Go Multi-Server

cmd_api_main.go

package main

import (
	"net/http"
	"os"
	"os/signal"
	"syscall"

	"github.com/orbservability/io/pkg/server"
	pb "github.com/orbservability/schemas/v1"
	"github.com/prometheus/client_golang/prometheus/promhttp"
	"github.com/rs/zerolog/log"
	"orbservability.com/ingestion-api/pkg/eventgateway"
)

func main() {
	// Error channel for server errors
	errChan := make(chan error, 2)

	// Map HTTP routes to handlers, and serve HTTP
	httpServer := server.ServeHTTP(errChan, map[string]http.Handler{"/metrics": promhttp.Handler()})

	// Initialize gRPC services, and serve gRPC
	eventGateway := &eventgateway.ServiceHandler{}
	grpcServer := server.ServeGRPC(errChan, []server.ServiceRegistrar{eventGateway})

	// Set up signal handling for graceful shutdown, and wait for a termination signal
	sigChan := make(chan os.Signal, 1)
	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)

	// Block until a signal is received
	select {
	case <-sigChan:
		log.Warn().Msg("Application shutting down")

		server.ShutdownGRPC(grpcServer)
		server.ShutdownHTTP(httpServer)
	case err := <-errChan:
		log.Fatal().Err(err).Msg("Server error")
	}
}

pkg_eventgateway_handler.go

package eventgateway

import (
	"reflect"

	pb "github.com/orbservability/schemas/v1"
	"google.golang.org/grpc"

	"github.com/rs/zerolog/log"
)

type ServiceHandler struct {
	pb.UnimplementedEventGatewayServiceServer
}

func (s *ServiceHandler) RegisterWithServer(grpcServer *grpc.Server) {
	pb.RegisterEventGatewayServiceServer(grpcServer, s)
}

func (s *ServiceHandler) StreamEvents(stream pb.EventGatewayService_StreamEventsServer) error {
	for {
		msg, err := stream.Recv()
		if err != nil {
			return err
		}

		log.Debug().
			Stringer("msg", msg).
			Stringer("type", reflect.TypeOf(msg)).
			Msg("Message received")
	}
}