// startFakeServerGossip creates local gossip instances and remote faked gossip instance.
// The remote gossip instance launches its faked gossip service just for
// check the client message.
func startFakeServerGossip(t *testing.T) (local *Gossip, remote *fakeGossipServer, stopper *stop.Stopper) {
	lclock := hlc.NewClock(hlc.UnixNano)
	stopper = stop.NewStopper()
	lRPCContext := rpc.NewContext(&base.Context{Insecure: true}, lclock, stopper)

	laddr := util.CreateTestAddr("tcp")
	lserver := rpc.NewServer(laddr, lRPCContext)
	if err := lserver.Start(); err != nil {
		t.Fatal(err)
	}
	local = New(lRPCContext, TestBootstrap)
	local.start(lserver, stopper)

	rclock := hlc.NewClock(hlc.UnixNano)
	raddr := util.CreateTestAddr("tcp")
	rRPCContext := rpc.NewContext(&base.Context{Insecure: true}, rclock, stopper)
	rserver := rpc.NewServer(raddr, rRPCContext)
	if err := rserver.Start(); err != nil {
		t.Fatal(err)
	}

	remote, err := newFakeGossipServer(rserver, stopper)
	if err != nil {
		t.Fatal(err)
	}
	addr := rserver.Addr()
	remote.nodeAddr = util.MakeUnresolvedAddr(addr.Network(), addr.String())
	time.Sleep(time.Millisecond)
	return
}

// createTestNode creates an rpc server using the specified address,
// gossip instance, KV database and a node using the specified slice
// of engines. The server, clock and node are returned. If gossipBS is
// not nil, the gossip bootstrap address is set to gossipBS.
func createTestNode(addr net.Addr, engines []engine.Engine, gossipBS net.Addr, t *testing.T) (
	*rpc.Server, *hlc.Clock, *Node, *util.Stopper) {
	var err error
	ctx := storage.StoreContext{}

	stopper := util.NewStopper()
	ctx.Clock = hlc.NewClock(hlc.UnixNano)
	serverContext := rpc.NewContext(serverTestBaseContext, ctx.Clock, stopper)
	ctx.ScanInterval = 10 * time.Hour
	rpcServer := rpc.NewServer(addr, serverContext)
	if err := rpcServer.Start(); err != nil {
		t.Fatal(err)
	}
	rpcContext := rpc.NewContext(serverTestBaseContext, ctx.Clock, stopper)
	g := gossip.New(rpcContext, testContext.GossipInterval, testContext.GossipBootstrapResolvers)
	if gossipBS != nil {
		// Handle possibility of a :0 port specification.
		if gossipBS == addr {
			gossipBS = rpcServer.Addr()
		}
		g.SetResolvers([]resolver.Resolver{resolver.NewResolverFromAddress(gossipBS)})
		g.Start(rpcServer, stopper)
	}
	ctx.Gossip = g
	sender := kv.NewDistSender(&kv.DistSenderContext{Clock: ctx.Clock}, g)
	if ctx.DB, err = client.Open("//[email protected]", client.SenderOpt(sender)); err != nil {
		t.Fatal(err)
	}
	// TODO(bdarnell): arrange to have the transport closed.
	ctx.Transport = multiraft.NewLocalRPCTransport()
	ctx.EventFeed = &util.Feed{}
	node := NewNode(ctx)
	return rpcServer, ctx.Clock, node, stopper
}

// startFakeServerGossips creates local gossip instances and remote
// faked gossip instance. The remote gossip instance launches its
// faked gossip service just for check the client message.
func startFakeServerGossips(t *testing.T) (local *Gossip, remote *fakeGossipServer, stopper *stop.Stopper) {
	stopper = stop.NewStopper()
	lRPCContext := rpc.NewContext(&base.Context{Insecure: true}, nil, stopper)

	lserver := rpc.NewServer(lRPCContext)
	lln, err := util.ListenAndServeGRPC(stopper, lserver, util.TestAddr)
	if err != nil {
		t.Fatal(err)
	}
	local = New(lRPCContext, nil, stopper)
	local.start(lserver, lln.Addr())

