interop: add grpclb fallback test (#2994)

interop/grpc_testing/test.pb.go

@@ -56,6 +56,43 @@ func (PayloadType) EnumDescriptor() ([]byte, []int) {
 	return fileDescriptor_e1cda82041fed8bf, []int{0}
 }
 
+// The type of route that a client took to reach a server w.r.t. gRPCLB.
+// The server must fill in "fallback" if it detects that the RPC reached
+// the server via the "gRPCLB fallback" path, and "backend" if it detects
+// that the RPC reached the server via "gRPCLB backend" path (i.e. if it got
+// the address of this server from the gRPCLB server BalanceLoad RPC). Exactly
+// how this detection is done is context and server dependant.
+type GrpclbRouteType int32
+
+const (
+	// Server didn't detect the route that a client took to reach it.
+	GrpclbRouteType_GRPCLB_ROUTE_TYPE_UNKNOWN GrpclbRouteType = 0
+	// Indicates that a client reached a server via gRPCLB fallback.
+	GrpclbRouteType_GRPCLB_ROUTE_TYPE_FALLBACK GrpclbRouteType = 1
+	// Indicates that a client reached a server as a gRPCLB-given backend.
+	GrpclbRouteType_GRPCLB_ROUTE_TYPE_BACKEND GrpclbRouteType = 2
+)
+
+var GrpclbRouteType_name = map[int32]string{
+	0: "GRPCLB_ROUTE_TYPE_UNKNOWN",
+	1: "GRPCLB_ROUTE_TYPE_FALLBACK",
+	2: "GRPCLB_ROUTE_TYPE_BACKEND",
+}
+
+var GrpclbRouteType_value = map[string]int32{
+	"GRPCLB_ROUTE_TYPE_UNKNOWN":  0,
+	"GRPCLB_ROUTE_TYPE_FALLBACK": 1,
+	"GRPCLB_ROUTE_TYPE_BACKEND":  2,
+}
+
+func (x GrpclbRouteType) String() string {
+	return proto.EnumName(GrpclbRouteType_name, int32(x))
+}
+
+func (GrpclbRouteType) EnumDescriptor() ([]byte, []int) {
+	return fileDescriptor_e1cda82041fed8bf, []int{1}
+}
+
 type Empty struct {
 	XXX_NoUnkeyedLiteral struct{} `json:"-"`
 	XXX_unrecognized     []byte   `json:"-"`
@@ -204,6 +241,8 @@ type SimpleRequest struct {
 	ResponseStatus *EchoStatus `protobuf:"bytes,7,opt,name=response_status,json=responseStatus,proto3" json:"response_status,omitempty"`
 	// Whether SimpleResponse should include server_id.
 	FillServerId bool `protobuf:"varint,9,opt,name=fill_server_id,json=fillServerId,proto3" json:"fill_server_id,omitempty"`
+	// Whether SimpleResponse should include grpclb_route_type.
+	FillGrpclbRouteType  bool     `protobuf:"varint,10,opt,name=fill_grpclb_route_type,json=fillGrpclbRouteType,proto3" json:"fill_grpclb_route_type,omitempty"`
 	XXX_NoUnkeyedLiteral struct{} `json:"-"`
 	XXX_unrecognized     []byte   `json:"-"`
 	XXX_sizecache        int32    `json:"-"`
@@ -283,6 +322,13 @@ func (m *SimpleRequest) GetFillServerId() bool {
 	return false
 }
 
+func (m *SimpleRequest) GetFillGrpclbRouteType() bool {
+	if m != nil {
+		return m.FillGrpclbRouteType
+	}
+	return false
+}
+
 // Unary response, as configured by the request.
 type SimpleResponse struct {
 	// Payload to increase message size.
@@ -295,6 +341,8 @@ type SimpleResponse struct {
 	// Server ID. This must be unique among different server instances,
 	// but the same across all RPC's made to a particular server instance.
 	ServerId string `protobuf:"bytes,4,opt,name=server_id,json=serverId,proto3" json:"server_id,omitempty"`
+	// gRPCLB Path.
+	GrpclbRouteType      GrpclbRouteType `protobuf:"varint,5,opt,name=grpclb_route_type,json=grpclbRouteType,proto3,enum=grpc.testing.GrpclbRouteType" json:"grpclb_route_type,omitempty"`
 	XXX_NoUnkeyedLiteral struct{}        `json:"-"`
 	XXX_unrecognized     []byte          `json:"-"`
 	XXX_sizecache        int32           `json:"-"`
@@ -353,6 +401,13 @@ func (m *SimpleResponse) GetServerId() string {
 	return ""
 }
 
