echoserver

README

echoserver

Simple gRPC based echoserver, which returns a string containing whatever the client sends in the request.

Build

This repo contains a Makefile and a Dockerfile, all the dependencies are added to the Dockerfile.

To build gRPC server run the following command

make build

This command will generate a Docker image called echoserver, this image contains both the server and the test client library to test the server.

Usage

To run the echoserver in a container use the following commands. Name the Docker container server, this way when the client container is started it can run the network namespace as server container.

Run in Server mode

docker run -d --rm --name=server echoserver /bin/server

Run in test client mode

docker run --rm --net=container:server echoserver /bin/client -msg=hi

Testing

To run the complete test suite including unit tests and integrations tests

make test

Example

Server mode

root@ubuntu:/# docker run -ti --rm --name=server echoserver /bin/server
2019/06/03 04:45:40 Receive message hi

test client mode

root@ubuntu:/# docker run --rm --net=container:server echoserver /bin/client -msg=hi
2019/06/03 04:45:40 Response from server: hi

Config flags

Server

root@ubuntu:/# docker run -ti --rm --name=server echoserver /bin/server -help
Usage of /bin/server:
  -port int
        gRPC server port (default 8080)

test client

root@ubuntu:/# docker run --rm --net=container:server echoserver /bin/client -help
Usage of /bin/client:
  -msg string
        Message to be sent to the server (default "hello")
  -port int
        gRPC server port (default 8080)

Updating server protobuf API

Update the server API in api/api.proto file, this will generate the server and client gRPC libraries

Install protoc

apt-get install unzip && \
wget https://github.com/protocolbuffers/protobuf/releases/download/v3.8.0/protoc-3.8.0-linux-x86_64.zip && \
unzip protoc-3.8.0-linux-x86_64.zip -d /tmp/ && mv /tmp/bin/protoc /usr/bin/

Install protoc-gen-go plugin

go get -u github.com/golang/protobuf/protoc-gen-go

Note: Make sure $PATH on the host contains $GOPATH/bin, else do export PATH=$PATH:$GOPATH/bin/

Once, you have both protoc and protoc-gen-go installed, run the following command to generate server and client stub package in api/api.pb.go

protoc -I api/ -I${GOPATH}/src --go_out=plugins=grpc:api api/api.proto