prysm-pulse/beacon-chain/rpc/service.go

// Package rpc defines the services that the beacon-chain uses to communicate via gRPC.
package rpc

import (
	"context"
	"fmt"
	"math/rand"
	"net"
	"os"

	middleware "github.com/grpc-ecosystem/go-grpc-middleware"
	recovery "github.com/grpc-ecosystem/go-grpc-middleware/recovery"
	grpc_opentracing "github.com/grpc-ecosystem/go-grpc-middleware/tracing/opentracing"
	grpc_prometheus "github.com/grpc-ecosystem/go-grpc-prometheus"
	ethpb "github.com/prysmaticlabs/ethereumapis/eth/v1alpha1"
	"github.com/prysmaticlabs/prysm/beacon-chain/blockchain"
	"github.com/prysmaticlabs/prysm/beacon-chain/cache"
	"github.com/prysmaticlabs/prysm/beacon-chain/cache/depositcache"
	opfeed "github.com/prysmaticlabs/prysm/beacon-chain/core/feed/operation"
	statefeed "github.com/prysmaticlabs/prysm/beacon-chain/core/feed/state"
	"github.com/prysmaticlabs/prysm/beacon-chain/db"
	"github.com/prysmaticlabs/prysm/beacon-chain/operations/attestations"
	"github.com/prysmaticlabs/prysm/beacon-chain/operations/voluntaryexits"
	"github.com/prysmaticlabs/prysm/beacon-chain/p2p"
	"github.com/prysmaticlabs/prysm/beacon-chain/powchain"
	"github.com/prysmaticlabs/prysm/beacon-chain/rpc/aggregator"
	"github.com/prysmaticlabs/prysm/beacon-chain/rpc/beacon"
	"github.com/prysmaticlabs/prysm/beacon-chain/rpc/node"
	"github.com/prysmaticlabs/prysm/beacon-chain/rpc/validator"
	"github.com/prysmaticlabs/prysm/beacon-chain/sync"
	pbp2p "github.com/prysmaticlabs/prysm/proto/beacon/p2p/v1"
	pb "github.com/prysmaticlabs/prysm/proto/beacon/rpc/v1"
	slashpb "github.com/prysmaticlabs/prysm/proto/slashing"
	"github.com/prysmaticlabs/prysm/shared/featureconfig"
	"github.com/prysmaticlabs/prysm/shared/params"
	"github.com/prysmaticlabs/prysm/shared/slotutil"
	"github.com/prysmaticlabs/prysm/shared/traceutil"
	"github.com/sirupsen/logrus"
	"go.opencensus.io/plugin/ocgrpc"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials"
	"google.golang.org/grpc/reflection"
)

var log logrus.FieldLogger

func init() {
	log = logrus.WithField("prefix", "rpc")
	rand.Seed(int64(os.Getpid()))
}

// Service defining an RPC server for a beacon node.
type Service struct {
	ctx                    context.Context
	cancel                 context.CancelFunc
	beaconDB               db.HeadAccessDatabase
	headFetcher            blockchain.HeadFetcher
	forkFetcher            blockchain.ForkFetcher
	finalizationFetcher    blockchain.FinalizationFetcher
	participationFetcher   blockchain.ParticipationFetcher
	genesisTimeFetcher     blockchain.GenesisTimeFetcher
	attestationReceiver    blockchain.AttestationReceiver
	blockReceiver          blockchain.BlockReceiver
	powChainService        powchain.Chain
	chainStartFetcher      powchain.ChainStartFetcher
	mockEth1Votes          bool
	attestationsPool       attestations.Pool
	exitPool               *voluntaryexits.Pool
	syncService            sync.Checker
	host                   string
	port                   string
	listener               net.Listener
	withCert               string
	withKey                string
	grpcServer             *grpc.Server
	canonicalStateChan     chan *pbp2p.BeaconState
	incomingAttestation    chan *ethpb.Attestation
	credentialError        error
	p2p                    p2p.Broadcaster
	peersFetcher           p2p.PeersProvider
	depositFetcher         depositcache.DepositFetcher
	pendingDepositFetcher  depositcache.PendingDepositsFetcher
	stateNotifier          statefeed.Notifier
	operationNotifier      opfeed.Notifier
	slasherConn            *grpc.ClientConn
	slasherProvider        string
	slasherCert            string
	slasherCredentialError error
	slasherClient          slashpb.SlasherClient
}

