Scaffolding update

yesod-bin/ChangeLog.md

@@ -1,3 +1,11 @@
+## 1.4.3.4
+
+Scaffolding updates:
+
+* Improve `DevelMain` support
+* Wipe out database during test runs
+* Convenience `unsafeHandler` function
+
 ## 1.4.3.3
 
 More consistent whitespace in hamlet files in scaffolding [#50](https://github.com/yesodweb/yesod-scaffold/issues/50)

yesod-bin/hsfiles/mongo.hsfiles

@@ -32,15 +32,22 @@ module Application
     , appMain
     , develMain
     , makeFoundation
+    -- * for DevelMain
+    , getApplicationRepl
+    , shutdownApp
+    -- * for GHCI
+    , handler
+    , db
     ) where
 
 import Control.Monad.Logger                 (liftLoc)
+import Database.Persist.MongoDB             (MongoContext)
 import Import
 import Language.Haskell.TH.Syntax           (qLocation)
 import Network.Wai.Handler.Warp             (Settings, defaultSettings,
                                              defaultShouldDisplayException,
                                              runSettings, setHost,
-                                             setOnException, setPort)
+                                             setOnException, setPort, getPort)
 import Network.Wai.Middleware.RequestLogger (Destination (Logger),
                                              IPAddrSource (..),
                                              OutputFormat (..), destination,
@@ -115,12 +122,15 @@ warpSettings foundation =
 -- | For yesod devel, return the Warp settings and WAI Application.
 getApplicationDev :: IO (Settings, Application)
 getApplicationDev = do
-    settings <- loadAppSettings [configSettingsYml] [] useEnv
+    settings <- getAppSettings
     foundation <- makeFoundation settings
-    app <- makeApplication foundation
     wsettings <- getDevSettings $ warpSettings foundation
+    app <- makeApplication foundation
     return (wsettings, app)
 
+getAppSettings :: IO AppSettings
+getAppSettings = loadAppSettings [configSettingsYml] [] useEnv
+
 -- | main function for use by yesod devel
 develMain :: IO ()
 develMain = develMainHelper getApplicationDev
@@ -145,16 +155,45 @@ appMain = do
     -- Run the application with Warp
     runSettings (warpSettings foundation) app
 
+
+--------------------------------------------------------------
+-- Functions for DevelMain.hs (a way to run the app from GHCi)
+--------------------------------------------------------------
+getApplicationRepl :: IO (Int, App, Application)
+getApplicationRepl = do
+    settings <- getAppSettings
+    foundation <- makeFoundation settings
+    wsettings <- getDevSettings $ warpSettings foundation
+    app1 <- makeApplication foundation
+    return (getPort wsettings, foundation, app1)
+
+shutdownApp :: App -> IO ()
+shutdownApp _ = return ()
+
+
+---------------------------------------------
+-- Functions for use in development with GHCi
+---------------------------------------------
+
+-- | Run a handler
+handler :: Handler a -> IO a
+handler h = getAppSettings >>= makeFoundation >>= flip unsafeHandler h
+
+-- | Run DB queries
+db :: ReaderT MongoContext (HandlerT App IO) a -> IO a
+db = handler . runDB
+
 {-# START_FILE Foundation.hs #-}
 module Foundation where
 
 import Database.Persist.MongoDB hiding (master)
 import Import.NoFoundation
-import Text.Hamlet              (hamletFile)
+import Text.Hamlet                 (hamletFile)
-import Text.Jasmine             (minifym)
+import Text.Jasmine                (minifym)
-import Yesod.Auth.BrowserId     (authBrowserId)
+import Yesod.Auth.BrowserId        (authBrowserId)
-import Yesod.Core.Types         (Logger)
+import Yesod.Core.Types            (Logger)
-import Yesod.Default.Util       (addStaticContentExternal)
+import Yesod.Default.Util          (addStaticContentExternal)
+import qualified Yesod.Core.Unsafe as Unsafe
 
 -- | The foundation datatype for your application. This can be a good place to
 -- keep settings and values requiring initialization before your application
@@ -291,6 +330,9 @@ instance YesodAuthPersist App
 instance RenderMessage App FormMessage where
     renderMessage _ _ = defaultFormMessage
 
+unsafeHandler :: App -> Handler a -> IO a
+unsafeHandler = Unsafe.fakeHandlerGetLogger appLogger
+
 -- Note: Some functionality previously present in the scaffolding has been
 -- moved to documentation in the Wiki. Following are some hopefully helpful
 -- links:
@@ -411,6 +453,7 @@ Flag library-only
     Default:       False
 
 library
+    hs-source-dirs: ., app
     exposed-modules: Application
                      Foundation
                      Import
@@ -446,7 +489,7 @@ library
 
     build-depends: base                          >= 4          && < 5
                  , yesod                         >= 1.4.1      && < 1.5
-                 , yesod-core                    >= 1.4.0      && < 1.5
+                 , yesod-core                    >= 1.4.6      && < 1.5
                  , yesod-auth                    >= 1.4.0      && < 1.5
                  , yesod-static                  >= 1.4.0.3    && < 1.5
                  , yesod-form                    >= 1.4.0      && < 1.5
@@ -683,40 +726,51 @@ import Yesod.Static (staticFiles)
 staticFiles (appStaticDir compileTimeAppSettings)
 
 {-# START_FILE app/DevelMain.hs #-}
--- | Development version to be run inside GHCi.
+-- | Running your app inside GHCi.
 --
--- start this up with:
+-- To start up GHCi for usage with Yesod, first make sure you are in dev mode:
 --
--- cabal repl --ghc-options="-O0 -fobject-code"
+-- > cabal configure -fdev
 --
--- run with:
+-- Note that @yesod devel@ automatically sets the dev flag.
+-- Now launch the repl:
 --
--- :l DevelMain
+-- > cabal repl --ghc-options="-O0 -fobject-code"
--- DevelMain.update
 --
--- You will need to add these packages to your .cabal file
+-- To start your app, run:
--- * foreign-store >= 0.1 (very light-weight)
+--
--- * warp (you already depend on this, it just isn't in your .cabal file)
+-- > :l DevelMain
+-- > DevelMain.update
+--
+-- You can also call @DevelMain.shutdown@ to stop the app
+--
+-- You will need to add the foreign-store package to your .cabal file.
+-- It is very light-weight.
 --
 -- If you don't use cabal repl, you will need
--- to add settings to your .ghci file.
+-- to run the following in GHCi or to add it to
+-- your .ghci file.
 --
 -- :set -DDEVELOPMENT
 --
--- There is more information about using ghci
+-- There is more information about this approach,
 -- on the wiki: https://github.com/yesodweb/yesod/wiki/ghci
 
 module DevelMain where
 
-import Application (getApplicationDev)
+import Prelude
+import Application (getApplicationRepl, shutdownApp)
 
 import Control.Exception (finally)
+import Control.Monad ((>=>))
 import Control.Concurrent
 import Data.IORef
 import Foreign.Store
 import Network.Wai.Handler.Warp
+import GHC.Word
 
 -- | Start or restart the server.
+-- newStore is from foreign-store.
 -- A Store holds onto some data across ghci reloads
 update :: IO ()
 update = do
@@ -729,27 +783,48 @@ update = do
           _ <- storeAction (Store tidStoreNum) (newIORef tid)
           return ()
       -- server is already running
-      Just tidStore ->
+      Just tidStore -> restartAppInNewThread 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
   where
+    doneStore :: Store (MVar ())
     doneStore = Store 0
-    tidStoreNum = 1
 
