diff --git a/CHANGELOG.md b/CHANGELOG.md new file mode 100644 --- /dev/null +++ b/CHANGELOG.md @@ -0,0 +1,5 @@ +# Revision history for mu-haskell + +## 0.1.0.0 -- YYYY-mm-dd + +* First version. Released on an unsuspecting world. diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,202 @@ + + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + + TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + + 1. Definitions. + + "License" shall mean the terms and conditions for use, reproduction, + and distribution as defined by Sections 1 through 9 of this document. + + "Licensor" shall mean the copyright owner or entity authorized by + the copyright owner that is granting the License. + + "Legal Entity" shall mean the union of the acting entity and all + other entities that control, are controlled by, or are under common + control with that entity. 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We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + + Copyright © 2019-2020 47 Degrees. + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/mu-grpc-server.cabal b/mu-grpc-server.cabal new file mode 100644 --- /dev/null +++ b/mu-grpc-server.cabal @@ -0,0 +1,67 @@ +cabal-version: >=1.10 +name: mu-grpc-server +version: 0.1.0.0 +synopsis: gRPC servers for Mu definitions +description: With @mu-grpc-server@ you can easily build gRPC servers for mu-haskell! +license: Apache-2.0 +license-file: LICENSE +author: Alejandro Serrano, Flavio Corpa +maintainer: alejandro.serrano@47deg.com +copyright: Copyright © 2019-2020 +category: Network +build-type: Simple +extra-source-files: CHANGELOG.md +homepage: https://higherkindness.io/mu-haskell/ +bug-reports: https://github.com/higherkindness/mu-haskell/issues + +source-repository head + type: git + location: https://github.com/higherkindness/mu-haskell + +library + exposed-modules: Mu.GRpc.Server + build-depends: base >=4.12 && <5 + , async + , bytestring + , conduit + , http2-grpc-proto3-wire + , http2-grpc-types + , mtl + , mu-protobuf + , mu-rpc + , mu-schema + , sop-core + , stm + , stm-conduit + , wai + , warp + , warp-grpc + , warp-tls + hs-source-dirs: src + default-language: Haskell2010 + ghc-options: -Wall + -fprint-potential-instances + +executable grpc-example-server + main-is: ExampleServer.hs + other-modules: Mu.GRpc.Server + build-depends: base >=4.12 && <5 + , async + , bytestring + , conduit + , http2-grpc-proto3-wire + , http2-grpc-types + , mtl + , mu-protobuf + , mu-rpc + , mu-schema + , sop-core + , stm + , stm-conduit + , wai + , warp + , warp-grpc + , warp-tls + hs-source-dirs: src + default-language: Haskell2010 + ghc-options: -Wall diff --git a/src/ExampleServer.hs b/src/ExampleServer.hs new file mode 100644 --- /dev/null +++ b/src/ExampleServer.hs @@ -0,0 +1,19 @@ +{-# language DataKinds #-} +{-# language OverloadedStrings #-} +{-# language TypeFamilies #-} +module Main where + +import Mu.Adapter.ProtoBuf +import Mu.GRpc.Server +import Mu.Rpc.Examples +import Mu.Schema + +type instance AnnotatedSchema ProtoBufAnnotation QuickstartSchema + = '[ 'AnnField "HelloRequest" "name" ('ProtoBufId 1) + , 'AnnField "HelloResponse" "message" ('ProtoBufId 1) + , 'AnnField "HiRequest" "number" ('ProtoBufId 1) ] + +main :: IO () +main = do + putStrLn "running quickstart application" + runGRpcApp 8080 quickstartServer diff --git a/src/Mu/GRpc/Server.hs b/src/Mu/GRpc/Server.hs new file mode 100644 --- /dev/null +++ b/src/Mu/GRpc/Server.hs @@ -0,0 +1,316 @@ +{-# language DataKinds #-} +{-# language FlexibleContexts #-} +{-# language FlexibleInstances #-} +{-# language GADTs #-} +{-# language MultiParamTypeClasses #-} +{-# language PolyKinds #-} +{-# language RankNTypes #-} +{-# language ScopedTypeVariables #-} +{-# language TypeApplications #-} +{-# language TypeOperators #-} +{-# language UndecidableInstances #-} +{-| +Description : Execute a Mu 'Server' using gRPC as transport layer + +This module