kratos Consul注册发现使用示例
项目目录
kratos-register -- 为注册项目示例
kratos-discovery -- 为发现项目示例
kratos-discovery\internal\consul -- （核心）为本项目封装的基于Consul服务注册发现的demo
kratos-register\cmd\main.go -- 为服务注册代码示例位置
kratos-discovery\api-register -- 为发现服务调用注册服务的协议文件
kratos-discovery\api\client.go -- 为服务发现示例代码位置
kratos-discovery\internal\dao\dao.go -- 提供service 调用的入口
kratos-discovery\internal\server\service\service.go -- 最终grpc 调用的实际方法
准备前提
- 首先根据官方快速搭建好kratos环境 https://go-kratos.dev/#/quickstart
- 编写好相关服务代码
服务注册
kratos-register\cmd\main.go
func main(){ // 实例化Discovery dis, err := consul.New(&consul.Config{Zone:"zone01", Env:"dev", Region:"region01"}) if err != nil { panic(err) } // 注册为 resolver resolver.Register(dis) ip := "192.168.3.87"//你本地服务的ip地址 到时候可以替换 port := "9002"//你本地grpc 服务的端口 hn, _ := os.Hostname() //dis := discovery.New(nil) ins := &naming.Instance{ Zone: env.Zone, //时区 从环境变量中读取 Env: env.DeployEnv, AppID: "register.service", //服务发现需要用到 Hostname: hn, Addrs: []string{ "grpc://" + ip + ":" + port, }, } cancel, err := dis.Register(context.Background(), ins) if err != nil { panic(err) } signal.Notify(c, syscall.SIGHUP, syscall.SIGQUIT, syscall.SIGTERM, syscall.SIGINT) for { s := <-c log.Info("get a signal %s", s.String()) switch s { case syscall.SIGQUIT, syscall.SIGTERM, syscall.SIGINT: closeFunc() //程序退出时取消consul 注册 windows signal 机制无法命中此方法所以可能在windows环境可能无法模拟取消注册 cancel() log.Info("kratos-register exit") time.Sleep(time.Second) return case syscall.SIGHUP: cancel() default: return } }
服务发现
kratos-discovery\api\client.go
提供NewRegisterClient 方法给dao层使用。
// AppID .这里的AppId 是你需要发现的服务的AppId const AppID = "register.service" func init(){ // NOTE: 注意这段代码，表示要使用服务发现 // NOTE: 还需注意的是，resolver.Register是全局生效的，所以建议该代码放在进程初始化的时候执行 // NOTE: ！！！切记不要在一个进程内进行多个不同中间件的Register！！！ // NOTE: 在启动应用时，可以通过flag(-discovery.nodes) 或者 环境配置(DISCOVERY_NODES)指定discovery节点 resolver.Register(consul.Builder()) } // NewRClient new register grpc client func NewRClient(cfg *warden.ClientConfig, opts ...grpc.DialOption) (register.RegisterClient, error) { client := warden.NewClient(cfg, opts...) //使用consul的 scheme cc, err := client.Dial(context.Background(), fmt.Sprintf("consul://default/%s", AppID)) if err != nil { return nil, err } return register.NewRegisterClient(cc), nil }
kratos-discovery\internal\dao\dao.go
提供注册服务的实例给grpc使用
// Dao dao interface type Dao interface { Close() Ping(ctx context.Context) (err error) // bts: -nullcache=&model.Article{ID:-1} -check_null_code=$!=nil&&$.ID==-1 Article(c context.Context, id int64) (*model.Article, error) //注册的服务接口约束 RegisterLogin(ctx context.Context, req *discoverApi.LoginReq) (reply *discoverApi.LoginResp, err error) } // dao dao. type dao struct { db *sql.DB redis *redis.Redis mc *memcache.Memcache cache *fanout.Fanout demoExpire int32 //暴露给service 接口使用的register.Client client register.RegisterClient } func newDao(r *redis.Redis, mc *memcache.Memcache, db *sql.DB) (d *dao, cf func(), err error) { var cfg struct{ DemoExpire xtime.Duration } if err = paladin.Get("application.toml").UnmarshalTOML(&cfg); err != nil { return } //配置grpc 超时相关配置 grpccfg := &warden.ClientConfig{ Dial: xtime.Duration(time.Second * 10), Timeout: xtime.Duration(time.Second * 1), Subset: 50, KeepAliveInterval: xtime.Duration(time.Second * 60), KeepAliveTimeout: xtime.Duration(time.Second * 20), } var rClient register.RegisterClient //通过服务发现创建registerClient 实例 if rClient,err = discoverApi.NewRClient(grpccfg); err != nil { panic(err) } d = &dao{ db: db, redis: r, mc: mc, cache: fanout.New("cache"), demoExpire: int32(time.Duration(cfg.DemoExpire) / time.Second), //给 client:rClient, } cf = d.Close return } // RegisterLogin 调用服务注册的Login方法 func (d *dao) RegisterLogin(ctx context.Context, req *discoverApi.LoginReq) (reply *discoverApi.LoginResp, err error) { reply2, err := d.client.Login(ctx, (*register.LoginReq)(req)) reply = (*discoverApi.LoginResp)(reply2) return }
