mirror of
https://github.com/unclechu/gRPC-haskell.git
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First draft of a tutorial (#15)
* add basic tutorial, re-export client stuff in HighLevel.Generated * add a relative link in README.md * forgot to document the language extensions * cabal file fixup * more context to compile-proto-file * haskell syntax highlighting in markdown * link to gRPC official tutorials for basic concepts * add a note on how to build the examples * prominent notice of required gRPC version * fix typo * do some error handling, show how to run the example executables * use mapM
This commit is contained in:
parent
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9 changed files with 513 additions and 3 deletions
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@ -7,6 +7,8 @@ have extended and released under the same [`LICENSE`](./LICENSE)
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Installation
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------------
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**The current version of this library requires gRPC version 1.2.0. Newer versions may work but have not been tested.**
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Run the following command from the root of this repository to install the
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`compile-proto-file` executable:
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@ -17,6 +19,8 @@ $ nix-env -iA grpc-haskell -f release.nix
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Usage
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-----
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There is a tutorial [here](examples/tutorial/TUTORIAL.md)
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```bash
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$ compile-proto-file --help
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Dumps a compiled .proto file to stdout
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129
examples/tutorial/Arithmetic.hs
Normal file
129
examples/tutorial/Arithmetic.hs
Normal file
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@ -0,0 +1,129 @@
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{-# LANGUAGE DeriveGeneric #-}
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{-# LANGUAGE DataKinds #-}
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{-# LANGUAGE GADTs #-}
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{-# LANGUAGE OverloadedStrings #-}
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{-# OPTIONS_GHC -fno-warn-unused-imports #-}
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{-# OPTIONS_GHC -fno-warn-name-shadowing #-}
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-- | Generated by Haskell protocol buffer compiler. DO NOT EDIT!
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module Arithmetic where
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import qualified Prelude as Hs
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import qualified Proto3.Suite.DotProto as HsProtobuf
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import qualified Proto3.Suite.Types as HsProtobuf
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import qualified Proto3.Suite.Class as HsProtobuf
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import qualified Proto3.Wire as HsProtobuf
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import Control.Applicative ((<*>), (<|>))
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import qualified Data.Text as Hs (Text)
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import qualified Data.ByteString as Hs
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import qualified Data.String as Hs (fromString)
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import qualified Data.Vector as Hs (Vector)
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import qualified Data.Int as Hs (Int16, Int32, Int64)
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import qualified Data.Word as Hs (Word16, Word32, Word64)
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import GHC.Generics as Hs
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import GHC.Enum as Hs
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import Network.GRPC.HighLevel.Generated as HsGRPC
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import Network.GRPC.HighLevel.Client as HsGRPC
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import Network.GRPC.HighLevel.Server as HsGRPC hiding (serverLoop)
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import Network.GRPC.HighLevel.Server.Unregistered as HsGRPC
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(serverLoop)
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import Network.GRPC.LowLevel.Call as HsGRPC
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data Arithmetic request response = Arithmetic{arithmeticAdd ::
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request 'HsGRPC.Normal TwoInts OneInt ->
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Hs.IO (response 'HsGRPC.Normal OneInt),
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arithmeticRunningSum ::
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request 'HsGRPC.ClientStreaming OneInt OneInt ->
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Hs.IO (response 'HsGRPC.ClientStreaming OneInt)}
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deriving Hs.Generic
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arithmeticServer ::
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Arithmetic HsGRPC.ServerRequest HsGRPC.ServerResponse ->
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HsGRPC.ServiceOptions -> Hs.IO ()
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arithmeticServer
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Arithmetic{arithmeticAdd = arithmeticAdd,
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arithmeticRunningSum = arithmeticRunningSum}
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(ServiceOptions serverHost serverPort useCompression
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userAgentPrefix userAgentSuffix initialMetadata sslConfig logger)
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= (HsGRPC.serverLoop
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HsGRPC.defaultOptions{HsGRPC.optNormalHandlers =
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[(HsGRPC.UnaryHandler
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(HsGRPC.MethodName "/arithmetic.Arithmetic/Add")
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(HsGRPC.convertGeneratedServerHandler arithmeticAdd))],
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HsGRPC.optClientStreamHandlers =
