gRPC-haskell/examples/tutorial/arithmetic.proto

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;
}