+func (m *SimpleResponse) GetGrpclbRouteType() GrpclbRouteType {
+	if m != nil {
+		return m.GrpclbRouteType
+	}
+	return GrpclbRouteType_GRPCLB_ROUTE_TYPE_UNKNOWN
+}
+
 // Client-streaming request.
 type StreamingInputCallRequest struct {
 	// Optional input payload sent along with the request.
@@ -601,6 +656,7 @@ func (m *StreamingOutputCallResponse) GetPayload() *Payload {
 
 func init() {
 	proto.RegisterEnum("grpc.testing.PayloadType", PayloadType_name, PayloadType_value)
+	proto.RegisterEnum("grpc.testing.GrpclbRouteType", GrpclbRouteType_name, GrpclbRouteType_value)
 	proto.RegisterType((*Empty)(nil), "grpc.testing.Empty")
 	proto.RegisterType((*Payload)(nil), "grpc.testing.Payload")
 	proto.RegisterType((*EchoStatus)(nil), "grpc.testing.EchoStatus")
@@ -616,51 +672,58 @@ func init() {
 func init() { proto.RegisterFile("grpc_testing/test.proto", fileDescriptor_e1cda82041fed8bf) }
 
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+	0xf2, 0x42, 0xd0, 0xbd, 0x83, 0x5d, 0xfe, 0xe7, 0x01, 0xc8, 0xb0, 0xd6, 0x7f, 0x02, 0x32, 0x01,
+	0x2d, 0x6f, 0x31, 0xfa, 0xfb, 0x9e, 0x14, 0x8b, 0xaf, 0x46, 0x59, 0xfe, 0x36, 0x30, 0x2c, 0x25,
+	0xb3, 0x52, 0x85, 0xb3, 0xc0, 0xb2, 0x4e, 0x03, 0xd7, 0x22, 0x1f, 0x7e, 0x18, 0x27, 0x59, 0xe0,
+	0xac, 0x0a, 0xaf, 0xb1, 0x75, 0xfd, 0x13, 0x4a, 0xd5, 0x34, 0xf8, 0x45, 0xb3, 0xf9, 0x0d, 0x8e,
+	0x88, 0x4d, 0xc9, 0x30, 0x9e, 0xa2, 0x17, 0xb0, 0x3d, 0x67, 0x7f, 0xdc, 0x34, 0x5d, 0xad, 0xf3,
+	0x5f, 0x34, 0xc7, 0x5f, 0x03, 0x00, 0x00, 0xff, 0xff, 0xc3, 0xf6, 0xdc, 0x4c, 0xec, 0x08, 0x00,
+	0x00,
 }
 
 // Reference imports to suppress errors if they are not otherwise used.

interop/grpc_testing/test.proto

@@ -47,6 +47,21 @@ message EchoStatus {
   string message = 2;
 }
 
+// The type of route that a client took to reach a server w.r.t. gRPCLB.
+// The server must fill in "fallback" if it detects that the RPC reached
+// the server via the "gRPCLB fallback" path, and "backend" if it detects
+// that the RPC reached the server via "gRPCLB backend" path (i.e. if it got
+// the address of this server from the gRPCLB server BalanceLoad RPC). Exactly
+// how this detection is done is context and server dependant.
+enum GrpclbRouteType {
+  // Server didn't detect the route that a client took to reach it.
+  GRPCLB_ROUTE_TYPE_UNKNOWN = 0;
+  // Indicates that a client reached a server via gRPCLB fallback.
+  GRPCLB_ROUTE_TYPE_FALLBACK = 1;
+  // Indicates that a client reached a server as a gRPCLB-given backend.
+  GRPCLB_ROUTE_TYPE_BACKEND = 2;
+}
+
 // Unary request.
 message SimpleRequest {
   // Desired payload type in the response from the server.
@@ -71,6 +86,9 @@ message SimpleRequest {
 
   // Whether SimpleResponse should include server_id.
   bool fill_server_id = 9;
+
+  // Whether SimpleResponse should include grpclb_route_type.
+  bool fill_grpclb_route_type = 10;
 }
 
 // Unary response, as configured by the request.
@@ -88,6 +106,9 @@ message SimpleResponse {
   // Server ID. This must be unique among different server instances,
   // but the same across all RPC's made to a particular server instance.
   string server_id = 4;
+
+  // gRPCLB Path.
+  GrpclbRouteType grpclb_route_type = 5;
 }
 
 // Client-streaming request.

