GRPC

GRPC

  • Define a Service using Protocol Buffers
  • Generate Client and Server Stubs in a variety of languages
  • HTTP/2 brings capabilities like bidirectional streaming

INTERFACE DEFINITION LANGUAGE (IDL)

message HelloRequest {
  string greeting = 1;
}

message HelloResponse {
  string reply = 1;
}

service HelloService {
  rpc SayHello(HelloRequest) returns (HelloResponse);
}

STREAMING

message Demo {
   string Value = 1;
}

service DemoService {

  rpc Hello(Demo) returns (Demo);

  rpc Download(Demo) returns (stream Demo);

  rpc Upload(stream Demo) returns (Demo);

  rpc BestOfBoth(stream Demo) returns (stream Demo);

}

GO Client

func main() {
    grpcAddr := "localhost:12345"
    conn, err := grpc.Dial(grpcAddr)
    if err != nil {
        log.Fatalf("Dial(%s) = %v", grpcAddr, err)
    }
    client := NewDemoServiceClient(conn)
    msg := &Demo{"hello world"}
    reply, err := client.Hello(context.Background(), msg)
    if err != nil {
        log.Fatalf("UnaryCall(%#v) failed with %v", msg, err)
    }
    println("received message " + reply.Value)
}

what is context: blog.golang.org/context

GO SErver

type server struct{}

func (this *server) Hello(c context.Context, msg *Demo) 
    (*Demo, error) {
	msg.Value = "Allo" + msg.Value
	return msg, nil
}

func main() {
	lis, err := net.Listen("tcp", "localhost:12345")
	if err != nil {
		log.Fatalf("Failed to listen: %v", err)
	}
	grpcServer := grpc.NewServer()
	RegisterDemoServiceServer(grpcServer, &server{})
	grpcServer.Serve(lis)
}

TCP

LENGTH DELIMITED

13025 ns/op

19130 ns/op

19885 ns/op

GRPC

11563 ns/op

23612 ns/op

21062 ns/op

PRELIMINARY SPEED

GOlang/protobuf

12460 ns/op

15972 ns/op

20603 ns/op

GOGO/protobuf

11105 ns/op

12332 ns/op

13536 ns/op

PRELIMINARY SPEED

REST HATEAOS

  • Stateless
  • Explorable API
  • Curlable/Hackable URLs
  • There is lots of technology to build on, including caching servers.   No need to roll your own.

GRPC

  • Stateful
  • Follow the types
  • I don't know yet
  • Alpha

REST HATEAOS

  • No standard IDL
  • Streaming is a hack
  • dynamic
  • If GRPC did NOT exist I was about to use it.

GRPC

  • IDL
  • Streaming
  • static
  • Tools are emerging at a rapid pace

JSON/REST ON GRPC

gRPC GATEWAY

import "github.com/gengo/grpc-gateway/options/options.proto";

message Demo {
    string value = 1;
}

service DemoService {
    rpc Hello(Demo) returns (Demo) {
        
option (gengo.grpc.gateway.ApiMethodOptions.api_options) = {
    path: "/v1/demo/hello"
    method: "POST"
}

    }
}

ProtoType GUI for GRPC

LETMEGRPC

message Allo {
	string Name = 1;
	int64 Age = 2;
	string Country = 3;
	bool Spy = 4;
}

service OnionSeller {
	rpc OnlyOnce(Allo) 
            returns (Allo);
}

DEMO

COMPLEX STRUCTURES

DEMO

LETMETESTSERVER

cd $GOPATH/src/github.com/gogo/letmegrpc/letmetestserver/serve

LETMEGRPC -PORT=8080 -ADDR=localhost:12345 Serve.proto

DEMO

Integrated

DEMO

CUstomization

CONCLUSION

  • Easy
  • Fast
  • Cross Language
  • API
  • Alpha
  • Tools are being rapidly developed,
  • Because its easy

GRPC

By Walter Schulze

GRPC

  • 626
Loading comments...

More from Walter Schulze