lebd/src/Application.hs

208 lines
7.9 KiB
Haskell
Raw Normal View History

{-# LANGUAGE CPP #-}
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE NoImplicitPrelude #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE RecordWildCards #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
module Application
( getApplicationDev
, appMain
, develMain
, makeFoundation
, makeLogWare
-- * for DevelMain
, getApplicationRepl
, shutdownApp
-- * for GHCI
, handler
, db
) where
#if MIN_VERSION_base(4,9,0)
import Control.Concurrent (forkOSWithUnmask)
#else
import GHC.IO (unsafeUnmask)
#endif
import Control.Monad.Logger (liftLoc, runLoggingT)
import Database.Persist.MySQL (createMySQLPool, myConnInfo,
myPoolSize, runSqlPool)
import qualified Database.MySQL.Base as MySQL
import Import
import Language.Haskell.TH.Syntax (qLocation)
import Network.Wai (Middleware)
import Network.Wai.Handler.Warp (Settings, defaultSettings,
defaultShouldDisplayException,
runSettings, setHost,
setFork, setOnOpen, setOnClose,
setOnException, setPort, getPort)
import Network.Wai.Middleware.RequestLogger (Destination (Logger),
IPAddrSource (..),
OutputFormat (..), destination,
mkRequestLogger, outputFormat)
import System.Log.FastLogger (defaultBufSize, newStdoutLoggerSet,
toLogStr)
-- Import all relevant handler modules here.
-- Don't forget to add new modules to your cabal file!
import Handler.Common
import Handler.Home
-- This line actually creates our YesodDispatch instance. It is the second half
-- of the call to mkYesodData which occurs in Foundation.hs. Please see the
-- comments there for more details.
mkYesodDispatch "App" resourcesApp
-- | This function allocates resources (such as a database connection pool),
-- performs initialization and returns a foundation datatype value. This is also
-- the place to put your migrate statements to have automatic database
-- migrations handled by Yesod.
makeFoundation :: AppSettings -> IO App
makeFoundation appSettings = do
-- Some basic initializations: HTTP connection manager, logger, and static
-- subsite.
appHttpManager <- newManager
appLogger <- newStdoutLoggerSet defaultBufSize >>= makeYesodLogger
appStatic <-
(if appMutableStatic appSettings then staticDevel else static)
(appStaticDir appSettings)
-- See http://www.yesodweb.com/blog/2016/11/use-mysql-safely-in-yesod
MySQL.initLibrary
-- We need a log function to create a connection pool. We need a connection
-- pool to create our foundation. And we need our foundation to get a
-- logging function. To get out of this loop, we initially create a
-- temporary foundation without a real connection pool, get a log function
-- from there, and then create the real foundation.
let mkFoundation appConnPool = App {..}
-- The App {..} syntax is an example of record wild cards. For more
-- information, see:
-- https://ocharles.org.uk/blog/posts/2014-12-04-record-wildcards.html
tempFoundation = mkFoundation $ error "connPool forced in tempFoundation"
logFunc = messageLoggerSource tempFoundation appLogger
-- Create the database connection pool
pool <- flip runLoggingT logFunc $ createMySQLPool
(myConnInfo $ appDatabaseConf appSettings)
(myPoolSize $ appDatabaseConf appSettings)
-- Perform database migration using our application's logging settings.
runLoggingT (runSqlPool (runMigration migrateAll) pool) logFunc
-- Return the foundation
return $ mkFoundation pool
-- | Convert our foundation to a WAI Application by calling @toWaiAppPlain@ and
-- applying some additional middlewares.
makeApplication :: App -> IO Application
makeApplication foundation = do
logWare <- makeLogWare foundation
-- Create the WAI application and apply middlewares
appPlain <- toWaiAppPlain foundation
return $ logWare $ defaultMiddlewaresNoLogging appPlain
makeLogWare :: App -> IO Middleware
makeLogWare foundation =
mkRequestLogger def
{ outputFormat =
if appDetailedRequestLogging $ appSettings foundation
then Detailed True
else Apache
(if appIpFromHeader $ appSettings foundation
then FromFallback
else FromSocket)
, destination = Logger $ loggerSet $ appLogger foundation
}
#if ! MIN_VERSION_base(4,9,0)
forkOSWithUnmask :: ((forall a . IO a -> IO a) -> IO ()) -> IO ThreadId
forkOSWithUnmask io = forkOS (io unsafeUnmask)
#endif
-- | Warp settings for the given foundation value.
-- Use bound threads for thread-safe use of MySQL, and initialise and finalise
-- them: see http://www.yesodweb.com/blog/2016/11/use-mysql-safely-in-yesod
warpSettings :: App -> Settings
warpSettings foundation =
setPort (appPort $ appSettings foundation)
$ setHost (appHost $ appSettings foundation)
$ setOnException (\_req e ->
when (defaultShouldDisplayException e) $ messageLoggerSource
foundation
(appLogger foundation)
$(qLocation >>= liftLoc)
"yesod"
LevelError
(toLogStr $ "Exception from Warp: " ++ show e))
$ setFork (\x -> void $ forkOSWithUnmask x)
$ setOnOpen (const $ MySQL.initThread >> return True)
$ setOnClose (const MySQL.endThread)
defaultSettings
-- | For yesod devel, return the Warp settings and WAI Application.
getApplicationDev :: IO (Settings, Application)
getApplicationDev = do
settings <- getAppSettings
foundation <- makeFoundation settings
wsettings <- getDevSettings $ warpSettings foundation
app <- makeApplication foundation
return (wsettings, app)
getAppSettings :: IO AppSettings
getAppSettings = loadYamlSettings [configSettingsYml] [] useEnv
-- | main function for use by yesod devel
develMain :: IO ()
develMain = develMainHelper getApplicationDev
-- | The @main@ function for an executable running this site.
appMain :: IO ()
appMain = do
-- Get the settings from all relevant sources
settings <- loadYamlSettingsArgs
-- fall back to compile-time values, set to [] to require values at runtime
[configSettingsYmlValue]
-- allow environment variables to override
useEnv
-- Generate the foundation from the settings
foundation <- makeFoundation settings
-- Generate a WAI Application from the foundation
app <- makeApplication foundation
-- 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