grpc-envoy-docker

Sample project showing how to expose a gRPC service as an HTTP/JSON api using Envoy.

About envoy

The Envoy filter allows a RESTful JSON API client to send requests to Envoy over HTTP and get proxied to a gRPC service. Envoy proxy documentation

Requirements

• Docker
• protoc

How to start

Compile the proto

Before running the application we have to compile the proto file user_management.proto.
To do that run the script generate_api.sh located under the root.
Make sure you have installed protoc on your machine, otherwise check the documentation https://grpc.io/docs/protoc-installation/ .

Run the application

Start docker containers : docker-compose up
Stop docker containers : docker-compose down

Testing the REST API

Now you should have the gRPC service running and serving at 9091 port, and envoy listening at port 9090.
To test the application you can use Postman, curl or any other http client to make http request at port 9090.

 curl -X POST
   http://localhost:9090/api/v1/users
   -H 'Content-Type: application/json'
   -d '{
     "first_name": "Federico",
     "last_name": "La Penna"
    }'

Testing the gRPC API

Keep in my mind the port 9091 isn't mapped in the docker-compose.yaml, so you won't be able to hit the gRPC server from a network outside the Docker one.
To hit the service with gRPC request make sure the port is mapped in the docker-compose.yaml.

services:
  grpcservice:
    build:
      context: .
      dockerfile: Dockerfile-service
    expose:
      - "9091"

to

services:
  grpcservice:
    build:
      context: .
      dockerfile: Dockerfile-service
    ports:
      - "9091:9091"

Diagram

Authors

• Federico La Penna