-    modifyStoredIORef :: Store (IORef a) -> (a -> IO a) -> IO ()
+    -- shut the server down with killThread and wait for the done signal
-    modifyStoredIORef store f = withStore store $ \ref -> do
+    restartAppInNewThread :: Store (IORef ThreadId) -> IO ()
-        v <- readIORef ref
+    restartAppInNewThread tidStore = modifyStoredIORef tidStore $ \tid -> do
-        f v >>= writeIORef ref
+        killThread tid
+        withStore doneStore takeMVar
+        readStore doneStore >>= start
 
--- | Start the server in a separate thread.
+
-start :: MVar () -- ^ Written to when the thread is killed.
+    -- | Start the server in a separate thread.
-      -> IO ThreadId
+    start :: MVar () -- ^ Written to when the thread is killed.
-start done = do
+          -> IO ThreadId
-    (settings,app) <- getApplicationDev
+    start done = do
-    forkIO (finally (runSettings settings app)
+        (port, site, app) <- getApplicationRepl
-                    (putMVar done ()))
+        forkIO (finally (runSettings (setPort port defaultSettings) app)
+                        -- Note that this implies concurrency
+                        -- between shutdownApp and the next app that is starting.
+                        -- Normally this should be fine
+                        (putMVar done () >> shutdownApp site))
+
+-- | kill the server
+shutdown :: IO ()
+shutdown = do
+    mtidStore <- lookupStore tidStoreNum
+    case mtidStore of
+      -- no server running
+      Nothing -> putStrLn "no Yesod app running"
+      Just tidStore -> do
+          withStore tidStore $ readIORef >=> killThread
+          putStrLn "Yesod app is shutdown"
+
+tidStoreNum :: Word32
+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_FILE app/devel.hs #-}
 {-# LANGUAGE PackageImports #-}

yesod-bin/hsfiles/mysql.hsfiles

@@ -32,6 +32,12 @@ module Application
     , appMain
     , develMain
     , makeFoundation
+    -- * for DevelMain
+    , getApplicationRepl
+    , shutdownApp
+    -- * for GHCI
+    , handler
+    , db
     ) where
 
 import Control.Monad.Logger                 (liftLoc, runLoggingT)
@@ -42,7 +48,7 @@ import Language.Haskell.TH.Syntax           (qLocation)
 import Network.Wai.Handler.Warp             (Settings, defaultSettings,
                                              defaultShouldDisplayException,
                                              runSettings, setHost,
-                                             setOnException, setPort)
+                                             setOnException, setPort, getPort)
 import Network.Wai.Middleware.RequestLogger (Destination (Logger),
                                              IPAddrSource (..),
                                              OutputFormat (..), destination,
@@ -131,12 +137,15 @@ warpSettings foundation =
 -- | For yesod devel, return the Warp settings and WAI Application.
 getApplicationDev :: IO (Settings, Application)
 getApplicationDev = do
-    settings <- loadAppSettings [configSettingsYml] [] useEnv
+    settings <- getAppSettings
     foundation <- makeFoundation settings
-    app <- makeApplication foundation
     wsettings <- getDevSettings $ warpSettings foundation
+    app <- makeApplication foundation
     return (wsettings, app)
 
+getAppSettings :: IO AppSettings
+getAppSettings = loadAppSettings [configSettingsYml] [] useEnv
+
 -- | main function for use by yesod devel
 develMain :: IO ()
 develMain = develMainHelper getApplicationDev
@@ -161,6 +170,34 @@ appMain = do
     -- Run the application with Warp
     runSettings (warpSettings foundation) app
 
+
+--------------------------------------------------------------
+-- Functions for DevelMain.hs (a way to run the app from GHCi)
+--------------------------------------------------------------
+getApplicationRepl :: IO (Int, App, Application)
+getApplicationRepl = do
+    settings <- getAppSettings
+    foundation <- makeFoundation settings
+    wsettings <- getDevSettings $ warpSettings foundation
+    app1 <- makeApplication foundation
+    return (getPort wsettings, foundation, app1)
+
+shutdownApp :: App -> IO ()
+shutdownApp _ = return ()
+
+
+---------------------------------------------
+-- Functions for use in development with GHCi
+---------------------------------------------
+
+-- | Run a handler
+handler :: Handler a -> IO a
+handler h = getAppSettings >>= makeFoundation >>= flip unsafeHandler h
+
+-- | Run DB queries
+db :: ReaderT SqlBackend (HandlerT App IO) a -> IO a
+db = handler . runDB
+
 {-# START_FILE Foundation.hs #-}
 module Foundation where
 
@@ -171,6 +208,7 @@ import Text.Jasmine         (minifym)
 import Yesod.Auth.BrowserId (authBrowserId)
 import Yesod.Default.Util   (addStaticContentExternal)
 import Yesod.Core.Types     (Logger)
+import qualified Yesod.Core.Unsafe as Unsafe
 
 -- | The foundation datatype for your application. This can be a good place to
 -- keep settings and values requiring initialization before your application
@@ -306,6 +344,9 @@ instance YesodAuthPersist App
 instance RenderMessage App FormMessage where
     renderMessage _ _ = defaultFormMessage
 
+unsafeHandler :: App -> Handler a -> IO a
+unsafeHandler = Unsafe.fakeHandlerGetLogger appLogger
+
 -- Note: Some functionality previously present in the scaffolding has been
 -- moved to documentation in the Wiki. Following are some hopefully helpful
 -- links:
@@ -423,6 +464,7 @@ Flag library-only
     Default:       False
 
 library
+    hs-source-dirs: ., app
     exposed-modules: Application
                      Foundation
                      Import
@@ -458,7 +500,7 @@ library
 
     build-depends: base                          >= 4          && < 5
                  , yesod                         >= 1.4.1      && < 1.5
-                 , yesod-core                    >= 1.4.0      && < 1.5
+                 , yesod-core                    >= 1.4.6      && < 1.5
                  , yesod-auth                    >= 1.4.0      && < 1.5
                  , yesod-static                  >= 1.4.0.3    && < 1.5
                  , yesod-form                    >= 1.4.0      && < 1.5
@@ -695,40 +737,51 @@ import Yesod.Static (staticFiles)
 staticFiles (appStaticDir compileTimeAppSettings)
 
 {-# START_FILE app/DevelMain.hs #-}
--- | Development version to be run inside GHCi.
+-- | Running your app inside GHCi.
 --
--- start this up with:
+-- To start up GHCi for usage with Yesod, first make sure you are in dev mode:
 --
--- cabal repl --ghc-options="-O0 -fobject-code"
+-- > cabal configure -fdev
 --
--- run with:
+-- Note that @yesod devel@ automatically sets the dev flag.
+-- Now launch the repl:
 --
--- :l DevelMain
+-- > cabal repl --ghc-options="-O0 -fobject-code"
--- DevelMain.update
 --
--- You will need to add these packages to your .cabal file
+-- To start your app, run:
--- * foreign-store >= 0.1 (very light-weight)
+--
--- * warp (you already depend on this, it just isn't in your .cabal file)
+-- > :l DevelMain
+-- > DevelMain.update
+--
+-- You can also call @DevelMain.shutdown@ to stop the app
+--
+-- You will need to add the foreign-store package to your .cabal file.
+-- It is very light-weight.
 --
 -- If you don't use cabal repl, you will need
--- to add settings to your .ghci file.
+-- to run the following in GHCi or to add it to
+-- your .ghci file.
 --
 -- :set -DDEVELOPMENT
 --
--- There is more information about using ghci
+-- There is more information about this approach,
 -- on the wiki: https://github.com/yesodweb/yesod/wiki/ghci
 
 module DevelMain where
 
-import Application (getApplicationDev)
+import Prelude
+import Application (getApplicationRepl, shutdownApp)
 
 import Control.Exception (finally)
+import Control.Monad ((>=>))
 import Control.Concurrent
 import Data.IORef
 import Foreign.Store
 import Network.Wai.Handler.Warp
+import GHC.Word
 
