodeString fp)+       setter v   = writeFile (encodeString fp) v+       notifier _ = return ()++-- | A file as a reactive value. The file must exist at the time+-- the call is evaluated.+--+-- TODO: Make it ok for the file not to exist.+-- TODO: Capture and ignore exceptions in readFile and writeFile.+fileReactive :: FilePath -> IO (ReactiveFieldReadWrite IO String)+fileReactive fp = do +  fpP <- canonicalizePath (encodeString fp)+  notifiers <- newMVar []+  let getter     = readFile  (encodeString fp)   -- fails if the path does not exist+      setter v   = writeFile (encodeString fp) v -- may fail+      notify     = sequence_ =<< readMVar notifiers+      notifier p = modifyMVar_ notifiers (\x -> return (x ++ [p]))++  -- Run the notification manager, ignore result (thread)+  forkIO $ withManager $ \mgr -> do+    _ <- watchDir mgr                                       -- manager+                  (directory fp)                            -- directory to watch+                  (\e -> encodeString (eventPath e) == fpP) -- predicate+                  (const notify)                            -- notifier+    forever $ threadDelay maxBound+  return $ ReactiveFieldReadWrite setter getter notifier