nsq源码阅读 nsqlookupd源码五 http.go http_server.go

再来看看关于HTTP的处理逻辑：

httpServer := newHTTPServer(ctx)

新建HTTP实例，跟踪代码，nsqlookupd/http.go：

package nsqlookupdimport ("fmt""net/http""net/http/pprof""sync/atomic""github.com/julienschmidt/httprouter""github.com/nsqio/nsq/internal/http_api""github.com/nsqio/nsq/internal/protocol""github.com/nsqio/nsq/internal/version")type httpServer struct {ctx    *Contextrouter http.Handler}//新建httpServer实例func newHTTPServer(ctx *Context) *httpServer {log := http_api.Log(ctx.nsqlookupd.opts.Logger)router := httprouter.New()router.HandleMethodNotAllowed = truerouter.PanicHandler = http_api.LogPanicHandler(ctx.nsqlookupd.opts.Logger)router.NotFound = http_api.LogNotFoundHandler(ctx.nsqlookupd.opts.Logger)router.MethodNotAllowed = http_api.LogMethodNotAllowedHandler(ctx.nsqlookupd.opts.Logger)s := &httpServer{ctx:    ctx,router: router,}//监听路由router.Handle("GET", "/ping", http_api.Decorate(s.pingHandler, log, http_api.PlainText))router.Handle("GET", "/info", http_api.Decorate(s.doInfo, log, http_api.V1))// v1 negotiaterouter.Handle("GET", "/debug", http_api.Decorate(s.doDebug, log, http_api.V1))router.Handle("GET", "/lookup", http_api.Decorate(s.doLookup, log, http_api.V1))router.Handle("GET", "/topics", http_api.Decorate(s.doTopics, log, http_api.V1))router.Handle("GET", "/channels", http_api.Decorate(s.doChannels, log, http_api.V1))router.Handle("GET", "/nodes", http_api.Decorate(s.doNodes, log, http_api.V1))// only v1router.Handle("POST", "/topic/create", http_api.Decorate(s.doCreateTopic, log, http_api.V1))router.Handle("POST", "/topic/delete", http_api.Decorate(s.doDeleteTopic, log, http_api.V1))router.Handle("POST", "/channel/create", http_api.Decorate(s.doCreateChannel, log, http_api.V1))router.Handle("POST", "/channel/delete", http_api.Decorate(s.doDeleteChannel, log, http_api.V1))router.Handle("POST", "/topic/tombstone", http_api.Decorate(s.doTombstoneTopicProducer, log, http_api.V1))// debugrouter.HandlerFunc("GET", "/debug/pprof", pprof.Index)router.HandlerFunc("GET", "/debug/pprof/cmdline", pprof.Cmdline)router.HandlerFunc("GET", "/debug/pprof/symbol", pprof.Symbol)router.HandlerFunc("POST", "/debug/pprof/symbol", pprof.Symbol)router.HandlerFunc("GET", "/debug/pprof/profile", pprof.Profile)router.Handler("GET", "/debug/pprof/heap", pprof.Handler("heap"))router.Handler("GET", "/debug/pprof/goroutine", pprof.Handler("goroutine"))router.Handler("GET", "/debug/pprof/block", pprof.Handler("block"))router.Handler("GET", "/debug/pprof/threadcreate", pprof.Handler("threadcreate"))return s}func (s *httpServer) ServeHTTP(w http.ResponseWriter, req *http.Request) {s.router.ServeHTTP(w, req)}//GET /pingfunc (s *httpServer) pingHandler(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {return "OK", nil}//GET /infofunc (s *httpServer) doInfo(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {/** *相当于: * type version struct { * Version string `json:"version"` * } * v := &version { *Version: version.Binary, * } * return v, nil */return struct {Version string `json:"version"`}{Version: version.Binary,}, nil}//获取所有topic//GET /topicsfunc (s *httpServer) doTopics(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {//获取所有topic的名称//详情见nsqlookupd/registration_db.go文件中Registrations相关topics := s.ctx.nsqlookupd.DB.FindRegistrations("topic", "*", "").Keys()return map[string]interface{}{"topics": topics,}, nil}//获取指定topic下的所有channel//GET /channels//@param topic - the topic to list channels forfunc (s *httpServer) doChannels(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {reqParams, err := http_api.NewReqParams(req)if err != nil {return nil, http_api.Err{400, "INVALID_REQUEST"}}topicName, err := reqParams.Get("topic")if err != nil {return nil, http_api.Err{400, "MISSING_ARG_TOPIC"}}channels := s.ctx.nsqlookupd.DB.FindRegistrations("channel", topicName, "*").SubKeys()return map[string]interface{}{"channels": channels,}, nil}//获取指定topic下的所有有效producer//GET /lookup//@param topic - the topic to list producers forfunc (s *httpServer) doLookup(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {reqParams, err := http_api.NewReqParams(req)if err != nil {return nil, http_api.Err{400, "INVALID_REQUEST"}}topicName, err := reqParams.Get("topic")if err != nil {return nil, http_api.Err{400, "MISSING_ARG_TOPIC"}}//topic不存在registration := s.ctx.nsqlookupd.DB.FindRegistrations("topic", topicName, "")if len(registration) == 0 {return nil, http_api.Err{404, "TOPIC_NOT_FOUND"}}channels := s.ctx.nsqlookupd.DB.FindRegistrations("channel", topicName, "*").SubKeys()producers := s.ctx.nsqlookupd.DB.FindProducers("topic", topicName, "")//过滤出有效producer//详情可查看nsqlookupd/registration_db.go中Producers的FilterByActive()方法//和nsqlookupd/options.go中的一些默认配置值producers = producers.FilterByActive(s.ctx.nsqlookupd.opts.InactiveProducerTimeout,s.ctx.nsqlookupd.opts.TombstoneLifetime)return map[string]interface{}{"channels":  channels,"producers": producers.PeerInfo(),}, nil}//POST /topic/create//@param topic - the topic to createdfunc (s *httpServer) doCreateTopic(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {reqParams, err := http_api.NewReqParams(req)if err != nil {return nil, http_api.Err{400, "INVALID_REQUEST"}}topicName, err := reqParams.Get("topic")if err != nil {return nil, http_api.Err{400, "MISSING_ARG_TOPIC"}}//验证topic名称是否合法if !protocol.IsValidTopicName(topicName) {return nil, http_api.Err{400, "INVALID_ARG_TOPIC"}}s.ctx.nsqlookupd.logf("DB: adding topic(%s)", topicName)key := Registration{"topic", topicName, ""}s.ctx.nsqlookupd.DB.AddRegistration(key)return nil, nil}//POST /topic/delete//@param topic - the existing topic to deletefunc (s *httpServer) doDeleteTopic(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {reqParams, err := http_api.NewReqParams(req)if err != nil {return nil, http_api.Err{400, "INVALID_REQUEST"}}topicName, err := reqParams.Get("topic")if err != nil {return nil, http_api.Err{400, "MISSING_ARG_TOPIC"}}//先删除topic下的channelregistrations := s.ctx.nsqlookupd.DB.FindRegistrations("channel", topicName, "*")for _, registration := range registrations {s.ctx.nsqlookupd.logf("DB: removing channel(%s) from topic(%s)", registration.SubKey, topicName)s.ctx.nsqlookupd.DB.RemoveRegistration(registration)}//删除topicregistrations = s.ctx.nsqlookupd.DB.FindRegistrations("topic", topicName, "")for _, registration := range registrations {s.ctx.nsqlookupd.logf("DB: removing topic(%s)", topicName)s.ctx.nsqlookupd.DB.RemoveRegistration(registration)}return nil, nil}//POST /topic/tombstone//官方解释Tombstones a specific producer of an existing topic//详情见http://nsq.io/components/nsqlookupd.html#deletion_tombstones//个人理解为逻辑删除指定topic的一个节点(producer)//@param topic - the existing topic//@param node - the producer (nsqd) to tombstone (identified by <broadcast_address>:<http_port>)func (s *httpServer) doTombstoneTopicProducer(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {reqParams, err := http_api.NewReqParams(req)if err != nil {return nil, http_api.Err{400, "INVALID_REQUEST"}}topicName, err := reqParams.Get("topic")if err != nil {return nil, http_api.Err{400, "MISSING_ARG_TOPIC"}}//node格式 <broadcast_address>:<http_port>node, err := reqParams.Get("node")if err != nil {return nil, http_api.Err{400, "MISSING_ARG_NODE"}}s.ctx.nsqlookupd.logf("DB: setting tombstone for producer@%s of topic(%s)", node, topicName)//根据topic查producerproducers := s.ctx.nsqlookupd.DB.FindProducers("topic", topicName, "")for _, p := range producers {thisNode := fmt.Sprintf("%s:%d", p.peerInfo.BroadcastAddress, p.peerInfo.HTTPPort)//逻辑删除if thisNode == node {p.Tombstone()}}return nil, nil}//POST /channel/create//创建topic和channel//@param topic - the topic to created//@param channel - the channel to createdfunc (s *httpServer) doCreateChannel(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {reqParams, err := http_api.NewReqParams(req)if err != nil {return nil, http_api.Err{400, "INVALID_REQUEST"}}//获取topic和channel，并验证是否是有效参数topicName, channelName, err := http_api.GetTopicChannelArgs(reqParams)if err != nil {return nil, http_api.Err{400, err.Error()}}//新增channels.ctx.nsqlookupd.logf("DB: adding channel(%s) in topic(%s)", channelName, topicName)key := Registration{"channel", topicName, channelName}s.ctx.nsqlookupd.DB.AddRegistration(key)//新增topics.ctx.nsqlookupd.logf("DB: adding topic(%s)", topicName)key = Registration{"topic", topicName, ""}s.ctx.nsqlookupd.DB.AddRegistration(key)return nil, nil}//POST /channel/delete//删除已有topic下的一个channel//@param topic - the existing topic//@param channel - the existing channel to deletefunc (s *httpServer) doDeleteChannel(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {reqParams, err := http_api.NewReqParams(req)if err != nil {return nil, http_api.Err{400, "INVALID_REQUEST"}}//获取topic和channel，并验证是否是有效参数topicName, channelName, err := http_api.GetTopicChannelArgs(reqParams)if err != nil {return nil, http_api.Err{400, err.Error()}}//验证channel是否存在指定的topic下registrations := s.ctx.nsqlookupd.DB.FindRegistrations("channel", topicName, channelName)if len(registrations) == 0 {return nil, http_api.Err{404, "CHANNEL_NOT_FOUND"}}s.ctx.nsqlookupd.logf("DB: removing channel(%s) from topic(%s)", channelName, topicName)for _, registration := range registrations {s.ctx.nsqlookupd.DB.RemoveRegistration(registration)}return nil, nil}//定义节点信息(producer (nsqd))type node struct {RemoteAddress    string   `json:"remote_address"`Hostname         string   `json:"hostname"`BroadcastAddress string   `json:"broadcast_address"`TCPPort          int      `json:"tcp_port"`HTTPPort         int      `json:"http_port"`Version          string   `json:"version"`Tombstones       []bool   `json:"tombstones"`Topics           []string `json:"topics"`}//GET /nodes//获取所有已知节点(nsqd)func (s *httpServer) doNodes(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {// don't filter out tombstoned nodesproducers := s.ctx.nsqlookupd.DB.FindProducers("client", "", "").FilterByActive(s.ctx.nsqlookupd.opts.InactiveProducerTimeout, 0)nodes := make([]*node, len(producers))for i, p := range producers {topics := s.ctx.nsqlookupd.DB.LookupRegistrations(p.peerInfo.id).Filter("topic", "*", "").Keys()// for each topic find the producer that matches this peer// to add tombstone informationtombstones := make([]bool, len(topics))for j, t := range topics {topicProducers := s.ctx.nsqlookupd.DB.FindProducers("topic", t, "")for _, tp := range topicProducers {if tp.peerInfo == p.peerInfo {tombstones[j] = tp.IsTombstoned(s.ctx.nsqlookupd.opts.TombstoneLifetime)}}}nodes[i] = &node{RemoteAddress:    p.peerInfo.RemoteAddress,Hostname:         p.peerInfo.Hostname,BroadcastAddress: p.peerInfo.BroadcastAddress,TCPPort:          p.peerInfo.TCPPort,HTTPPort:         p.peerInfo.HTTPPort,Version:          p.peerInfo.Version,Tombstones:       tombstones,Topics:           topics,}}return map[string]interface{}{"producers": nodes,}, nil}//GET /debugfunc (s *httpServer) doDebug(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {s.ctx.nsqlookupd.DB.RLock()defer s.ctx.nsqlookupd.DB.RUnlock()data := make(map[string][]map[string]interface{})for r, producers := range s.ctx.nsqlookupd.DB.registrationMap {key := r.Category + ":" + r.Key + ":" + r.SubKeyfor _, p := range producers {m := map[string]interface{}{"id":                p.peerInfo.id,"hostname":          p.peerInfo.Hostname,"broadcast_address": p.peerInfo.BroadcastAddress,"tcp_port":          p.peerInfo.TCPPort,"http_port":         p.peerInfo.HTTPPort,"version":           p.peerInfo.Version,"last_update":       atomic.LoadInt64(&p.peerInfo.lastUpdate),"tombstoned":        p.tombstoned,"tombstoned_at":     p.tombstonedAt.UnixNano(),}data[key] = append(data[key], m)}}return data, nil}

