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Versions [RSS] [faq] 0.2.0, 0.2.1, 0.2.2, 0.2.3, 0.2.4, 0.2.5, 0.3.2
Dependencies aeson, amqp, amqp-worker, base (>=4.9 && <5), bytestring, data-default, exceptions, monad-control, monad-loops, mtl, resource-pool, split, text, transformers-base [details]
License BSD-3-Clause
Copyright Orbital Labs
Author Sean Hess
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Source repo head: git clone
Uploaded by seanhess at 2019-04-12T16:28:05Z
Distributions NixOS:0.3.2
Executables example
Downloads 4043 total (16 in the last 30 days)
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Status Hackage Matrix CI
Docs available [build log]
Last success reported on 2019-04-12 [all 1 reports]


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Readme for amqp-worker-0.3.2

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AMQP Worker

Type-safe AMQP workers. Compatible with RabbitMQ

{-# LANGUAGE DeriveGeneric     #-}
{-# LANGUAGE OverloadedStrings #-}
module Main where

import           Control.Concurrent      (forkIO)
import           Control.Monad.Catch     (SomeException)
import           Data.Aeson              (FromJSON, ToJSON)
import           Data.Function           ((&))
import           Data.Text               (Text, pack)
import           GHC.Generics            (Generic)
import           Network.AMQP.Worker     (Connection, Message (..),
                                          WorkerException, def, fromURI)
import qualified Network.AMQP.Worker     as Worker
import           Network.AMQP.Worker.Key
import           System.IO               (BufferMode (..), hSetBuffering,
                                          stderr, stdout)

data TestMessage = TestMessage
  { greeting :: Text }
  deriving (Generic, Show, Eq)

instance FromJSON TestMessage
instance ToJSON TestMessage

newMessages :: Key Routing TestMessage
newMessages = key "messages" & word "new"

results :: Key Routing Text
results = key "results"

anyMessages :: Key Binding TestMessage
anyMessages = key "messages" & star

example :: IO ()
example = do

  -- connect
  conn <- Worker.connect (fromURI "amqp://guest:guest@localhost:5672")

  let handleAnyMessages = Worker.topic anyMessages "handleAnyMessage"

  -- initialize the queues
  Worker.bindQueue conn ( newMessages)
  Worker.bindQueue conn ( results)

  -- topic queue!
  Worker.bindQueue conn handleAnyMessages

  putStrLn "Enter a message"
  msg <- getLine

  -- publish a message
  putStrLn "Publishing a message"
  Worker.publish conn newMessages (TestMessage $ pack msg)

  -- create a worker, the program loops here
  _ <- forkIO $ Worker.worker conn def ( newMessages) onError (onMessage conn)
  _ <- forkIO $ Worker.worker conn def (handleAnyMessages) onError (onMessage conn)

  putStrLn "Press any key to exit"
  _ <- getLine
  return ()

onMessage :: Connection -> Message TestMessage -> IO ()
onMessage conn m = do
  let testMessage = value m
  putStrLn "Got Message"
  print testMessage
  Worker.publish conn results (greeting testMessage)

onError :: WorkerException SomeException -> IO ()
onError e = do
  putStrLn "Do something with errors"
  print e

main :: IO ()
main = do
  hSetBuffering stdout LineBuffering
  hSetBuffering stderr LineBuffering