/
grpclb_test.go
1708 lines (1550 loc) · 53.8 KB
/
grpclb_test.go
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/*
*
* Copyright 2016 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package grpclb
import (
"context"
"errors"
"fmt"
"io"
"net"
"strconv"
"strings"
"sync"
"sync/atomic"
"testing"
"time"
"github.com/google/go-cmp/cmp"
"github.com/google/go-cmp/cmp/cmpopts"
"google.golang.org/grpc"
"google.golang.org/grpc/balancer"
grpclbstate "google.golang.org/grpc/balancer/grpclb/state"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/credentials"
"google.golang.org/grpc/internal/grpctest"
"google.golang.org/grpc/internal/testutils"
"google.golang.org/grpc/metadata"
"google.golang.org/grpc/peer"
"google.golang.org/grpc/resolver"
"google.golang.org/grpc/resolver/manual"
"google.golang.org/grpc/status"
durationpb "github.com/golang/protobuf/ptypes/duration"
lbgrpc "google.golang.org/grpc/balancer/grpclb/grpc_lb_v1"
lbpb "google.golang.org/grpc/balancer/grpclb/grpc_lb_v1"
testpb "google.golang.org/grpc/test/grpc_testing"
)
var (
lbServerName = "lb.server.com"
beServerName = "backends.com"
lbToken = "iamatoken"
// Resolver replaces localhost with fakeName in Next().
// Dialer replaces fakeName with localhost when dialing.
// This will test that custom dialer is passed from Dial to grpclb.
fakeName = "fake.Name"
)
const (
defaultTestTimeout = 10 * time.Second
defaultTestShortTimeout = 10 * time.Millisecond
testUserAgent = "test-user-agent"
grpclbConfig = `{"loadBalancingConfig": [{"grpclb": {}}]}`
)
type s struct {
grpctest.Tester
}
func Test(t *testing.T) {
grpctest.RunSubTests(t, s{})
}
type serverNameCheckCreds struct {
mu sync.Mutex
sn string
}
func (c *serverNameCheckCreds) ServerHandshake(rawConn net.Conn) (net.Conn, credentials.AuthInfo, error) {
if _, err := io.WriteString(rawConn, c.sn); err != nil {
fmt.Printf("Failed to write the server name %s to the client %v", c.sn, err)
return nil, nil, err
}
return rawConn, nil, nil
}
func (c *serverNameCheckCreds) ClientHandshake(ctx context.Context, authority string, rawConn net.Conn) (net.Conn, credentials.AuthInfo, error) {
c.mu.Lock()
defer c.mu.Unlock()
b := make([]byte, len(authority))
errCh := make(chan error, 1)
go func() {
_, err := rawConn.Read(b)
errCh <- err
}()
select {
case err := <-errCh:
if err != nil {
fmt.Printf("test-creds: failed to read expected authority name from the server: %v\n", err)
return nil, nil, err
}
case <-ctx.Done():
return nil, nil, ctx.Err()
}
if authority != string(b) {
fmt.Printf("test-creds: got authority from ClientConn %q, expected by server %q\n", authority, string(b))
return nil, nil, errors.New("received unexpected server name")
}
return rawConn, nil, nil
}
func (c *serverNameCheckCreds) Info() credentials.ProtocolInfo {
return credentials.ProtocolInfo{}
}
func (c *serverNameCheckCreds) Clone() credentials.TransportCredentials {
return &serverNameCheckCreds{}
}
func (c *serverNameCheckCreds) OverrideServerName(s string) error {
return nil
}
// fakeNameDialer replaces fakeName with localhost when dialing.
// This will test that custom dialer is passed from Dial to grpclb.
func fakeNameDialer(ctx context.Context, addr string) (net.Conn, error) {
addr = strings.Replace(addr, fakeName, "localhost", 1)
return (&net.Dialer{}).DialContext(ctx, "tcp", addr)
}
// merge merges the new client stats into current stats.