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[(HsGRPC.ClientStreamHandler
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(HsGRPC.MethodName "/arithmetic.Arithmetic/RunningSum")
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(HsGRPC.convertGeneratedServerReaderHandler
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arithmeticRunningSum))],
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HsGRPC.optServerStreamHandlers = [],
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HsGRPC.optBiDiStreamHandlers = [], optServerHost = serverHost,
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optServerPort = serverPort, optUseCompression = useCompression,
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optUserAgentPrefix = userAgentPrefix,
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optUserAgentSuffix = userAgentSuffix,
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optInitialMetadata = initialMetadata, optSSLConfig = sslConfig,
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optLogger = logger})
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arithmeticClient ::
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HsGRPC.Client ->
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Hs.IO (Arithmetic HsGRPC.ClientRequest HsGRPC.ClientResult)
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arithmeticClient client
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= (Hs.pure Arithmetic) <*>
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((Hs.pure (HsGRPC.clientRequest client)) <*>
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(HsGRPC.clientRegisterMethod client
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(HsGRPC.MethodName "/arithmetic.Arithmetic/Add")))
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<*>
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((Hs.pure (HsGRPC.clientRequest client)) <*>
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(HsGRPC.clientRegisterMethod client
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(HsGRPC.MethodName "/arithmetic.Arithmetic/RunningSum")))
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data TwoInts = TwoInts{twoIntsX :: Hs.Int32, twoIntsY :: Hs.Int32}
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deriving (Hs.Show, Hs.Eq, Hs.Ord, Hs.Generic)
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instance HsProtobuf.Named TwoInts where
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nameOf _ = (Hs.fromString "TwoInts")
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instance HsProtobuf.Message TwoInts where
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encodeMessage _ TwoInts{twoIntsX = twoIntsX, twoIntsY = twoIntsY}
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= (Hs.mconcat
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[(HsProtobuf.encodeMessageField (HsProtobuf.FieldNumber 1)
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twoIntsX),
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(HsProtobuf.encodeMessageField (HsProtobuf.FieldNumber 2)
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twoIntsY)])
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decodeMessage _
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= (Hs.pure TwoInts) <*>
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(HsProtobuf.at HsProtobuf.decodeMessageField
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(HsProtobuf.FieldNumber 1))
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<*>
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(HsProtobuf.at HsProtobuf.decodeMessageField
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(HsProtobuf.FieldNumber 2))
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dotProto _
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= [(HsProtobuf.DotProtoField (HsProtobuf.FieldNumber 1)
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(HsProtobuf.Prim HsProtobuf.Int32)
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(HsProtobuf.Single "x")
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[]
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Hs.Nothing),
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(HsProtobuf.DotProtoField (HsProtobuf.FieldNumber 2)
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(HsProtobuf.Prim HsProtobuf.Int32)
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(HsProtobuf.Single "y")
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[]
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Hs.Nothing)]
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data OneInt = OneInt{oneIntResult :: Hs.Int32}
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deriving (Hs.Show, Hs.Eq, Hs.Ord, Hs.Generic)
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instance HsProtobuf.Named OneInt where
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nameOf _ = (Hs.fromString "OneInt")
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instance HsProtobuf.Message OneInt where
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encodeMessage _ OneInt{oneIntResult = oneIntResult}
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= (Hs.mconcat
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[(HsProtobuf.encodeMessageField (HsProtobuf.FieldNumber 1)
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oneIntResult)])
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decodeMessage _
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= (Hs.pure OneInt) <*>
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(HsProtobuf.at HsProtobuf.decodeMessageField
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(HsProtobuf.FieldNumber 1))
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dotProto _
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= [(HsProtobuf.DotProtoField (HsProtobuf.FieldNumber 1)
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(HsProtobuf.Prim HsProtobuf.Int32)
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(HsProtobuf.Single "result")
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[]
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Hs.Nothing)]
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39
examples/tutorial/ArithmeticClient.hs
Normal file
39
examples/tutorial/ArithmeticClient.hs
Normal file
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@ -0,0 +1,39 @@
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{-# LANGUAGE OverloadedStrings #-}
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{-# LANGUAGE OverloadedLists #-}
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{-# LANGUAGE GADTs #-}
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import Arithmetic
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import Network.GRPC.HighLevel.Generated