kratos-discovery\internal\server\service\service.go
实现协议文件中RegisterLogin 方法
//LoginUrl 登录服务接口逻辑底层调用的是register服务的登录方法 func (s *Service) LoginUrl(ctx context.Context, req *discoverApi.LoginReq) (reply *discoverApi.LoginResp, err error) { fmt.Printf("discovery login username: %s, passwd: %s", req.Username, req.Passwd) //调用dao层的注册方法 reply,err= s.dao.RegisterLogin(ctx,req) return }
kratos-discovery\internal\consul -- （核心）为本项目封装的基于Consul服务注册发现的demo
package discovery import ( "context" "encoding/json" "errors" "fmt" "github.com/go-kratos/kratos/pkg/log" "github.com/go-kratos/kratos/pkg/naming" "github.com/hashicorp/consul/api" "github.com/hashicorp/consul/api/watch" "github.com/hashicorp/go-hclog" "net/url" "strconv" "strings" "sync" "sync/atomic" "time" ) var ( ERR_INS_ADDRS_EMPTY = errors.New("len of ins.Addrs should not be 0") ) type logWrapper struct { } func (wrapper logWrapper) Write(p []byte) (n int, err error) { log.Info(string(p)) return len(p), nil } // Config discovery configures. type Config struct { Nodes []string Region string Zone string Env string Host string } // Resolver resolve naming service type Resolver struct { appID string c chan struct{} client *api.Client agent *api.Agent plan *watch.Plan builder *Discovery ins atomic.Value } func (resolver *Resolver) watch() error { var params map[string]interface{} watchKey := fmt.Sprintf(`{"type":"service", "service":"%s"}`, resolver.appID) if err := json.Unmarshal([]byte(watchKey), ¶ms); err != nil { return err } plan, err := watch.Parse(params) if err != nil { return err } plan.Handler = func(idx uint64, raw interface{}) { if raw == nil { return // ignore } v, ok := raw.([]*api.ServiceEntry) if !ok { return // ignore } log.Info("consul watch service %s notify, len %d", resolver.appID, len(v)) ins := resolver.coverServiceEntry2Ins(v) resolver.ins.Store(ins) resolver.c <- struct{}{} } logger := hclog.NewInterceptLogger(&hclog.LoggerOptions{}) // replace logger go func() { err := plan.RunWithClientAndHclog(resolver.client,logger) if err != nil { log.Error("watch service %s error %s", resolver.appID, err.Error()) } }() resolver.plan = plan return nil } func (resolver *Resolver) Watch() <-chan struct{} { return resolver.c } func (resolver *Resolver) coverServiceEntry2Ins(serviceArr []*api.ServiceEntry) *naming.InstancesInfo { instancesInfo := &naming.InstancesInfo{} //instancesInfo.Scheduler = make([]naming.Zone, 0, 10) instancesInfo.Instances = make(map[string][]*naming.Instance) for _, service := range serviceArr { if service.Checks.AggregatedStatus() == api.HealthPassing { log.Info("appid %s ip %s port %d pass", resolver.appID, service.Service.Address, service.Service.Port) ins := resolver.coverService2Instance(service.Service) if _, ok := instancesInfo.Instances[ins.Zone]; !ok { instancesInfo.Instances[ins.Zone] = make([]*naming.Instance, 0, 10) } instancesInfo.Instances[ins.Zone] = append(instancesInfo.Instances[ins.Zone], ins) } } instancesInfo.LastTs = time.Now().Unix() return instancesInfo } // unused func (resolver *Resolver) fetch(c context.Context) (*naming.InstancesInfo, bool) { _, infoArr, err := resolver.agent.AgentHealthServiceByName(resolver.appID) if err != nil { log.Error("get AgentHealthServiceByName %s err %s", resolver.appID, err.Error()) return nil, false } instancesInfo := &naming.InstancesInfo{} //instancesInfo.Scheduler = make([]naming.Zone, 0, 10) instancesInfo.Instances = make(map[string][]*naming.Instance) log.Info("get