 -- | Start or restart the server.
+-- newStore is from foreign-store.
 -- A Store holds onto some data across ghci reloads
 update :: IO ()
 update = do
@@ -741,27 +794,48 @@ update = do
           _ <- storeAction (Store tidStoreNum) (newIORef tid)
           return ()
       -- server is already running
-      Just tidStore ->
+      Just tidStore -> restartAppInNewThread 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
   where
+    doneStore :: Store (MVar ())
     doneStore = Store 0
-    tidStoreNum = 1
 
-    modifyStoredIORef :: Store (IORef a) -> (a -> IO a) -> IO ()
+    -- shut the server down with killThread and wait for the done signal
-    modifyStoredIORef store f = withStore store $ \ref -> do
+    restartAppInNewThread :: Store (IORef ThreadId) -> IO ()
-        v <- readIORef ref
+    restartAppInNewThread tidStore = modifyStoredIORef tidStore $ \tid -> do
-        f v >>= writeIORef ref
+        killThread tid
+        withStore doneStore takeMVar
+        readStore doneStore >>= start
 
--- | Start the server in a separate thread.
+
-start :: MVar () -- ^ Written to when the thread is killed.
+    -- | Start the server in a separate thread.
-      -> IO ThreadId
+    start :: MVar () -- ^ Written to when the thread is killed.
-start done = do
+          -> IO ThreadId
-    (settings,app) <- getApplicationDev
+    start done = do
-    forkIO (finally (runSettings settings app)
+        (port, site, app) <- getApplicationRepl
-                    (putMVar done ()))
+        forkIO (finally (runSettings (setPort port defaultSettings) app)
+                        -- Note that this implies concurrency
+                        -- between shutdownApp and the next app that is starting.
+                        -- Normally this should be fine
+                        (putMVar done () >> shutdownApp site))
+
+-- | kill the server
+shutdown :: IO ()
+shutdown = do
+    mtidStore <- lookupStore tidStoreNum
+    case mtidStore of
+      -- no server running
+      Nothing -> putStrLn "no Yesod app running"
+      Just tidStore -> do
+          withStore tidStore $ readIORef >=> killThread
+          putStrLn "Yesod app is shutdown"
+
+tidStoreNum :: Word32
+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_FILE app/devel.hs #-}
 {-# LANGUAGE PackageImports #-}
@@ -9032,7 +9106,7 @@ module TestImport
 import Application           (makeFoundation)
 import ClassyPrelude         as X
 import Database.Persist      as X hiding (get)
-import Database.Persist.Sql  (SqlPersistM, runSqlPersistMPool)
+import Database.Persist.Sql  (SqlPersistM, SqlBackend, runSqlPersistMPool, rawExecute, rawSql, unSingle, connEscapeName)
 import Foundation            as X
 import Model                 as X
 import Test.Hspec            as X
@@ -9041,8 +9115,11 @@ import Yesod.Test            as X
 
 runDB :: SqlPersistM a -> YesodExample App a
 runDB query = do
-    pool <- fmap appConnPool getTestYesod
+    app <- getTestYesod
-    liftIO $ runSqlPersistMPool query pool
+    liftIO $ runDBWithApp app query
+
+runDBWithApp :: App -> SqlPersistM a -> IO a
+runDBWithApp app query = runSqlPersistMPool query (appConnPool app)
 
 withApp :: SpecWith App -> Spec
 withApp = before $ do
@@ -9050,5 +9127,30 @@ withApp = before $ do
         ["config/test-settings.yml", "config/settings.yml"]
         []
         ignoreEnv
-    makeFoundation settings
+    foundation <- makeFoundation settings
+    wipeDB foundation
+    return foundation
+
+-- This function will truncate all of the tables in your database.
+-- 'withApp' calls it before each test, creating a clean environment for each
+-- spec to run in.
+wipeDB :: App -> IO ()
+wipeDB app = do
+    runDBWithApp app $ do
+        tables <- getTables
+        sqlBackend <- ask
+        let queries = map (\t -> "TRUNCATE TABLE " ++ (connEscapeName sqlBackend $ DBName t)) tables
+
+        -- In MySQL, a table cannot be truncated if another table references it via foreign key.
+        -- Since we're wiping both the parent and child tables, though, it's safe
+        -- to temporarily disable this check.
+        rawExecute "SET foreign_key_checks = 0;" []
+        forM_ queries (\q -> rawExecute q [])
+        rawExecute "SET foreign_key_checks = 1;" []
+    return ()
+
+getTables :: MonadIO m => ReaderT SqlBackend m [Text]
+getTables = do
+    tables <- rawSql "SHOW TABLES;" []
+    return $ map unSingle tables
 

yesod-bin/hsfiles/postgres-fay.hsfiles

@@ -35,6 +35,12 @@ module Application
     , appMain
     , develMain
     , makeFoundation
+    -- * for DevelMain
+    , getApplicationRepl
+    , shutdownApp
+    -- * for GHCI
+    , handler
+    , db
     ) where
 
 import Control.Monad.Logger                 (liftLoc, runLoggingT)
@@ -45,7 +51,7 @@ import Language.Haskell.TH.Syntax           (qLocation)
 import Network.Wai.Handler.Warp             (Settings, defaultSettings,
                                              defaultShouldDisplayException,
                                              runSettings, setHost,
-                                             setOnException, setPort)
+                                             setOnException, setPort, getPort)
 import Network.Wai.Middleware.RequestLogger (Destination (Logger),
                                              IPAddrSource (..),
                                              OutputFormat (..), destination,
@@ -137,12 +143,15 @@ warpSettings foundation =
 -- | For yesod devel, return the Warp settings and WAI Application.
 getApplicationDev :: IO (Settings, Application)
 getApplicationDev = do
-    settings <- loadAppSettings [configSettingsYml] [] useEnv
+    settings <- getAppSettings
     foundation <- makeFoundation settings
-    app <- makeApplication foundation
     wsettings <- getDevSettings $ warpSettings foundation
+    app <- makeApplication foundation
     return (wsettings, app)
 
+getAppSettings :: IO AppSettings
+getAppSettings = loadAppSettings [configSettingsYml] [] useEnv
+
 -- | main function for use by yesod devel
 develMain :: IO ()
 develMain = develMainHelper getApplicationDev
@@ -167,15 +176,44 @@ appMain = do
     -- Run the application with Warp
     runSettings (warpSettings foundation) app
 
