Main.hs

import qualified Control.Distributed.Process as Process

data Config = Config
    { uiPort :: Int
    , dbType :: DbBackend
    , folder :: String
    , testsList :: Scheduler.RunSchedule
    }

newtype App a = App
    { runApp :: ReaderT Config Process.Process a
    } deriving (Monad, Functor, Applicative, MonadIO)

mainProcess config = do
    port <- readPort "WRECKER_PORT" 10500
    backend <- LocalNet.initializeBackend "127.0.0.1" (show @Int port) Node.initRemoteTable
    LocalNet.startMaster backend $ \slaves -> do runReaderT (runApp (startUI backend slaves)) config

getConfig :: IO Config
getConfig = do
    uiPort <- readPort "WRECKER_UI_PORT" 3000
    dbType <- selectDatabaseType
    folder <- findAssetsFolder
    testsList <- Scheduler.emptyRunSchedule
    return (Config {..})

startUI :: LocalNet.Backend -> [NodeId] -> App ()
startUI backend slaves = do
    self <- Process.getSelfPid -- Oops... cannot match App with Process.Process
    liftIO $ do
        putStrLn $ show self
        putStrLn ("Slaves: " ++ show slaves)
        withDb dbType $ \db ->
            liftIO $ -- We're inside the DbMonad, so the results needs to be converted back to IO
             do
                runMigrations db
                scheduler <- async (Scheduler.runScheduler db testsList)
                link scheduler
                routes uiPort folder db testsList