configcenter/cmd/server/main.go

package main

import (
	"context"
	"errors"
	"flag"
	"fmt"
	"log/slog"
	"net"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"

	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials"
	"google.golang.org/grpc/health"
	grpc_health_v1 "google.golang.org/grpc/health/grpc_health_v1"

	"github.com/longpeng/configcenter/internal/api/grpcapi"
	"github.com/longpeng/configcenter/internal/api/httpapi"
	"github.com/longpeng/configcenter/internal/auth"
	"github.com/longpeng/configcenter/internal/config"
	"github.com/longpeng/configcenter/internal/metrics"
	"github.com/longpeng/configcenter/internal/outbox"
	runtimepkg "github.com/longpeng/configcenter/internal/runtime"
	etcdstore "github.com/longpeng/configcenter/internal/runtime/etcd"
	memoryruntime "github.com/longpeng/configcenter/internal/runtime/memory"
	storepkg "github.com/longpeng/configcenter/internal/store"
	memory_store "github.com/longpeng/configcenter/internal/store/memory"
	postgres_store "github.com/longpeng/configcenter/internal/store/postgres"
	"github.com/longpeng/configcenter/internal/watch"
)

var (
	version   = "dev"
	commit    = "unknown"
	buildDate = "unknown"
)

func main() {
	migrateOnly := flag.Bool("migrate-only", false, "apply database migrations and exit")
	showVersion := flag.Bool("version", false, "print build version and exit")
	flag.Parse()
	if *showVersion {
		fmt.Printf("configcenter %s commit=%s built=%s\n", version, commit, buildDate)
		return
	}

	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{Level: slog.LevelInfo}))
	logger.Info("starting config center", "version", version, "commit", commit, "buildDate", buildDate)
	cfg := config.Load()
	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
	defer stop()

	repository, err := openStore(ctx, cfg, logger)
	if err != nil {
		logger.Error("open control-plane store", "error", err)
		os.Exit(1)
	}
	defer repository.Close()
	if *migrateOnly {
		logger.Info("database migrations applied")
		return
	}
	authorizer, err := auth.New(repository, cfg.AuthEnabled, cfg.JWTSecret, cfg.JWTTTL)
	if err != nil {
		logger.Error("initialize authentication", "error", err)
		os.Exit(1)
	}
	if err := authorizer.Bootstrap(ctx, cfg.BootstrapAdminUsername, cfg.BootstrapAdminPassword, cfg.BootstrapAdminDisplayName); err != nil {
		logger.Error("bootstrap administrator", "error", err)
		os.Exit(1)
	}

	runtimeStore, err := openRuntime(cfg, logger)
	if err != nil {
		logger.Error("open runtime store", "error", err)
		os.Exit(1)
	}
	defer runtimeStore.Close() //nolint:errcheck

	hub := watch.New(ctx, runtimeStore)
	collector := metrics.New()
	worker := outbox.New(repository, runtimeStore, cfg.OutboxInterval, cfg.OutboxBatchSize, cfg.OutboxMaxRetry, collector, logger)
	go worker.Run(ctx)

	api := httpapi.New(repository, runtimeStore, hub, authorizer, collector, cfg.AllowedOrigins, logger)
	httpServer := &http.Server{
		Addr:              cfg.HTTPAddr,
		Handler:           api.Handler(),
		ReadHeaderTimeout: 5 * time.Second,
		ReadTimeout:       15 * time.Second,
		IdleTimeout:       60 * time.Second,
	}
	grpcAPI := grpcapi.New(repository, runtimeStore, hub, authorizer, collector, logger)
	grpcOptions, err := grpcOptions(cfg, grpcAPI)
	if err != nil {
		logger.Error("configure grpc server", "error", err)
		os.Exit(1)
	}
	grpcServer := grpc.NewServer(grpcOptions...)
	grpcAPI.Register(grpcServer)
	healthServer := health.NewServer()
	grpc_health_v1.RegisterHealthServer(grpcServer, healthServer)
	healthServer.SetServingStatus("", grpc_health_v1.HealthCheckResponse_SERVING)
	grpcListener, err := (&net.ListenConfig{}).Listen(ctx, "tcp", cfg.GRPCAddr)
	if err != nil {
		logger.Error("listen grpc", "address", cfg.GRPCAddr, "error", err)
		os.Exit(1)
	}