allows you to server a Mu 'Server' +as a WAI 'Application' using gRPC as transport layer. + +The simples way is to use 'runGRpcApp', all other +variants provide more control over the settings. +-} +module Mu.GRpc.Server +( -- * Run a 'Server' directly + runGRpcApp, runGRpcAppTrans +, runGRpcAppSettings, Settings +, runGRpcAppTLS, TLSSettings + -- * Convert a 'Server' into a WAI application +, gRpcApp + -- * Raise errors as exceptions in IO +, raiseErrors, liftServerConduit +) where + +import Control.Concurrent.Async +import Control.Concurrent.STM (atomically) +import Control.Concurrent.STM.TMVar +import Control.Monad.Except +import Data.ByteString (ByteString) +import qualified Data.ByteString.Char8 as BS +import Data.Conduit +import Data.Conduit.TMChan +import Data.Kind +import Data.Proxy +import Network.GRPC.HTTP2.Encoding (gzip, uncompressed) +import Network.GRPC.HTTP2.Proto3Wire +import Network.GRPC.HTTP2.Types (GRPCStatus (..), GRPCStatusCode (..)) +import Network.GRPC.Server.Handlers +import Network.GRPC.Server.Wai as Wai +import Network.Wai (Application) +import Network.Wai.Handler.Warp (Port, Settings, run, runSettings) +import Network.Wai.Handler.WarpTLS (TLSSettings, runTLS) + +import Mu.Adapter.ProtoBuf.Via +import Mu.Rpc +import Mu.Schema +import Mu.Server + +-- | Run a Mu 'Server' on the given port. +runGRpcApp + :: ( KnownName name, KnownName (FindPackageName anns) + , GRpcMethodHandlers ServerErrorIO methods handlers ) + => Port + -> ServerT Maybe ('Service name anns methods) ServerErrorIO handlers + -> IO () +runGRpcApp port = runGRpcAppTrans port id + +-- | Run a Mu 'Server' on the given port. +runGRpcAppTrans + :: ( KnownName name, KnownName (FindPackageName anns) + , GRpcMethodHandlers m methods handlers ) + => Port + -> (forall a. m a -> ServerErrorIO a) + -> ServerT Maybe ('Service name anns methods) m handlers + -> IO () +runGRpcAppTrans port f svr = run port (gRpcAppTrans f svr) + +-- | Run a Mu 'Server' using the given 'Settings'. +-- +-- Go to 'Network.Wai.Handler.Warp' to declare 'Settings'. +runGRpcAppSettings + :: ( KnownName name, KnownName (FindPackageName anns) + , GRpcMethodHandlers m methods handlers ) + => Settings + -> (forall a. m a -> ServerErrorIO a) + -> ServerT Maybe ('Service name anns methods) m handlers + -> IO () +runGRpcAppSettings st f svr = runSettings st (gRpcAppTrans f svr) + +-- | Run a Mu 'Server' using the given 'TLSSettings' and 'Settings'. +-- +-- Go to 'Network.Wai.Handler.WarpTLS' to declare 'TLSSettings' +-- and to 'Network.Wai.Handler.Warp' to declare 'Settings'. +runGRpcAppTLS + :: ( KnownName name, KnownName (FindPackageName anns) + , GRpcMethodHandlers m methods handlers ) + => TLSSettings -> Settings + -> (forall a. m a -> ServerErrorIO a) + -> ServerT Maybe ('Service name anns methods) m handlers + -> IO () +runGRpcAppTLS tls st f svr = runTLS tls st (gRpcAppTrans f svr) + +-- | Turn a Mu 'Server' into a WAI 'Application'. +-- +-- These 'Application's can be later combined using, +-- for example, @wai-routes@, or you can add middleware +-- from @wai-extra@, among others. +gRpcApp + :: ( KnownName name, KnownName (FindPackageName anns) + , GRpcMethodHandlers ServerErrorIO methods handlers ) + => ServerT Maybe ('Service name anns methods) ServerErrorIO handlers + -> Application +gRpcApp = gRpcAppTrans id + +-- | Turn a Mu 'Server' into a WAI 'Application'. +-- +-- These 'Application's can be later combined using, +-- for example, @wai-routes@, or you can add middleware +-- from @wai-extra@, among others. +gRpcAppTrans + :: ( KnownName name, KnownName (FindPackageName anns) + , GRpcMethodHandlers m methods handlers ) + => (forall a. m a -> ServerErrorIO a) + -> ServerT Maybe ('Service name anns methods) m handlers + -> Application +gRpcAppTrans f svr = Wai.grpcApp [uncompressed, gzip] + (gRpcServiceHandlers f svr) + +gRpcServiceHandlers + :: forall name anns methods handlers