wireform-grpc

wireform-grpc is a native Haskell implementation of gRPC. gRPC is the standard RPC layer for microservices that already speak Protocol Buffers. Use this package when you need a pure-Haskell client or server with unary and streaming call patterns, without binding to the C++ gRPC core library.

The library is vendored from grapesy by Edsko de Vries (Well-Typed) and integrated into the wireform monorepo so service codegen targets a known in-tree binding.

Key features

• Client and server under Network.GRPC.Client and Network.GRPC.Server
• Unary and streaming RPCs: server streaming, client streaming, and bidirectional streaming
• HTTP/2 transport via the in-tree wireform-http2 engine
• TLS with certificate store helpers
• Message compression negotiation
• Protobuf and JSON codecs through Network.GRPC.Common.Protobuf and Network.GRPC.Common.JSON
• OpenTelemetry instrumentation via Network.GRPC.Client.Otel and Network.GRPC.Server.Otel

Basic usage

A minimal unary client call. Protobuf service types come from wireform-proto codegen or a Proto.TH.loadProto splice:

import           Network.GRPC.Client
import qualified Network.GRPC.Client.StreamType.IO as IO
import           Network.GRPC.Common
import           Network.GRPC.Common.Protobuf

import qualified Routeguide.Service.RouteGuide as RG

main :: IO ()
main = do
  let server = ServerInsecure (Address "localhost" 50051 Nothing)
  withConnection def server $ \conn -> do
    feature <-
      IO.nonStreaming
        conn
        (rpc @(Protobuf RG.RouteGuide "GetFeature"))
        (defMessage & RG.point .~ pt 408000000 (-743000000))
    print feature
  where
    pt lat lon =
      defMessage & RG.latitude .~ lat & RG.longitude .~ lon

For server-side handlers, use Network.GRPC.Server.Run with handlers constructed from Network.GRPC.Server.StreamType:

import           Network.GRPC.Server.Run
import           Network.GRPC.Server.StreamType

runGuideServer :: IO ()
runGuideServer =
  runServerWithHandlers def config handlers
  where
    config =
      ServerConfig
        { serverInsecure = Just (InsecureConfig (Just "0.0.0.0") 50051)
        , serverSecure   = Nothing
        }
    handlers =
      [ fromMethod (mkNonStreaming handleGetFeature)
      ]

Wrap calls with Network.GRPC.Client.Otel.withTracedRPC when you need distributed tracing spans around RPC latency.

Notable modules

Module	Purpose
Network.GRPC.Client	Connection management, withConnection, withRPC
Network.GRPC.Client.StreamType.IO	Unary and streaming client handlers
Network.GRPC.Server	Server handler registration and call dispatch
Network.GRPC.Server.Run	Server lifecycle and listener setup
Network.GRPC.Common.Protobuf	Protobuf codec integration with wireform-proto
Network.GRPC.Common.Compression	Compression negotiation
Network.GRPC.Client.Otel / Network.GRPC.Server.Otel	OpenTelemetry hooks
Network.GRPC.Util.TLS	Certificate store and TLS helpers

Module naming

This package follows grapesy’s Network.GRPC.* module layout rather than wireform’s <Format>.* convention, so existing grapesy imports continue to work after the vendored migration.