	rRPCContext := rpc.NewContext(&base.Context{Insecure: true}, nil, stopper)

	rserver := rpc.NewServer(rRPCContext)
	rln, err := util.ListenAndServeGRPC(stopper, rserver, util.TestAddr)
	if err != nil {
		t.Fatal(err)
	}

	remote = newFakeGossipServer(rserver, stopper)
	addr := rln.Addr()
	remote.nodeAddr = util.MakeUnresolvedAddr(addr.Network(), addr.String())
	return
}

// startGossip creates local and remote gossip instances.
// Both remote and local instances launch the gossip service.
func startGossip(t *testing.T) (local, remote *Gossip, stopper *stop.Stopper) {
	stopper = stop.NewStopper()
	lclock := hlc.NewClock(hlc.UnixNano)
	lRPCContext := rpc.NewContext(&base.Context{Insecure: true}, lclock, stopper)

	laddr := util.CreateTestAddr("tcp")
	lserver := rpc.NewServer(lRPCContext)
	lTLSConfig, err := lRPCContext.GetServerTLSConfig()
	if err != nil {
		t.Fatal(err)
	}
	lln, err := util.ListenAndServe(stopper, lserver, laddr, lTLSConfig)
	if err != nil {
		t.Fatal(err)
	}
	local = New(lRPCContext, TestBootstrap)
	local.SetNodeID(1)
	if err := local.SetNodeDescriptor(&roachpb.NodeDescriptor{
		NodeID:  1,
		Address: util.MakeUnresolvedAddr(laddr.Network(), laddr.String()),
	}); err != nil {
		t.Fatal(err)
	}

	rclock := hlc.NewClock(hlc.UnixNano)
	rRPCContext := rpc.NewContext(&base.Context{Insecure: true}, rclock, stopper)

	raddr := util.CreateTestAddr("tcp")
	rserver := rpc.NewServer(rRPCContext)
	rTLSConfig, err := rRPCContext.GetServerTLSConfig()
	if err != nil {
		t.Fatal(err)
	}
	rln, err := util.ListenAndServe(stopper, rserver, raddr, rTLSConfig)
	if err != nil {
		t.Fatal(err)
	}
	remote = New(rRPCContext, TestBootstrap)
	remote.SetNodeID(2)
	if err := remote.SetNodeDescriptor(&roachpb.NodeDescriptor{
		NodeID:  2,
		Address: util.MakeUnresolvedAddr(raddr.Network(), raddr.String()),
	}); err != nil {
		t.Fatal(err)
	}
	local.start(lserver, lln.Addr(), stopper)
	remote.start(rserver, rln.Addr(), stopper)
	time.Sleep(time.Millisecond)
	return
}

// createTestStoreWithEngine creates a test store using the given engine and clock.
// The caller is responsible for closing the store on exit.
func createTestStoreWithEngine(t *testing.T, eng engine.Engine, clock *hlc.Clock,
	bootstrap bool) *storage.Store {
	rpcContext := rpc.NewContext(hlc.NewClock(hlc.UnixNano), rpc.LoadInsecureTLSConfig())
	g := gossip.New(rpcContext, gossip.TestInterval, "")
	lSender := kv.NewLocalSender()
	sender := kv.NewTxnCoordSender(lSender, clock, false)
	db := client.NewKV(sender, nil)
	db.User = storage.UserRoot
	// TODO(bdarnell): arrange to have the transport closed.
	store := storage.NewStore(clock, eng, db, g, multiraft.NewLocalRPCTransport())
	if bootstrap {
		if err := store.Bootstrap(proto.StoreIdent{NodeID: 1, StoreID: 1}); err != nil {
			t.Fatal(err)
		}
	}
	lSender.AddStore(store)
	if bootstrap {
		if err := store.BootstrapRange(); err != nil {
			t.Fatal(err)
		}
	}
	if err := store.Start(); err != nil {
		t.Fatal(err)
	}
	return store
}

