Auto-recovering AMQP session using Data.Pool from resource-pool package.

scotty-amqp.hs

{-# LANGUAGE OverloadedStrings #-}

import Web.Scotty
import Network.AMQP

import Control.Monad.Trans (liftIO)
import qualified Control.Exception as E
import qualified Data.Text.Lazy as TL
import qualified Data.ByteString.Lazy.Char8 as LBS

import Data.Pool

main = do
    amqp <- openConnection "127.0.0.1" "/" "guest" "guest" `amqpPool` 2

    let send msg = withResource amqp $ \(_, chan) -> publishMsg chan "poop" "scotty" $ newMsg { msgBody = LBS.pack msg }

    scotty 8000 $ do
        get "/" $ do
            html "<form method=\"POST\"><input name=\"haha\"/><input type=\"submit\"/></form>"

        post "/" $ do
            haha <- param "haha"
            liftIO $ send haha
            text $ TL.pack haha

amqpPool new size = createPool create destroy 1 3600 size
    where
        create = do
            conn <- new
            chan <- openChannel conn -- throws up when server's not yet available
            return (conn, chan)

        destroy (conn, _) = closeConnection conn