// Config options for the beacon node RPC server.
type Config struct {
	Host                  string
	Port                  string
	CertFlag              string
	KeyFlag               string
	BeaconDB              db.HeadAccessDatabase
	HeadFetcher           blockchain.HeadFetcher
	ForkFetcher           blockchain.ForkFetcher
	FinalizationFetcher   blockchain.FinalizationFetcher
	ParticipationFetcher  blockchain.ParticipationFetcher
	AttestationReceiver   blockchain.AttestationReceiver
	BlockReceiver         blockchain.BlockReceiver
	POWChainService       powchain.Chain
	ChainStartFetcher     powchain.ChainStartFetcher
	GenesisTimeFetcher    blockchain.GenesisTimeFetcher
	MockEth1Votes         bool
	AttestationsPool      attestations.Pool
	ExitPool              *voluntaryexits.Pool
	SyncService           sync.Checker
	Broadcaster           p2p.Broadcaster
	PeersFetcher          p2p.PeersProvider
	DepositFetcher        depositcache.DepositFetcher
	PendingDepositFetcher depositcache.PendingDepositsFetcher
	SlasherProvider       string
	SlasherCert           string
	StateNotifier         statefeed.Notifier
	OperationNotifier     opfeed.Notifier
}

// NewService instantiates a new RPC service instance that will
// be registered into a running beacon node.
func NewService(ctx context.Context, cfg *Config) *Service {
	ctx, cancel := context.WithCancel(ctx)
	return &Service{
		ctx:                   ctx,
		cancel:                cancel,
		beaconDB:              cfg.BeaconDB,
		headFetcher:           cfg.HeadFetcher,
		forkFetcher:           cfg.ForkFetcher,
		finalizationFetcher:   cfg.FinalizationFetcher,
		participationFetcher:  cfg.ParticipationFetcher,
		genesisTimeFetcher:    cfg.GenesisTimeFetcher,
		attestationReceiver:   cfg.AttestationReceiver,
		blockReceiver:         cfg.BlockReceiver,
		p2p:                   cfg.Broadcaster,
		peersFetcher:          cfg.PeersFetcher,
		powChainService:       cfg.POWChainService,
		chainStartFetcher:     cfg.ChainStartFetcher,
		mockEth1Votes:         cfg.MockEth1Votes,
		attestationsPool:      cfg.AttestationsPool,
		exitPool:              cfg.ExitPool,
		syncService:           cfg.SyncService,
		host:                  cfg.Host,
		port:                  cfg.Port,
		withCert:              cfg.CertFlag,
		withKey:               cfg.KeyFlag,
		depositFetcher:        cfg.DepositFetcher,
		pendingDepositFetcher: cfg.PendingDepositFetcher,
		canonicalStateChan:    make(chan *pbp2p.BeaconState, params.BeaconConfig().DefaultBufferSize),
		incomingAttestation:   make(chan *ethpb.Attestation, params.BeaconConfig().DefaultBufferSize),
		stateNotifier:         cfg.StateNotifier,
		operationNotifier:     cfg.OperationNotifier,
		slasherProvider:       cfg.SlasherProvider,
		slasherCert:           cfg.SlasherCert,
	}
}

// Start the gRPC server.
func (s *Service) Start() {
	address := fmt.Sprintf("%s:%s", s.host, s.port)
	lis, err := net.Listen("tcp", address)
	if err != nil {
		log.Errorf("Could not listen to port in Start() %s: %v", address, err)
	}
	s.listener = lis
	log.WithField("address", address).Info("RPC-API listening on port")

	opts := []grpc.ServerOption{
		grpc.StatsHandler(&ocgrpc.ServerHandler{}),
		grpc.StreamInterceptor(middleware.ChainStreamServer(
			recovery.StreamServerInterceptor(
				recovery.WithRecoveryHandlerContext(traceutil.RecoveryHandlerFunc),
			),
			grpc_prometheus.StreamServerInterceptor,
			grpc_opentracing.StreamServerInterceptor(),
		)),
		grpc.UnaryInterceptor(middleware.ChainUnaryServer(
			recovery.UnaryServerInterceptor(
				recovery.WithRecoveryHandlerContext(traceutil.RecoveryHandlerFunc),
			),
			grpc_prometheus.UnaryServerInterceptor,
			grpc_opentracing.UnaryServerInterceptor(),
		)),
	}
	grpc_prometheus.EnableHandlingTimeHistogram()
	// TODO(#791): Utilize a certificate for secure connections
	// between beacon nodes and validator clients.
	if s.withCert != "" && s.withKey != "" {
		creds, err := credentials.NewServerTLSFromFile(s.withCert, s.withKey)
		if err != nil {
			log.Errorf("Could not load TLS keys: %s", err)
			s.credentialError = err
		}
		opts = append(opts, grpc.Creds(creds))
	} else {
		log.Warn("You are using an insecure gRPC connection! Provide a certificate and key to connect securely")
	}
	s.grpcServer = grpc.NewServer(opts...)