// TestClientNodeID verifies a client's gossip request with correct NodeID.
func TestClientNodeID(t *testing.T) {
	defer leaktest.AfterTest(t)()

	local, remote, stopper := startFakeServerGossips(t)
	nodeID := roachpb.NodeID(1)
	local.SetNodeID(nodeID)

	disconnected := make(chan *client, 1)

	// Use an insecure context. We're talking to tcp socket which are not in the certs.
	lclock := hlc.NewClock(hlc.UnixNano)
	rpcContext := rpc.NewContext(&base.Context{Insecure: true}, lclock, stopper)

	// Start a gossip client.
	c := newClient(&remote.nodeAddr)
	defer func() {
		stopper.Stop()
		if c != <-disconnected {
			t.Errorf("expected client disconnect after remote close")
		}
	}()

	c.start(local, disconnected, rpcContext, stopper)
	// Wait for c.gossip to start.
	if receivedNodeID := <-remote.nodeIDChan; receivedNodeID != nodeID {
		t.Errorf("client should send NodeID with %v, got %v", nodeID, receivedNodeID)
	}
}

// NewNetwork creates nodeCount gossip nodes.
func NewNetwork(nodeCount int) *Network {
	clock := hlc.NewClock(hlc.UnixNano)

	log.Infof("simulating gossip network with %d nodes", nodeCount)

	n := &Network{
		Nodes:   []*Node{},
		Stopper: stop.NewStopper(),
	}
	n.rpcContext = rpc.NewContext(&base.Context{Insecure: true}, clock, n.Stopper)
	var err error
	n.tlsConfig, err = n.rpcContext.GetServerTLSConfig()
	if err != nil {
		log.Fatal(err)
	}

	for i := 0; i < nodeCount; i++ {
		node, err := n.CreateNode()
		if err != nil {
			log.Fatal(err)
		}
		// Build a resolver for each instance or we'll get data races.
		r, err := resolver.NewResolverFromAddress(n.Nodes[0].Addr)
		if err != nil {
			log.Fatalf("bad gossip address %s: %s", n.Nodes[0].Addr, err)
		}
		node.Gossip.SetResolvers([]resolver.Resolver{r})
		if err := n.StartNode(node); err != nil {
			log.Fatal(err)
		}
	}
	return n
}

// createTestStoreWithEngine creates a test store using the given engine and clock.
// The caller is responsible for closing the store on exit.
func createTestStoreWithEngine(t *testing.T, eng engine.Engine, clock *hlc.Clock,
	bootstrap bool, context *storage.StoreContext) (*storage.Store, *stop.Stopper) {
	stopper := stop.NewStopper()
	rpcContext := rpc.NewContext(&base.Context{}, hlc.NewClock(hlc.UnixNano), stopper)
	if context == nil {
		// make a copy
		ctx := storage.TestStoreContext
		context = &ctx
	}
	context.Gossip = gossip.New(rpcContext, gossip.TestInterval, gossip.TestBootstrap)
	lSender := kv.NewLocalSender()
	sender := kv.NewTxnCoordSender(lSender, clock, false, nil, stopper)
	context.Clock = clock
	context.DB = client.NewDB(sender)
	context.Transport = multiraft.NewLocalRPCTransport(stopper)
	// TODO(bdarnell): arrange to have the transport closed.
	store := storage.NewStore(*context, eng, &proto.NodeDescriptor{NodeID: 1})
	if bootstrap {
		if err := store.Bootstrap(proto.StoreIdent{NodeID: 1, StoreID: 1}, stopper); err != nil {
			t.Fatal(err)
		}
	}
	lSender.AddStore(store)
	if bootstrap {
		if err := store.BootstrapRange(nil); err != nil {
			t.Fatal(err)
		}
	}
	if err := store.Start(stopper); err != nil {
		t.Fatal(err)
	}
	return store, stopper
}

