add parseTag

Author: robberphex

mse-go-demo/a-server/main.go

@@ -3,12 +3,16 @@ package main
 
 import (
 	"context"
+	"fmt"
+	"io/ioutil"
 	"log"
 	"net/http"
-
-	"google.golang.org/grpc"
+	"os"
+	"regexp"
+	"time"
 
 	b_api_pb "github.com/aliyun/alibabacloud-microservice-demo/mse-go-demo/a-server/proto/b_api"
+	"google.golang.org/grpc"
 )
 
 const (
@@ -17,21 +21,14 @@ const (
 	address = "go-b-service:50051"
 )
 
-var bClient b_api_pb.BServiceClient
-
 func handler(w http.ResponseWriter, r *http.Request) {
+	fmt.Printf("requesting: %v\n", r.URL)
 	ctx := context.Background()
-	bReply, err := bClient.BMethod(ctx, &b_api_pb.BRequest{})
-	if err != nil {
-		w.WriteHeader(500)
-		return
-	}
-	content := "A->" + bReply.GetMessage()
-	w.Write([]byte(content))
-}
+	ctx, cancel := context.WithTimeout(ctx, 5*time.Second)
+	defer cancel()
 
-func main() {
-	conn, err := grpc.Dial(
+	conn, err := grpc.DialContext(
+		ctx,
 		address,
 		grpc.WithInsecure(),
 		grpc.WithBlock(),
@@ -40,8 +37,59 @@ func main() {
 		log.Fatalf("did not connect: %v", err)
 	}
 	defer conn.Close()
-	bClient = b_api_pb.NewBServiceClient(conn)
+	bClient := b_api_pb.NewBServiceClient(conn)
 
+	bReply, err := bClient.BMethod(ctx, &b_api_pb.BRequest{})
+	if err != nil {
+		fmt.Printf("call b-service failed! %v\n", err)
+		log.Printf("call b-service failed! %v", err)
+		w.WriteHeader(500)
+		fmt.Fprint(w, err.Error())
+		return
+	}
+	content := generateMessage("A") + "->" + bReply.GetMessage()
+	fmt.Fprintln(w, content)
+}
+
+func main() {
+	fmt.Println("starting")
 	http.HandleFunc("/", handler)
+
+	fmt.Println("listening")
 	log.Fatal(http.ListenAndServe(port, nil))
 }
+
+func generateMessage(message string) string {
+	tag := parseTag()
+	if tag != "" {
+		message += "-" + tag
+	}
+	hostname, err := os.Hostname()
+	if err == nil {
+		message += "[" + hostname + "]"
+	}
+	return message
+}
+
+func parseTag() string {
+	var re = regexp.MustCompile(`(?m)alicloud\.service\.tag="(?P<tag>.*)"`)
+	bs, err := ioutil.ReadFile("/etc/podinfo/labels")
+	if err != nil {
+		return ""
+	}
+	content := string(bs)
+	result := re.FindStringSubmatch(content)
+
+	groupNames := re.SubexpNames()
+	index := 0
+	for i, name := range groupNames {
+		if name == "tag" {
+			index = i
+			break
+		}
+	}
+	if len(result) <= index {
+		return ""
+	}
+	return result[index]
+}

mse-go-demo/b-server/main.go

@@ -3,8 +3,11 @@ package main
 
 import (
 	"context"
+	"io/ioutil"
 	"log"
 	"net"
+	"os"
+	"regexp"
 