m. + (KnownName name, KnownName (FindPackageName anns), GRpcMethodHandlers m methods handlers) + => (forall a. m a -> ServerErrorIO a) + -> ServerT Maybe ('Service name anns methods) m handlers + -> [ServiceHandler] +gRpcServiceHandlers f (Server svr) = gRpcMethodHandlers f packageName serviceName svr + where packageName = BS.pack (nameVal (Proxy @(FindPackageName anns))) + serviceName = BS.pack (nameVal (Proxy @name)) + +class GRpcMethodHandlers (m :: Type -> Type) (ms :: [Method mnm]) (hs :: [Type]) where + gRpcMethodHandlers :: (forall a. m a -> ServerErrorIO a) + -> ByteString -> ByteString + -> HandlersT Maybe ms m hs -> [ServiceHandler] + +instance GRpcMethodHandlers m '[] '[] where + gRpcMethodHandlers _ _ _ H0 = [] +instance (KnownName name, GRpcMethodHandler m args r h, GRpcMethodHandlers m rest hs) + => GRpcMethodHandlers m ('Method name anns args r ': rest) (h ': hs) where + gRpcMethodHandlers f p s (h :<|>: rest) + = gRpcMethodHandler f (Proxy @args) (Proxy @r) (RPC p s methodName) h + : gRpcMethodHandlers f p s rest + where methodName = BS.pack (nameVal (Proxy @name)) + +class GRpcMethodHandler m args r h where + gRpcMethodHandler :: (forall a. m a -> ServerErrorIO a) + -> Proxy args -> Proxy r -> RPC -> h -> ServiceHandler + +-- | Turns a 'Conduit' working on 'ServerErrorIO' +-- into any other base monad which supports 'IO', +-- by raising any error as an exception. +-- +-- This function is useful to interoperate with +-- libraries which generate 'Conduit's with other +-- base monads, such as @persistent@. +liftServerConduit + :: MonadIO m + => ConduitT a b ServerErrorIO r -> ConduitT a b m r +liftServerConduit = transPipe raiseErrors + +-- | Raises errors from 'ServerErrorIO' as exceptions +-- in a monad which supports 'IO'. +-- +-- This function is useful to interoperate with other +-- libraries which cannot handle the additional error +-- layer. In particular, with Conduit, as witnessed +-- by 'liftServerConduit'. +raiseErrors :: MonadIO m => ServerErrorIO a -> m a +raiseErrors h + = liftIO $ do + h' <- runExceptT h + case h' of + Right r -> return r + Left (ServerError code msg) + -> closeEarly $ GRPCStatus (serverErrorToGRpcError code) + (BS.pack msg) + where + serverErrorToGRpcError :: ServerErrorCode -> GRPCStatusCode + serverErrorToGRpcError Unknown = UNKNOWN + serverErrorToGRpcError Unavailable = UNAVAILABLE + serverErrorToGRpcError Unimplemented = UNIMPLEMENTED + serverErrorToGRpcError Unauthenticated = UNAUTHENTICATED + serverErrorToGRpcError Internal = INTERNAL + serverErrorToGRpcError NotFound = NOT_FOUND + serverErrorToGRpcError Invalid = INVALID_ARGUMENT + +instance GRpcMethodHandler m '[ ] 'RetNothing (m ()) where + gRpcMethodHandler f _ _ rpc h + = unary @_ @() @() rpc (\_ _ -> raiseErrors (f h)) + +instance (ToProtoBufTypeRef rref r) + => GRpcMethodHandler m '[ ] ('RetSingle rref) (m r) where + gRpcMethodHandler f _ _ rpc h + = unary @_ @() @(ViaToProtoBufTypeRef rref r) + rpc (\_ _ -> ViaToProtoBufTypeRef <$> raiseErrors (f h)) + +instance (ToProtoBufTypeRef rref r, MonadIO m) + => GRpcMethodHandler m '[ ] ('RetStream rref) + (ConduitT r Void m () -> m ()) where + gRpcMethodHandler f _ _ rpc h + = serverStream @_ @() @(ViaToProtoBufTypeRef rref r) rpc sstream + where sstream :: req -> () + -> IO ((), ServerStream (ViaToProtoBufTypeRef rref r) ()) + sstream _ _ = do + -- Variable to connect input and output + var <- newEmptyTMVarIO :: IO (TMVar (Maybe r)) + -- Start executing the handler + promise <- async (raiseErrors $ ViaToProtoBufTypeRef <$> f (h (toTMVarConduit var))) + -- Return the information + let readNext _ + = do nextOutput <- atomically $ takeTMVar var + case nextOutput of + Just o -> return $ Just ((), ViaToProtoBufTypeRef o) + Nothing -> do cancel promise + return Nothing + return ((), ServerStream readNext) + +instance (FromProtoBufTypeRef vref v) + => GRpcMethodHandler m '[ 'ArgSingle vref ] 