Hash2Pub/app/Experiment.hs

52 lines
2 KiB
Haskell

{-# LANGUAGE OverloadedStrings #-}
module Main where
import Control.Concurrent
import Control.Monad (forM_)
import qualified Data.Text.Lazy as Txt
import qualified Data.Text.Lazy.IO as TxtI
import qualified Network.HTTP.Client as HTTP
import System.Environment (getArgs)
import Hash2Pub.PostService (Hashtag, clientPublishPost)
-- configuration constants
timelineFile = "../simulationData/inputs/generated/timeline_sample.csv"
main :: IO ()
main = do
-- read CLI parameters
speedupStr : _ <- getArgs
-- read and parse timeline schedule
-- relying on lazyness of HaskellIO, hoping it does not introduce too strong delays
postEvents <- parseSchedule <$> TxtI.readFile timelineFile
-- actually schedule and send the post events
executeSchedule (read speedupStr) postEvents
pure ()
parseSchedule :: Txt.Text
-> [(Int, Hashtag, (String, Int))] -- ^ [(delay in microseconds, hashtag, (hostname, port))]
parseSchedule = fmap (parseEntry . Txt.split (== ';')) . Txt.lines
where
parseEntry [delayT, contactT, tag] =
(read $ Txt.unpack delayT, tag, read $ Txt.unpack contactT)
parseEntry entry = error $ "invalid schedule input format: " <> show entry
executeSchedule :: Int -- ^ speedup factor
-> [(Int, Hashtag, (String, Int))] -- ^ [(delay in microseconds, hashtag, (hostname, port))]
-> IO ()
executeSchedule speedup events = do
-- initialise HTTP manager
httpMan <- HTTP.newManager HTTP.defaultManagerSettings
forM_ events $ \(delay, tag, (pubHost, pubPort)) -> do
_ <- forkIO $
clientPublishPost httpMan pubHost pubPort ("foobar #" <> tag)
>>= either putStrLn (const $ pure ())
-- while threadDelay gives only minimum delay guarantees, let's hope the
-- additional delays are negligible
-- otherwise: evaluate usage of https://hackage.haskell.org/package/schedule-0.3.0.0/docs/Data-Schedule.html
threadDelay $ delay `div` speedup