//
// It's a test-only method. rpcStats is defined in grpclb_picker.
func (s *rpcStats) merge(cs *lbpb.ClientStats) {
atomic.AddInt64(&s.numCallsStarted, cs.NumCallsStarted)
atomic.AddInt64(&s.numCallsFinished, cs.NumCallsFinished)
atomic.AddInt64(&s.numCallsFinishedWithClientFailedToSend, cs.NumCallsFinishedWithClientFailedToSend)
atomic.AddInt64(&s.numCallsFinishedKnownReceived, cs.NumCallsFinishedKnownReceived)
s.mu.Lock()
for _, perToken := range cs.CallsFinishedWithDrop {
s.numCallsDropped[perToken.LoadBalanceToken] += perToken.NumCalls
}
s.mu.Unlock()
}
func atomicEqual(a, b *int64) bool {
return atomic.LoadInt64(a) == atomic.LoadInt64(b)
}
// equal compares two rpcStats.
//
// It's a test-only method. rpcStats is defined in grpclb_picker.
func (s *rpcStats) equal(o *rpcStats) bool {
if !atomicEqual(&s.numCallsStarted, &o.numCallsStarted) {
return false
}
if !atomicEqual(&s.numCallsFinished, &o.numCallsFinished) {
return false
}
if !atomicEqual(&s.numCallsFinishedWithClientFailedToSend, &o.numCallsFinishedWithClientFailedToSend) {
return false
}
if !atomicEqual(&s.numCallsFinishedKnownReceived, &o.numCallsFinishedKnownReceived) {
return false
}
s.mu.Lock()
defer s.mu.Unlock()
o.mu.Lock()
defer o.mu.Unlock()
return cmp.Equal(s.numCallsDropped, o.numCallsDropped, cmpopts.EquateEmpty())
}
func (s *rpcStats) String() string {
s.mu.Lock()
defer s.mu.Unlock()
return fmt.Sprintf("Started: %v, Finished: %v, FinishedWithClientFailedToSend: %v, FinishedKnownReceived: %v, Dropped: %v",
atomic.LoadInt64(&s.numCallsStarted),
atomic.LoadInt64(&s.numCallsFinished),
atomic.LoadInt64(&s.numCallsFinishedWithClientFailedToSend),
atomic.LoadInt64(&s.numCallsFinishedKnownReceived),
s.numCallsDropped)
}
type remoteBalancer struct {
lbgrpc.UnimplementedLoadBalancerServer
sls chan *lbpb.ServerList
statsDura time.Duration
done chan struct{}
stats *rpcStats
statsChan chan *lbpb.ClientStats
fbChan chan struct{}
balanceLoadCh chan struct{} // notify successful invocation of BalanceLoad
wantUserAgent string // expected user-agent in metadata of BalancerLoad
wantServerName string // expected server name in InitialLoadBalanceRequest
}
func newRemoteBalancer(wantUserAgent, wantServerName string, statsChan chan *lbpb.ClientStats) *remoteBalancer {
return &remoteBalancer{
sls: make(chan *lbpb.ServerList, 1),
done: make(chan struct{}),
stats: newRPCStats(),
statsChan: statsChan,
fbChan: make(chan struct{}),
balanceLoadCh: make(chan struct{}, 1),
wantUserAgent: wantUserAgent,
wantServerName: wantServerName,
}
}
func (b *remoteBalancer) stop() {
close(b.sls)
close(b.done)
}
func (b *remoteBalancer) fallbackNow() {
b.fbChan <- struct{}{}
}
func (b *remoteBalancer) updateServerName(name string) {
b.wantServerName = name
}
func (b *remoteBalancer) BalanceLoad(stream lbgrpc.LoadBalancer_BalanceLoadServer) error {
md, ok := metadata.FromIncomingContext(stream.Context())
if !ok {
return status.Error(codes.Internal, "failed to receive metadata")
}
if b.wantUserAgent != "" {
if ua := md["user-agent"]; len(ua) == 0 || !strings.HasPrefix(ua[0], b.wantUserAgent) {
return status.Errorf(codes.InvalidArgument, "received unexpected user-agent: %v, want prefix %q", ua, b.wantUserAgent)
}
}
req, err := stream.Recv()
if err != nil {
return err
}
initReq := req.GetInitialRequest()