// createTestStoreWithoutStart creates a test store using an in-memory
// engine without starting the store. It returns the store, the store
// clock's manual unix nanos time and a stopper. The caller is
// responsible for stopping the stopper upon completion.
func createTestStoreWithoutStart(t *testing.T) (*Store, *hlc.ManualClock, *stop.Stopper) {
	stopper := stop.NewStopper()
	// Setup fake zone config handler.
	config.TestingSetupZoneConfigHook(stopper)
	rpcContext := rpc.NewContext(&base.Context{}, hlc.NewClock(hlc.UnixNano), stopper)
	ctx := TestStoreContext
	ctx.Gossip = gossip.New(rpcContext, gossip.TestInterval, gossip.TestBootstrap)
	ctx.StorePool = NewStorePool(ctx.Gossip, TestTimeUntilStoreDeadOff, stopper)
	manual := hlc.NewManualClock(0)
	ctx.Clock = hlc.NewClock(manual.UnixNano)
	eng := engine.NewInMem(roachpb.Attributes{}, 10<<20, stopper)
	ctx.Transport = multiraft.NewLocalRPCTransport(stopper)
	stopper.AddCloser(ctx.Transport)
	sender := &testSender{}
	ctx.DB = client.NewDB(sender)
	store := NewStore(ctx, eng, &roachpb.NodeDescriptor{NodeID: 1})
	sender.store = store
	if err := store.Bootstrap(roachpb.StoreIdent{NodeID: 1, StoreID: 1}, stopper); err != nil {
		t.Fatal(err)
	}
	if err := store.BootstrapRange(nil); err != nil {
		t.Fatal(err)
	}
	return store, manual, stopper
}

// createTestStoreWithEngine creates a test store using the given engine and clock.
// The caller is responsible for closing the store on exit.
func createTestStoreWithEngine(t *testing.T, eng engine.Engine, clock *hlc.Clock,
	bootstrap bool, sCtx *storage.StoreContext) (*storage.Store, *stop.Stopper) {
	stopper := stop.NewStopper()
	rpcContext := rpc.NewContext(&base.Context{}, clock, stopper)
	if sCtx == nil {
		// make a copy
		ctx := storage.TestStoreContext
		sCtx = &ctx
	}
	nodeDesc := &proto.NodeDescriptor{NodeID: 1}
	sCtx.Gossip = gossip.New(rpcContext, gossip.TestInterval, gossip.TestBootstrap)
	localSender := kv.NewLocalSender()
	rpcSend := func(_ rpc.Options, _ string, _ []net.Addr,
		getArgs func(addr net.Addr) gogoproto.Message, getReply func() gogoproto.Message,
		_ *rpc.Context) ([]gogoproto.Message, error) {
		call := proto.Call{
			Args:  getArgs(nil /* net.Addr */).(proto.Request),
			Reply: getReply().(proto.Response),
		}
		localSender.Send(context.Background(), call)
		return []gogoproto.Message{call.Reply}, call.Reply.Header().GoError()
	}

	// Mostly makes sure that we don't see a warning per request.
	{
		if err := sCtx.Gossip.AddInfoProto(gossip.MakeNodeIDKey(nodeDesc.NodeID), nodeDesc, time.Hour); err != nil {
			t.Fatal(err)
		}
		if err := sCtx.Gossip.SetNodeDescriptor(nodeDesc); err != nil {
			t.Fatal(err)
		}
	}
	distSender := kv.NewDistSender(&kv.DistSenderContext{
		Clock:             clock,
		RPCSend:           rpcSend,     // defined above
		RangeDescriptorDB: localSender, // for descriptor lookup
	}, sCtx.Gossip)

	sender := kv.NewTxnCoordSender(distSender, clock, false, nil, stopper)
	sCtx.Clock = clock
	sCtx.DB = client.NewDB(sender)
	sCtx.Transport = multiraft.NewLocalRPCTransport(stopper)
	// TODO(bdarnell): arrange to have the transport closed.
	store := storage.NewStore(*sCtx, eng, nodeDesc)
	if bootstrap {
		if err := store.Bootstrap(proto.StoreIdent{NodeID: 1, StoreID: 1}, stopper); err != nil {
			t.Fatal(err)
		}
	}
	localSender.AddStore(store)
	if bootstrap {
		if err := store.BootstrapRange(sql.GetInitialSystemValues()); err != nil {
			t.Fatal(err)
		}
	}
	if err := store.Start(stopper); err != nil {
		t.Fatal(err)
	}
	return store, stopper
}

