Web.Spock.Worker

Define a Worker

type WorkHandler conn sess st err a = a -> ExceptT (InternalError err) (WebStateM conn sess st) WorkResult

Describe how you want jobs in the queue to be performed

data WorkerConfig

Configure how the worker handles it's task and define the queue size

Constructors

WorkerConfig

Fields

• wc_queueLimit :: Int
• wc_concurrent :: WorkerConcurrentStrategy

data WorkerConcurrentStrategy

Configure the concurrent behaviour of a worker. If you want tasks executed concurrently, consider using WorkerConcurrentBounded

Constructors

WorkerNoConcurrency

WorkerConcurrentBounded Int

WorkerConcurrentUnbounded

data WorkerDef conn sess st err a

Define a worker

Constructors

WorkerDef

Fields

• wd_config :: WorkerConfig
• wd_handler :: WorkHandler conn sess st err a
• wd_errorHandler :: ErrorHandler conn sess st err a

newWorker :: (MonadTrans t, Monad (t (WebStateM conn sess st))) => WorkerDef conn sess st err a -> t (WebStateM conn sess st) (WorkQueue a)

Create a new background worker and limit the size of the job queue.

data WorkResult

Describes the outcome of a job after completion. You can repeat jobs

Constructors

WorkComplete

WorkError

WorkRepeatIn NominalDiffTime

WorkRepeatAt UTCTime

Instances

Eq WorkResult

Methods

(==) :: WorkResult -> WorkResult -> Bool

(/=) :: WorkResult -> WorkResult -> Bool

Show WorkResult

Methods

showsPrec :: Int -> WorkResult -> ShowS

show :: WorkResult -> String

showList :: [WorkResult] -> ShowS

Enqueue work

data WorkQueue a

The queue containing scheduled jobs

data WorkExecution

Describes when a job should be executed

Constructors

WorkNow

WorkIn NominalDiffTime

WorkAt UTCTime

addWork :: MonadIO m => WorkExecution -> a -> WorkQueue a -> m ()

Add a new job to the background worker. If the queue is full this will block

Error Handeling

data ErrorHandler conn sess st err a

Describe how you want to handle errors. Make sure you catch all exceptions that can happen inside this handler, otherwise the worker will crash!

Constructors

ErrorHandlerIO (InternalError err -> a -> IO WorkResult)

ErrorHandlerSpock (InternalError err -> a -> WebStateM conn sess st WorkResult)

data InternalError a

An error from a worker

Constructors

InternalErrorMsg String

InternalError a