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clientConfig :: ClientConfig
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clientConfig = ClientConfig { clientServerHost = "localhost"
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, clientServerPort = 50051
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, clientArgs = []
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, clientSSLConfig = Nothing
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}
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main :: IO ()
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main = withGRPCClient clientConfig $ \client -> do
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(Arithmetic arithmeticAdd arithmeticRunningSum) <- arithmeticClient client
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-- Request for the Add RPC
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ClientNormalResponse (OneInt x) _meta1 _meta2 _status _details
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<- arithmeticAdd (ClientNormalRequest (TwoInts 2 2) 1 [])
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putStrLn ("2 + 2 = " ++ show x)
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-- Request for the RunningSum RPC
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ClientWriterResponse reply _streamMeta1 _streamMeta2 streamStatus streamDtls
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<- arithmeticRunningSum $ ClientWriterRequest 1 [] $ \send -> do
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eithers <- mapM send [OneInt 1, OneInt 2, OneInt 3]
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:: IO [Either GRPCIOError ()]
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case sequence eithers of
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Left err -> error ("Error while streaming: " ++ show err)
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Right _ -> return ()
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case reply of
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Just (OneInt y) -> print ("1 + 2 + 3 = " ++ show y)
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Nothing -> putStrLn ("Client stream failed with status "
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++ show streamStatus
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++ " and details "
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++ show streamDtls)
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return ()
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50
examples/tutorial/ArithmeticServer.hs
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50
examples/tutorial/ArithmeticServer.hs
Normal file
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@ -0,0 +1,50 @@
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{-# LANGUAGE DataKinds #-}
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{-# LANGUAGE GADTs #-}
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{-# LANGUAGE OverloadedLists #-}
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{-# LANGUAGE OverloadedStrings #-}
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{-# LANGUAGE BangPatterns #-}
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import Arithmetic
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import Network.GRPC.HighLevel.Generated
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import Data.String (fromString)
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handlers :: Arithmetic ServerRequest ServerResponse
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handlers = Arithmetic { arithmeticAdd = addHandler
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, arithmeticRunningSum = runningSumHandler
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}
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addHandler :: ServerRequest 'Normal TwoInts OneInt
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-> IO (ServerResponse 'Normal OneInt)
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addHandler (ServerNormalRequest _metadata (TwoInts x y)) = do
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let answer = OneInt (x + y)
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return (ServerNormalResponse answer
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[("metadata_key_one", "metadata_value")]
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StatusOk
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"addition is easy!")
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runningSumHandler :: ServerRequest 'ClientStreaming OneInt OneInt
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-> IO (ServerResponse 'ClientStreaming OneInt)
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runningSumHandler req@(ServerReaderRequest metadata recv) =
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loop 0
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where loop !i =
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do msg <- recv
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case msg of
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Left err -> return (ServerReaderResponse
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Nothing
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[]
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StatusUnknown
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(fromString (show err)))
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Right (Just (OneInt x)) -> loop (i + x)
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Right Nothing -> return (ServerReaderResponse
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(Just (OneInt i))
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[]
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StatusOk
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"")
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options :: ServiceOptions
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options = defaultServiceOptions
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main :: IO ()
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main = arithmeticServer handlers options
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216
examples/tutorial/TUTORIAL.md
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216
examples/tutorial/TUTORIAL.md
Normal file
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@ -0,0 +1,216 @@
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## Introduction to gRPC-Haskell
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*This tutorial assumes that you already have a basic understanding of gRPC as well as Haskell.* For an intoduction to the concepts of gRPC, see the [official tutorials](http://www.grpc.io/docs/tutorials/).
