gRPC服务反射协议

27 Aug 2022

2 minutes reading time

本文主要介绍 gRPC 的服务反射协议和相关的应用。

#介绍

gRPC 服务反射协议 (server reflection) 是在 gRPC 服务端定义的一个服务,它能提供该服务器端上可公开使用的 gRPC 服务的信息,简单的来说,就是服务反射向客户端提供了服务端注册的服务的信息。 因此客户端不需要预编译服务定义就能与服务端交互了。

客户端想要与服务端程序进行通信,必须要有所定义的服务信息,需要编译生产客户端存根,借助 gRPC 服务反射协议,我们就可以无需编译服务定义就能通信。

#使用

该如何开启服务反射协议呢? 很简单,只需要通过一行代码即可开启: reflection.Register()

package main

import (
	"context"
	"flag"
	"fmt"
	"log"
	"net"

	"google.golang.org/grpc"
	"google.golang.org/grpc/reflection"

	ecpb "google.golang.org/grpc/examples/features/proto/echo"
	hwpb "google.golang.org/grpc/examples/helloworld/helloworld"
)

var port = flag.Int("port", 50051, "the port to serve on")

// hwServer is used to implement helloworld.GreeterServer.
type hwServer struct {
	hwpb.UnimplementedGreeterServer
}

// SayHello implements helloworld.GreeterServer
func (s *hwServer) SayHello(ctx context.Context, in *hwpb.HelloRequest) (*hwpb.HelloReply, error) {
	return &hwpb.HelloReply{Message: "Hello " + in.Name}, nil
}

type ecServer struct {
	ecpb.UnimplementedEchoServer
}

func (s *ecServer) UnaryEcho(ctx context.Context, req *ecpb.EchoRequest) (*ecpb.EchoResponse, error) {
	return &ecpb.EchoResponse{Message: req.Message}, nil
}

func main() {
	flag.Parse()
	lis, err := net.Listen("tcp", fmt.Sprintf(":%d", *port))
	if err != nil {
		log.Fatalf("failed to listen: %v", err)
	}
	fmt.Printf("server listening at %v\n", lis.Addr())

	s := grpc.NewServer()

	// Register Greeter on the server.
	hwpb.RegisterGreeterServer(s, &hwServer{})

	// Register RouteGuide on the same server.
	ecpb.RegisterEchoServer(s, &ecServer{})

	// Register reflection service on gRPC server.
	reflection.Register(s)

	if err := s.Serve(lis); err != nil {
		log.Fatalf("failed to serve: %v", err)
	}
}

服务端开启服务反射协议后,就可以通过 gRPC CLI 工具来检查服务端了。这里就不多介绍了,接下来我们来看看服务反射协议在 kratos 中的使用。

#kratos 中的应用

在一次调试 gRPC 接口中,当时我是使用 postman 调试的,发现我输入了 gRPC 服务的地址,就会显示出我定义的所有服务。看了提示,kratos 应该也使用了服务反射协议。

接下来我们通过 kratos 源码来看看,

func NewServer(opts ...ServerOption) *Server {
	srv := &Server{
		baseCtx: context.Background(),
		network: "tcp",
		address: ":0",
		timeout: 1 * time.Second,
		health:  health.NewServer(),
		log:     log.NewHelper(log.GetLogger()),
	}
	for _, o := range opts {
		o(srv)
	}
	unaryInts := []grpc.UnaryServerInterceptor{
		srv.unaryServerInterceptor(),
	}
	streamInts := []grpc.StreamServerInterceptor{
		srv.streamServerInterceptor(),
	}
	if len(srv.unaryInts) > 0 {
		unaryInts = append(unaryInts, srv.unaryInts...)
	}
	if len(srv.streamInts) > 0 {
		streamInts = append(streamInts, srv.streamInts...)
	}
	grpcOpts := []grpc.ServerOption{
		grpc.ChainUnaryInterceptor(unaryInts...),
		grpc.ChainStreamInterceptor(streamInts...),
	}
	if srv.tlsConf != nil {
		grpcOpts = append(grpcOpts, grpc.Creds(credentials.NewTLS(srv.tlsConf)))
	}
	if len(srv.grpcOpts) > 0 {
		grpcOpts = append(grpcOpts, srv.grpcOpts...)
	}
	srv.Server = grpc.NewServer(grpcOpts...)
	srv.metadata = apimd.NewServer(srv.Server)
	// listen and endpoint
	srv.err = srv.listenAndEndpoint()
	// internal register
	grpc_health_v1.RegisterHealthServer(srv.Server, srv.health)
	apimd.RegisterMetadataServer(srv.Server, srv.metadata)
	reflection.Register(srv.Server)
	return srv
}