// NewNetwork creates nodeCount gossip nodes.
func NewNetwork(nodeCount int, createResolvers bool) *Network {
	log.Infof(context.TODO(), "simulating gossip network with %d nodes", nodeCount)

	n := &Network{
		Nodes:   []*Node{},
		Stopper: stop.NewStopper(),
	}
	n.rpcContext = rpc.NewContext(&base.Context{Insecure: true}, nil, n.Stopper)
	var err error
	n.tlsConfig, err = n.rpcContext.GetServerTLSConfig()
	if err != nil {
		log.Fatal(context.TODO(), err)
	}

	for i := 0; i < nodeCount; i++ {
		node, err := n.CreateNode()
		if err != nil {
			log.Fatal(context.TODO(), err)
		}
		// Build a resolver for each instance or we'll get data races.
		if createResolvers {
			r, err := resolver.NewResolverFromAddress(n.Nodes[0].Addr())
			if err != nil {
				log.Fatalf(context.TODO(), "bad gossip address %s: %s", n.Nodes[0].Addr(), err)
			}
			node.Gossip.SetResolvers([]resolver.Resolver{r})
		}
	}
	return n
}

// TestGossipInfoStore verifies operation of gossip instance infostore.
func TestGossipInfoStore(t *testing.T) {
	defer leaktest.AfterTest(t)
	rpcContext := rpc.NewContext(rootTestBaseContext, hlc.NewClock(hlc.UnixNano), nil)
	g := New(rpcContext, TestInterval, TestBootstrap)
	if err := g.AddInfo("i", int64(1), time.Hour); err != nil {
		t.Fatal(err)
	}
	if val, err := g.GetInfo("i"); val.(int64) != int64(1) || err != nil {
		t.Errorf("error fetching int64: %v", err)
	}
	if _, err := g.GetInfo("i2"); err == nil {
		t.Errorf("expected error fetching nonexistent key \"i2\"")
	}
	if err := g.AddInfo("f", float64(3.14), time.Hour); err != nil {
		t.Fatal(err)
	}
	if val, err := g.GetInfo("f"); val.(float64) != float64(3.14) || err != nil {
		t.Errorf("error fetching float64: %v", err)
	}
	if _, err := g.GetInfo("f2"); err == nil {
		t.Errorf("expected error fetching nonexistent key \"f2\"")
	}
	if err := g.AddInfo("s", "b", time.Hour); err != nil {
		t.Fatal(err)
	}
	if val, err := g.GetInfo("s"); val.(string) != "b" || err != nil {
		t.Errorf("error fetching string: %v", err)
	}
	if _, err := g.GetInfo("s2"); err == nil {
		t.Errorf("expected error fetching nonexistent key \"s2\"")
	}
}

// createTestStorePool creates a stopper, gossip and storePool for use in
// tests. Stopper must be stopped by the caller.
func createTestStorePool(timeUntilStoreDead time.Duration) (*stop.Stopper, *gossip.Gossip, *StorePool) {
	stopper := stop.NewStopper()
	rpcContext := rpc.NewContext(&base.Context{}, hlc.NewClock(hlc.UnixNano), stopper)
	g := gossip.New(rpcContext, gossip.TestInterval, gossip.TestBootstrap)
	storePool := NewStorePool(g, timeUntilStoreDead, stopper)
	return stopper, g, storePool
}