+
+--------------------------------------------------------------
+-- Functions for DevelMain.hs (a way to run the app from GHCi)
+--------------------------------------------------------------
+getApplicationRepl :: IO (Int, App, Application)
+getApplicationRepl = do
+    settings <- getAppSettings
+    foundation <- makeFoundation settings
+    wsettings <- getDevSettings $ warpSettings foundation
+    app1 <- makeApplication foundation
+    return (getPort wsettings, foundation, app1)
+
+shutdownApp :: App -> IO ()
+shutdownApp _ = return ()
+
+
+---------------------------------------------
+-- Functions for use in development with GHCi
+---------------------------------------------
+
+-- | Run a handler
+handler :: Handler a -> IO a
+handler h = getAppSettings >>= makeFoundation >>= flip unsafeHandler h
+
+-- | Run DB queries
+db :: ReaderT SqlBackend (HandlerT App IO) a -> IO a
+db = handler . runDB
+
 {-# START_FILE Foundation.hs #-}
 module Foundation where
 
-import Database.Persist.Sql (ConnectionPool, runSqlPool)
+import Database.Persist.Sql        (ConnectionPool, runSqlPool)
 import Import.NoFoundation
-import Text.Hamlet          (hamletFile)
+import Text.Hamlet                 (hamletFile)
-import Yesod.Auth.BrowserId (authBrowserId)
+import Yesod.Auth.BrowserId        (authBrowserId)
-import Yesod.Core.Types     (Logger)
+import qualified Yesod.Core.Unsafe as Unsafe
-import Yesod.Default.Util   (addStaticContentExternal)
+import Yesod.Core.Types            (Logger)
+import Yesod.Default.Util          (addStaticContentExternal)
 import Yesod.Fay
 
 -- | The foundation datatype for your application. This can be a good place to
@@ -322,6 +360,9 @@ instance YesodAuthPersist App
 instance RenderMessage App FormMessage where
     renderMessage _ _ = defaultFormMessage
 
+unsafeHandler :: App -> Handler a -> IO a
+unsafeHandler = Unsafe.fakeHandlerGetLogger appLogger
+
 -- Note: Some functionality previously present in the scaffolding has been
 -- moved to documentation in the Wiki. Following are some hopefully helpful
 -- links:
@@ -463,7 +504,7 @@ Flag library-only
     Default:       False
 
 library
-    hs-source-dirs: ., fay-shared
+    hs-source-dirs: ., fay-shared, app
     exposed-modules: Application
                      Foundation
                      Import
@@ -502,7 +543,7 @@ library
 
     build-depends: base                          >= 4          && < 5
                  , yesod                         >= 1.4.1      && < 1.5
-                 , yesod-core                    >= 1.4.0      && < 1.5
+                 , yesod-core                    >= 1.4.6      && < 1.5
                  , yesod-auth                    >= 1.4.0      && < 1.5
                  , yesod-static                  >= 1.4.0.3    && < 1.5
                  , yesod-form                    >= 1.4.0      && < 1.5
@@ -755,40 +796,51 @@ import Yesod.Static (staticFiles)
 staticFiles (appStaticDir compileTimeAppSettings)
 
 {-# START_FILE app/DevelMain.hs #-}
--- | Development version to be run inside GHCi.
+-- | Running your app inside GHCi.
 --
--- start this up with:
+-- To start up GHCi for usage with Yesod, first make sure you are in dev mode:
 --
--- cabal repl --ghc-options="-O0 -fobject-code"
+-- > cabal configure -fdev
 --
--- run with:
+-- Note that @yesod devel@ automatically sets the dev flag.
+-- Now launch the repl:
 --
--- :l DevelMain
+-- > cabal repl --ghc-options="-O0 -fobject-code"
--- DevelMain.update
 --
--- You will need to add these packages to your .cabal file
+-- To start your app, run:
--- * foreign-store >= 0.1 (very light-weight)
+--
--- * warp (you already depend on this, it just isn't in your .cabal file)
+-- > :l DevelMain
+-- > DevelMain.update
+--
+-- You can also call @DevelMain.shutdown@ to stop the app
+--
+-- You will need to add the foreign-store package to your .cabal file.
+-- It is very light-weight.
 --
 -- If you don't use cabal repl, you will need
--- to add settings to your .ghci file.
+-- to run the following in GHCi or to add it to
+-- your .ghci file.
 --
 -- :set -DDEVELOPMENT
 --
--- There is more information about using ghci
+-- There is more information about this approach,
 -- on the wiki: https://github.com/yesodweb/yesod/wiki/ghci
 
 module DevelMain where
 
-import Application (getApplicationDev)
+import Prelude
+import Application (getApplicationRepl, shutdownApp)
 
 import Control.Exception (finally)
+import Control.Monad ((>=>))
 import Control.Concurrent
 import Data.IORef
 import Foreign.Store
 import Network.Wai.Handler.Warp
+import GHC.Word
 
 -- | Start or restart the server.
+-- newStore is from foreign-store.
 -- A Store holds onto some data across ghci reloads
 update :: IO ()
 update = do
@@ -801,27 +853,48 @@ update = do
           _ <- storeAction (Store tidStoreNum) (newIORef tid)
           return ()
       -- server is already running
-      Just tidStore ->
+      Just tidStore -> restartAppInNewThread 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
   where
+    doneStore :: Store (MVar ())
     doneStore = Store 0
-    tidStoreNum = 1
 
-    modifyStoredIORef :: Store (IORef a) -> (a -> IO a) -> IO ()
+    -- shut the server down with killThread and wait for the done signal
-    modifyStoredIORef store f = withStore store $ \ref -> do
+    restartAppInNewThread :: Store (IORef ThreadId) -> IO ()
-        v <- readIORef ref
+    restartAppInNewThread tidStore = modifyStoredIORef tidStore $ \tid -> do
-        f v >>= writeIORef ref
+        killThread tid
+        withStore doneStore takeMVar
+        readStore doneStore >>= start
 
--- | Start the server in a separate thread.
+
-start :: MVar () -- ^ Written to when the thread is killed.
+    -- | Start the server in a separate thread.
-      -> IO ThreadId
+    start :: MVar () -- ^ Written to when the thread is killed.
-start done = do
+          -> IO ThreadId
-    (settings,app) <- getApplicationDev
+    start done = do
-    forkIO (finally (runSettings settings app)
+        (port, site, app) <- getApplicationRepl
-                    (putMVar done ()))
+        forkIO (finally (runSettings (setPort port defaultSettings) app)
+                        -- Note that this implies concurrency
+                        -- between shutdownApp and the next app that is starting.
+                        -- Normally this should be fine
+                        (putMVar done () >> shutdownApp site))
+
+-- | kill the server
+shutdown :: IO ()
+shutdown = do
+    mtidStore <- lookupStore tidStoreNum
+    case mtidStore of
+      -- no server running
+      Nothing -> putStrLn "no Yesod app running"
+      Just tidStore -> do
+          withStore tidStore $ readIORef >=> killThread
+          putStrLn "Yesod app is shutdown"
+
+tidStoreNum :: Word32
+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_FILE app/devel.hs #-}
 {-# LANGUAGE PackageImports #-}
@@ -9153,7 +9226,7 @@ module TestImport
 import Application           (makeFoundation)
 import ClassyPrelude         as X
 import Database.Persist      as X hiding (get)
-import Database.Persist.Sql  (SqlPersistM, runSqlPersistMPool)
+import Database.Persist.Sql  (SqlPersistM, SqlBackend, runSqlPersistMPool, rawExecute, rawSql, unSingle, connEscapeName)
 import Foundation            as X
 import Model                 as X
 import Test.Hspec            as X
@@ -9162,8 +9235,12 @@ import Yesod.Test            as X
 
 runDB :: SqlPersistM a -> YesodExample App a
 runDB query = do
-    pool <- fmap appConnPool getTestYesod
+    app <- getTestYesod
-    liftIO $ runSqlPersistMPool query pool
+    liftIO $ runDBWithApp app query
+
+runDBWithApp :: App -> SqlPersistM a -> IO a
+runDBWithApp app query = runSqlPersistMPool query (appConnPool app)
+
 
 withApp :: SpecWith App -> Spec
 withApp = before $ do
@@ -9171,5 +9248,24 @@ withApp = before $ do
         ["config/test-settings.yml", "config/settings.yml"]
         []
         ignoreEnv
-    makeFoundation settings
+    foundation <- makeFoundation settings
+    wipeDB foundation
+    return foundation
 
