Try #4846:

cmd/base.go

@@ -168,6 +168,14 @@ func EnsureCLIFlags(cmd *cobra.Command, appCFG *config.Config) error {
 			elem = reflect.ValueOf(&appCFG.Recovery).Elem()
 			assignFields(ff, elem, name)
 
+			ff = reflect.TypeOf(appCFG.Sync)
+			elem = reflect.ValueOf(&appCFG.Sync).Elem()
+			assignFields(ff, elem, name)
+
+			ff = reflect.TypeOf(appCFG.FETCH)
+			elem = reflect.ValueOf(&appCFG.FETCH).Elem()
+			assignFields(ff, elem, name)
+
 			ff = reflect.TypeOf(appCFG.TestConfig)
 			elem = reflect.ValueOf(&appCFG.TestConfig).Elem()
 			assignFields(ff, elem, name)

cmd/root.go

@@ -268,6 +268,14 @@ func AddCommands(cmd *cobra.Command) {
 	cmd.PersistentFlags().StringVar(&cfg.TestConfig.SmesherKey, "testing-smesher-key",
 		"", "import private smesher key for testing",
 	)
+	// TODO remove after sync protocol update
+	cmd.PersistentFlags().BoolVar(&cfg.Sync.UseNewProtocol, "use-new-opn",
+		cfg.Sync.UseNewProtocol, "use new opinions sync protocol",
+	)
+	// TODO remove after sync protocol update
+	cmd.PersistentFlags().BoolVar(&cfg.FETCH.ServeNewProtocol, "serve-new-opn",
+		cfg.FETCH.ServeNewProtocol, "serve new opinions sync protocol",
+	)
 
 	// Bind Flags to config
 	err := viper.BindPFlags(cmd.PersistentFlags())

config/mainnet.go

@@ -134,6 +134,7 @@ func MainnetConfig() Config {
 			Interval:         time.Minute,
 			EpochEndFraction: 0.8,
 			MaxStaleDuration: time.Hour,
+			UseNewProtocol:   true,
 			Standalone:       false,
 		},
 		Recovery: checkpoint.DefaultConfig(),

fetch/fetch.go

@@ -9,6 +9,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/libp2p/go-libp2p/core/protocol"
 	"golang.org/x/sync/errgroup"
 
 	"github.com/spacemeshos/go-spacemesh/codec"
@@ -28,6 +29,8 @@ const (
 	meshHashProtocol = "mh/1"
 	malProtocol      = "ml/1"
 
+	OpnProtocol = "lp/2"
+
 	cacheSize = 1000
 )
 
@@ -82,6 +85,7 @@ type Config struct {
 	BatchSize, QueueSize int
 	RequestTimeout       time.Duration // in seconds
 	MaxRetriesForRequest int
+	ServeNewProtocol     bool `mapstructure:"serve-new-opn"`
 }
 
 // DefaultConfig is the default config for the fetch component.
@@ -93,6 +97,7 @@ func DefaultConfig() Config {
 		BatchSize:            20,
 		RequestTimeout:       time.Second * time.Duration(10),
 		MaxRetriesForRequest: 100,
+		ServeNewProtocol:     true,
 	}
 }
 
@@ -187,13 +192,16 @@ func NewFetch(cdb *datastore.CachedDB, msh meshProvider, b system.BeaconGetter,
 		server.WithLog(f.logger),
 	}
 	if len(f.servers) == 0 {
-		h := newHandler(cdb, bs, msh, b, f.logger)
+		h := newHandler(cdb, bs, msh, b, f.cfg.ServeNewProtocol, f.logger)
 		f.servers[atxProtocol] = server.New(host, atxProtocol, h.handleEpochInfoReq, srvOpts...)
 		f.servers[lyrDataProtocol] = server.New(host, lyrDataProtocol, h.handleLayerDataReq, srvOpts...)
 		f.servers[lyrOpnsProtocol] = server.New(host, lyrOpnsProtocol, h.handleLayerOpinionsReq, srvOpts...)
 		f.servers[hashProtocol] = server.New(host, hashProtocol, h.handleHashReq, srvOpts...)
 		f.servers[meshHashProtocol] = server.New(host, meshHashProtocol, h.handleMeshHashReq, srvOpts...)
 		f.servers[malProtocol] = server.New(host, malProtocol, h.handleMaliciousIDsReq, srvOpts...)
+		if f.cfg.ServeNewProtocol {
+			f.servers[OpnProtocol] = server.New(host, OpnProtocol, h.handleLayerOpinionsReq2, srvOpts...)
+		}
 	}
 	return f
 }
@@ -644,3 +652,7 @@ func (f *Fetch) RegisterPeerHashes(peer p2p.Peer, hashes []types.Hash32) {
 func (f *Fetch) GetPeers() []p2p.Peer {
 	return f.host.GetPeers()
 }
+
+func (f *Fetch) PeerProtocols(p p2p.Peer) ([]protocol.ID, error) {
+	return f.host.PeerProtocols(p)
+}