// TestClientGossip verifies a client can gossip a delta to the server.
func TestClientGossip(t *testing.T) {
	defer leaktest.AfterTest(t)
	local, remote, stopper := startGossip(t)
	if err := local.AddInfo("local-key", "local value", time.Second); err != nil {
		t.Fatal(err)
	}
	if err := remote.AddInfo("remote-key", "remote value", time.Second); err != nil {
		t.Fatal(err)
	}
	disconnected := make(chan *client, 1)

	client := newClient(remote.is.NodeAddr)
	// Use an insecure context. We're talking to unix socket which are not in the certs.
	lclock := hlc.NewClock(hlc.UnixNano)
	rpcContext := rpc.NewContext(insecureTestBaseContext, lclock, stopper)
	client.start(local, disconnected, rpcContext, stopper)

	if err := util.IsTrueWithin(func() bool {
		_, lerr := remote.GetInfo("local-key")
		_, rerr := local.GetInfo("remote-key")
		return lerr == nil && rerr == nil
	}, 500*time.Millisecond); err != nil {
		t.Errorf("gossip exchange failed or taking too long")
	}

	stopper.Stop()
	log.Info("done serving")
	if client != <-disconnected {
		t.Errorf("expected client disconnect after remote close")
	}
}

// createTestNode creates an rpc server using the specified address,
// gossip instance, KV database and a node using the specified slice
// of engines. The server, clock and node are returned. If gossipBS is
// not nil, the gossip bootstrap address is set to gossipBS.
func createTestNode(addr net.Addr, engines []engine.Engine, gossipBS net.Addr, t *testing.T) (
	*rpc.Server, *hlc.Clock, *Node, *stop.Stopper) {
	ctx := storage.StoreContext{}

	stopper := stop.NewStopper()
	ctx.Clock = hlc.NewClock(hlc.UnixNano)
	nodeRPCContext := rpc.NewContext(nodeTestBaseContext, ctx.Clock, stopper)
	ctx.ScanInterval = 10 * time.Hour
	rpcServer := rpc.NewServer(addr, nodeRPCContext)
	if err := rpcServer.Start(); err != nil {
		t.Fatal(err)
	}
	g := gossip.New(nodeRPCContext, testContext.GossipInterval, testContext.GossipBootstrapResolvers)
	if gossipBS != nil {
		// Handle possibility of a :0 port specification.
		if gossipBS == addr {
			gossipBS = rpcServer.Addr()
		}
		g.SetResolvers([]resolver.Resolver{resolver.NewResolverFromAddress(gossipBS)})
		g.Start(rpcServer, stopper)
	}
	ctx.Gossip = g
	sender := (*callDistSender)(kv.NewDistSender(&kv.DistSenderContext{Clock: ctx.Clock}, g))
	ctx.DB = client.NewDB(sender)
	// TODO(bdarnell): arrange to have the transport closed.
	// (or attach LocalRPCTransport.Close to the stopper)
	ctx.Transport = multiraft.NewLocalRPCTransport(stopper)
	ctx.EventFeed = util.NewFeed(stopper)
	node := NewNode(ctx)
	return rpcServer, ctx.Clock, node, stopper
}

func (m *multiTestContext) Start(t *testing.T, numStores int) {
	if m.manualClock == nil {
		m.manualClock = hlc.NewManualClock(0)
	}
	if m.clock == nil {
		m.clock = hlc.NewClock(m.manualClock.UnixNano)
	}
	if m.gossip == nil {
		rpcContext := rpc.NewContext(m.clock, rpc.LoadInsecureTLSConfig())
		m.gossip = gossip.New(rpcContext, gossip.TestInterval, "")
	}
	if m.transport == nil {
		m.transport = multiraft.NewLocalRPCTransport()
	}
	if m.sender == nil {
		m.sender = kv.NewLocalSender()
	}
	if m.db == nil {
		txnSender := kv.NewTxnCoordSender(m.sender, m.clock, false)
		m.db = client.NewKV(txnSender, nil)
		m.db.User = storage.UserRoot
	}

	for i := 0; i < numStores; i++ {
		m.addStore(t)
	}
}

func TestSpanStatsGRPCResponse(t *testing.T) {
	defer leaktest.AfterTest(t)()
	ts := startServer(t)
	defer ts.Stopper().Stop()