+-- This function will truncate all of the tables in your database.
+-- 'withApp' calls it before each test, creating a clean environment for each
+-- spec to run in.
+wipeDB :: App -> IO ()
+wipeDB app = do
+    runDBWithApp app $ do
+        tables <- getTables
+        sqlBackend <- ask
+
+        let escapedTables = map (connEscapeName sqlBackend . DBName) tables
+            query = "TRUNCATE TABLE " ++ (intercalate ", " escapedTables)
+        rawExecute query []
+
+getTables :: MonadIO m => ReaderT SqlBackend m [Text]
+getTables = do
+    tables <- rawSql "SELECT table_name FROM information_schema.tables WHERE table_schema = 'public';" []
+    return $ map unSingle tables

yesod-bin/hsfiles/postgres.hsfiles

@@ -32,6 +32,12 @@ module Application
     , appMain
     , develMain
     , makeFoundation
+    -- * for DevelMain
+    , getApplicationRepl
+    , shutdownApp
+    -- * for GHCI
+    , handler
+    , db
     ) where
 
 import Control.Monad.Logger                 (liftLoc, runLoggingT)
@@ -42,7 +48,7 @@ import Language.Haskell.TH.Syntax           (qLocation)
 import Network.Wai.Handler.Warp             (Settings, defaultSettings,
                                              defaultShouldDisplayException,
                                              runSettings, setHost,
-                                             setOnException, setPort)
+                                             setOnException, setPort, getPort)
 import Network.Wai.Middleware.RequestLogger (Destination (Logger),
                                              IPAddrSource (..),
                                              OutputFormat (..), destination,
@@ -131,12 +137,15 @@ warpSettings foundation =
 -- | For yesod devel, return the Warp settings and WAI Application.
 getApplicationDev :: IO (Settings, Application)
 getApplicationDev = do
-    settings <- loadAppSettings [configSettingsYml] [] useEnv
+    settings <- getAppSettings
     foundation <- makeFoundation settings
-    app <- makeApplication foundation
     wsettings <- getDevSettings $ warpSettings foundation
+    app <- makeApplication foundation
     return (wsettings, app)
 
+getAppSettings :: IO AppSettings
+getAppSettings = loadAppSettings [configSettingsYml] [] useEnv
+
 -- | main function for use by yesod devel
 develMain :: IO ()
 develMain = develMainHelper getApplicationDev
@@ -161,6 +170,34 @@ appMain = do
     -- Run the application with Warp
     runSettings (warpSettings foundation) app
 
+
+--------------------------------------------------------------
+-- Functions for DevelMain.hs (a way to run the app from GHCi)
+--------------------------------------------------------------
+getApplicationRepl :: IO (Int, App, Application)
+getApplicationRepl = do
+    settings <- getAppSettings
+    foundation <- makeFoundation settings
+    wsettings <- getDevSettings $ warpSettings foundation
+    app1 <- makeApplication foundation
+    return (getPort wsettings, foundation, app1)
+
+shutdownApp :: App -> IO ()
+shutdownApp _ = return ()
+
+
+---------------------------------------------
+-- Functions for use in development with GHCi
+---------------------------------------------
+
+-- | Run a handler
+handler :: Handler a -> IO a
+handler h = getAppSettings >>= makeFoundation >>= flip unsafeHandler h
+
+-- | Run DB queries
+db :: ReaderT SqlBackend (HandlerT App IO) a -> IO a
+db = handler . runDB
+
 {-# START_FILE Foundation.hs #-}
 module Foundation where
 
@@ -171,6 +208,7 @@ import Text.Jasmine         (minifym)
 import Yesod.Auth.BrowserId (authBrowserId)
 import Yesod.Default.Util   (addStaticContentExternal)
 import Yesod.Core.Types     (Logger)
+import qualified Yesod.Core.Unsafe as Unsafe
 
 -- | The foundation datatype for your application. This can be a good place to
 -- keep settings and values requiring initialization before your application
@@ -306,6 +344,9 @@ instance YesodAuthPersist App
 instance RenderMessage App FormMessage where
     renderMessage _ _ = defaultFormMessage
 
+unsafeHandler :: App -> Handler a -> IO a
+unsafeHandler = Unsafe.fakeHandlerGetLogger appLogger
+
 -- Note: Some functionality previously present in the scaffolding has been
 -- moved to documentation in the Wiki. Following are some hopefully helpful
 -- links:
@@ -423,6 +464,7 @@ Flag library-only
     Default:       False
 
 library
+    hs-source-dirs: ., app
     exposed-modules: Application
                      Foundation
                      Import
@@ -458,7 +500,7 @@ library
 
     build-depends: base                          >= 4          && < 5
                  , yesod                         >= 1.4.1      && < 1.5
-                 , yesod-core                    >= 1.4.0      && < 1.5
+                 , yesod-core                    >= 1.4.6      && < 1.5
                  , yesod-auth                    >= 1.4.0      && < 1.5
                  , yesod-static                  >= 1.4.0.3    && < 1.5
                  , yesod-form                    >= 1.4.0      && < 1.5
@@ -695,40 +737,51 @@ import Yesod.Static (staticFiles)
 staticFiles (appStaticDir compileTimeAppSettings)
 
 {-# START_FILE app/DevelMain.hs #-}
--- | Development version to be run inside GHCi.
+-- | Running your app inside GHCi.
 --
--- start this up with:
+-- To start up GHCi for usage with Yesod, first make sure you are in dev mode:
 --
--- cabal repl --ghc-options="-O0 -fobject-code"
+-- > cabal configure -fdev
 --
--- run with:
+-- Note that @yesod devel@ automatically sets the dev flag.
+-- Now launch the repl:
 --
--- :l DevelMain
+-- > cabal repl --ghc-options="-O0 -fobject-code"
--- DevelMain.update
 --
--- You will need to add these packages to your .cabal file
+-- To start your app, run:
--- * foreign-store >= 0.1 (very light-weight)
+--
--- * warp (you already depend on this, it just isn't in your .cabal file)
+-- > :l DevelMain
+-- > DevelMain.update
+--
+-- You can also call @DevelMain.shutdown@ to stop the app
+--
+-- You will need to add the foreign-store package to your .cabal file.
+-- It is very light-weight.
 --
 -- If you don't use cabal repl, you will need
--- to add settings to your .ghci file.
+-- to run the following in GHCi or to add it to
+-- your .ghci file.
 --
 -- :set -DDEVELOPMENT
 --
--- There is more information about using ghci
+-- There is more information about this approach,
 -- on the wiki: https://github.com/yesodweb/yesod/wiki/ghci
 
 module DevelMain where
 
-import Application (getApplicationDev)
+import Prelude
+import Application (getApplicationRepl, shutdownApp)
 
 import Control.Exception (finally)
+import Control.Monad ((>=>))
 import Control.Concurrent
 import Data.IORef
 import Foreign.Store
 import Network.Wai.Handler.Warp
+import GHC.Word
 