if initReq.Name != b.wantServerName {
return status.Errorf(codes.InvalidArgument, "invalid service name: %q, want: %q", initReq.Name, b.wantServerName)
}
b.balanceLoadCh <- struct{}{}
resp := &lbpb.LoadBalanceResponse{
LoadBalanceResponseType: &lbpb.LoadBalanceResponse_InitialResponse{
InitialResponse: &lbpb.InitialLoadBalanceResponse{
ClientStatsReportInterval: &durationpb.Duration{
Seconds: int64(b.statsDura.Seconds()),
Nanos: int32(b.statsDura.Nanoseconds() - int64(b.statsDura.Seconds())*1e9),
},
},
},
}
if err := stream.Send(resp); err != nil {
return err
}
go func() {
for {
req, err := stream.Recv()
if err != nil {
return
}
b.stats.merge(req.GetClientStats())
if b.statsChan != nil && req.GetClientStats() != nil {
b.statsChan <- req.GetClientStats()
}
}
}()
for {
select {
case v := <-b.sls:
resp = &lbpb.LoadBalanceResponse{
LoadBalanceResponseType: &lbpb.LoadBalanceResponse_ServerList{
ServerList: v,
},
}
case <-b.fbChan:
resp = &lbpb.LoadBalanceResponse{
LoadBalanceResponseType: &lbpb.LoadBalanceResponse_FallbackResponse{
FallbackResponse: &lbpb.FallbackResponse{},
},
}
case <-stream.Context().Done():
return stream.Context().Err()
}
if err := stream.Send(resp); err != nil {
return err
}
}
}
type testServer struct {
testpb.UnimplementedTestServiceServer
addr string
fallback bool
}
const testmdkey = "testmd"
func (s *testServer) EmptyCall(ctx context.Context, in *testpb.Empty) (*testpb.Empty, error) {
md, ok := metadata.FromIncomingContext(ctx)
if !ok {
return nil, status.Error(codes.Internal, "failed to receive metadata")
}
if !s.fallback && (md == nil || len(md["lb-token"]) == 0 || md["lb-token"][0] != lbToken) {
return nil, status.Errorf(codes.Internal, "received unexpected metadata: %v", md)
}
grpc.SetTrailer(ctx, metadata.Pairs(testmdkey, s.addr))
return &testpb.Empty{}, nil
}
func (s *testServer) FullDuplexCall(stream testpb.TestService_FullDuplexCallServer) error {
return nil
}
func startBackends(sn string, fallback bool, lis ...net.Listener) (servers []*grpc.Server) {
for _, l := range lis {
creds := &serverNameCheckCreds{
sn: sn,
}
s := grpc.NewServer(grpc.Creds(creds))
testpb.RegisterTestServiceServer(s, &testServer{addr: l.Addr().String(), fallback: fallback})
servers = append(servers, s)
go func(s *grpc.Server, l net.Listener) {
s.Serve(l)
}(s, l)
}
return
}
func stopBackends(servers []*grpc.Server) {
for _, s := range servers {
s.Stop()
}
}
type testServers struct {
lbAddr string
ls *remoteBalancer
lb *grpc.Server
backends []*grpc.Server
beIPs []net.IP
bePorts []int
lbListener net.Listener
beListeners []net.Listener
}
func startBackendsAndRemoteLoadBalancer(numberOfBackends int, customUserAgent string, statsChan chan *lbpb.ClientStats) (tss *testServers, cleanup func(), err error) {
var (
beListeners []net.Listener
ls *remoteBalancer
lb *grpc.Server
beIPs []net.IP
bePorts []int
)
for i := 0; i < numberOfBackends; i++ {
// Start a backend.
beLis, e := net.Listen("tcp", "localhost:0")
if e != nil {
err = fmt.Errorf("failed to listen %v", err)
return
}
beIPs = append(beIPs, beLis.Addr().(*net.TCPAddr).IP)
bePorts = append(bePorts, beLis.Addr().(*net.TCPAddr).Port)
beListeners = append(beListeners, newRestartableListener(beLis))
}
backends := startBackends(beServerName, false, beListeners...)
