Merge pull request #177 from stoltene2/master

Adding a watch command

3 files changed, 85 insertions, 15 deletions

diff --git a/hakyll.cabal b/hakyll.cabal
index b23763a..0e570a7 100644
--- a/hakyll.cabal
+++ b/hakyll.cabal
@@ -78,6 +78,10 @@ Flag previewServer
   Description: Include the preview server
   Default:     True
 
+Flag watchServer
+  Description: Include the watch server
+  Default:     True
+
 Flag checkExternal
   Description: Include external link checking
   Default:     True
@@ -177,6 +181,15 @@ Library
       Hakyll.Preview.Poll
       Hakyll.Preview.Server
 
+  If flag(watchServer)
+    Build-depends:
+      fsnotify        >= 0.0.6 && < 0.1,
+      system-filepath >= 0.4.6 && <= 0.5
+    Cpp-options:
+      -DWATCH_SERVER
+    Other-modules:
+      Hakyll.Preview.Poll
+
   If flag(checkExternal)
     Build-depends:
       http-conduit >= 1.8    && < 1.10,
@@ -254,6 +267,15 @@ Test-suite hakyll-tests
       Hakyll.Preview.Poll
       Hakyll.Preview.Server
 
+  If flag(watchServer)
+    Build-depends:
+      fsnotify        >= 0.0.6 && < 0.1,
+      system-filepath >= 0.4.6 && <= 0.5
+    Cpp-options:
+      -DWATCH_SERVER
+    Other-modules:
+      Hakyll.Preview.Poll
+
   If flag(checkExternal)
     Build-depends:
       http-conduit >= 1.8    && < 1.10,
diff --git a/src/Hakyll/Commands.hs b/src/Hakyll/Commands.hs
index d86fd5c..7951f4e 100644
--- a/src/Hakyll/Commands.hs
+++ b/src/Hakyll/Commands.hs
@@ -1,4 +1,4 @@
---------------------------------------------------------------------------------
+ --------------------------------------------------------------------------------
 -- | Implementation of Hakyll commands: build, preview...
 {-# LANGUAGE CPP #-}
 module Hakyll.Commands
@@ -9,12 +9,14 @@ module Hakyll.Commands
     , rebuild
     , server
     , deploy
+    , watch 
     ) where
 
 
 --------------------------------------------------------------------------------
 import           System.Exit                (exitWith, ExitCode)
 import           Control.Applicative
+import           Control.Concurrent
 
 --------------------------------------------------------------------------------
 import qualified Hakyll.Check               as Check
@@ -26,8 +28,11 @@ import           Hakyll.Core.Runtime
 import           Hakyll.Core.Util.File
 
 --------------------------------------------------------------------------------
+#ifdef WATCH_SERVER
+import           Hakyll.Preview.Poll (watchUpdates)
+#endif
+
 #ifdef PREVIEW_SERVER
-import           Hakyll.Preview.Poll
 import           Hakyll.Preview.Server
 #endif
 
@@ -60,18 +65,39 @@ clean conf = do
 -- | Preview the site
 preview :: Configuration -> Verbosity -> Rules a -> Int -> IO ()
 #ifdef PREVIEW_SERVER
-preview conf verbosity rules port = do
+preview conf verbosity rules port  = do
+    deprecatedMessage
+    watch conf verbosity port True rules
+  where
+    deprecatedMessage = mapM_ putStrLn [ "The preview command has been deprecated."
+                                       , "Use the watch command for recompilation and serving."
+                                       ]
+#else
+preview _ _ _ _ = previewServerDisabled
+#endif
+
+
+--------------------------------------------------------------------------------
+-- | Watch and recompile for changes
+
+watch :: Configuration -> Verbosity -> Int -> Bool -> Rules a -> IO ()
+#ifdef WATCH_SERVER
+watch conf verbosity port runServer rules = do
     watchUpdates conf update
-    server conf port
+    _ <- forkIO (server')
+    loop
   where
     update = do
         (_, ruleSet) <- run conf verbosity rules
         return $ rulesPattern ruleSet
+
+    loop = threadDelay 100000 >> loop
+
+    server' = if runServer then server conf port else return ()
 #else
-preview _ _ _ _ = previewServerDisabled
+watch _ _ _ _ _ = watchServerDisabled
 #endif
 