 -- | Start or restart the server.
+-- newStore is from foreign-store.
 -- A Store holds onto some data across ghci reloads
 update :: IO ()
 update = do
@@ -741,27 +794,48 @@ update = do
           _ <- storeAction (Store tidStoreNum) (newIORef tid)
           return ()
       -- server is already running
-      Just tidStore ->
+      Just tidStore -> restartAppInNewThread 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
   where
+    doneStore :: Store (MVar ())
     doneStore = Store 0
-    tidStoreNum = 1
 
-    modifyStoredIORef :: Store (IORef a) -> (a -> IO a) -> IO ()
+    -- shut the server down with killThread and wait for the done signal
-    modifyStoredIORef store f = withStore store $ \ref -> do
+    restartAppInNewThread :: Store (IORef ThreadId) -> IO ()
-        v <- readIORef ref
+    restartAppInNewThread tidStore = modifyStoredIORef tidStore $ \tid -> do
-        f v >>= writeIORef ref
+        killThread tid
+        withStore doneStore takeMVar
+        readStore doneStore >>= start
 
--- | Start the server in a separate thread.
+
-start :: MVar () -- ^ Written to when the thread is killed.
+    -- | Start the server in a separate thread.
-      -> IO ThreadId
+    start :: MVar () -- ^ Written to when the thread is killed.
-start done = do
+          -> IO ThreadId
-    (settings,app) <- getApplicationDev
+    start done = do
-    forkIO (finally (runSettings settings app)
+        (port, site, app) <- getApplicationRepl
-                    (putMVar done ()))
+        forkIO (finally (runSettings (setPort port defaultSettings) app)
+                        -- Note that this implies concurrency
+                        -- between shutdownApp and the next app that is starting.
+                        -- Normally this should be fine
+                        (putMVar done () >> shutdownApp site))
+
+-- | kill the server
+shutdown :: IO ()
+shutdown = do
+    mtidStore <- lookupStore tidStoreNum
+    case mtidStore of
+      -- no server running
+      Nothing -> putStrLn "no Yesod app running"
+      Just tidStore -> do
+          withStore tidStore $ readIORef >=> killThread
+          putStrLn "Yesod app is shutdown"
+
+tidStoreNum :: Word32
+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_FILE app/devel.hs #-}
 {-# LANGUAGE PackageImports #-}
@@ -9032,7 +9106,7 @@ module TestImport
 import Application           (makeFoundation)
 import ClassyPrelude         as X
 import Database.Persist      as X hiding (get)
-import Database.Persist.Sql  (SqlPersistM, runSqlPersistMPool)
+import Database.Persist.Sql  (SqlPersistM, SqlBackend, runSqlPersistMPool, rawExecute, rawSql, unSingle, connEscapeName)
 import Foundation            as X
 import Model                 as X
 import Test.Hspec            as X
@@ -9041,8 +9115,12 @@ import Yesod.Test            as X
 
 runDB :: SqlPersistM a -> YesodExample App a
 runDB query = do
-    pool <- fmap appConnPool getTestYesod
+    app <- getTestYesod
-    liftIO $ runSqlPersistMPool query pool
+    liftIO $ runDBWithApp app query
+
+runDBWithApp :: App -> SqlPersistM a -> IO a
+runDBWithApp app query = runSqlPersistMPool query (appConnPool app)
+
 
 withApp :: SpecWith App -> Spec
 withApp = before $ do
@@ -9050,5 +9128,24 @@ withApp = before $ do
         ["config/test-settings.yml", "config/settings.yml"]
         []
         ignoreEnv
-    makeFoundation settings
+    foundation <- makeFoundation settings
+    wipeDB foundation
+    return foundation
 
+-- This function will truncate all of the tables in your database.
+-- 'withApp' calls it before each test, creating a clean environment for each
+-- spec to run in.
+wipeDB :: App -> IO ()
+wipeDB app = do
+    runDBWithApp app $ do
+        tables <- getTables
+        sqlBackend <- ask
+
+        let escapedTables = map (connEscapeName sqlBackend . DBName) tables
+            query = "TRUNCATE TABLE " ++ (intercalate ", " escapedTables)
+        rawExecute query []
+
+getTables :: MonadIO m => ReaderT SqlBackend m [Text]
+getTables = do
+    tables <- rawSql "SELECT table_name FROM information_schema.tables WHERE table_schema = 'public';" []
+    return $ map unSingle tables

yesod-bin/hsfiles/simple.hsfiles

@@ -32,6 +32,11 @@ module Application
     , appMain
     , develMain
     , makeFoundation
+    -- * for DevelMain
+    , getApplicationRepl
+    , shutdownApp
+    -- * for GHCI
+    , handler
     ) where
 
 import Control.Monad.Logger                 (liftLoc)
@@ -40,7 +45,7 @@ import Language.Haskell.TH.Syntax           (qLocation)
 import Network.Wai.Handler.Warp             (Settings, defaultSettings,
                                              defaultShouldDisplayException,
                                              runSettings, setHost,
-                                             setOnException, setPort)
+                                             setOnException, setPort, getPort)
 import Network.Wai.Middleware.RequestLogger (Destination (Logger),
                                              IPAddrSource (..),
                                              OutputFormat (..), destination,
@@ -112,12 +117,15 @@ warpSettings foundation =
 -- | For yesod devel, return the Warp settings and WAI Application.
 getApplicationDev :: IO (Settings, Application)
 getApplicationDev = do
-    settings <- loadAppSettings [configSettingsYml] [] useEnv
+    settings <- getAppSettings
     foundation <- makeFoundation settings
-    app <- makeApplication foundation
     wsettings <- getDevSettings $ warpSettings foundation
+    app <- makeApplication foundation
     return (wsettings, app)
 
+getAppSettings :: IO AppSettings
+getAppSettings = loadAppSettings [configSettingsYml] [] useEnv
+
 -- | main function for use by yesod devel
 develMain :: IO ()
 develMain = develMainHelper getApplicationDev
@@ -142,14 +150,39 @@ appMain = do
     -- Run the application with Warp
     runSettings (warpSettings foundation) app
 
+
+--------------------------------------------------------------
+-- Functions for DevelMain.hs (a way to run the app from GHCi)
+--------------------------------------------------------------
+getApplicationRepl :: IO (Int, App, Application)
+getApplicationRepl = do
+    settings <- getAppSettings
+    foundation <- makeFoundation settings
+    wsettings <- getDevSettings $ warpSettings foundation
+    app1 <- makeApplication foundation
+    return (getPort wsettings, foundation, app1)
+
+shutdownApp :: App -> IO ()
+shutdownApp _ = return ()
+
+
+---------------------------------------------
+-- Functions for use in development with GHCi
+---------------------------------------------
+
+-- | Run a handler
+handler :: Handler a -> IO a
+handler h = getAppSettings >>= makeFoundation >>= flip unsafeHandler h
+
 {-# START_FILE Foundation.hs #-}
 module Foundation where
 
 import Import.NoFoundation
-import Text.Hamlet         (hamletFile)
+import Text.Hamlet                 (hamletFile)
-import Text.Jasmine        (minifym)
+import Text.Jasmine                (minifym)
-import Yesod.Core.Types    (Logger)
+import Yesod.Core.Types            (Logger)
-import Yesod.Default.Util  (addStaticContentExternal)
+import Yesod.Default.Util          (addStaticContentExternal)
+import qualified Yesod.Core.Unsafe as Unsafe
 
