74. Integrasi gRPC dengan Envoy Proxy

 1syntax = "proto3";
 2
 3package helloworld;
 4
 5service Greeter {
 6  rpc SayHello (HelloRequest) returns (HelloReply);
 7}
 8
 9message HelloRequest {
10  string name = 1;
11}
12
13message HelloReply {
14  string message = 1;
15}

1protoc --go_out=. --go-grpc_out=. helloworld.proto

 1// server.go
 2package main
 3
 4import (
 5    "context"
 6    "log"
 7    "net"
 8
 9    pb "yourmod/helloworld"
10    "google.golang.org/grpc"
11)
12
13type server struct {
14    pb.UnimplementedGreeterServer
15}
16
17func (s *server) SayHello(ctx context.Context, in *pb.HelloRequest) (*pb.HelloReply, error) {
18    return &pb.HelloReply{Message: "Hello, " + in.Name}, nil
19}
20
21func main() {
22    lis, err := net.Listen("tcp", ":50051")
23    if err != nil {
24        log.Fatalf("failed to listen: %v", err)
25    }
26    s := grpc.NewServer()
27    pb.RegisterGreeterServer(s, &server{})
28    log.Println("gRPC server listening on :50051")
29    s.Serve(lis)
30}

 1static_resources:
 2  listeners:
 3    - name: listener_0
 4      address:
 5        socket_address: { address: 0.0.0.0, port_value: 9901 }
 6      filter_chains:
 7        - filters:
 8            - name: envoy.filters.network.http_connection_manager
 9              typed_config:
10                "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
11                codec_type: AUTO
12                stat_prefix: ingress_http
13                route_config:
14                  name: local_route
15                  virtual_hosts:
16                    - name: backend
17                      domains: ["*"]
18                      routes:
19                        - match: { prefix: "/" }
20                          route: { cluster: greeter_service }
21                http_filters:
22                  - name: envoy.filters.http.router
23    # Envoy will use HTTP/2 to proxy the gRPC calls.
24  clusters:
25    - name: greeter_service
26      connect_timeout: 0.25s
27      type: logical_dns
28      lb_policy: round_robin
29      http2_protocol_options: {} # Enables HTTP2 for this cluster
30      load_assignment:
31        cluster_name: greeter_service
32        endpoints:
33          - lb_endpoints:
34              - endpoint:
35                  address:
36                    socket_address:
37                      address: 127.0.0.1
38                      port_value: 50051
39admin:
40  access_log_path: "/tmp/admin_access.log"
41  address:
42    socket_address:
43      address: 0.0.0.0
44      port_value: 9900

 1// client.go
 2package main
 3
 4import (
 5    "context"
 6    "log"
 7    "time"
 8
 9    pb "yourmod/helloworld"
10    "google.golang.org/grpc"
11)
12
13func main() {
14    conn, err := grpc.Dial("localhost:9901", grpc.WithInsecure())
15    if err != nil {
16        log.Fatalf("did not connect: %v", err)
17    }
18    defer conn.Close()
19    c := pb.NewGreeterClient(conn)
20
21    ctx, cancel := context.WithTimeout(context.Background(), time.Second)
22    defer cancel()
23    r, err := c.SayHello(ctx, &pb.HelloRequest{Name: "Envoy"})
24    if err != nil {
25        log.Fatalf("could not greet: %v", err)
26    }
27    log.Printf("Greeting: %s", r.Message)
28}

1go run server.go
2envoy -c envoy.yaml
3go run client.go

 1load_assignment:
 2  cluster_name: greeter_service
 3  endpoints:
 4    - lb_endpoints:
 5        - endpoint:
 6            address:
 7              socket_address:
 8                address: 127.0.0.1
 9                port_value: 50051
10        - endpoint:
11            address:
12              socket_address:
13                address: 127.0.0.1
14                port_value: 50052

1health_checks:
2  - timeout: 1s
3    interval: 2s
4    unhealthy_threshold: 2
5    healthy_threshold: 2
6    grpc_health_check: {} # Sesuai standard gRPC health check