	serverErrors := make(chan error, 2)
	go func() {
		logger.Info("config center http listening", "address", cfg.HTTPAddr)
		serverErrors <- httpServer.ListenAndServe()
	}()
	go func() {
		logger.Info("config center grpc listening", "address", cfg.GRPCAddr, "tls", cfg.GRPCTLSCertFile != "")
		serverErrors <- grpcServer.Serve(grpcListener)
	}()

	select {
	case <-ctx.Done():
		logger.Info("shutting down config center")
	case err := <-serverErrors:
		if err != nil && !errors.Is(err, http.ErrServerClosed) && !errors.Is(err, grpc.ErrServerStopped) {
			logger.Error("server stopped", "error", err)
		}
	}
	stop()

	shutdownCtx, cancel := context.WithTimeout(context.Background(), cfg.ShutdownTimeout)
	defer cancel()
	healthServer.Shutdown()
	if err := httpServer.Shutdown(shutdownCtx); err != nil {
		logger.Error("graceful shutdown", "error", err)
	}
	grpcStopped := make(chan struct{})
	go func() {
		grpcServer.GracefulStop()
		close(grpcStopped)
	}()
	select {
	case <-grpcStopped:
	case <-shutdownCtx.Done():
		grpcServer.Stop()
	}
}

func grpcOptions(cfg config.Config, api *grpcapi.Server) ([]grpc.ServerOption, error) {
	options := []grpc.ServerOption{
		grpc.UnaryInterceptor(api.UnaryInterceptor),
		grpc.StreamInterceptor(api.StreamInterceptor),
	}
	if (cfg.GRPCTLSCertFile == "") != (cfg.GRPCTLSKeyFile == "") {
		return nil, fmt.Errorf("GRPC_TLS_CERT_FILE and GRPC_TLS_KEY_FILE must be configured together")
	}
	if cfg.GRPCTLSCertFile != "" {
		transportCredentials, err := credentials.NewServerTLSFromFile(cfg.GRPCTLSCertFile, cfg.GRPCTLSKeyFile)
		if err != nil {
			return nil, fmt.Errorf("load grpc TLS certificate: %w", err)
		}
		options = append(options, grpc.Creds(transportCredentials))
	}
	return options, nil
}

func openStore(ctx context.Context, cfg config.Config, logger *slog.Logger) (storepkg.Store, error) {
	if cfg.DatabaseURL == "" {
		logger.Warn("DATABASE_URL is empty; using the in-memory control-plane store")
		return memory_store.New(true), nil
	}
	repository, err := postgres_store.Open(ctx, cfg.DatabaseURL)
	if err != nil {
		return nil, err
	}
	if err := repository.Migrate(ctx); err != nil {
		repository.Close()
		return nil, err
	}
	return repository, nil
}

func openRuntime(cfg config.Config, logger *slog.Logger) (runtimepkg.Store, error) {
	if len(cfg.EtcdEndpoints) == 0 {
		logger.Warn("ETCD_ENDPOINTS is empty; using the in-memory runtime store")
		return memoryruntime.New(), nil
	}
	tlsConfig, err := etcdstore.NewTLSConfig(etcdstore.TLSOptions{
		CAFile:     cfg.EtcdTLSCAFile,
		CertFile:   cfg.EtcdTLSCertFile,
		KeyFile:    cfg.EtcdTLSKeyFile,
		ServerName: cfg.EtcdTLSServerName,
	})
	if err != nil {
		return nil, err
	}
	return etcdstore.Open(cfg.EtcdEndpoints, cfg.EtcdDialTimeout, tlsConfig)
}