// Start a load balancer.
lbLis, err := net.Listen("tcp", "localhost:0")
if err != nil {
err = fmt.Errorf("failed to create the listener for the load balancer %v", err)
return
}
lbLis = newRestartableListener(lbLis)
lbCreds := &serverNameCheckCreds{
sn: lbServerName,
}
lb = grpc.NewServer(grpc.Creds(lbCreds))
ls = newRemoteBalancer(customUserAgent, beServerName, statsChan)
lbgrpc.RegisterLoadBalancerServer(lb, ls)
go func() {
lb.Serve(lbLis)
}()
tss = &testServers{
lbAddr: net.JoinHostPort(fakeName, strconv.Itoa(lbLis.Addr().(*net.TCPAddr).Port)),
ls: ls,
lb: lb,
backends: backends,
beIPs: beIPs,
bePorts: bePorts,
lbListener: lbLis,
beListeners: beListeners,
}
cleanup = func() {
defer stopBackends(backends)
defer func() {
ls.stop()
lb.Stop()
}()
}
return
}
func (s) TestGRPCLB(t *testing.T) {
r := manual.NewBuilderWithScheme("whatever")
tss, cleanup, err := startBackendsAndRemoteLoadBalancer(1, testUserAgent, nil)
if err != nil {
t.Fatalf("failed to create new load balancer: %v", err)
}
defer cleanup()
tss.ls.sls <- &lbpb.ServerList{
Servers: []*lbpb.Server{
{
IpAddress: tss.beIPs[0],
Port: int32(tss.bePorts[0]),
LoadBalanceToken: lbToken,
},
},
}
cc, err := grpc.Dial(r.Scheme()+":///"+beServerName,
grpc.WithResolvers(r),
grpc.WithTransportCredentials(&serverNameCheckCreds{}),
grpc.WithContextDialer(fakeNameDialer),
grpc.WithUserAgent(testUserAgent))
if err != nil {
t.Fatalf("Failed to dial to the backend %v", err)
}
defer cc.Close()
testC := testpb.NewTestServiceClient(cc)
rs := grpclbstate.Set(resolver.State{ServiceConfig: r.CC.ParseServiceConfig(grpclbConfig)},
&grpclbstate.State{BalancerAddresses: []resolver.Address{{
Addr: tss.lbAddr,
ServerName: lbServerName,
}}})
r.UpdateState(rs)
ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
defer cancel()
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}); err != nil {
t.Fatalf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
}
// The remote balancer sends response with duplicates to grpclb client.
func (s) TestGRPCLBWeighted(t *testing.T) {
r := manual.NewBuilderWithScheme("whatever")
tss, cleanup, err := startBackendsAndRemoteLoadBalancer(2, "", nil)
if err != nil {
t.Fatalf("failed to create new load balancer: %v", err)
}
defer cleanup()
beServers := []*lbpb.Server{{
IpAddress: tss.beIPs[0],
Port: int32(tss.bePorts[0]),
LoadBalanceToken: lbToken,
}, {
IpAddress: tss.beIPs[1],
Port: int32(tss.bePorts[1]),
LoadBalanceToken: lbToken,
}}
portsToIndex := make(map[int]int)
for i := range beServers {
portsToIndex[tss.bePorts[i]] = i
}
cc, err := grpc.Dial(r.Scheme()+":///"+beServerName,
grpc.WithResolvers(r),
grpc.WithTransportCredentials(&serverNameCheckCreds{}),
grpc.WithContextDialer(fakeNameDialer))
if err != nil {
t.Fatalf("Failed to dial to the backend %v", err)
}
defer cc.Close()
testC := testpb.NewTestServiceClient(cc)
rs := grpclbstate.Set(resolver.State{ServiceConfig: r.CC.ParseServiceConfig(grpclbConfig)},
&grpclbstate.State{BalancerAddresses: []resolver.Address{{
Addr: tss.lbAddr,
ServerName: lbServerName,
}}})
r.UpdateState(rs)
ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
defer cancel()
sequences := []string{"00101", "00011"}
for _, seq := range sequences {
var (
bes []*lbpb.Server
p peer.Peer
result string
)
for _, s := range seq {
bes = append(bes, beServers[s-'0'])
}
tss.ls.sls <- &lbpb.ServerList{Servers: bes}
for i := 0; i < 1000; i++ {
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Fatalf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
result += strconv.Itoa(portsToIndex[p.Addr.(*net.TCPAddr).Port])
}
// The generated result will be in format of "0010100101".
