gRPC-haskell/examples/echo/echo-hs/EchoClient.hs

47 lines
2.0 KiB
Haskell

{-# LANGUAGE DataKinds #-}
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE GADTs #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE OverloadedLists #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE TypeOperators #-}
import Control.Monad
import Data.ByteString (ByteString)
import Data.Maybe (fromMaybe)
import qualified Data.Text.Lazy as TL
import Echo
import Network.GRPC.HighLevel.Client
import Network.GRPC.LowLevel
import Options.Generic
import Prelude hiding (FilePath)
data Args = Args
{ bind :: Maybe ByteString <?> "grpc endpoint hostname (default \"localhost\")"
, port :: Maybe Int <?> "grpc endpoint port (default 50051)"
, payload :: Maybe TL.Text <?> "string to echo (default \"hullo!\")"
} deriving (Generic, Show)
instance ParseRecord Args
main :: IO ()
main = do
Args{..} <- getRecord "Runs the echo client"
let
pay = fromMaybe "hullo!" . unHelpful $ payload
rqt = EchoRequest pay
expected = EchoResponse pay
cfg = ClientConfig
(Host . fromMaybe "localhost" . unHelpful $ bind)
(Port . fromMaybe 50051 . unHelpful $ port)
[] Nothing Nothing
withGRPC $ \g -> withClient g cfg $ \c -> do
Echo{..} <- echoClient c
echoDoEcho (ClientNormalRequest rqt 5 mempty) >>= \case
ClientNormalResponse rsp _ _ StatusOk _
| rsp == expected -> return ()
| otherwise -> fail $ "Got unexpected response: '" ++ show rsp ++ "', expected: '" ++ show expected ++ "'"
ClientNormalResponse _ _ _ st _ -> fail $ "Got unexpected status " ++ show st ++ " from call, expecting StatusOk"
ClientErrorResponse e -> fail $ "Got client error: " ++ show e
putStrLn $ "echo-client success: sent " ++ show pay ++ ", got " ++ show pay