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This will go through a basic example of using the library, with the `arithmetic` example in the `examples/arithmetic` directory. After cloning this repository, it would be a good idea to run `stack haddock` from within the repository directory to generate the documentation so you can read more about the functions and types we're using as we go. Also remember that [typed holes](https://wiki.haskell.org/GHC/Typed_holes) can be very handy.
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To build the examples, you can run
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```
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$ stack build --flag grpc-haskell:with-examples
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```
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The gRPC service we will be implementing provides two amazing functions:
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1. `Add`, which adds two integers.
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2. `RunningSum`, which receives a stream of integers from the client and finally returns a single integer that is the sum of all the integers it has received.
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You can run the examples by running `stack exec arithmetic-server` and `stack exec arithmetic-client`.
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### Library Organization
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**tl;dr: you probably only need to import `Network.GRPC.HighLevel.Generated`.** Other modules are exposed for advanced users only.
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This library exposes quite a few modules, but you won't need to worry about most of them. They are currently organized based on the level of abstraction they afford over using the C [gRPC Core library](http://www.grpc.io/grpc/core/) directly:
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* *`Unsafe`* modules directly wrap functions in the gRPC Core library. Using them directly is like using C: you need to think about memory management, pointers, and so on. The rest of the library is built on top of these functions and users of gRPC-haskell should never need to deal with the `Unsafe` modules directly.
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* *`LowLevel`* modules still require an understanding of the gRPC Core library, but guarantee memory and thread safety. Only advanced users with special requirements would use `LowLevel` modules directly.
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* *`HighLevel`* modules give you an opinionated Haskell interface to gRPC that should cover most use cases while (hopefully) being easy to use. You should only need to import the `Network.GRPC.HighLevel.Generated` module to start using the library. If you need to import other modules, we probably forgot to re-export something and you should open an issue or PR.
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### Getting started
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To start out, we need to generate code for our protocol buffers and RPCs. The `compile-proto-file` command is provided as part of `grpc-haskell`. You can either use `stack install` to install the command globally, or use `stack exec` within the `grpc-haskell` directory.
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```
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$ stack exec -- compile-proto-file --proto examples/echo/echo.proto > examples/echo/echo-hs/Echo.hs
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```
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The `.proto` file compiler always names the generated module the same as the `.proto` file, capitalizing the first letter if it is not already. Since our proto file is `arithmetic.proto`, the generated code should be placed in `Arithmetic.hs`.
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The important things to notice in this generated file are:
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1. For each proto message type, an equivalent Haskell type with the same name has been generated.
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2. The `arithmeticServer` function takes a a record containing handlers for each RPC endpoint and some options, and starts a server. So, you just need to call this function to get a server running.
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3, The `arithmeticClient` function takes a `Client` (which is just a proof that the gRPC core has been started) and gives you a record of functions that can be used to run RPCs.
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### The server
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First, we need to turn on some language extensions:
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```haskell
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{-# LANGUAGE DataKinds #-}
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{-# LANGUAGE GADTs #-}
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{-# LANGUAGE OverloadedLists #-}
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{-# LANGUAGE OverloadedStrings #-}
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```
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All we need to do to run a server is call the `arithmeticServer` function:
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```haskell
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main :: IO ()
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main = arithmeticServer handlers options
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```
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So we just need to define `handlers` and `options`.
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`options` is easy-- it's just some basic options for the server. We can just use the default options for now, which will start the server listening on `localhost:50051`:
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```haskell
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options :: ServiceOptions
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options = defaultServiceOptions
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```
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`handlers` is a bit more involved. Its type is `Arithmetic ServerRequest ServerResponse`. Values of this type contain a record field for each RPC defined in your `.proto` file.
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```haskell
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handlers :: Arithmetic ServerRequest ServerResponse
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handlers = Arithmetic { arithmeticAdd = addHandler
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, arithmeticRunningSum = runningSumHandler
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}
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```
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You can think of the handlers as being of type `ServerRequest -> ServerResponse`, though there are a few more type parameters in there. The most important one is the first parameter, which specifies whether the RPC is streaming (`ClientStreaming`, `ServerStreaming`, or `BidiStreaming`) or not (`Normal`).