-
 --------------------------------------------------------------------------------
 -- | Rebuild the site
 rebuild :: Configuration -> Verbosity -> Rules a -> IO ExitCode
@@ -111,3 +137,16 @@ previewServerDisabled =
         , "Alternatively, use an external tool to serve your site directory."
         ]
 #endif
+
+#ifndef WATCH_SERVER
+watchServerDisabled :: IO ()
+watchServerDisabled =
+    mapM_ putStrLn
+      [ "WATCH SERVER"
+      , ""
+      , "The watch server is not enabled in the version of Hakyll. To"
+      , "enable it, set the flag to True and recompile Hakyll."
+      , "Alternatively, use an external tool to serve your site directory."
+      ]
+#endif
+
diff --git a/src/Hakyll/Main.hs b/src/Hakyll/Main.hs
index 7e50418..4b30939 100644
--- a/src/Hakyll/Main.hs
+++ b/src/Hakyll/Main.hs
@@ -41,14 +41,15 @@ hakyllWith conf rules = do
             if internal_links args' then Check.InternalLinks else Check.All
 
     case args' of
-        Build   _   -> Commands.build conf verbosity' rules >>= exitWith
-        Check   _ _ -> Commands.check conf verbosity' check'
-        Clean   _   -> Commands.clean conf
-        Deploy  _   -> Commands.deploy conf >>= exitWith
-        Help    _   -> showHelp
-        Preview _ p -> Commands.preview conf verbosity' rules p
-        Rebuild _   -> Commands.rebuild conf verbosity' rules >>= exitWith
-        Server  _ _ -> Commands.server conf (port args')
+        Build   _     -> Commands.build conf verbosity' rules >>= exitWith
+        Check   _ _   -> Commands.check conf verbosity' check'
+        Clean   _     -> Commands.clean conf
+        Deploy  _     -> Commands.deploy conf >>= exitWith
+        Help    _     -> showHelp
+        Preview _ p   -> Commands.preview conf verbosity' rules p
+        Rebuild _     -> Commands.rebuild conf verbosity' rules >>= exitWith
+        Server  _ _   -> Commands.server conf (port args')
+        Watch   _ p s -> Commands.watch conf verbosity' p (not s) rules
 
 
 --------------------------------------------------------------------------------
@@ -67,6 +68,7 @@ data HakyllArgs
     | Preview {verbose :: Bool, port :: Int}
     | Rebuild {verbose :: Bool}
     | Server  {verbose :: Bool, port :: Int}
+    | Watch   {verbose :: Bool, port :: Int, no_server :: Bool }
     deriving (Data, Typeable, Show)
 
 
@@ -80,10 +82,12 @@ hakyllArgs = modes
     , (Deploy $ verboseFlag def) &= help "Upload/deploy your site"
     , (Help $ verboseFlag def) &= help "Show this message" &= auto
     , (Preview (verboseFlag def) (portFlag 8000)) &=
-        help "Start a preview server and autocompile on changes"
+        help "[Deprecated] Please use the watch command"
     , (Rebuild $ verboseFlag def) &= help "Clean and build again"
     , (Server (verboseFlag def) (portFlag 8000)) &=
         help "Start a preview server"
+    , (Watch (verboseFlag def) (portFlag 8000) (noServerFlag False) &=
+       help "Autocompile on changes and start a preview server.  You can watch and recompile without running a server with --no-server.")
     ] &= help "Hakyll static site compiler" &= program progName
 
 
@@ -94,6 +98,11 @@ verboseFlag x = x &= help "Run in verbose mode"
 
 
 --------------------------------------------------------------------------------
+noServerFlag :: Data a => a -> a
+noServerFlag x = x &= help "Disable the built-in web server"
+{-# INLINE noServerFlag #-}
+
+--------------------------------------------------------------------------------
 portFlag :: Data a => a -> a
 portFlag x = x &= help "Port to listen on"
 {-# INLINE portFlag #-}