Safe Haskell	Safe-Inferred
Language	GHC2021

Data.EventSource

Description

The types and functions for creating EventSource and EventSink handles, intended to be used as an extension point.

A single EventSource and zero or more EventSink handles let an application load and emit an ordered, identified event stream. SQLite is a ready-made implementation.

Synopsis

type EventId = Word64
class HasEventId a where
- getEventId :: a -> EventId
newtype EventSource e m = EventSource {
- sourceEvents :: HasEventId e => ConduitT () e (ResourceT m) ()
}
getEvents :: (HasEventId e, MonadUnliftIO m) => EventSource e m -> m [e]
data EventSink e m = EventSink {
- putEvent :: HasEventId e => e -> m ()
- putEvents :: HasEventId e => [e] -> m ()
}
mkEventSink :: Monad m => (HasEventId e => e -> m ()) -> EventSink e m
putEventsToSinks :: (Monad m, HasEventId e) => [EventSink e m] -> [e] -> m ()

Documentation

type EventId = Word64 Source #

class HasEventId a where Source #

Methods

getEventId :: a -> EventId Source #

Instances

Instances details

HasEventId Word64 Source #
Instance details Defined in Data.EventSource Methods getEventId :: Word64 -> EventId Source #

newtype EventSource e m Source #

Constructors

EventSource
Fields sourceEvents :: HasEventId e => ConduitT () e (ResourceT m) () Stream all events from the event source.

getEvents :: (HasEventId e, MonadUnliftIO m) => EventSource e m -> m [e] Source #

Retrieve all events from the event source as a list.

data EventSink e m Source #

Constructors

EventSink
Fields putEvent :: HasEventId e => e -> m () Send a single event to the event sink. putEvents :: HasEventId e => [e] -> m () Send a batch of events to the event sink.

mkEventSink :: Monad m => (HasEventId e => e -> m ()) -> EventSink e m Source #

Create an EventSink from a single-event function, with a default sequential batch implementation.

putEventsToSinks :: (Monad m, HasEventId e) => [EventSink e m] -> [e] -> m () Source #

Put a list of events to a list of event sinks, batching per sink.