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The `ServerRequest` passed to your handler contains all the tools you will need to handle the request, including:
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1. The metadata the client sent with the request.
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2. The protocol buffer message sent with the request, which has already been parsed into a Haskell type for you.
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3. If it's a streaming request, you will also be given functions for sending or receiving messages in the stream.
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#### The unary RPC handler for `Add`
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So, let's pattern match on the `ServerRequest` for the `addHandler` function:
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```haskell
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addHandler (ServerNormalRequest metadata (TwoInts x y)) = -- to be continued!
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```
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The body of the `addHandler` function just needs to add `x` and `y` and then bundle the answer up in a `ServerResponse`:
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```haskell
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addHandler (ServerNormalRequest _metadata (TwoInts x y)) = do
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let answer = OneInt (x + y)
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return (ServerNormalResponse answer
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[("metadata_key_one", "metadata_value")]
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StatusOk
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"addition is easy!")
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```
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|
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Since this is a non-streaming "Normal" RPC, we use the the `ServerNormalResponse` constructor. Its parameters are the response message, some (optional) metadata key-value pairs, a status code, and a string with additional details about the status, which would normally be used to explain any errors in handling the request.
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#### The client streaming handler for `RunningSum`
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Now let's make our `runningSumHandler`. Since this is an RPC where the server reads from a stream of numbers, we pattern match on the `ServerReaderRequest` constructor:
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|
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```haskell
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||||
runningSumHandler req@(ServerReaderRequest metadata recv) = -- to be continued!
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||||
```
|
||||
|
||||
Unlike the unary "Normal" request handler, we don't get a message from the client in this pattern match. Instead, we get an IO action `recv`, which we can run to wait for the client to send us another message.
|
||||
|
||||
There are three possibilities when we try to receive another message from the client:
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|
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1. The RPC breaks with some gRPC error, such as losing the connection with the client.
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2. We receive another message from the client.
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3. The client has sent its last message and is waiting for a response.
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||||
|
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We write a simple loop that keeps track of the running sum and finally sends off a `ServerReaderResponse` when the client finishes streaming or an error occurs:
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|
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```haskell
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runningSumHandler req@(ServerReaderRequest metadata recv) =
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loop 0
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||||
where loop !i =
|
||||
do msg <- recv
|
||||
case msg of
|
||||
Left err -> return (ServerReaderResponse
|
||||
Nothing
|
||||
[]
|
||||
StatusUnknown
|
||||
(fromString (show err)))
|
||||
Right (Just (OneInt x)) -> loop (i + x)
|
||||
Right Nothing -> return (ServerReaderResponse
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||||
(Just (OneInt i))
|
||||
[]
|
||||
StatusOk
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||||
"")
|
||||
```
|
||||
|
||||
The `ServerReaderResponse` type is almost the same as `ServerNormalResponse`, except that the first argument, the message to send back to the client, is optional. Otherwise, it takes metadata (which we leave empty), a status code, and a string containing more information about the status code.
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|
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### The client
|
||||
|
||||
The client-side code generated for us is `arithmeticClient`, which takes a `Client` as input and gives us a record containing actions that execute RPCs. To start up the C gRPC library and get a `Client`, we use `withGRPCClient`, which takes a `ClientConfig`:
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|
||||
|
||||
|
||||
```haskell
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clientConfig :: ClientConfig
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||||
clientConfig = ClientConfig { clientServerHost = "localhost"
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||||
, clientServerPort = 50051
|
||||
, clientArgs = []
|
||||
, clientSSLConfig = Nothing
|
||||
}
|
||||
|
||||
main :: IO ()
|
||||
main = withGRPCClient clientConfig $ \client -> do
|
||||
(Arithmetic arithmeticAdd arithmeticRunningSum) <- arithmeticClient client
|
||||
-- to be continued!
|
||||
```
|
||||
|
||||
Now that we are on the client side, the `Arithmetic` record contains functions that make RPC requests. You can think of these functions as roughly having the type `ClientRequest -> ClientResult`. Like before, the particular constructors will vary depending on whether the RPC is streaming or not.