	genesisTime := s.genesisTimeFetcher.GenesisTime()
	ticker := slotutil.GetSlotTicker(genesisTime, params.BeaconConfig().SecondsPerSlot)
	validatorServer := &validator.Server{
		Ctx:                    s.ctx,
		BeaconDB:               s.beaconDB,
		AttestationCache:       cache.NewAttestationCache(),
		AttPool:                s.attestationsPool,
		ExitPool:               s.exitPool,
		HeadFetcher:            s.headFetcher,
		ForkFetcher:            s.forkFetcher,
		FinalizationFetcher:    s.finalizationFetcher,
		CanonicalStateChan:     s.canonicalStateChan,
		BlockFetcher:           s.powChainService,
		DepositFetcher:         s.depositFetcher,
		ChainStartFetcher:      s.chainStartFetcher,
		Eth1InfoFetcher:        s.powChainService,
		SyncChecker:            s.syncService,
		StateNotifier:          s.stateNotifier,
		OperationNotifier:      s.operationNotifier,
		P2P:                    s.p2p,
		BlockReceiver:          s.blockReceiver,
		MockEth1Votes:          s.mockEth1Votes,
		Eth1BlockFetcher:       s.powChainService,
		PendingDepositsFetcher: s.pendingDepositFetcher,
		GenesisTime:            genesisTime,
	}
	nodeServer := &node.Server{
		BeaconDB:           s.beaconDB,
		Server:             s.grpcServer,
		SyncChecker:        s.syncService,
		GenesisTimeFetcher: s.genesisTimeFetcher,
		PeersFetcher:       s.peersFetcher,
	}
	beaconChainServer := &beacon.Server{
		Ctx:                  s.ctx,
		BeaconDB:             s.beaconDB,
		Pool:                 s.attestationsPool,
		HeadFetcher:          s.headFetcher,
		FinalizationFetcher:  s.finalizationFetcher,
		ParticipationFetcher: s.participationFetcher,
		ChainStartFetcher:    s.chainStartFetcher,
		CanonicalStateChan:   s.canonicalStateChan,
		StateNotifier:        s.stateNotifier,
		SlotTicker:           ticker,
	}
	aggregatorServer := &aggregator.Server{
		BeaconDB:    s.beaconDB,
		HeadFetcher: s.headFetcher,
		SyncChecker: s.syncService,
		AttPool:     s.attestationsPool,
		P2p:         s.p2p,
	}
	pb.RegisterAggregatorServiceServer(s.grpcServer, aggregatorServer)
	ethpb.RegisterNodeServer(s.grpcServer, nodeServer)
	ethpb.RegisterBeaconChainServer(s.grpcServer, beaconChainServer)
	ethpb.RegisterBeaconNodeValidatorServer(s.grpcServer, validatorServer)

	// Register reflection service on gRPC server.
	reflection.Register(s.grpcServer)

	go func() {
		if s.listener != nil {
			if err := s.grpcServer.Serve(s.listener); err != nil {
				log.Errorf("Could not serve gRPC: %v", err)
			}
		}
	}()
	if featureconfig.Get().EnableSlasherConnection {
		s.startSlasherClient()
	}
}

func (s *Service) startSlasherClient() {
	var dialOpt grpc.DialOption
	if s.slasherCert != "" {
		creds, err := credentials.NewClientTLSFromFile(s.slasherCert, "")
		if err != nil {
			log.Errorf("Could not get valid credentials: %v", err)
			s.slasherCredentialError = err
		}
		dialOpt = grpc.WithTransportCredentials(creds)
	} else {
		dialOpt = grpc.WithInsecure()
		log.Warn("You are using an insecure gRPC connection! Please provide a certificate and key to use a secure connection.")
	}
	slasherOpts := []grpc.DialOption{
		dialOpt,
		grpc.WithStatsHandler(&ocgrpc.ClientHandler{}),
		grpc.WithStreamInterceptor(middleware.ChainStreamClient(
			grpc_opentracing.StreamClientInterceptor(),
			grpc_prometheus.StreamClientInterceptor,
		)),
		grpc.WithUnaryInterceptor(middleware.ChainUnaryClient(
			grpc_opentracing.UnaryClientInterceptor(),
			grpc_prometheus.UnaryClientInterceptor,
		)),
	}
	conn, err := grpc.DialContext(s.ctx, s.slasherProvider, slasherOpts...)
	if err != nil {
		log.Errorf("Could not dial endpoint: %s, %v", s.slasherProvider, err)
		return
	}
	log.Info("Successfully started hash slinging slasher©️ gRPC connection")
	s.slasherConn = conn
	s.slasherClient = slashpb.NewSlasherClient(s.slasherConn)
}

// Stop the service.
func (s *Service) Stop() error {
	s.cancel()
	if s.listener != nil {
		s.grpcServer.GracefulStop()
		log.Debug("Initiated graceful stop of gRPC server")
	}
	if s.slasherConn != nil {
		s.slasherConn.Close()
	}
	return nil
}

// Status returns nil or credentialError
func (s *Service) Status() error {
	if s.credentialError != nil {
		return s.credentialError
	}
	if s.slasherCredentialError != nil {
		return s.slasherCredentialError
	}
	return nil
}