可以看到 kratos 也注册了我们定义的所有服务和内置的健康检查服务。

#参考



/sw-load.js?v=e5ae5a1ed170f4499ac6292e7164b68528c51f6d6518cd75a49e6a6b737831d5728da21fc14dcbc7a91328e53858c6ff7195cc3fc8b25f0feeaef2af151d6686 /fireball.gif?v=569e393374f2af74d6c575090904aaf51e641e5eb5ea89ae7c7de01f7293abc165b3a7e8685690a8b951c778603fec98ae6822ff2f7ea86a536776966cb65d5d /favicon.ico?v=beac62000b1965d4e036575d58ef681f6d4c35c6b7ccafb1e286f99bebd3ca5f30f51dd9dcfb4b832132891ff814b18f1e040c08fc7a49be064016fab53c26b3 /favicon-16x16.png?v=5a9fcce4aea1dfb145b39a296c90c3fd0cac49dd7a83999a2bdd2a0ee4e6950f3a1b1f1fe14522b2fcb4cad75734f2a4e84fd964b56217748b9778a2e1697ff7 /favicon-32x32.png?v=35be3e52467cebe716e17b163f587373cd6c52d1993e868caae46dbfc53ba6955ca6ea2c77119ab6d8e535f2cdde502bcf7fe60984f83d2cdb36ee6b92ee37cb /icon-192x192.png?v=3820c1b1e6d755d2b7c2a04a65f0f1feef793b297f7ee995947137ccd8f73ec304457f6ce1df987a9a0a13ed7dacd203225505b832ccd2318b530ae53a55cebc /icon-512x512.png?v=de62ae905479fd813300d286ed1d2fe6bb6f6292623a5d918691642f6dd09a68943c69ed2a95a1820076919e69ff4fda668bb79e610ebc1d3200fedd7f634443 /apple-touch-icon.png?v=5d32464a608cc4b6e656e7be5bba48360b472b399ab82ebf4bbf4a93bb964e26f7bb0a1897ebbbdaf11444e7a93215f04f1c7fe8c08df5dddeeddbf97f93e149 /main.css?v=8ab3ba2ea49a89d1cee56b62a947c88597785d0842586199965b60438f9430279525aef9d01320077a32656df3e7435d48ccd7228cfc9bcd6a97ff0a4cc79358 /nerd-fonts.css?v=4213ecfcacca379b433c0fd135281c627c074e42d243cca41777df5738649704db63d448a19b13f80dfc9337485d8a1eb1a4b77cf2fa9d1fe2d3b6768c66e7bb /unstyle.css?v=b14bd48a2efbd463d973763aa3184c69aa02164c0891acacc9eab49ddd275f98f0050b4c31d2093e4671e7abe04f9459a041f0064384a90d97b8ff21b6824825 /langs.css?v=12474958ee314a9fde4704e1f5a032dc632d41f9461faca326ac284297766c4ceb07b45fec7fbc09fa72b0f21dcc64f0c31e64fc2e5e838b1d30f5fe540afd78 /syntax-theme-light.css?v=ccdddc2d2d88953c6d7d0376777b8409028ef625a7321dfa41619547b4f5eddbe89aa95ff5e7e2620da0ea13fbabebe2fd544620bc7e81e3294776b3425df48a /syntax-theme-dark.css?v=dfede4879841e4a58e5fc71115aa5f5b82e206d85eb771ff4e5a40a1d82621570aad2458f637365ae4370d9a1cf5070edc9765f7c2d4506e12e2ba3c6081ffd5 /sw-style.css?v=352cab856807e725351d62a9cae9dc445a675ab7e0bb0d3b12440b08dd574526c62827a5f4af706f7ad74df996a7f71f2c2a306fc1b188e1560007f0d4eda4fc /posts/page/2/ /posts/page/3/ /posts/page/4/ /posts/page/5/ /posts/page/6/ /posts/page/7/ /posts/page/8/ /posts/page/9/ /posts/page/10/ /posts/page/11/ /posts/page/12/ /posts/page/13/ /posts/page/14/ /posts/page/15/ /posts/page/16/ /categories/ /tags/ /tags/413/ /tags/a-li-yun/ /tags/a-li-yun-oss/ /tags/acme-sh/ /tags/adsense/ /tags/aes/ /tags/ai/ /tags/aliyun/ /tags/an-quan/ /tags/apisix/ /tags/archive-zip/ /tags/atop/ /tags/authing/ /tags/bei-fen/ /tags/ben-di-hua/ /tags/bian-ma/ /tags/bing-fa-bian-cheng/ /tags/bot/ /tags/buf/ /tags/casbin/ /tags/cdn/ /tags/ce-lue-mo-shi/ /tags/cert-manager/ /tags/certificatemanager/ /tags/chrome/ /tags/ci/ /tags/clarity/ /tags/clean-cache/ /tags/cody/ /tags/colab/ /tags/conc/ /tags/concurrency/ /tags/configmaps/ /tags/consul/ /tags/containerd/ /tags/coverage/ /tags/coze/ /tags/cpu/ /tags/crash/ /tags/crawler/ /tags/crypto/ /tags/cte/ /tags/cuo-wu-chu-li/ /tags/cve-2021-22205/ /tags/data-visualization/ /tags/database/ /tags/datax/ /tags/date/ /tags/decode/ /tags/dms/ /tags/dns/ /tags/dns-authorization/ /tags/docker/ /tags/duo-lu-fu-yong/ /tags/duo-ping-tai-bo-ke-fa-bu-gong-ju/ /tags/easeprobe/ /tags/email/ /tags/embed/ /tags/ent/ /tags/errgroup/ /tags/error/ /tags/external/ /tags/fang-wen-kong-zhi/ /tags/fen-bu-shi-lian-lu-zhui-zong/ /tags/ffmpeg/ /tags/finalizers/ /tags/fly-io/ /tags/fsck/ /tags/fu-wu-fan-she-xie-yi/ /tags/fu-zai-jun-heng/ /tags/gcloud/ /tags/gin/ /tags/github/ /tags/github-pages/ /tags/gitlab/ /tags/go/ /tags/golang/ /tags/gonew/ /tags/gong-ju/ /tags/google/ /tags/google-analytics/ /tags/google-api/ /tags/google-cloud/ /tags/google-oauth2/ /tags/govulncheck/ /tags/grafana/ /tags/grpc/ /tags/gzip/ /tags/health-check/ /tags/helm/ /tags/hosts/ /tags/http/ /tags/https/ /tags/hugo/ /tags/humanize/ /tags/i18n/ /tags/image-compress/ /tags/imap/ /tags/init/ /tags/jian-kang-jian-cha/ /tags/jian-kang-tan-zhen/ /tags/jian-kong/ /tags/json/ /tags/k8s/ /tags/katana/ /tags/ke-shi-hua/ /tags/kratos/ /tags/kubernetes/ /tags/lan-jie-qi/ /tags/lint/ /tags/linter/ /tags/linux/ /tags/liu-lan-qi/ /tags/load-balancing/ /tags/log/ /tags/loki/ /tags/lua/ /tags/magika/ /tags/mapping/ /tags/markdown/ /tags/memory/ /tags/mergo/ /tags/metabase/ /tags/microsoft/ /tags/minio/ /tags/mo-hu-ce-shi/ /tags/monitor/ /tags/nei-cun/ /tags/nginx/ /tags/nginx-ingress/ /tags/node-js/ /tags/novelai/ /tags/oauth2/ /tags/once/ /tags/opentelemetry/ /tags/opentracing/ /tags/openwrite/ /tags/os/ /tags/paas/ /tags/performance/ /tags/playwright/ /tags/playwright-go/ /tags/plugin/ /tags/png/ /tags/pngcrush/ /tags/pngquant/ /tags/postgresql/ /tags/profiling/ /tags/prometheus/ /tags/protobuf/ /tags/proxy/ /tags/psutil/ /tags/pyroscope/ /tags/rancher/ /tags/rand/ /tags/redis/ /tags/ren-gong-zhi-neng/ /tags/ren-zheng/ /tags/retry/ /tags/reverse-proxy/ /tags/rong-qi/ /tags/rueidis/ /tags/sealos/ /tags/security/ /tags/server-reflection/ /tags/serverless/ /tags/service/ /tags/she-ji-mo-shi/ /tags/shi-jian-chu-li/ /tags/shu-ju-fen-xi/ /tags/singleflight/ /tags/slug/ /tags/soap/ /tags/spider/ /tags/sql/ /tags/sqlc/ /tags/stable-diffusion/ /tags/storage/ /tags/superset/ /tags/swap/ /tags/sync/ /tags/tcp-udp/ /tags/template/ /tags/test/ /tags/text/ /tags/tianji/ /tags/time/ /tags/tls/ /tags/tong-xin-mo-shi/ /tags/trace/ /tags/trace-viewer/ /tags/traefik/ /tags/tu-pian/ /tags/ubuntu/ /tags/uri/ /tags/v0-dev/ /tags/video/ /tags/visualization/ /tags/visualstudio/ /tags/wang-luo/ /tags/wang-ye-tan-ce/ /tags/wasi/ /tags/wasm/ /tags/wire/ /tags/wireshark/ /tags/wsdl/ /tags/wsl/ /tags/xiao-wen-ti/ /tags/xie-cheng/ /tags/xun-huan/ /tags/you-jian/ /tags/yu-ming/ /tags/yuan-shu-ju/ /tags/zheng-shu/ /tags/zhong-jian-jian/ /tags/zhua-bao/ /tags/zhuang-tai-ma/ /posts/go-recivie-email/ /posts/go-soap-desc/ /posts/docker-desktop-proxy/ /posts/hugo-deploy-github/ /posts/v0dev/ /posts/markdown-preview-enhanced/ /posts/go-humanize-introduce/ /posts/wsl-error1/ /posts/cody/ /posts/katana/ /posts/tianji/ /posts/magika/ /posts/cozebot/ /posts/go-generate-slug/ /posts/metabase/ /posts/gogenerategaid/ /posts/docker-init-command/ /posts/grpc-client-load-balancing/ /posts/grpcqing-qiu-zhong-shi/ /posts/alliyunrdserr/ /posts/kubernetes-resource-reservation/ /posts/atop/ /posts/kubernetes-externalname/ /posts/go-refresh-cdn/ /posts/apisix-enabled-gzip/ /posts/ru-he-shou-ji-xi-tong-dang-ji-hou-de-nei-cun-zhuan-chu-xin-xi/ /posts/conversion-of-chinese-characters-into-pinyin/ /posts/mergo-desc/ /posts/conc-better-structured-concurrency-for-go/ /posts/kubernetes-externaltrafficpolicy/ /posts/clarity-learn/ /posts/postgresql-cte-expressions/ /posts/go-design-patterns-strategy/ /posts/go1-22-new-for-loop/ /posts/apisix-proxy-grpc-service/ /posts/golou-dong-guan-li-gong-ju-govulncheck/ /posts/go-wdsl/ /posts/nginx-ingress-httpqing-qiu-413wen-ti-ji-jie-jue-fang-fa/ /posts/playwright-gojian-jie/ /posts/google-api-go-clientdiao-yong-googleadsensebao-gao-jie-kou-shi-bai-de-wen-ti-ji-jie-jue-fang-an/ /posts/gonewjian-jie/ /posts/ent-sql-modifier/ /posts/golang-embedjian-dan-jie-shao/ /posts/nginxfan-xiang-dai-li-cuo-wu-de-wen-ti-ji-jie-jue-fang-fa/ /posts/shi-yong-cert-managershen-qing-mian-fei-zheng-shu/ /posts/go-i18n/ /posts/rueidisjian-jie/ /posts/postgresqlzen-me-jie-jue-division-by-zerowen-ti/ /posts/kubernetes-healthcheck/ /posts/ranchercattleclusteragentcouldnotresolvehost/ /posts/sealos-version-compare-error/ /posts/kubernetes-podxiu-gai-hostswen-jian/ /posts/apisixhu-lue-urida-xiao-xie/ /posts/sqlcchu-ti-yan/ /posts/apisix-dockerbu-shu-zhong-ding-xiang-wen-ti/ /posts/go-wasi/ /posts/goshi-xian-jian-dan-fan-xiang-dai-li/ /posts/certificatemanagershi-yong-dnsshou-quan-shen-qing-zheng-shu/ /posts/googlecloudqing-chu-cdnhuan-cun/ /posts/apisixshu-ju-bei-fen/ /posts/apisixru-he-tian-jia-zi-ding-yi-cha-jian/ /posts/apisixgen-ju-qing-qiu-hostfang-wen-bu-tong-lu-jing/ /posts/shi-yong-acmezi-dong-geng-xin-apisix-sslzheng-shu/ /posts/containerdben-di-diao-shi-huan-jing-da-jian/ /posts/containerdjian-dan-an-zhuang-he-ke-hu-duan-shi-yong/ /posts/helmjie-shao-ji-shi-yong/ /posts/ubuntu20-04she-zhi-dns/ /posts/postgresqlde-jsonlei-xing/ /posts/shi-yong-apisixdai-li-postgresqlfu-wu/ /posts/dataxshu-ju-tong-bu-zhong-yu-dao-de-wen-ti/ /posts/goshi-jian-chu-li-ku-carbon/ /posts/supersetjian-dan-shi-yong/ /posts/shi-yong-fly-iobu-shu-miniodui-xiang-cun-chu-fu-wu/ /posts/fly-iobu-shu-goying-yong/ /posts/pngya-suo-gong-ju/ /posts/apisixshi-xian-nginxde-proxy-hide-headercan-shu/ /posts/qian-hou-duan-shi-yong-aesjia-mi-chuan-shu-shu-ju/ /posts/fly-iochu-ti-yan/ /posts/aihui-hua-chu-ti-yan/ /posts/kubernetes-configmaps-subpath-no-reload/ /posts/easeprobejian-dan-jie-shao-shi-yong/ /posts/grpczhong-jian-jian/ /posts/gitlab-cve-2021-22205/ /posts/grpcqing-qiu-zhua-bao/ /posts/grpc-server-reflection/ /posts/prometheus-operato/ /posts/gojin-xing-liu-lan-qi-wang-ye-jie-tu/ /posts/gopsutiljie-shao/ /posts/ji-yi-ci-a-li-yun-ossbao-cuo-de-jie-jue/ /posts/grpcjian-kang-tan-zhen/ /posts/grpcjian-kang-jian-cha/ /posts/gofa-song-you-jian/ /posts/goxie-cheng-bi-bao-de-wen-ti/ /posts/goya-suo-pngtu-xiang-da-xiao/ /posts/gochu-li-zipjie-ya-luan-ma-wen-ti/ /posts/singleflightjie-shao/ /posts/goding-shi-jian-kong-httpszheng-shu/ /posts/gobing-fa-sync-oncejie-xi/ /posts/gojie-qu-shi-pin-mou-yi-zheng-tu-pian/ /posts/go-errgroup/ /posts/ying-yong-nei-cun-sheng-gao-yuan-yin-pai-cha/ /posts/duo-ping-tai-bo-ke-fa-bu-gong-ju-openwriteshi-yong/ /posts/bufchu-ru-men-2/ /posts/bufchu-ru-men-1/ /posts/gotong-ji-dai-ma-ce-shi-fu-gai-lu/ /posts/kswapd0-consumes-a-lot-of-cpu/ /posts/kswapd0xiao-hao-da-liang-cpu/ /posts/postgresqlxiu-gai-xu-lie-chan-sheng-qi-de-can-shu/ /posts/kratosye-wu-zhuang-tai-ma-he-httpzhuang-tai-ma-fen-chi/ /posts/apisixshi-yong-authingjin-xing-ren-zheng-deng-lu/ /posts/google-oauth2shi-jian/ /posts/gomo-hu-ce-shi/ /posts/pyroscope-chi-xu-fen-ping-tai/ /posts/fsck/ /posts/grpcdan-xiang-an-quan-lian-jie/ /posts/log-and-trace/ /posts/k8s-finalizers/ /posts/casbinxue-xi-1/ /posts/goru-he-shi-yong-si-you-cang-ku-mo-kuai/ /posts/grpcduo-lu-fu-yong/ /posts/trace-in-sql/ /posts/grpcyuan-shu-ju/ /posts/golangduo-ban-ben-gong-cun/ /posts/grpccuo-wu-chu-li/ /posts/grpclan-jie-qi/ /posts/grpctong-xin-mo-shi/ /posts/gochang-jian-linter/ /posts/wasmingo/ /posts/containerdpei-zhi-si-you-cang-ku/ /posts/rong-qi-chu-xian-shi-jian-yi-chang-wen-ti-ji-jie-jue-fang-fa/ /posts/consulxue-xi/ /posts/kubernetesan-zhuang-apisix/ /posts/she-zhi-rancherfu-wu-qi-de-ben-di-kubernetesji-qun/ /posts/shi-yong-sealosbu-shu-kubernetesji-qun/ /posts/kratoszi-ding-yi-handlerfunc-mei-you-qing-qiu-ri-zhi-de-wen-ti-ji-jie-jue/ /posts/rsstest/ /posts/golangsui-ji-timesleepchu-xian-de-wen-ti/ /posts/ru-he-zai-ginzhong-cha-kan-prometheuszhi-biao/ /posts/shi-yong-prometheusshou-ji-miniozhi-biao/ /posts/fen-bu-shi-lian-lu-zhui-zong-chu-tan-2/ /posts/fen-bu-shi-lian-lu-zhui-zong-chu-tan/ /posts/bian-li-maplie-biao-de-golangmo-ban/ /posts/golang-templates/ /posts/wireru-men/ /posts/gofan-xing-chu-tan/ /posts/functional-options/ /posts/docker-grafanaqi-dong-shi-bai/ /posts/nginxda-jian-jing-tai-tu-pian-zi-yuan-fu-wu-qi/ /posts/traefikru-men-shi-yong/ /posts/go-modulezhi-nan-he-chang-jian-wen-ti/ /posts/gitlab-cigou-jian-dockerjing-xiang/ /posts/github-pagezi-ding-yi-yu-ming/ /posts/gocuo-wu-shi-jian/ /posts/shi-yong-redisshi-xian-dui-lie/ /posts/my-first-post/ /atom.xml /posts/ c1tyh4ll.png?v=e6bb8cdead47e48c0deba1e0a3016070984b5f7271166a72638f9ec5a6ef2d2eb8012e8e4cb64f4f3b6574c6d708bf2ae660d04b8b59a6de675ce4d4d62dd4c3 bk-prk.png?v=b00246fb5faeab35a588f347224b00d53083a9d5f4ae8cd87c0c2e0432bf7f348c6a6ab6f4e4edaf5ddbf13ee34b24946dd0af4cd7db6f4f334599f38917ac9e bk-prk.png?v=b00246fb5faeab35a588f347224b00d53083a9d5f4ae8cd87c0c2e0432bf7f348c6a6ab6f4e4edaf5ddbf13ee34b24946dd0af4cd7db6f4f334599f38917ac9e /icon-192x192.png?v=3820c1b1e6d755d2b7c2a04a65f0f1feef793b297f7ee995947137ccd8f73ec304457f6ce1df987a9a0a13ed7dacd203225505b832ccd2318b530ae53a55cebc /sitemap.xml /search_index.en.json /search.js /elasticlunr.min.js?v=d106ab529e29f6be48a948124723fcf411e06b8e4ea4477b551f256d190991fe3ca7f121714ef8d9f594a4aa680f2bbd37a5d8004abfbf3ea6eb3d4ea259ec0f">