'RetNothing (v -> m ()) where + gRpcMethodHandler f _ _ rpc h + = unary @_ @(ViaFromProtoBufTypeRef vref v) @() + rpc (\_ -> raiseErrors . f . h . unViaFromProtoBufTypeRef) + +instance (FromProtoBufTypeRef vref v, ToProtoBufTypeRef rref r) + => GRpcMethodHandler m '[ 'ArgSingle vref ] ('RetSingle rref) (v -> m r) where + gRpcMethodHandler f _ _ rpc h + = unary @_ @(ViaFromProtoBufTypeRef vref v) @(ViaToProtoBufTypeRef rref r) + rpc (\_ -> (ViaToProtoBufTypeRef <$>) . raiseErrors . f . h . unViaFromProtoBufTypeRef) + +instance (FromProtoBufTypeRef vref v, ToProtoBufTypeRef rref r, MonadIO m) + => GRpcMethodHandler m '[ 'ArgStream vref ] ('RetSingle rref) + (ConduitT () v m () -> m r) where + gRpcMethodHandler f _ _ rpc h + = clientStream @_ @(ViaFromProtoBufTypeRef vref v) @(ViaToProtoBufTypeRef rref r) + rpc cstream + where cstream :: req + -> IO ((), ClientStream (ViaFromProtoBufTypeRef vref v) + (ViaToProtoBufTypeRef rref r) ()) + cstream _ = do + -- Create a new TMChan + chan <- newTMChanIO :: IO (TMChan v) + let producer = sourceTMChan @m chan + -- Start executing the handler in another thread + promise <- async (raiseErrors $ ViaToProtoBufTypeRef <$> f (h producer)) + -- Build the actual handler + let cstreamHandler _ (ViaFromProtoBufTypeRef newInput) + = atomically (writeTMChan chan newInput) + cstreamFinalizer _ + = atomically (closeTMChan chan) >> wait promise + -- Return the information + return ((), ClientStream cstreamHandler cstreamFinalizer) + +instance (FromProtoBufTypeRef vref v, ToProtoBufTypeRef rref r, MonadIO m) + => GRpcMethodHandler m '[ 'ArgSingle vref ] ('RetStream rref) + (v -> ConduitT r Void m () -> m ()) where + gRpcMethodHandler f _ _ rpc h + = serverStream @_ @(ViaFromProtoBufTypeRef vref v) @(ViaToProtoBufTypeRef rref r) + rpc sstream + where sstream :: req -> ViaFromProtoBufTypeRef vref v + -> IO ((), ServerStream (ViaToProtoBufTypeRef rref r) ()) + sstream _ (ViaFromProtoBufTypeRef v) = do + -- Variable to connect input and output + var <- newEmptyTMVarIO :: IO (TMVar (Maybe r)) + -- Start executing the handler + promise <- async (raiseErrors $ ViaToProtoBufTypeRef <$> f (h v (toTMVarConduit var))) + -- Return the information + let readNext _ + = do nextOutput <- atomically $ takeTMVar var + case nextOutput of + Just o -> return $ Just ((), ViaToProtoBufTypeRef o) + Nothing -> do cancel promise + return Nothing + return ((), ServerStream readNext) + +instance (FromProtoBufTypeRef vref v, ToProtoBufTypeRef rref r, MonadIO m) + => GRpcMethodHandler m '[ 'ArgStream vref ] ('RetStream rref) + (ConduitT () v m () -> ConduitT r Void m () -> m ()) where + gRpcMethodHandler f _ _ rpc h + = generalStream @_ @(ViaFromProtoBufTypeRef vref v) @(ViaToProtoBufTypeRef rref r) + rpc bdstream + where bdstream :: req -> IO ( (), IncomingStream (ViaFromProtoBufTypeRef vref v) () + , (), OutgoingStream (ViaToProtoBufTypeRef rref r) () ) + bdstream _ = do + -- Create a new TMChan and a new variable + chan <- newTMChanIO :: IO (TMChan v) + let producer = sourceTMChan @m chan + var <- newEmptyTMVarIO :: IO (TMVar (Maybe r)) + -- Start executing the handler + promise <- async (raiseErrors $ f $ h producer (toTMVarConduit var)) + -- Build the actual handler + let cstreamHandler _ (ViaFromProtoBufTypeRef newInput) + = atomically (writeTMChan chan newInput) + cstreamFinalizer _ + = atomically (closeTMChan chan) >> wait promise + readNext _ + = do nextOutput <- atomically $ tryTakeTMVar var + case nextOutput of + Just (Just o) -> + return $ Just ((), ViaToProtoBufTypeRef o) + Just Nothing -> do + cancel promise + return Nothing + Nothing -> -- no new elements to output + readNext () + return ((), IncomingStream cstreamHandler cstreamFinalizer, (), OutgoingStream readNext) + +toTMVarConduit :: MonadIO m => TMVar (Maybe r) -> ConduitT r Void m () +toTMVarConduit var = do + x <- await + liftIO $ atomically $ putTMVar var x + toTMVarConduit var