CodyReichert · August 29, 2015 14:08 · Nov 29, 2014 · Nov 6, 2014
diff --git a/DevelMain.hs b/DevelMain.hs
@@ -1,13 +1,11 @@
--- | Development version to be run inside GHCi.
+-- Development version to be run inside GHCi.
 --
 -- Modified DevelMain.hs to reload Chrome browser tabs on recompile
 -- 
 -- start this up with:
---
 -- cabal repl --ghc-options="-O0 -fobject-code"
---o
--- run with:
 --
+-- run with:
 -- :l DevelMain
 -- DevelMain.update
 --

diff --git a/DevelMain.hs b/DevelMain.hs
@@ -0,0 +1,75 @@
+-- | Development version to be run inside GHCi.
+--
+-- Modified DevelMain.hs to reload Chrome browser tabs on recompile
+-- 
+-- start this up with:
+--
+-- cabal repl --ghc-options="-O0 -fobject-code"
+--o
+-- run with:
+--
+-- :l DevelMain
+-- DevelMain.update
+--
+-- You will need to add these packages to your .cabal file
+-- * foreign-store >= 0.1 (very light-weight)
+-- * warp (you already depend on this, it just isn't in your .cabal file)
+--
+-- If you don't use cabal repl, you will need
+-- to add settings to your .ghci file.
+--
+-- :set -DDEVELOPMENT
+--
+-- There is more information about using ghci
+-- on the wiki: https://github.com/yesodweb/yesod/wiki/ghci
+
+module DevelMain where
+
+import Application (getApplicationDev)
+
+import Control.Exception (finally)
+import Control.Concurrent
+import Data.IORef
+import Foreign.Store
+import Network.Wai.Handler.Warp
+import Prelude
+import System.Process
+
+-- | Start or restart the server.
+-- A Store holds onto some data across ghci reloads
+update :: IO ()
+update = do
+    mtidStore <- lookupStore tidStoreNum
+    case mtidStore of
+      -- no server running
+      Nothing -> do
+          done <- storeAction doneStore newEmptyMVar
+          tid <- start done
+          _ <- storeAction (Store tidStoreNum) (newIORef tid)
+          return ()
+      -- server is already running
+      Just tidStore ->
+          -- shut the server down with killThread and wait for the done signal
+          modifyStoredIORef tidStore $ \tid -> do
+              killThread tid
+              withStore doneStore takeMVar >> readStore doneStore >>= start
+    rawSystem "chromix" ["with", "localhost:3000", "reloadWithoutCache"]
+    return ()
+
+  where
+    doneStore = Store 0
+    tidStoreNum = 1
+
+    modifyStoredIORef :: Store (IORef a) -> (a -> IO a) -> IO ()
+    modifyStoredIORef store f = withStore store $ \ref -> do
+        v <- readIORef ref
+        f v >>= writeIORef ref
+
+-- | Start the server in a separate thread.
+start :: MVar () -- ^ Written to when the thread is killed.
+      -> IO ThreadId
+start done = do
+    (port,app) <- getApplicationDev
+    forkIO $ system "chromix-server" >> return ()
+    forkIO (finally (runSettings (setPort port defaultSettings) app)
+                    (putMVar done ()))