fetch/fetch_test.go

@@ -31,6 +31,7 @@ type testFetch struct {
 	mOpnS   *mocks.Mockrequester
 	mHashS  *mocks.Mockrequester
 	mMHashS *mocks.Mockrequester
+	mOpn2S  *mocks.Mockrequester
 
 	mMesh        *mocks.MockmeshProvider
 	mMalH        *mocks.MockSyncValidator
@@ -54,6 +55,7 @@ func createFetch(tb testing.TB) *testFetch {
 		mOpnS:        mocks.NewMockrequester(ctrl),
 		mHashS:       mocks.NewMockrequester(ctrl),
 		mMHashS:      mocks.NewMockrequester(ctrl),
+		mOpn2S:       mocks.NewMockrequester(ctrl),
 		mMalH:        mocks.NewMockSyncValidator(ctrl),
 		mAtxH:        mocks.NewMockSyncValidator(ctrl),
 		mBallotH:     mocks.NewMockSyncValidator(ctrl),
@@ -64,12 +66,13 @@ func createFetch(tb testing.TB) *testFetch {
 		mPoetH:       mocks.NewMockSyncValidator(ctrl),
 	}
 	cfg := Config{
-		time.Millisecond * time.Duration(2000), // make sure we never hit the batch timeout
-		3,
-		3,
-		1000,
-		time.Second * time.Duration(3),
-		3,
+		BatchTimeout:         time.Millisecond * time.Duration(2000), // make sure we never hit the batch timeout
+		MaxRetriesForPeer:    3,
+		BatchSize:            3,
+		QueueSize:            1000,
+		RequestTimeout:       time.Second * time.Duration(3),
+		MaxRetriesForRequest: 3,
+		ServeNewProtocol:     true,
 	}
 	lg := logtest.New(tb)
 	tf.Fetch = NewFetch(datastore.NewCachedDB(sql.InMemory(), lg), tf.mMesh, nil, nil,
@@ -83,6 +86,7 @@ func createFetch(tb testing.TB) *testFetch {
 			lyrOpnsProtocol:  tf.mOpnS,
 			hashProtocol:     tf.mHashS,
 			meshHashProtocol: tf.mMHashS,
+			OpnProtocol:      tf.mOpn2S,
 		}),
 		withHost(tf.mh))
 	tf.Fetch.SetValidators(tf.mAtxH, tf.mPoetH, tf.mBallotH, tf.mBlocksH, tf.mProposalH, tf.mTxBlocksH, tf.mTxProposalH, tf.mMalH)
@@ -315,12 +319,13 @@ func TestFetch_PeerDroppedWhenMessageResultsInValidationReject(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), time.Second*30)
 	defer cancel()
 	cfg := Config{
-		time.Minute * time.Duration(2000), // make sure we never hit the batch timeout
-		3,
-		3,
-		1000,
-		time.Second * time.Duration(3),
-		3,
+		BatchTimeout:         time.Minute * time.Duration(2000), // make sure we never hit the batch timeout
+		MaxRetriesForPeer:    3,
+		BatchSize:            3,
+		QueueSize:            1000,
+		RequestTimeout:       time.Second * time.Duration(3),
+		MaxRetriesForRequest: 3,
+		ServeNewProtocol:     true,
 	}
 	p2pconf := p2p.DefaultConfig()
 	p2pconf.Listen = "/ip4/127.0.0.1/tcp/0"