6.【go-kit教程】go-kit服务注册发现与负载均衡
服务注册
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Go-Kit框架本身不提供服务注册中心的实现，但Go-Kit提供了集成第三方服务注册中心的支持
- Consul：Consul是一种开源的服务发现和配置工具。Go-Kit提供了consul包，用于与Consul集成，支持服务注册、服务发现、健康检查等功能。
- etcd：etcd是一个分布式键值存储系统，也可以用于服务注册和服务发现。Go-Kit提供了etcd包，用于与etcd集成，支持服务注册、服务发现、健康检查等功能。
- ZooKeeper：ZooKeeper是一个分布式协调服务，也可以用于服务注册和服务发现。Go-Kit提供了zookeeper包，用于与ZooKeeper集成，支持服务注册、服务发现、健康检查等功能。
- Eureka：Eureka是Netflix开源的服务发现框架，Go-Kit提供了eureka包，用于与Eureka集成，支持服务注册、服务发现、健康检查等功能。
- Nacos：Nacos是阿里巴巴开源的服务发现和配置管理平台，Go-Kit提供了nacos包，用于与Nacos集成，支持服务注册、服务发现、健康检查等功能。
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Go-Kit还提供了sd包，该包提供了一个标准的接口，可以与不同的服务注册中心进行集成。因此，如果你使用的服务注册中心不在上述列表中，你也可以使用sd包进行集成。
1. go-kit集成etcd示例
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register_service 代码
package register_service import ( "context" "fmt" // "github.com/go-kit/kit/sd/etcd" "time" "github.com/go-kit/kit/log" "github.com/go-kit/kit/sd" "github.com/go-kit/kit/sd/etcdv3" "os" ) func RegisterETCD(etcdHost, etcdPort, svcHost, svcPort string, logger log.Logger) (registrar sd.Registrar) { // etcd的地址 etcdServerAddr := []string{fmt.Sprintf("%s:%s", etcdHost, etcdPort)} // 服务的名称和端口 serviceName := "my-service" ttl := 5 * time.Second options := etcdv3.ClientOptions{ DialTimeout: ttl, DialKeepAlive: ttl, } // 创建etcd客户端 etcdClient, err := etcdv3.NewClient(context.Background(), etcdServerAddr, options) if err != nil { fmt.Printf("Failed to create etcd client: %v", err) os.Exit(1) } // 创建一个etcd实例 registrar = etcdv3.NewRegistrar(etcdClient, etcdv3.Service{ Key: serviceName, Value: fmt.Sprintf("%s:%s", svcHost, svcPort), TTL: etcdv3.NewTTLOption(10*time.Second, 5*time.Second), }, logger) return registrar } -
main.go
/** * @date: 2023/2/22 * @desc: */ package main import ( "github.com/go-kit/kit/log/level" "github.com/go-kit/log" "google.golang.org/grpc" "my-kit-register-demo/endpoints" "my-kit-register-demo/middlewares" "my-kit-register-demo/proto" "my-kit-register-demo/register_service" "my-kit-register-demo/services" "my-kit-register-demo/transports" "net" "os" "os/signal" "syscall" ) func main() { logger := log.NewJSONLogger(os.Stdout) listener, err := net.Listen("tcp", "0.0.0.0:8080") if err != nil { level.Error(logger).Log("listen error: ", err.Error()) os.Exit(1) } pingService := services.NewPingService() pingService = middlewares.LoggingPingServiceMiddleware(logger)(pingService) pingEndPoints := endpoints.NewPingEndpoint(pingService) pingGRPCServer := transports.NewPingGRPCServer(pingEndPoints, logger) helloEndPoint := endpoints.NewHelloEndpoint(services.NewHelloService()) helloGRPCServer := transports.NewHelloGRPCServer(helloEndPoint, logger) grpcServer := grpc.NewServer() proto.RegisterHelloServer(grpcServer, helloGRPCServer) proto.RegisterPingServer(grpcServer, pingGRPCServer) // r := register_service.RegisterConsul("172.24.25.123", "8500", "172.24.25.123", "8080", logger) r := register_service.RegisterETCD("172.24.25.123", "2379", "172.24.25.123", "8080", logger) go func() { r.Register() err = grpcServer.Serve(listener) if err != nil { level.Error(logger).Log("grpc error:", err) } }() // 处理终止信号 signalChan := make(chan os.Signal, 1) signal.Notify(signalChan, syscall.SIGTERM, syscall.SIGINT) <-signalChan // 取消注册服务 r.Deregister() }
2. go-kit集成consul示例
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register_service 代码
package register_service import ( "github.com/go-kit/kit/log" "github.com/go-kit/kit/sd" "github.com/go-kit/kit/sd/consul" "github.com/hashicorp/consul/api" "os" "strconv" "time" ) func RegisterConsole(consulHost, consulPort, svcHost, svcPort string, logger log.Logger) (registrar sd.Registrar) { // 创建Consul客户端连接 var client consul.Client { consulCfg := api.DefaultConfig() consulCfg.Address = consulHost + ":" + consulPort consulClient, err := api.NewClient(consulCfg) if err != nil { logger.Log("create consul client error:", err) os.Exit(1) } client = consul.NewClient(consulClient) } // 设置Consul对 http 服务健康检查的参数 // check := api.AgentServiceCheck{ // HTTP: "http://" + svcHost + ":" + svcPort + "/health", // 此接口需要自己实现 // Interval: "10s", // Timeout: "1s", // Notes: "Consul check service health status.", // } // 设置Consul对 GRPC 服务健康检查的参数 check := api.AgentServiceCheck{ GRPC: svcHost + ":" + svcPort , Interval: "5s", Timeout: "1s", Notes: "Consul check service health status.", } port, _ := strconv.Atoi(svcPort) // 设置微服务想Consul的注册信息 reg := api.AgentServiceRegistration{ ID: "my-kit-demo" + time.Now().String(), Name: "my-kit-demo", Address: svcHost, Port: port, Tags: []string{"my-kit", "register-demo"}, // Check: &check, } // 执行注册 registrar = consul.NewRegistrar(client, ®, logger) return } -