interop/grpclb_fallback/client.go

@@ -0,0 +1,224 @@
+// +build !appengine
+// +build go1.11
+
+/*
+ *
+ * Copyright 2019 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 main
+
+import (
+	"context"
+	"flag"
+	"log"
+	"net"
+	"os"
+	"os/exec"
+	"syscall"
+	"time"
+
+	"golang.org/x/sys/unix"
+	"google.golang.org/grpc"
+	_ "google.golang.org/grpc/balancer/grpclb"
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/credentials/alts"
+	"google.golang.org/grpc/credentials/google"
+	testpb "google.golang.org/grpc/interop/grpc_testing"
+)
+
+var (
+	customCredentialsType         = flag.String("custom_credentials_type", "", "Client creds to use")
+	serverURI                     = flag.String("server_uri", "dns:///staging-grpc-directpath-fallback-test.googleapis.com:443", "The server host name")
+	unrouteLBAndBackendAddrsCmd   = flag.String("unroute_lb_and_backend_addrs_cmd", "", "Command to make LB and backend address unroutable")
+	blackholeLBAndBackendAddrsCmd = flag.String("blackhole_lb_and_backend_addrs_cmd", "", "Command to make LB and backend addresses blackholed")
+	testCase                      = flag.String("test_case", "",
+		`Configure different test cases. Valid options are:
+        fast_fallback_before_startup : LB/backend connections fail fast before RPC's have been made;
+        fast_fallback_after_startup : LB/backend connections fail fast after RPC's have been made;
+        slow_fallback_before_startup : LB/backend connections black hole before RPC's have been made;
+        slow_fallback_after_startup : LB/backend connections black hole after RPC's have been made;`)
+	infoLog  = log.New(os.Stderr, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)
+	errorLog = log.New(os.Stderr, "ERROR: ", log.Ldate|log.Ltime|log.Lshortfile)
+)
+
+func doRPCAndGetPath(client testpb.TestServiceClient, timeout time.Duration) testpb.GrpclbRouteType {
+	infoLog.Printf("doRPCAndGetPath timeout:%v\n", timeout)
+	ctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+	req := &testpb.SimpleRequest{
+		FillGrpclbRouteType: true,
+	}
+	reply, err := client.UnaryCall(ctx, req)
+	if err != nil {
+		infoLog.Printf("doRPCAndGetPath error:%v\n", err)
+		return testpb.GrpclbRouteType_GRPCLB_ROUTE_TYPE_UNKNOWN
+	}
+	g := reply.GetGrpclbRouteType()
+	infoLog.Printf("doRPCAndGetPath got grpclb route type: %v\n", g)
+	if g != testpb.GrpclbRouteType_GRPCLB_ROUTE_TYPE_FALLBACK && g != testpb.GrpclbRouteType_GRPCLB_ROUTE_TYPE_BACKEND {
+		errorLog.Fatalf("Expected grpclb route type to be either backend or fallback; got: %d", g)
+	}
+	return g
+}
+
+func dialTCPUserTimeout(ctx context.Context, addr string) (net.Conn, error) {
+	control := func(network, address string, c syscall.RawConn) error {
+		var syscallErr error
+		controlErr := c.Control(func(fd uintptr) {
+			syscallErr = syscall.SetsockoptInt(int(fd), syscall.IPPROTO_TCP, unix.TCP_USER_TIMEOUT, 20000)
+		})
+		if syscallErr != nil {
+			errorLog.Fatalf("syscall error setting sockopt TCP_USER_TIMEOUT: %v", syscallErr)
+		}
+		if controlErr != nil {
+			errorLog.Fatalf("control error setting sockopt TCP_USER_TIMEOUT: %v", syscallErr)
+		}
+		return nil
+	}
+	d := &net.Dialer{
+		Control: control,
+	}
+	return d.DialContext(ctx, "tcp", addr)
+}
+
+func createTestConn() *grpc.ClientConn {
+	opts := []grpc.DialOption{
+		grpc.WithContextDialer(dialTCPUserTimeout),
+		grpc.WithBlock(),
+	}
+	switch *customCredentialsType {
+	case "tls":
+		creds := credentials.NewClientTLSFromCert(nil, "")
+		opts = append(opts, grpc.WithTransportCredentials(creds))
+	case "alts":
+		creds := alts.NewClientCreds(alts.DefaultClientOptions())
+		opts = append(opts, grpc.WithTransportCredentials(creds))
+	case "google_default_credentials":
+		opts = append(opts, grpc.WithCredentialsBundle(google.NewDefaultCredentials()))
+	case "compute_engine_channel_creds":
+		opts = append(opts, grpc.WithCredentialsBundle(google.NewComputeEngineCredentials()))