if !strings.Contains(result, strings.Repeat(seq, 2)) {
t.Errorf("got result sequence %q, want patten %q", result, seq)
}
}
}
func (s) TestDropRequest(t *testing.T) {
r := manual.NewBuilderWithScheme("whatever")
tss, cleanup, err := startBackendsAndRemoteLoadBalancer(2, "", nil)
if err != nil {
t.Fatalf("failed to create new load balancer: %v", err)
}
defer cleanup()
tss.ls.sls <- &lbpb.ServerList{
Servers: []*lbpb.Server{{
IpAddress: tss.beIPs[0],
Port: int32(tss.bePorts[0]),
LoadBalanceToken: lbToken,
Drop: false,
}, {
IpAddress: tss.beIPs[1],
Port: int32(tss.bePorts[1]),
LoadBalanceToken: lbToken,
Drop: false,
}, {
Drop: true,
}},
}
cc, err := grpc.Dial(r.Scheme()+":///"+beServerName,
grpc.WithResolvers(r),
grpc.WithTransportCredentials(&serverNameCheckCreds{}),
grpc.WithContextDialer(fakeNameDialer))
if err != nil {
t.Fatalf("Failed to dial to the backend %v", err)
}
defer cc.Close()
testC := testpb.NewTestServiceClient(cc)
rs := grpclbstate.Set(resolver.State{ServiceConfig: r.CC.ParseServiceConfig(grpclbConfig)},
&grpclbstate.State{BalancerAddresses: []resolver.Address{{
Addr: tss.lbAddr,
ServerName: lbServerName,
}}})
r.UpdateState(rs)
var (
i int
p peer.Peer
)
const (
// Poll to wait for something to happen. Total timeout 1 second. Sleep 1
// ms each loop, and do at most 1000 loops.
sleepEachLoop = time.Millisecond
loopCount = int(time.Second / sleepEachLoop)
)
ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
defer cancel()
// Make a non-fail-fast RPC and wait for it to succeed.
for i = 0; i < loopCount; i++ {
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err == nil {
break
}
time.Sleep(sleepEachLoop)
}
if i >= loopCount {
t.Fatalf("timeout waiting for the first connection to become ready. EmptyCall(_, _) = _, %v, want _, <nil>", err)
}
// Make RPCs until the peer is different. So we know both connections are
// READY.
for i = 0; i < loopCount; i++ {
var temp peer.Peer
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&temp)); err == nil {
if temp.Addr.(*net.TCPAddr).Port != p.Addr.(*net.TCPAddr).Port {
break
}
}
time.Sleep(sleepEachLoop)
}
if i >= loopCount {
t.Fatalf("timeout waiting for the second connection to become ready")
}
// More RPCs until drop happens. So we know the picker index, and the
// expected behavior of following RPCs.
for i = 0; i < loopCount; i++ {
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true)); status.Code(err) == codes.Unavailable {
break
}
time.Sleep(sleepEachLoop)
}
if i >= loopCount {
t.Fatalf("timeout waiting for drop. EmptyCall(_, _) = _, %v, want _, <Unavailable>", err)
}
select {
case <-ctx.Done():
t.Fatal("timed out", ctx.Err())
default:
}
for _, failfast := range []bool{true, false} {
for i := 0; i < 3; i++ {
// 1st RPCs pick the first item in server list. They should succeed
// since they choose the non-drop-request backend according to the
// round robin policy.
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(!failfast)); err != nil {
t.Errorf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
// 2nd RPCs pick the second item in server list. They should succeed
// since they choose the non-drop-request backend according to the
// round robin policy.