	rpcStopper := stop.NewStopper()
	defer rpcStopper.Stop()
	rpcContext := rpc.NewContext(ts.RPCContext().Context, ts.Clock(), rpcStopper)
	request := serverpb.SpanStatsRequest{
		NodeID:   "1",
		StartKey: []byte(roachpb.RKeyMin),
		EndKey:   []byte(roachpb.RKeyMax),
	}

	url := ts.ServingAddr()
	conn, err := rpcContext.GRPCDial(url)
	if err != nil {
		t.Fatal(err)
	}
	client := serverpb.NewStatusClient(conn)

	response, err := client.SpanStats(context.Background(), &request)
	if err != nil {
		t.Fatal(err)
	}
	if a, e := int(response.RangeCount), ExpectedInitialRangeCount(); a != e {
		t.Errorf("expected %d ranges, found %d", e, a)
	}
}

func gossipForTest(t *testing.T) (*gossip.Gossip, *stop.Stopper) {
	stopper := stop.NewStopper()

	// Setup fake zone config handler.
	config.TestingSetupZoneConfigHook(stopper)

	rpcContext := rpc.NewContext(&base.Context{}, hlc.NewClock(hlc.UnixNano), stopper)
	g := gossip.New(rpcContext, gossip.TestBootstrap)
	// Have to call g.SetNodeID before call g.AddInfo
	g.SetNodeID(roachpb.NodeID(1))
	// Put an empty system config into gossip.
	if err := g.AddInfoProto(gossip.KeySystemConfig,
		&config.SystemConfig{}, 0); err != nil {
		t.Fatal(err)
	}

	// Wait for SystemConfig.
	if err := util.IsTrueWithin(func() bool {
		return g.GetSystemConfig() != nil
	}, 100*time.Millisecond); err != nil {
		t.Fatal(err)
	}

	return g, stopper
}

// startGossip creates and starts a gossip instance.
func startGossip(nodeID roachpb.NodeID, stopper *stop.Stopper, t *testing.T) *Gossip {
	clock := hlc.NewClock(hlc.UnixNano)
	rpcContext := rpc.NewContext(&base.Context{Insecure: true}, clock, stopper)

	addr := util.CreateTestAddr("tcp")
	server := rpc.NewServer(rpcContext)
	tlsConfig, err := rpcContext.GetServerTLSConfig()
	if err != nil {
		t.Fatal(err)
	}
	ln, err := util.ListenAndServe(stopper, server, addr, tlsConfig)
	if err != nil {
		t.Fatal(err)
	}
	g := New(rpcContext, TestBootstrap, stopper)
	g.SetNodeID(nodeID)
	if err := g.SetNodeDescriptor(&roachpb.NodeDescriptor{
		NodeID:  nodeID,
		Address: util.MakeUnresolvedAddr(addr.Network(), addr.String()),
	}); err != nil {
		t.Fatal(err)
	}
	g.start(server, ln.Addr())
	time.Sleep(time.Millisecond)
	return g
}

func gossipForTest(t *testing.T) (*gossip.Gossip, *stop.Stopper) {
	stopper := stop.NewStopper()

	// Setup fake zone config handler.
	config.TestingSetupZoneConfigHook(stopper)

	rpcContext := rpc.NewContext(nil, nil, stopper)
	g := gossip.New(rpcContext, nil, stopper)
	// Have to call g.SetNodeID before call g.AddInfo
	g.SetNodeID(roachpb.NodeID(1))
	// Put an empty system config into gossip.
	if err := g.AddInfoProto(gossip.KeySystemConfig,
		&config.SystemConfig{}, 0); err != nil {
		t.Fatal(err)
	}

	// Wait for SystemConfig.
	util.SucceedsSoon(t, func() error {
		if _, ok := g.GetSystemConfig(); !ok {
			return util.Errorf("expected system config to be set")
		}
		return nil
	})

	return g, stopper
}