Greeter service snippets

example1.kt

val person = Person.newBuilder()
            .setName("Hello Kitty")
            .setAddress(
                    Address.newBuilder()
                            .setNumber(123)
                            .setStreet("Hello Kitty Street")
                            .setPostcode("N304SD")
                            .build())
            .build()

greeter.proto

syntax = "proto3";

option java_multiple_files = true;
option java_package = "io.grpc.examples.helloworld";
option java_outer_classname = "HelloWorldProto";
option objc_class_prefix = "HLW";

package helloworld;

// The greeting service definition.
service Greeter {
    // Sends a greeting
    rpc SayHello (HelloRequest) returns (HelloReply);
}

// The request message containing the user's name.
message HelloRequest {
    string name = 1;
}

// The response message containing the greetings
message HelloReply {
    string message = 1;
}

greeter0.kt

class GreeterServiceImpl : GreeterGrpc.GreeterImplBase() {
    override fun sayHello(request: HelloRequest, responseObserver: StreamObserver<HelloReply>) {
        if (request.name.contains("voldemort")) {
            throw Status.INVALID_ARGUMENT
                .withDescription("You are not welcome here ${request.name}")
                .asRuntimeException()
        }

        // Notice the painful object builder
        val reply = HelloReply.newBuilder().apply {
            message = "Hello ${request.name}"
        }.build()

        responseObserver.onNext(reply)
        responseObserver.onCompleted()
    }
}

greeter2.kt

class BetterGreeterServiceImpl : Greeter {
    override fun sayHello(request: HelloRequest): HelloReply {
        if (request.name.contains("voldemort")) {
            throw Status.INVALID_ARGUMENT
                .withDescription("You are not welcome here ${request.name}")
                .asRuntimeException()
        }

        return newHelloReply {
            message = "Hello ${request.name}"
        }
    }
}

person.proto

syntax = "proto3";

message Person {
    string name = 1;
    Address address = 2;
}

message Address {
    int32 number = 1;
    string street = 2;
    string postCode = 3;
}