server.go

// Copyright 2018 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package main

import (
	"context"
	"flag"
	"fmt"
	"net"
	"os"

	pb "github.com/triplewy/microservices-demo/src/emailservice/genproto"
	healthpb "google.golang.org/grpc/health/grpc_health_v1"

	"go.uber.org/zap"
	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

var (
	port string

	zLogger *zap.Logger
	sugar   *zap.SugaredLogger
)

func init() {
	port = "8080"

	if os.Getenv("PORT") != "" {
		port = os.Getenv("PORT")
	}

	zLogger, _ = zap.NewProduction()
	sugar = zLogger.Sugar()
}

func main() {
	flag.Parse()

	defer zLogger.Sync()

	sugar.Infof("starting grpc server at :%s", port)
	run(port)
	select {}
}

func run(port string) string {
	l, err := net.Listen("tcp", fmt.Sprintf(":%s", port))
	if err != nil {
		sugar.Fatal(err)
	}
	srv := grpc.NewServer()
	svc := &email{}
	pb.RegisterEmailServiceServer(srv, svc)
	healthpb.RegisterHealthServer(srv, svc)
	go srv.Serve(l)
	return l.Addr().String()
}

type email struct{}

func (e *email) SendOrderConfirmation(ctx context.Context, req *pb.SendOrderConfirmationRequest) (*pb.Empty, error) {
	sugar.Infof("A request to send order confirmation email to %v has been received.", req.GetEmail())
	return &pb.Empty{}, nil
}

func (e *email) Check(ctx context.Context, req *healthpb.HealthCheckRequest) (*healthpb.HealthCheckResponse, error) {
	return &healthpb.HealthCheckResponse{Status: healthpb.HealthCheckResponse_SERVING}, nil
}

func (e *email) Watch(req *healthpb.HealthCheckRequest, ws healthpb.Health_WatchServer) error {
	return status.Errorf(codes.Unimplemented, "health check via Watch not implemented")
}