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|
||||
#### Requesting unary RPC
|
||||
|
||||
Here we construct a `ClientNormalRequest`, which takes as input a message, a timeout in seconds, and metadata. The result is a `ClientNormalResponse`, containing the server's response, the initial and trailing metadata for the call, and the status and status details string.
|
||||
|
||||
```haskell
|
||||
-- Request for the Add RPC
|
||||
ClientNormalResponse (OneInt x) _meta1 _meta2 _status _details
|
||||
<- arithmeticAdd (ClientNormalRequest (TwoInts 2 2) 1 [])
|
||||
print ("2 + 2 = " ++ (show x))
|
||||
```
|
||||
|
||||
#### Executing a client streaming RPC
|
||||
|
||||
Doing a streaming request is slightly trickier. As input to the streaming RPC action, we pass in another IO action that tells `grpc-haskell` what to send. It takes a `send` action as input. This is a bit convoluted, but it guarantees that you can't send streaming messages outside of the context of a streaming call!
|
||||
|
||||
```haskell
|
||||
-- Request for the RunningSum RPC
|
||||
ClientWriterResponse reply _streamMeta1 _streamMeta2 streamStatus streamDtls
|
||||
<- arithmeticRunningSum $ ClientWriterRequest 1 [] $ \send -> do
|
||||
eithers <- mapM send [OneInt 1, OneInt 2, OneInt 3]
|
||||
:: IO [Either GRPCIOError ()]
|
||||
case sequence eithers of
|
||||
Left err -> error ("Error while streaming: " ++ show err)
|
||||
Right _ -> return ()
|
||||
```
|
||||
|
||||
Each `send` potentially returns an error message, with the type `Either GRPCIOError ()`. We use `sequence` to run all the `send` actions, and then use `sequence` again to collapse all the `Either`s. If an error is encountered while streaming, there's nothing we can do to salvage the RPC, so a more serious program would need to do some application-specific error-handling. Since this is just a tutorial, we print an error message and exit. Otherwise, we `return ()` to finish sending.
|
||||
|
||||
We can now inspect the `reply` to get our answer to the RPC.
|
||||
|
||||
```haskell
|
||||
case reply of
|
||||
Just (OneInt y) -> print ("1 + 2 + 3 = " ++ show y)
|
||||
Nothing -> putStrLn ("Client stream failed with status "
|
||||
++ show streamStatus
|
||||
++ " and details "
|
||||
++ show streamDtls)
|
||||
```
|
||||
|
||||
To run the examples and see the requests, start the `arithmetic-server` process in the background, and then run the `arithmetic-client` process:
|
||||
|
||||
```
|
||||
$ stack exec -- arithmetic-server &
|
||||
$ stack exec -- arithmetic-client
|
||||
```
|
17
examples/tutorial/arithmetic.proto
Normal file
17
examples/tutorial/arithmetic.proto
Normal file
|
@ -0,0 +1,17 @@
|
|||
syntax = "proto3";
|
||||
package arithmetic;
|
||||
|
||||
service Arithmetic {
|
||||
rpc Add (TwoInts) returns (OneInt) {}
|
||||
|
||||
rpc RunningSum (stream OneInt) returns (OneInt) {}
|
||||
}
|
||||
|
||||
message TwoInts {
|
||||
int32 x = 1;
|
||||
int32 y = 2;
|
||||
}
|
||||
|
||||
message OneInt {
|
||||
int32 result = 1;
|
||||
}
|
|
@ -170,6 +170,51 @@ executable echo-server