 -- | The foundation datatype for your application. This can be a good place to
 -- keep settings and values requiring initialization before your application
@@ -244,6 +277,9 @@ instance Yesod App where
 instance RenderMessage App FormMessage where
     renderMessage _ _ = defaultFormMessage
 
+unsafeHandler :: App -> Handler a -> IO a
+unsafeHandler = Unsafe.fakeHandlerGetLogger appLogger
+
 -- Note: Some functionality previously present in the scaffolding has been
 -- moved to documentation in the Wiki. Following are some hopefully helpful
 -- links:
@@ -346,6 +382,7 @@ Flag library-only
     Default:       False
 
 library
+    hs-source-dirs: ., app
     exposed-modules: Application
                      Foundation
                      Import
@@ -380,7 +417,7 @@ library
 
     build-depends: base                          >= 4          && < 5
                  , yesod                         >= 1.4.1      && < 1.5
-                 , yesod-core                    >= 1.4.0      && < 1.5
+                 , yesod-core                    >= 1.4.6      && < 1.5
                  , yesod-static                  >= 1.4.0.3    && < 1.5
                  , yesod-form                    >= 1.4.0      && < 1.5
                  , classy-prelude                >= 0.10.2
@@ -604,40 +641,51 @@ import Yesod.Static (staticFiles)
 staticFiles (appStaticDir compileTimeAppSettings)
 
 {-# START_FILE app/DevelMain.hs #-}
--- | Development version to be run inside GHCi.
+-- | Running your app inside GHCi.
 --
--- start this up with:
+-- To start up GHCi for usage with Yesod, first make sure you are in dev mode:
 --
--- cabal repl --ghc-options="-O0 -fobject-code"
+-- > cabal configure -fdev
 --
--- run with:
+-- Note that @yesod devel@ automatically sets the dev flag.
+-- Now launch the repl:
 --
--- :l DevelMain
+-- > cabal repl --ghc-options="-O0 -fobject-code"
--- DevelMain.update
 --
--- You will need to add these packages to your .cabal file
+-- To start your app, run:
--- * foreign-store >= 0.1 (very light-weight)
+--
--- * warp (you already depend on this, it just isn't in your .cabal file)
+-- > :l DevelMain
+-- > DevelMain.update
+--
+-- You can also call @DevelMain.shutdown@ to stop the app
+--
+-- You will need to add the foreign-store package to your .cabal file.
+-- It is very light-weight.
 --
 -- If you don't use cabal repl, you will need
--- to add settings to your .ghci file.
+-- to run the following in GHCi or to add it to
+-- your .ghci file.
 --
 -- :set -DDEVELOPMENT
 --
--- There is more information about using ghci
+-- There is more information about this approach,
 -- on the wiki: https://github.com/yesodweb/yesod/wiki/ghci
 
 module DevelMain where
 
-import Application (getApplicationDev)
+import Prelude
+import Application (getApplicationRepl, shutdownApp)
 
 import Control.Exception (finally)
+import Control.Monad ((>=>))
 import Control.Concurrent
 import Data.IORef
 import Foreign.Store
 import Network.Wai.Handler.Warp
+import GHC.Word
 
 -- | Start or restart the server.
+-- newStore is from foreign-store.
 -- A Store holds onto some data across ghci reloads
 update :: IO ()
 update = do
@@ -650,27 +698,48 @@ update = do
           _ <- storeAction (Store tidStoreNum) (newIORef tid)
           return ()
       -- server is already running
-      Just tidStore ->
+      Just tidStore -> restartAppInNewThread 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
   where
+    doneStore :: Store (MVar ())
     doneStore = Store 0
-    tidStoreNum = 1
 
-    modifyStoredIORef :: Store (IORef a) -> (a -> IO a) -> IO ()
+    -- shut the server down with killThread and wait for the done signal
-    modifyStoredIORef store f = withStore store $ \ref -> do
+    restartAppInNewThread :: Store (IORef ThreadId) -> IO ()
-        v <- readIORef ref
+    restartAppInNewThread tidStore = modifyStoredIORef tidStore $ \tid -> do
-        f v >>= writeIORef ref
+        killThread tid
+        withStore doneStore takeMVar
+        readStore doneStore >>= start
 
--- | Start the server in a separate thread.
+
-start :: MVar () -- ^ Written to when the thread is killed.
+    -- | Start the server in a separate thread.
-      -> IO ThreadId
+    start :: MVar () -- ^ Written to when the thread is killed.
-start done = do
+          -> IO ThreadId
-    (settings,app) <- getApplicationDev
+    start done = do
-    forkIO (finally (runSettings settings app)
+        (port, site, app) <- getApplicationRepl
-                    (putMVar done ()))
+        forkIO (finally (runSettings (setPort port defaultSettings) app)
+                        -- Note that this implies concurrency
+                        -- between shutdownApp and the next app that is starting.
+                        -- Normally this should be fine
+                        (putMVar done () >> shutdownApp site))
+
+-- | kill the server
+shutdown :: IO ()
+shutdown = do
+    mtidStore <- lookupStore tidStoreNum
+    case mtidStore of
+      -- no server running
+      Nothing -> putStrLn "no Yesod app running"
+      Just tidStore -> do
+          withStore tidStore $ readIORef >=> killThread
+          putStrLn "Yesod app is shutdown"
+
+tidStoreNum :: Word32
+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_FILE app/devel.hs #-}
 {-# LANGUAGE PackageImports #-}

yesod-bin/hsfiles/sqlite.hsfiles

@@ -32,6 +32,12 @@ module Application
     , appMain
     , develMain
     , makeFoundation
+    -- * for DevelMain
+    , getApplicationRepl
+    , shutdownApp
+    -- * for GHCI
+    , handler
+    , db
     ) where
 
 import Control.Monad.Logger                 (liftLoc, runLoggingT)
@@ -42,7 +48,7 @@ import Language.Haskell.TH.Syntax           (qLocation)
 import Network.Wai.Handler.Warp             (Settings, defaultSettings,
                                              defaultShouldDisplayException,
                                              runSettings, setHost,
-                                             setOnException, setPort)
+                                             setOnException, setPort, getPort)
 import Network.Wai.Middleware.RequestLogger (Destination (Logger),
                                              IPAddrSource (..),
                                              OutputFormat (..), destination,
@@ -131,12 +137,15 @@ warpSettings foundation =
 -- | For yesod devel, return the Warp settings and WAI Application.
 getApplicationDev :: IO (Settings, Application)
 getApplicationDev = do
-    settings <- loadAppSettings [configSettingsYml] [] useEnv
+    settings <- getAppSettings
     foundation <- makeFoundation settings
-    app <- makeApplication foundation
     wsettings <- getDevSettings $ warpSettings foundation
+    app <- makeApplication foundation
     return (wsettings, app)
 