+	default:
+		errorLog.Fatalf("Invalid --custom_credentials_type:%v", *customCredentialsType)
+	}
+	conn, err := grpc.Dial(*serverURI, opts...)
+	if err != nil {
+		errorLog.Fatalf("Fail to dial: %v", err)
+	}
+	return conn
+}
+
+func runCmd(command string) {
+	infoLog.Printf("Running cmd:|%v|\n", command)
+	if err := exec.Command("bash", "-c", command).Run(); err != nil {
+		errorLog.Fatalf("error running cmd:|%v| : %v", command, err)
+	}
+}
+
+func waitForFallbackAndDoRPCs(client testpb.TestServiceClient, fallbackDeadline time.Time) {
+	fallbackRetryCount := 0
+	fellBack := false
+	for time.Now().Before(fallbackDeadline) {
+		g := doRPCAndGetPath(client, 1*time.Second)
+		if g == testpb.GrpclbRouteType_GRPCLB_ROUTE_TYPE_FALLBACK {
+			infoLog.Println("Made one successul RPC to a fallback. Now expect the same for the rest.")
+			fellBack = true
+			break
+		} else if g == testpb.GrpclbRouteType_GRPCLB_ROUTE_TYPE_BACKEND {
+			errorLog.Fatalf("Got RPC type backend. This suggests an error in test implementation")
+		} else {
+			infoLog.Println("Retryable RPC failure on iteration:", fallbackRetryCount)
+		}
+		fallbackRetryCount++
+	}
+	if !fellBack {
+		infoLog.Fatalf("Didn't fall back before deadline: %v\n", fallbackDeadline)
+	}
+	for i := 0; i < 30; i++ {
+		if g := doRPCAndGetPath(client, 20*time.Second); g != testpb.GrpclbRouteType_GRPCLB_ROUTE_TYPE_FALLBACK {
+			errorLog.Fatalf("Expected RPC to take grpclb route type FALLBACK. Got: %v", g)
+		}
+		time.Sleep(time.Second)
+	}
+}
+
+func doFastFallbackBeforeStartup() {
+	runCmd(*unrouteLBAndBackendAddrsCmd)
+	fallbackDeadline := time.Now().Add(5 * time.Second)
+	conn := createTestConn()
+	defer conn.Close()
+	client := testpb.NewTestServiceClient(conn)
+	waitForFallbackAndDoRPCs(client, fallbackDeadline)
+}
+
+func doSlowFallbackBeforeStartup() {
+	runCmd(*blackholeLBAndBackendAddrsCmd)
+	fallbackDeadline := time.Now().Add(20 * time.Second)
+	conn := createTestConn()
+	defer conn.Close()
+	client := testpb.NewTestServiceClient(conn)
+	waitForFallbackAndDoRPCs(client, fallbackDeadline)
+}
+
+func doFastFallbackAfterStartup() {
+	conn := createTestConn()
+	defer conn.Close()
+	client := testpb.NewTestServiceClient(conn)
+	if g := doRPCAndGetPath(client, 20*time.Second); g != testpb.GrpclbRouteType_GRPCLB_ROUTE_TYPE_BACKEND {
+		errorLog.Fatalf("Expected RPC to take grpclb route type BACKEND. Got: %v", g)
+	}
+	runCmd(*unrouteLBAndBackendAddrsCmd)
+	fallbackDeadline := time.Now().Add(40 * time.Second)
+	waitForFallbackAndDoRPCs(client, fallbackDeadline)
+}
+
+func doSlowFallbackAfterStartup() {
+	conn := createTestConn()
+	defer conn.Close()
+	client := testpb.NewTestServiceClient(conn)
+	if g := doRPCAndGetPath(client, 20*time.Second); g != testpb.GrpclbRouteType_GRPCLB_ROUTE_TYPE_BACKEND {
+		errorLog.Fatalf("Expected RPC to take grpclb route type BACKEND. Got: %v", g)
+	}
+	runCmd(*blackholeLBAndBackendAddrsCmd)
+	fallbackDeadline := time.Now().Add(40 * time.Second)
+	waitForFallbackAndDoRPCs(client, fallbackDeadline)
+}
+
+func main() {
+	flag.Parse()
+	if len(*unrouteLBAndBackendAddrsCmd) == 0 {
+		errorLog.Fatalf("--unroute_lb_and_backend_addrs_cmd unset")
+	}
+	if len(*blackholeLBAndBackendAddrsCmd) == 0 {
+		errorLog.Fatalf("--blackhole_lb_and_backend_addrs_cmd unset")
+	}
+	switch *testCase {
+	case "fast_fallback_before_startup":
+		doFastFallbackBeforeStartup()
+		log.Printf("FastFallbackBeforeStartup done!\n")
+	case "fast_fallback_after_startup":
+		doFastFallbackAfterStartup()
+		log.Printf("FastFallbackAfterStartup done!\n")
+	case "slow_fallback_before_startup":
+		doSlowFallbackBeforeStartup()
+		log.Printf("SlowFallbackBeforeStartup done!\n")
+	case "slow_fallback_after_startup":
+		doSlowFallbackAfterStartup()
+		log.Printf("SlowFallbackAfterStartup done!\n")
+	default:
+		errorLog.Fatalf("Unsupported test case: %v", *testCase)
+	}
+}