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

data ScheduleError

Constructors

ParseError String

Instances

Show ScheduleError

Monad m => MonadError ScheduleError (ScheduleT m)

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)

Monad m => Monad (ScheduleT m)

Functor m => Functor (ScheduleT m)

Monad m => Applicative (ScheduleT m)

Monad m => MonadSchedule (ScheduleT m)

class MonadSchedule m where

Methods

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

Instances

Monad m => MonadSchedule (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.