golang框架水平扩展与负载均衡

// 使用 Kubernetes 部署 Go 应用
import (
    "context"
    metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    "k8s.io/client-go/kubernetes"
    appsv1 "k8s.io/client-go/kubernetes/typed/apps/v1"
)

func deploy(clientset *kubernetes.Clientset) error {
    deploymentsClient := clientset.AppsV1().Deployments("default")
    deployment := &appsv1.Deployment{
        ObjectMeta: metav1.ObjectMeta{
            Name: "my-deployment",
        },
        Spec: appsv1.DeploymentSpec{
            Selector: &metav1.LabelSelector{
                MatchLabels: map[string]string{
                    "app": "my-app",
                },
            },
            Template: appsv1.PodTemplateSpec{
                ObjectMeta: metav1.ObjectMeta{
                    Labels: map[string]string{
                        "app": "my-app",
                    },
                },
                Spec: corev1.PodSpec{
                    Containers: []corev1.Container{
                        {
                            Name: "my-app",
                            Image: "my-app-image",
                        },
                    },
                },
            },
        },
    }
    _, err := deploymentsClient.Create(context.TODO(), deployment, metav1.CreateOptions{})
    return err
}

// 使用 Traefik 作为负载均衡器
import (
    "context"
    "fmt"

    "github.com/traefik/traefik/v2/pkg/config/dynamic"
)

func setupTraefik(ctx context.Context) error {
    // 读取 Traefik 配置文件
    config, err := dynamic.LoadFile(pathToConfigFile)
    if err != nil {
        return err
    }

    // 创建 Traefik 客户端
    client, err := dynamic.NewClient(config, nil)
    if err != nil {
        return err
    }

    // 添加后端服务器
    backend := dynamic.Backend{
        Servers: []*dynamic.Server{
            {
                URL: "http://localhost:8080",
            },
            {
                URL: "http://localhost:8081",
            },
        },
    }
    if err := client.UpdateBackend(ctx, "my-backend", &backend); err != nil {
        return err
    }

    // 添加前端路由
    frontend := &dynamic.Frontend{
        Backend: "my-backend",
        Routes: []*dynamic.Route{
            {
                Path: "/",
            },
        },
    }
    if err := client.UpdateFrontend(ctx, "my-frontend", frontend); err != nil {
        return err
    }

    fmt.Printf("Traefik 负载均衡器已配置完毕使用后端服务器：%v\n", backend)
    return nil
}

// 使用 Envoy 作为负载均衡器
import (
    "context"

    envoy "github.com/envoyproxy/go-control-plane/envoy/api/v2"
)

func setupEnvoy(ctx context.Context) error {
    // 创建 Envoy 客户端
    client, err := envoy.NewClient(envoy.ConfigSourceGrpc)
    if err != nil {
        return err
    }

    // 添加后端服务器
    backend := &envoy.Cluster{
        Name:         "my-backend",
        Type:         envoy.Cluster_STATIC,
        ConnectTimes: 100,
        LbPolicy:     envoy.Cluster_ROUND_ROBIN,
        LeastRequest: &envoy.Cluster_LeastRequestPolicy{},
        LoadAssignment: &envoy.ClusterLoadAssignment{
            ClusterName: "my-backend",
            Endpoints: []*envoy.Endpoint{
                {Address: &envoy.SocketAddress{Address: "127.0.0.1", PortValue: 8080}},
                {Address: &envoy.SocketAddress{Address: "127.0.0.1", PortValue: 8081}},
            },
        },
    }
    if err := client.CreateCluster(ctx, backend); err != nil {
        return err
    }

    // 添加前端路由
    listener := &envoy.Listener{
        Name:    "my-listener",
        Address: &envoy.Address{Address: &envoy.Address_SocketAddress{SocketAddress: &envoy.SocketAddress{Address: "127.0.0.1", PortValue: 8080}}},
        FilterChains: []*envoy.FilterChain{{
            Filters: []*envoy.Filter{
                {
                    Name:    "envoy.filters.network.http_connection_manager",
                    Config:  &envoy.HttpConnectionManager{RouteConfig: &envoy.HttpConnectionManager_RouteConfig{Name: "inbound"}},
                },
            },
        }},
    }
    if err := client.CreateListener(ctx, listener); err != nil {
        return err
    }

    // 添加路由
    routeConfig := &envoy.RouteConfiguration{
        Name: "inbound",
        VirtualHosts: []*envoy.VirtualHost{{
            Name:    "backend",
            Domains: []string{"my-domain.com"},
            Routes: []*envoy.Route{{
                Match:   &envoy.RouteMatch{PathSpecifier: &envoy.RouteMatch_Prefix{Prefix: "/"}},
                Action:  &envoy.Route_Route{Route: &envoy.RouteAction{Cluster: "my-backend"}},
            },},
        }},
    }
    if err := client.CreateRouteConfiguration(ctx, routeConfig); err != nil {
        return err
    }

    return nil
}