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/reflection"
@@ -21,23 +24,11 @@ const (
 // server is used to implement helloworld.GreeterServer.
 type server struct {
 	b_api_pb.UnimplementedBServiceServer
-
-	cClient c_api_pb.CServiceClient
 }
 
 func (s *server) BMethod(ctx context.Context, req *b_api_pb.BRequest) (*b_api_pb.BReply, error) {
-	cReply, err := s.cClient.CMethod(ctx, &c_api_pb.CRequest{})
-	if err != nil {
-		return nil, err
-	}
-	reply := &b_api_pb.BReply{
-		Message: "B->" + cReply.GetMessage(),
-	}
-	return reply, nil
-}
-
-func main() {
-	conn, err := grpc.Dial(
+	conn, err := grpc.DialContext(
+		ctx,
 		address,
 		grpc.WithInsecure(),
 		grpc.WithBlock(),
@@ -48,16 +39,62 @@ func main() {
 	defer conn.Close()
 	cClient := c_api_pb.NewCServiceClient(conn)
 
+	cReply, err := cClient.CMethod(ctx, &c_api_pb.CRequest{})
+	if err != nil {
+		return nil, err
+	}
+	reply := &b_api_pb.BReply{
+		Message: generateMessage("B") + "->" + cReply.GetMessage(),
+	}
+	return reply, nil
+}
+
+func main() {
 	lis, err := net.Listen("tcp", port)
 	if err != nil {
 		log.Fatalf("failed to listen: %v", err)
 	}
 	s := grpc.NewServer()
-	b_api_pb.RegisterBServiceServer(s, &server{cClient: cClient})
+	b_api_pb.RegisterBServiceServer(s, &server{})
 	log.Printf("server listening at %v", lis.Addr())
 	// Register reflection service on gRPC server.
 	reflection.Register(s)
 	if err := s.Serve(lis); err != nil {
 		log.Fatalf("failed to serve: %v", err)
 	}
 }
+
+func generateMessage(message string) string {
+	tag := parseTag()
+	if tag != "" {
+		message += "-" + tag
+	}
+	hostname, err := os.Hostname()
+	if err == nil {
+		message += "[" + hostname + "]"
+	}
+	return message
+}
+
+func parseTag() string {
+	var re = regexp.MustCompile(`(?m)alicloud\.service\.tag="(?P<tag>.*)"`)
+	bs, err := ioutil.ReadFile("/etc/podinfo/labels")
+	if err != nil {
+		return ""
+	}
+	content := string(bs)
+	result := re.FindStringSubmatch(content)
+
+	groupNames := re.SubexpNames()
+	index := 0
+	for i, name := range groupNames {
+		if name == "tag" {
+			index = i
+			break
+		}
+	}
+	if len(result) <= index {
+		return ""
+	}
+	return result[index]
+}

mse-go-demo/c-server/main.go

@@ -3,8 +3,11 @@ package main
 
 import (
 	"context"
+	"io/ioutil"
 	"log"
 	"net"
+	"os"
+	"regexp"
 
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/reflection"
@@ -23,7 +26,7 @@ type server struct {
 
 func (s *server) CMethod(context.Context, *pb.CRequest) (*pb.CReply, error) {
 	reply := &pb.CReply{
-		Message: "C",
+		Message: generateMessage("C"),
 	}
 	return reply, nil
 }
@@ -42,3 +45,38 @@ func main() {
 		log.Fatalf("failed to serve: %v", err)
 	}
 }
+
+func generateMessage(message string) string {
+	tag := parseTag()
+	if tag != "" {
+		message += "-" + tag
+	}
+	hostname, err := os.Hostname()
+	if err == nil {
+		message += "[" + hostname + "]"
+	}
+	return message
+}
+
+func parseTag() string {
+	var re = regexp.MustCompile(`(?m)alicloud\.service\.tag="(?P<tag>.*)"`)
+	bs, err := ioutil.ReadFile("/etc/podinfo/labels")
+	if err != nil {
+		return ""
+	}
+	content := string(bs)
+	result := re.FindStringSubmatch(content)
+
+	groupNames := re.SubexpNames()
+	index := 0
+	for i, name := range groupNames {
+		if name == "tag" {
+			index = i
+			break
+		}
+	}
+	if len(result) <= index {
+		return ""
+	}
+	return result[index]
+}