ctappy / grpc-go-tutorial

Simple tutorial on gRPC

Simple tutorial, based on the lessons from Stephane Maarek: gRPC [Golang] Master Class, on gRPC which covers the super basics on how to setup a gRPC client/server using golang

gRPC concepts

unary calls - one message to server and one message response to client https://grpc.io/docs/guides/concepts.html#unary-rpc

server streaming - one message to server and streaming response back to client https://grpc.io/docs/guides/concepts.html#server-streaming-rpc

client streaming - streaming message to server and one message response back to client https://grpc.io/docs/guides/concepts.html#client-streaming-rpc

bi-directional streaming - streaming to server and streaming to client https://grpc.io/docs/guides/concepts.html#bidirectional-streaming-rpc

Install this repo with grpc/proto

Download compiled protoc and add to your PATH

https://github.com/protocolbuffers/protobuf/releases

go get github.com/ctaperts/grpc-go-tutorial
go get -u google.golang.org/grpc
go get -u github.com/golang/protobuf/protoc-gen-go
cd $GOPATH/src/github.com/ctaperts

Steps to generate setup

create the protobuff golang setup

./generate.sh

will generate greet/greetpb/greet.pb.go view the comments in the ./greet/greetpb/greet.proto and find them again in the generated file

greet/greetpb/greet.pb.go will be generated with all of the functions from the ./greet/greetpb/greet.proto and additional functions used in the server/client. For example in ./greet/greetpb/greet.proto the line

    rpc GreetWithDeadline(GreetWithDeadlineRequest) returns (GreetWithDeadlineResponse) {};

will create a function GreetWithDeadline used in server.go and in the client.go file. view the GreetServiceClient interface and the GreetServiceServer interface for more info.

Run

The following is a simple unary call that will timeout on the second request because of the deadline/timeout

run with one terminal running

go run greet/greet_server/server.go

and in another terminal run

go run greet/greet_client/client.go