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(!failfast)); err != nil {
t.Errorf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
// 3rd RPCs should fail, because they pick last item in server list,
// with Drop set to true.
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(!failfast)); status.Code(err) != codes.Unavailable {
t.Errorf("%v.EmptyCall(_, _) = _, %v, want _, %s", testC, err, codes.Unavailable)
}
}
}
// Make one more RPC to move the picker index one step further, so it's not
// 0. The following RPCs will test that drop index is not reset. If picker
// index is at 0, we cannot tell whether it's reset or not.
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true)); err != nil {
t.Errorf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
tss.backends[0].Stop()
// This last pick was backend 0. Closing backend 0 doesn't reset drop index
// (for level 1 picking), so the following picks will be (backend1, drop,
// backend1), instead of (backend, backend, drop) if drop index was reset.
time.Sleep(time.Second)
for i := 0; i < 3; i++ {
var p peer.Peer
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Errorf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
if want := tss.bePorts[1]; p.Addr.(*net.TCPAddr).Port != want {
t.Errorf("got peer: %v, want peer port: %v", p.Addr, want)
}
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true)); status.Code(err) != codes.Unavailable {
t.Errorf("%v.EmptyCall(_, _) = _, %v, want _, %s", testC, err, codes.Unavailable)
}
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Errorf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
if want := tss.bePorts[1]; p.Addr.(*net.TCPAddr).Port != want {
t.Errorf("got peer: %v, want peer port: %v", p.Addr, want)
}
}
}
// When the balancer in use disconnects, grpclb should connect to the next address from resolved balancer address list.
func (s) TestBalancerDisconnects(t *testing.T) {
r := manual.NewBuilderWithScheme("whatever")
var (
tests []*testServers
lbs []*grpc.Server
)
for i := 0; i < 2; i++ {
tss, cleanup, err := startBackendsAndRemoteLoadBalancer(1, "", nil)
if err != nil {
t.Fatalf("failed to create new load balancer: %v", err)
}
defer cleanup()
tss.ls.sls <- &lbpb.ServerList{
Servers: []*lbpb.Server{
{
IpAddress: tss.beIPs[0],
Port: int32(tss.bePorts[0]),
LoadBalanceToken: lbToken,
},
},
}
tests = append(tests, tss)
lbs = append(lbs, tss.lb)
}
cc, err := grpc.Dial(r.Scheme()+":///"+beServerName,
grpc.WithResolvers(r),
grpc.WithTransportCredentials(&serverNameCheckCreds{}),
grpc.WithContextDialer(fakeNameDialer))
if err != nil {
t.Fatalf("Failed to dial to the backend %v", err)
}
defer cc.Close()
testC := testpb.NewTestServiceClient(cc)
rs := grpclbstate.Set(resolver.State{ServiceConfig: r.CC.ParseServiceConfig(grpclbConfig)},
&grpclbstate.State{BalancerAddresses: []resolver.Address{
{
Addr: tests[0].lbAddr,
ServerName: lbServerName,
},
{
Addr: tests[1].lbAddr,
ServerName: lbServerName,
},
}})
r.UpdateState(rs)
ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
defer cancel()
var p peer.Peer
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Fatalf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
if p.Addr.(*net.TCPAddr).Port != tests[0].bePorts[0] {
t.Fatalf("got peer: %v, want peer port: %v", p.Addr, tests[0].bePorts[0])
}
lbs[0].Stop()
// Stop balancer[0], balancer[1] should be used by grpclb.
