kafka-effectful-0.2.0.0: examples/SyncPublish.hs

{- | Scenario 2 of @producer-best-practices.md@: publish one record
synchronously and print the broker-assigned offset.

Assumes a Kafka broker at localhost:9092 with the topic
@kafka-effectful-sync-demo@ already created (or auto-create enabled).
Change the 'brokerHost' and 'topicName' bindings below if your local
broker lives somewhere else.
-}
module Main (main) where

import Effectful (runEff)
import Effectful.Error.Static (runError)
import Kafka.Effectful
import Kafka.Effectful.Producer (brokersList, extraProp, sendTimeout)
import System.Exit (exitFailure)
import System.IO (hPutStrLn, stderr)

brokerHost :: BrokerAddress
brokerHost = BrokerAddress "localhost:9092"

topicName :: TopicName
topicName = TopicName "kafka-effectful-sync-demo"

producerProps :: ProducerProperties
producerProps =
    brokersList [brokerHost]
        <> sendTimeout (Timeout 10000)
        <> extraProp "enable.idempotence" "true"
        <> extraProp "acks" "all"

record :: ProducerRecord
record =
    ProducerRecord
        { prTopic = topicName
        , prPartition = UnassignedPartition
        , prKey = Just "demo-key"
        , prValue = Just "hello from produceMessageSync"
        , prHeaders = mempty
        }

main :: IO ()
main = do
    result <- runEff . runError @KafkaError $
        runKafkaProducer producerProps $ do
            produceMessageSync record
    case result of
        Right (Offset offset) ->
            putStrLn $ "delivered offset " <> show offset
        Left (_callStack, err) -> do
            hPutStrLn stderr $ "kafka error: " <> show err
            exitFailure