Postgres.Notification

(source)

Definitions

record Notification : Type

Totality: total
Visibility: public export
Constructor:

MkNotification : String -> String -> Notification

Projections:

.channel : Notification -> String
.payload : Notification -> String

.channel : Notification -> String

Visibility: public export

channel : Notification -> String

Visibility: public export

.payload : Notification -> String

Visibility: public export

payload : Notification -> String

Visibility: public export

pgListen : String -> Conn -> IO ResultStatus

  Start listening for notifications on the given channel.

Visibility: export

pgNextNotification : Conn -> IO (Maybe Notification)

  Gets the next notification _of those sitting around locally_.
  Returns `Nothing` if there are no notifications.
  
  See `libpq` documentation on `PQnotifies` for details on the
  distinction between retrieving notifications from the server and
  getting the next notification that has already been retrieved.
  
  NOTE: This function _does_ consume input to make sure no notification
   sent by the server but not processed by the client yet gets
   missed.

Visibility: export

pgNotificationStream : Conn -> Stream (IO Notification)

  Produce a potentially infinite stream of notifications.
  Unlike `pgNextNotificaiton`, this will wait for the server
  to deliver a notification.
  
  This _is_ an infinite sequence with a blocking wait for the
  next notification so it is of somewhat limited utility
  compared to checking for new notifications at a natural point
  in your programs existing logic loop unless your entire loop
  is dictated by notification arrival anyway.

Visibility: export