+getAppSettings :: IO AppSettings
+getAppSettings = loadAppSettings [configSettingsYml] [] useEnv
+
 -- | main function for use by yesod devel
 develMain :: IO ()
 develMain = develMainHelper getApplicationDev
@@ -161,6 +170,34 @@ appMain = do
     -- Run the application with Warp
     runSettings (warpSettings foundation) app
 
+
+--------------------------------------------------------------
+-- Functions for DevelMain.hs (a way to run the app from GHCi)
+--------------------------------------------------------------
+getApplicationRepl :: IO (Int, App, Application)
+getApplicationRepl = do
+    settings <- getAppSettings
+    foundation <- makeFoundation settings
+    wsettings <- getDevSettings $ warpSettings foundation
+    app1 <- makeApplication foundation
+    return (getPort wsettings, foundation, app1)
+
+shutdownApp :: App -> IO ()
+shutdownApp _ = return ()
+
+
+---------------------------------------------
+-- Functions for use in development with GHCi
+---------------------------------------------
+
+-- | Run a handler
+handler :: Handler a -> IO a
+handler h = getAppSettings >>= makeFoundation >>= flip unsafeHandler h
+
+-- | Run DB queries
+db :: ReaderT SqlBackend (HandlerT App IO) a -> IO a
+db = handler . runDB
+
 {-# START_FILE Foundation.hs #-}
 module Foundation where
 
@@ -171,6 +208,7 @@ import Text.Jasmine         (minifym)
 import Yesod.Auth.BrowserId (authBrowserId)
 import Yesod.Default.Util   (addStaticContentExternal)
 import Yesod.Core.Types     (Logger)
+import qualified Yesod.Core.Unsafe as Unsafe
 
 -- | The foundation datatype for your application. This can be a good place to
 -- keep settings and values requiring initialization before your application
@@ -306,6 +344,9 @@ instance YesodAuthPersist App
 instance RenderMessage App FormMessage where
     renderMessage _ _ = defaultFormMessage
 
+unsafeHandler :: App -> Handler a -> IO a
+unsafeHandler = Unsafe.fakeHandlerGetLogger appLogger
+
 -- Note: Some functionality previously present in the scaffolding has been
 -- moved to documentation in the Wiki. Following are some hopefully helpful
 -- links:
@@ -423,6 +464,7 @@ Flag library-only
     Default:       False
 
 library
+    hs-source-dirs: ., app
     exposed-modules: Application
                      Foundation
                      Import
@@ -458,7 +500,7 @@ library
 
     build-depends: base                          >= 4          && < 5
                  , yesod                         >= 1.4.1      && < 1.5
-                 , yesod-core                    >= 1.4.0      && < 1.5
+                 , yesod-core                    >= 1.4.6      && < 1.5
                  , yesod-auth                    >= 1.4.0      && < 1.5
                  , yesod-static                  >= 1.4.0.3    && < 1.5
                  , yesod-form                    >= 1.4.0      && < 1.5
@@ -695,40 +737,51 @@ import Yesod.Static (staticFiles)
 staticFiles (appStaticDir compileTimeAppSettings)
 
 {-# START_FILE app/DevelMain.hs #-}
--- | Development version to be run inside GHCi.
+-- | Running your app inside GHCi.
 --
--- start this up with:
+-- To start up GHCi for usage with Yesod, first make sure you are in dev mode:
 --
--- cabal repl --ghc-options="-O0 -fobject-code"
+-- > cabal configure -fdev
 --
--- run with:
+-- Note that @yesod devel@ automatically sets the dev flag.
+-- Now launch the repl:
 --
--- :l DevelMain
+-- > cabal repl --ghc-options="-O0 -fobject-code"
--- DevelMain.update
 --
--- You will need to add these packages to your .cabal file
+-- To start your app, run:
--- * foreign-store >= 0.1 (very light-weight)
+--
--- * warp (you already depend on this, it just isn't in your .cabal file)
+-- > :l DevelMain
+-- > DevelMain.update
+--
+-- You can also call @DevelMain.shutdown@ to stop the app
+--
+-- You will need to add the foreign-store package to your .cabal file.
+-- It is very light-weight.
 --
 -- If you don't use cabal repl, you will need
--- to add settings to your .ghci file.
+-- to run the following in GHCi or to add it to
+-- your .ghci file.
 --
 -- :set -DDEVELOPMENT
 --
--- There is more information about using ghci
+-- There is more information about this approach,
 -- on the wiki: https://github.com/yesodweb/yesod/wiki/ghci
 
 module DevelMain where
 
-import Application (getApplicationDev)
+import Prelude
+import Application (getApplicationRepl, shutdownApp)
 
 import Control.Exception (finally)
+import Control.Monad ((>=>))
 import Control.Concurrent
 import Data.IORef
 import Foreign.Store
 import Network.Wai.Handler.Warp
+import GHC.Word
 
 -- | Start or restart the server.
+-- newStore is from foreign-store.
 -- A Store holds onto some data across ghci reloads
 update :: IO ()
 update = do
@@ -741,27 +794,48 @@ update = do
           _ <- storeAction (Store tidStoreNum) (newIORef tid)
           return ()
       -- server is already running
-      Just tidStore ->
+      Just tidStore -> restartAppInNewThread 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
   where
+    doneStore :: Store (MVar ())
     doneStore = Store 0
-    tidStoreNum = 1
 
-    modifyStoredIORef :: Store (IORef a) -> (a -> IO a) -> IO ()
+    -- shut the server down with killThread and wait for the done signal
-    modifyStoredIORef store f = withStore store $ \ref -> do
+    restartAppInNewThread :: Store (IORef ThreadId) -> IO ()
-        v <- readIORef ref
+    restartAppInNewThread tidStore = modifyStoredIORef tidStore $ \tid -> do
-        f v >>= writeIORef ref
+        killThread tid
+        withStore doneStore takeMVar
+        readStore doneStore >>= start
 
--- | Start the server in a separate thread.
+
-start :: MVar () -- ^ Written to when the thread is killed.
+    -- | Start the server in a separate thread.
-      -> IO ThreadId
+    start :: MVar () -- ^ Written to when the thread is killed.
-start done = do
+          -> IO ThreadId
-    (settings,app) <- getApplicationDev
+    start done = do
-    forkIO (finally (runSettings settings app)
+        (port, site, app) <- getApplicationRepl
-                    (putMVar done ()))
+        forkIO (finally (runSettings (setPort port defaultSettings) app)
+                        -- Note that this implies concurrency
+                        -- between shutdownApp and the next app that is starting.
+                        -- Normally this should be fine
+                        (putMVar done () >> shutdownApp site))
+
+-- | kill the server
+shutdown :: IO ()
+shutdown = do
+    mtidStore <- lookupStore tidStoreNum
+    case mtidStore of
+      -- no server running
+      Nothing -> putStrLn "no Yesod app running"
+      Just tidStore -> do
+          withStore tidStore $ readIORef >=> killThread
+          putStrLn "Yesod app is shutdown"
+
+tidStoreNum :: Word32
+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_FILE app/devel.hs #-}
 {-# LANGUAGE PackageImports #-}

yesod-bin/yesod-bin.cabal

@@ -1,5 +1,5 @@
 name:            yesod-bin
-version:         1.4.3.3
+version:         1.4.3.4
 license:         MIT
 license-file:    LICENSE
 author:          Michael Snoyman <michael@snoyman.com>