http.go定义了一系列http handle

继续往下可看到：

http_api.Serve(httpListener, httpServer, "HTTP", l.opts.Logger)

创建HTTP server，代码位于internal/http_api/http_server.go里：

package http_apiimport ("fmt""log""net""net/http""strings""github.com/nsqio/nsq/internal/app")type logWriter struct {app.Logger}func (l logWriter) Write(p []byte) (int, error) {l.Logger.Output(2, string(p))return len(p), nil}//创建HTTP Serve，并注册handler，handler在nsqlookupd/http.go中定义func Serve(listener net.Listener, handler http.Handler, proto string, l app.Logger) {l.Output(2, fmt.Sprintf("%s: listening on %s", proto, listener.Addr()))server := &http.Server{Handler:  handler,ErrorLog: log.New(logWriter{l}, "", 0),}err := server.Serve(listener)// theres no direct way to detect this error because it is not exposedif err != nil && !strings.Contains(err.Error(), "use of closed network connection") {l.Output(2, fmt.Sprintf("ERROR: http.Serve() - %s", err))}l.Output(2, fmt.Sprintf("%s: closing %s", proto, listener.Addr()))}

到这里nsqlookupd模块的代码就看完了，还剩几个小文件就不在这写了。接下来会看nsqd模块的代码。