envoy: Initial changes

internal/controlplane/server.go

@@ -0,0 +1,139 @@
+package controlplane
+
+import (
+	"context"
+	"net"
+	"net/http"
+	"sync/atomic"
+	"time"
+
+	"github.com/gorilla/mux"
+	"golang.org/x/sync/errgroup"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/reflection"
+
+	"github.com/pomerium/pomerium/config"
+	"github.com/pomerium/pomerium/internal/log"
+)
+
+type versionedOptions struct {
+	config.Options
+	version int64
+}
+
+// A Server is the control-plane gRPC and HTTP servers.
+type Server struct {
+	GRPCListener net.Listener
+	GRPCServer   *grpc.Server
+	HTTPListener net.Listener
+	HTTPRouter   *mux.Router
+
+	currentConfig atomic.Value
+	configUpdated chan struct{}
+}
+
+// NewServer creates a new Server. Listener ports are chosen by the OS.
+func NewServer() (*Server, error) {
+	srv := &Server{
+		configUpdated: make(chan struct{}, 1),
+	}
+	srv.currentConfig.Store(versionedOptions{})
+
+	var err error
+
+	// setup gRPC
+	srv.GRPCListener, err = net.Listen("tcp4", "127.0.0.1:0")
+	if err != nil {
+		return nil, err
+	}
+	srv.GRPCServer = grpc.NewServer()
+	reflection.Register(srv.GRPCServer)
+	srv.registerXDSHandlers()
+	srv.registerAccessLogHandlers()
+
+	// setup HTTP
+	srv.HTTPListener, err = net.Listen("tcp4", "127.0.0.1:0")
+	if err != nil {
+		_ = srv.GRPCListener.Close()
+		return nil, err
+	}
+	srv.HTTPRouter = mux.NewRouter()
+	srv.addHTTPMiddleware()
+
+	return srv, nil
+}
+
+// Run runs the control-plane gRPC and HTTP servers.
+func (srv *Server) Run(ctx context.Context) error {
+	eg, ctx := errgroup.WithContext(ctx)
+
+	// start the gRPC server
+	eg.Go(func() error {
+		log.Info().Str("addr", srv.GRPCListener.Addr().String()).Msg("starting control-plane gRPC server")
+		return srv.GRPCServer.Serve(srv.GRPCListener)
+	})
+
+	// gracefully stop the gRPC server on context cancellation
+	eg.Go(func() error {
+		<-ctx.Done()
+
+		ctx, cancel := context.WithCancel(ctx)
+		ctx, cleanup := context.WithTimeout(ctx, time.Second*5)
+		defer cleanup()
+
+		go func() {
+			srv.GRPCServer.GracefulStop()
+			cancel()
+		}()
+
+		go func() {
+			<-ctx.Done()
+			srv.GRPCServer.Stop()
+			cancel()
+		}()
+
+		<-ctx.Done()
+
+		return nil
+	})
+
+	hsrv := (&http.Server{
+		BaseContext: func(li net.Listener) context.Context {
+			return ctx
+		},
+		Handler: srv.HTTPRouter,
+	})
+
+	// start the HTTP server
+	eg.Go(func() error {
+		log.Info().Str("addr", srv.HTTPListener.Addr().String()).Msg("starting control-plane HTTP server")
+		return hsrv.Serve(srv.HTTPListener)
+	})
+
+	// gracefully stop the HTTP server on context cancellation
+	eg.Go(func() error {
+		<-ctx.Done()
+
+		ctx, cleanup := context.WithTimeout(ctx, time.Second*5)
+		defer cleanup()
+
+		return hsrv.Shutdown(ctx)
+	})
+
+	return eg.Wait()
+}
+
+// UpdateOptions updates the pomerium config options.
+func (srv *Server) UpdateOptions(options config.Options) error {
+	select {
+	case <-srv.configUpdated:
+	default:
+	}
+	prev := srv.currentConfig.Load().(versionedOptions)
+	srv.currentConfig.Store(versionedOptions{
+		Options: options,
+		version: prev.version + 1,
+	})
+	srv.configUpdated <- struct{}{}
+	return nil
+}