AgentHealthServiceByName %s info len %d", resolver.appID, len(infoArr)) for _, info := range infoArr { log.Info("get AgentHealthServiceByName %s info addr %s:%d status: %s", resolver.appID, info.Service.Address, info.Service.Port, info.AggregatedStatus) if info.AggregatedStatus != "passing" { continue } ins := resolver.coverService2Instance(info.Service) if _, ok := instancesInfo.Instances[ins.Zone]; !ok { instancesInfo.Instances[ins.Zone] = make([]*naming.Instance, 0, 10) } instancesInfo.Instances[ins.Zone] = append(instancesInfo.Instances[ins.Zone], ins) } instancesInfo.LastTs = time.Now().Unix() return instancesInfo, true } func (resolver *Resolver) Fetch(c context.Context) (ins *naming.InstancesInfo, ok bool) { v := resolver.ins.Load() ins, ok = v.(*naming.InstancesInfo) return } func (resolver Resolver) Close() error { if resolver.plan != nil && !resolver.plan.IsStopped() { resolver.plan.Stop() } return nil } func (resolver *Resolver) coverService2Instance(service *api.AgentService) *naming.Instance { meta := service.Meta addr := []string{ service.Address + ":" + strconv.Itoa(service.Port), } ins := &naming.Instance{ Region: meta["region"], Zone: meta["zone"], Env: meta["env"], Hostname: meta["hostname"], Version: meta["version"], AppID: service.Service, Addrs: addr, } ins.Metadata = make(map[string]string) for key, value := range meta { if key == "region" || key == "env" || key == "zone" || key == "version" || key == "hostname" { continue } ins.Metadata[key] = value } ins.LastTs = time.Now().Unix() return ins } func (builder Discovery) coverIns2AgentService(ins *naming.Instance) ([]*api.AgentServiceRegistration, error) { if len(ins.Addrs) == 0 { return nil, ERR_INS_ADDRS_EMPTY } registrationArr := make([]*api.AgentServiceRegistration, len(ins.Addrs)) meta := make(map[string]string) meta["region"] = ins.Region meta["zone"] = ins.Zone meta["env"] = ins.Env meta["hostname"] = ins.Hostname meta["version"] = ins.Version meta["last_ts"] = strconv.FormatInt(ins.LastTs, 10) for key, value := range ins.Metadata { meta[key] = value } for i, addr := range ins.Addrs { urlVal, err := url.Parse(addr) if err != nil { return nil, err } port, _ := strconv.Atoi(urlVal.Port()) service := &api.AgentServiceRegistration{ ID: ins.AppID + "-" + urlVal.Hostname() + "-" + urlVal.Port(), Name: ins.AppID, Kind: api.ServiceKindTypical, Port: port, Address: urlVal.Scheme + "://" + urlVal.Hostname(), Meta: meta, } registrationArr[i] = service } return registrationArr, nil } func (builder Discovery) Register(ctx context.Context, ins *naming.Instance) (cancel context.CancelFunc, err error) { serviceArr, err := builder.coverIns2AgentService(ins) if err != nil { return } ctx, cancel = context.WithCancel(ctx) defer func() { if err != nil { // avoid register partition cancel() } }() for _, service := range serviceArr { //@todo 批量注册 service.Check = &api.AgentServiceCheck{ TTL: "15s", Status: api.HealthPassing, } var status string var info *api.AgentServiceChecksInfo status, info, err = builder.agent.AgentHealthServiceByID(service.ID) if err != nil { return } if info == nil && status == api.HealthCritical { err = builder.agent.ServiceRegister(service) // @todo check had registered if err != nil { return } } else { err = builder.agent.PassTTL(fmt.Sprintf("service:%s", service.ID), "I am good :)") if err != nil { return } } go func(service *api.AgentServiceRegistration) { for { select { case <-ctx.Done(): log.Info("ServiceDeregister %s", service.ID) err := builder.agent.ServiceDeregister(service.ID) if err != nil { log.Error("consul: ServiceDeregister %s err: %s", service.ID, err.Error()) } return case <-time.After(time.Second * 5): err := builder.agent.PassTTL(fmt.Sprintf("service:%s", service.ID), "I am good :)") if err == nil { continue } log.Error("consul: PassTTL %s err: %s", service.ID, err.Error()) if strings.Index(err.Error(), "does not have associated TTL") > 0 { // 注册已经失效 err = builder.agent.ServiceRegister(service) // consul 下线会导致 有这个 error if err != nil { log.Error("consul: PassTTL %s reRegister err: %s", service.ID, err.Error()) } } } } }(service) } return } type Discovery struct { client *api.Client agent *api.Agent r map[string]*Resolver locker sync.RWMutex c *Config ctx context.Context cancelFunc context.CancelFunc } func (builder *Discovery) Build(id string, opts ...naming.BuildOpt) naming.Resolver { builder.locker.RLock() if r, ok := builder.r[id]; ok { builder.locker.RUnlock() return r } builder.locker.RUnlock() builder.locker.Lock() r := &Resolver{ appID: id, client: builder.client, agent: builder.agent, builder: builder, } r.c = make(chan struct{}, 10) builder.r[id] = r builder.locker.Unlock() err := r.watch() if err != nil { log.Error("watch error %s", err.Error()) } return r } func (builder *Discovery) Scheme() string { return "consul" } var ( _once sync.Once _builder naming.Builder ) func Builder() naming.Builder { _once.Do(func() { _builder,_ = New(nil) }) return _builder } func New(c *Config) (builder *Discovery, err error) { if c == nil { c = new(Config) } client, err := api.NewClient(api.DefaultConfig()) ctx, cancel := context.WithCancel(context.Background()) if err != nil { return } builder= &Discovery{ client: client, agent: client.Agent(), ctx: ctx, cancelFunc: cancel, c: c, r: make(map[string]*Resolver), } return }
设置环境变量（以goland示例）
consul 环境变量参考
// HTTPAddrEnvName defines an environment variable name which sets // the HTTP address if there is no -http-addr specified. HTTPAddrEnvName = "CONSUL_HTTP_ADDR" // HTTPTokenEnvName defines an environment variable name which sets // the HTTP token. HTTPTokenEnvName = "CONSUL_HTTP_TOKEN" // HTTPTokenFileEnvName defines an environment variable name which sets // the HTTP token file. HTTPTokenFileEnvName = "CONSUL_HTTP_TOKEN_FILE" // HTTPAuthEnvName defines an environment variable name which sets // the HTTP authentication header. HTTPAuthEnvName = "CONSUL_HTTP_AUTH" // HTTPSSLEnvName defines an environment variable name which sets // whether or not to use HTTPS. HTTPSSLEnvName = "CONSUL_HTTP_SSL" // HTTPCAFile defines an environment variable name which sets the // CA file to use for talking to Consul over TLS. HTTPCAFile = "CONSUL_CACERT" // HTTPCAPath defines an environment variable name which sets the // path to a directory of CA certs to use for talking to Consul over TLS. HTTPCAPath = "CONSUL_CAPATH" // HTTPClientCert defines an environment variable name which sets the // client cert file to use for talking to Consul over TLS. HTTPClientCert = "CONSUL_CLIENT_CERT" // HTTPClientKey defines an environment variable name which sets the // client key file to use for talking to Consul over TLS. HTTPClientKey = "CONSUL_CLIENT_KEY" // HTTPTLSServerName defines an environment variable name which sets the // server name to use as the SNI host when connecting via TLS HTTPTLSServerName = "CONSUL_TLS_SERVER_NAME" // HTTPSSLVerifyEnvName defines an environment variable name which sets // whether or not to disable certificate checking. HTTPSSLVerifyEnvName = "CONSUL_HTTP_SSL_VERIFY" // GRPCAddrEnvName defines an environment variable name which sets the gRPC // address for consul connect envoy. Note this isn't actually used by the api // client in this package but is defined here for consistency with all the // other ENV names we use. GRPCAddrEnvName = "CONSUL_GRPC_ADDR"
stay hungry stay foolish！