// Check peer address to see if that happened.
for i := 0; i < 1000; i++ {
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Fatalf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
if p.Addr.(*net.TCPAddr).Port == tests[1].bePorts[0] {
return
}
time.Sleep(time.Millisecond)
}
t.Fatalf("No RPC sent to second backend after 1 second")
}
func (s) TestFallback(t *testing.T) {
balancer.Register(newLBBuilderWithFallbackTimeout(100 * time.Millisecond))
defer balancer.Register(newLBBuilder())
r := manual.NewBuilderWithScheme("whatever")
// Start a remote balancer and a backend. Push the backend address to the
// remote balancer.
tss, cleanup, err := startBackendsAndRemoteLoadBalancer(1, "", nil)
if err != nil {
t.Fatalf("failed to create new load balancer: %v", err)
}
defer cleanup()
sl := &lbpb.ServerList{
Servers: []*lbpb.Server{
{
IpAddress: tss.beIPs[0],
Port: int32(tss.bePorts[0]),
LoadBalanceToken: lbToken,
},
},
}
tss.ls.sls <- sl
// Start a standalone backend for fallback.
beLis, err := net.Listen("tcp", "localhost:0")
if err != nil {
t.Fatalf("Failed to listen %v", err)
}
defer beLis.Close()
standaloneBEs := startBackends(beServerName, true, beLis)
defer stopBackends(standaloneBEs)
cc, err := grpc.Dial(r.Scheme()+":///"+beServerName,
grpc.WithResolvers(r),
grpc.WithTransportCredentials(&serverNameCheckCreds{}),
grpc.WithContextDialer(fakeNameDialer))
if err != nil {
t.Fatalf("Failed to dial to the backend %v", err)
}
defer cc.Close()
testC := testpb.NewTestServiceClient(cc)
// Push an update to the resolver with fallback backend address stored in
// the `Addresses` field and an invalid remote balancer address stored in
// attributes, which will cause fallback behavior to be invoked.
rs := resolver.State{
Addresses: []resolver.Address{{Addr: beLis.Addr().String()}},
ServiceConfig: r.CC.ParseServiceConfig(grpclbConfig),
}
rs = grpclbstate.Set(rs, &grpclbstate.State{BalancerAddresses: []resolver.Address{{Addr: "invalid.address", ServerName: lbServerName}}})
r.UpdateState(rs)
// Make an RPC and verify that it got routed to the fallback backend.
ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
defer cancel()
var p peer.Peer
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Fatalf("_.EmptyCall(_, _) = _, %v, want _, <nil>", err)
}
if p.Addr.String() != beLis.Addr().String() {
t.Fatalf("got peer: %v, want peer: %v", p.Addr, beLis.Addr())
}
// Push another update to the resolver, this time with a valid balancer
// address in the attributes field.
rs = resolver.State{
ServiceConfig: r.CC.ParseServiceConfig(grpclbConfig),
Addresses: []resolver.Address{{Addr: beLis.Addr().String()}},
}
rs = grpclbstate.Set(rs, &grpclbstate.State{BalancerAddresses: []resolver.Address{{Addr: tss.lbAddr, ServerName: lbServerName}}})
r.UpdateState(rs)
select {
case <-ctx.Done():
t.Fatalf("timeout when waiting for BalanceLoad RPC to be called on the remote balancer")
case <-tss.ls.balanceLoadCh:
}
// Wait for RPCs to get routed to the backend behind the remote balancer.
var backendUsed bool
for i := 0; i < 1000; i++ {
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Fatalf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
if p.Addr.(*net.TCPAddr).Port == tss.bePorts[0] {
backendUsed = true
break
}
time.Sleep(time.Millisecond)
}
if !backendUsed {
t.Fatalf("No RPC sent to backend behind remote balancer after 1 second")
}
// Close backend and remote balancer connections, should use fallback.
tss.beListeners[0].(*restartableListener).stopPreviousConns()
tss.lbListener.(*restartableListener).stopPreviousConns()
var fallbackUsed bool
for i := 0; i < 2000; i++ {
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
// Because we are hard-closing the connection, above, it's possible
// for the first RPC attempt to be sent on the old connection,
// which will lead to an Unavailable error when it is closed.