|
|||
hs-source-dirs: examples/echo/echo-hs
|
||||
main-is: EchoServer.hs
|
||||
|
||||
|
||||
executable arithmetic-server
|
||||
if flag(with-examples)
|
||||
build-depends:
|
||||
base >=4.8 && <5.0
|
||||
, async
|
||||
, bytestring == 0.10.*
|
||||
, containers ==0.5.*
|
||||
, grpc-haskell
|
||||
, optparse-generic
|
||||
, proto3-suite
|
||||
, proto3-wire
|
||||
, text
|
||||
, vector
|
||||
other-modules:
|
||||
Arithmetic
|
||||
else
|
||||
buildable: False
|
||||
default-language: Haskell2010
|
||||
ghc-options: -Wall -g -threaded -rtsopts -with-rtsopts=-N -O2
|
||||
hs-source-dirs: examples/tutorial/
|
||||
main-is: ArithmeticServer.hs
|
||||
|
||||
executable arithmetic-client
|
||||
if flag(with-examples)
|
||||
build-depends:
|
||||
base >=4.8 && <5.0
|
||||
, async
|
||||
, bytestring == 0.10.*
|
||||
, containers ==0.5.*
|
||||
, grpc-haskell
|
||||
, optparse-generic
|
||||
, proto3-suite
|
||||
, proto3-wire
|
||||
, text
|
||||
, vector
|
||||
other-modules:
|
||||
Arithmetic
|
||||
else
|
||||
buildable: False
|
||||
default-language: Haskell2010
|
||||
ghc-options: -Wall -g -threaded -rtsopts -with-rtsopts=-N -O2
|
||||
hs-source-dirs: examples/tutorial/
|
||||
main-is: ArithmeticClient.hs
|
||||
|
||||
executable echo-client
|
||||
if flag(with-examples)
|
||||
build-depends:
|
||||
|
|
|
@ -28,10 +28,17 @@ module Network.GRPC.HighLevel.Generated (
|
|||
|
||||
-- * Server Auth
|
||||
, ServerSSLConfig(..)
|
||||
|
||||
-- * Client
|
||||
, withGRPCClient
|
||||
, ClientConfig(..)
|
||||
, ClientRequest(..)
|
||||
, ClientResult(..)
|
||||
)
|
||||
where
|
||||
|
||||
import Network.GRPC.HighLevel.Server
|
||||
import Network.GRPC.HighLevel.Client
|
||||
import Network.GRPC.LowLevel
|
||||
import Network.GRPC.LowLevel.Call
|
||||
import System.IO (hPutStrLn, stderr)
|
||||
|
@ -84,3 +91,6 @@ defaultServiceOptions = ServiceOptions
|
|||
, Network.GRPC.HighLevel.Generated.sslConfig = Nothing
|
||||
, Network.GRPC.HighLevel.Generated.logger = hPutStrLn stderr
|
||||
}
|
||||
|
||||
withGRPCClient :: ClientConfig -> (Client -> IO a) -> IO a
|
||||
withGRPCClient c f = withGRPC $ \grpc -> withClient grpc c $ \client -> f client
|
||||
|
|
|
@ -54,8 +54,8 @@ data ClientSSLConfig = ClientSSLConfig
|
|||
|
||||
-- | Configuration necessary to set up a client.
|
||||
|
||||
data ClientConfig = ClientConfig {serverHost :: Host,
|
||||
serverPort :: Port,
|
||||
data ClientConfig = ClientConfig {clientServerHost :: Host,
|
||||
clientServerPort :: Port,
|
||||
clientArgs :: [C.Arg],
|
||||
-- ^ Optional arguments for setting up the
|
||||
-- channel on the client. Supplying an empty
|
||||
|
@ -69,7 +69,7 @@ data ClientConfig = ClientConfig {serverHost :: Host,
|
|||
}
|
||||
|
||||
clientEndpoint :: ClientConfig -> Endpoint
|
||||
clientEndpoint ClientConfig{..} = endpoint serverHost serverPort
|
||||
clientEndpoint ClientConfig{..} = endpoint clientServerHost clientServerPort
|
||||
|
||||
addMetadataCreds :: C.ChannelCredentials
|
||||
-> Maybe C.ClientMetadataCreate
|
||||
|
|
Loading…
Reference in a new issue