man.go
/** * @date: 2023/2/22 * @desc: */ package main import ( "github.com/go-kit/kit/log/level" "github.com/go-kit/log" "google.golang.org/grpc" "google.golang.org/grpc/health" "google.golang.org/grpc/health/grpc_health_v1" "my-kit-register-demo/endpoints" "my-kit-register-demo/middlewares" "my-kit-register-demo/proto" "my-kit-register-demo/register_service" "my-kit-register-demo/services" "my-kit-register-demo/transports" "net" "os" "os/signal" "syscall" ) func main() { defer func() { }() logger := log.NewJSONLogger(os.Stdout) listener, err := net.Listen("tcp", "0.0.0.0:8080") if err != nil { level.Error(logger).Log("listen error: ", err.Error()) os.Exit(1) } pingService := services.NewPingService() pingService = middlewares.LoggingPingServiceMiddleware(logger)(pingService) pingEndPoints := endpoints.NewPingEndpoint(pingService) pingGRPCServer := transports.NewPingGRPCServer(pingEndPoints, logger) helloEndPoint := endpoints.NewHelloEndpoint(services.NewHelloService()) helloGRPCServer := transports.NewHelloGRPCServer(helloEndPoint, logger) grpcServer := grpc.NewServer() // 注册健康检查服务 healthCheckServiceName := "my-grpc-service" healthServer := health.NewServer() healthServer.SetServingStatus(healthCheckServiceName, grpc_health_v1.HealthCheckResponse_SERVING) grpc_health_v1.RegisterHealthServer(grpcServer, healthServer) // 注册健康检查服务 proto.RegisterHelloServer(grpcServer, helloGRPCServer) proto.RegisterPingServer(grpcServer, pingGRPCServer) r := register_service.RegisterConsole("172.24.25.123", "8500", "172.24.25.123", "8080", logger) go func() { r.Register() err = grpcServer.Serve(listener) if err != nil { level.Error(logger).Log("grpc error:", err) } }() // 处理终止信号 signalChan := make(chan os.Signal, 1) signal.Notify(signalChan, syscall.SIGTERM, syscall.SIGINT) <-signalChan // 取消注册服务 r.Deregister() }
服务发现与负载均衡
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go-kit 为不同的服务发现系统（eureka、zookeeper、consul、etcd等）提供适配器，
Endpointer负责监听服务发现系统，并根据需要生成一组相同的endpointtype Endpointer interface { Endpoints() ([]endpoint.Endpoint, error) } -
go-kit 提供了工厂函数——
Factory， 它是一个将实例字符串(例如host:port)转换为特定端点的函数。提供多个端点的实例需要多个工厂函数。工厂函数还返回一个当实例消失并需要清理时调用的io.Closer。type Factory func(instance string) (endpoint.Endpoint, io.Closer, error) -
定义如下工厂函数，它会根据传入的实例地址创建一个 gRPC 客户端的 endpoint。
func factory(instance string) (endpoint.Endpoint, io.Closer, error) { conn, err := grpc.Dial(instance, grpc.WithInsecure()) if err != nil { return nil, nil, err } e := makeEndpoint(conn) return e, conn, err } -
demo：
package register_service import ( "context" "github.com/go-kit/kit/endpoint" "github.com/go-kit/kit/log" "github.com/go-kit/kit/sd" "github.com/go-kit/kit/sd/consul" "github.com/go-kit/kit/sd/lb" "google.golang.org/grpc" "io" "time" ) func MakeConsulDiscoverEndpoint(ctx context.Context, client consul.Client, logger log.Logger) endpoint.Endpoint { serviceName := "my-kit-demo--grpc-check" tags := []string{"my-kit", "register-demo"} duration := 500 * time.Millisecond // 创建consul的连接实例 instance := consul.NewInstancer(client, logger, serviceName, tags, true) // 使用consul连接实例（发现服务系统）、factory创建sd.Factory endpointer := sd.NewEndpointer(instance, factory, logger) // 创建RoundRibbon负载均衡器 balancer := lb.NewRoundRobin(endpointer) // 为负载均衡器增加重试功能，同时该对象为endpoint.Endpoint retry := lb.Retry(1, duration, balancer) return retry } func factory(instance string) (endpoint endpoint.Endpoint, closer io.Closer, err error) { conn, err := grpc.Dial(instance, grpc.WithInsecure()) if err != nil { return nil, nil, err } defer conn.Close() return NewEndpoint(), nil, nil }
完整代码
- https://github.com/daniuEvan/go-kit-demo/tree/main/my-kit-register-demo