// Ignore unavailable errors.
if status.Code(err) != codes.Unavailable {
t.Fatalf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
}
if p.Addr.String() == beLis.Addr().String() {
fallbackUsed = true
break
}
time.Sleep(time.Millisecond)
}
if !fallbackUsed {
t.Fatalf("No RPC sent to fallback after 2 seconds")
}
// Restart backend and remote balancer, should not use fallback backend.
tss.beListeners[0].(*restartableListener).restart()
tss.lbListener.(*restartableListener).restart()
tss.ls.sls <- sl
var backendUsed2 bool
for i := 0; i < 2000; i++ {
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Fatalf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
if p.Addr.(*net.TCPAddr).Port == tss.bePorts[0] {
backendUsed2 = true
break
}
time.Sleep(time.Millisecond)
}
if !backendUsed2 {
t.Fatalf("No RPC sent to backend behind remote balancer after 2 seconds")
}
}
func (s) TestExplicitFallback(t *testing.T) {
r := manual.NewBuilderWithScheme("whatever")
// Start a remote balancer and a backend. Push the backend address to the
// remote balancer.
tss, cleanup, err := startBackendsAndRemoteLoadBalancer(1, "", nil)
if err != nil {
t.Fatalf("failed to create new load balancer: %v", err)
}
defer cleanup()
sl := &lbpb.ServerList{
Servers: []*lbpb.Server{
{
IpAddress: tss.beIPs[0],
Port: int32(tss.bePorts[0]),
LoadBalanceToken: lbToken,
},
},
}
tss.ls.sls <- sl
// Start a standalone backend for fallback.
beLis, err := net.Listen("tcp", "localhost:0")
if err != nil {
t.Fatalf("Failed to listen %v", err)
}
defer beLis.Close()
standaloneBEs := startBackends(beServerName, true, beLis)
defer stopBackends(standaloneBEs)
cc, err := grpc.Dial(r.Scheme()+":///"+beServerName,
grpc.WithResolvers(r),
grpc.WithTransportCredentials(&serverNameCheckCreds{}),
grpc.WithContextDialer(fakeNameDialer))
if err != nil {
t.Fatalf("Failed to dial to the backend %v", err)
}
defer cc.Close()
testC := testpb.NewTestServiceClient(cc)
rs := resolver.State{
Addresses: []resolver.Address{{Addr: beLis.Addr().String()}},
ServiceConfig: r.CC.ParseServiceConfig(grpclbConfig),
}
rs = grpclbstate.Set(rs, &grpclbstate.State{BalancerAddresses: []resolver.Address{{Addr: tss.lbAddr, ServerName: lbServerName}}})
r.UpdateState(rs)
ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
defer cancel()
var p peer.Peer
var backendUsed bool
for i := 0; i < 2000; i++ {
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Fatalf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
if p.Addr.(*net.TCPAddr).Port == tss.bePorts[0] {
backendUsed = true
break
}
time.Sleep(time.Millisecond)
}
if !backendUsed {
t.Fatalf("No RPC sent to backend behind remote balancer after 2 seconds")
}
// Send fallback signal from remote balancer; should use fallback.
tss.ls.fallbackNow()
var fallbackUsed bool
for i := 0; i < 2000; i++ {
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Fatalf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
if p.Addr.String() == beLis.Addr().String() {
fallbackUsed = true
break
}
time.Sleep(time.Millisecond)
}
if !fallbackUsed {
t.Fatalf("No RPC sent to fallback after 2 seconds")
}
// Send another server list; should use backends again.
tss.ls.sls <- sl
backendUsed = false
for i := 0; i < 2000; i++ {
if _, err := testC.EmptyCall(ctx, &testpb.Empty{}, grpc.WaitForReady(true), grpc.Peer(&p)); err != nil {
t.Fatalf("%v.EmptyCall(_, _) = _, %v, want _, <nil>", testC, err)
}
if p.Addr.(*net.TCPAddr).Port == tss.bePorts[0] {
backendUsed = true
break
}
time.Sleep(time.Millisecond)
}
if !backendUsed {
t.Fatalf("No RPC sent to backend behind remote balancer after 2 seconds")
}
}
func (s) TestFallBackWithNoServerAddress(t *testing.T) {
resolveNowCh := testutils.NewChannel()
r := manual.NewBuilderWithScheme("whatever")
r.ResolveNowCallback = func(resolver.ResolveNowOptions) {
ctx, cancel := context.WithTimeout(context.Background(), defaultTestShortTimeout)