System.Cron.Schedule

main :: IO ()
main = do
       ...
       tids <- execSchedule $ do
           addJob job1 "* * * * *"
           addJob job2 "0 * * * *"
       print tids
       ...

job1 :: IO ()
job1 = putStrLn "Job 1"

job2 :: IO ()
job2 = putStrLn "Job 2"

Documentation

data Job

Scheduling Monad

Constructors

Job CronSchedule (IO ())

Instances

Show Job

Methods

showsPrec :: Int -> Job -> ShowS

show :: Job -> String

showList :: [Job] -> ShowS

data ScheduleError

Constructors

ParseError String

Instances

Show ScheduleError

Methods

showsPrec :: Int -> ScheduleError -> ShowS

show :: ScheduleError -> String

showList :: [ScheduleError] -> ShowS

Monad m => MonadError ScheduleError (ScheduleT m)

Methods

throwError :: ScheduleError -> ScheduleT m a

catchError :: ScheduleT m a -> (ScheduleError -> ScheduleT m a) -> ScheduleT m a

type Schedule = ScheduleT Identity

newtype ScheduleT m a

Constructors

ScheduleT

Fields

• unSchedule :: StateT Jobs (ExceptT ScheduleError m) a

Instances

Monad m => MonadError ScheduleError (ScheduleT m)

Methods

throwError :: ScheduleError -> ScheduleT m a

catchError :: ScheduleT m a -> (ScheduleError -> ScheduleT m a) -> ScheduleT m a

Monad m => Monad (ScheduleT m)

Methods

(>>=) :: ScheduleT m a -> (a -> ScheduleT m b) -> ScheduleT m b

(>>) :: ScheduleT m a -> ScheduleT m b -> ScheduleT m b

return :: a -> ScheduleT m a

fail :: String -> ScheduleT m a

Functor m => Functor (ScheduleT m)

Methods

fmap :: (a -> b) -> ScheduleT m a -> ScheduleT m b

(<$) :: a -> ScheduleT m b -> ScheduleT m a

Monad m => Applicative (ScheduleT m)

Methods

pure :: a -> ScheduleT m a

(<*>) :: ScheduleT m (a -> b) -> ScheduleT m a -> ScheduleT m b

(*>) :: ScheduleT m a -> ScheduleT m b -> ScheduleT m b

(<*) :: ScheduleT m a -> ScheduleT m b -> ScheduleT m a

Monad m => MonadSchedule (ScheduleT m)

Methods

addJob :: IO () -> Text -> ScheduleT m ()

class MonadSchedule m where

Minimal complete definition

addJob

Methods

addJob :: IO () -> Text -> m ()

Instances

Monad m => MonadSchedule (ScheduleT m)

Methods

addJob :: IO () -> Text -> ScheduleT m ()

runSchedule :: Schedule a -> Either ScheduleError (a, [Job])

runScheduleT :: ScheduleT m a -> m (Either ScheduleError (a, [Job]))

execSchedule :: Schedule () -> IO [ThreadId]

Schedule all of the jobs to run at appropriate intervals. Each job that is launched gets a scheduling thread to itself. Each time a scheduling thread launches a job, the job is forked onto a new thread. This means that if a job throws an excpetion in IO, its thread will be killed, but it will continue to be scheduled in the future.