Change:
ServeLogs(w http.ResponseWriter, req *http.Request) } <ins> // NewServer initializes and configures a kubelet.Server object to handle HTTP requests func NewServer(host HostInterface, updates chan<- interface{}) Server { server := Server{ host:    host, updates: updates, mux:     http.NewServeMux(), } server.InstallDefaultHandlers() return server } // InstallDefaultHandlers registers the set of supported HTTP request patterns with the mux func (s *Server) InstallDefaultHandlers() { s.mux.HandleFunc("/healthz", s.handleHealth) s.mux.HandleFunc("/container", s.handleContainer) s.mux.HandleFunc("/containers", s.handleContainers) s.mux.HandleFunc("/podInfo", s.handlePodInfo) s.mux.HandleFunc("/stats/", s.handleStats) s.mux.HandleFunc("/logs/", s.handleLogs) s.mux.HandleFunc("/spec/", s.handleSpec) } // error serializes an error object into an HTTP response </ins> func (s *Server) error(w http.ResponseWriter, err error) { http.Error(w, fmt.Sprintf("Internal Error: %v", err), http.StatusInternalServerError) } <del> func (s *Server) ServeHTTP(w http.ResponseWriter, req *http.Request) { defer httplog.MakeLogged(req, &w).StacktraceWhen( httplog.StatusIsNot( http.StatusOK, http.StatusNotFound, ), ).Log() </del> <ins> // handleHealth handles health checking requests against the Kubelet func (s *Server) handleHealth(w http.ResponseWriter, req *http.Request) { } // handleContainer handles container requests against the Kubelet func (s *Server) handleContainer(w http.ResponseWriter, req *http.Request) { defer req.Body.Close() data, err := ioutil.ReadAll(req.Body) if err != nil { s.error(w, err) return } // This is to provide backward compatibility. It only supports a single manifest var pod Pod err = yaml.Unmarshal(data, &pod.Manifest) if err != nil { s.error(w, err) return } //TODO: sha1 of manifest? pod.Name = "1" s.updates <- PodUpdate{[]Pod{pod}, SET} } // handleContainers handles containers requests against the Kubelet func (s *Server) handleContainers(w http.ResponseWriter, req *http.Request) { defer req.Body.Close() data, err := ioutil.ReadAll(req.Body) if err != nil { s.error(w, err) return } var manifests []api.ContainerManifest err = yaml.Unmarshal(data, &manifests) if err != nil { s.error(w, err) return } pods := make([]Pod, len(manifests)) for i := range manifests { pods[i].Name = fmt.Sprintf("%d", i+1) pods[i].Manifest = manifests[i] } s.updates <- PodUpdate{pods, SET} } // handlePodInfo handles podInfo requests against the Kubelet func (s *Server) handlePodInfo(w http.ResponseWriter, req *http.Request) { </ins> u, err := url.ParseRequestURI(req.RequestURI) if err != nil { s.error(w, err) return } <del> // TODO: use an http.ServeMux instead of a switch. switch { case u.Path == "/container" || u.Path == "/containers": defer req.Body.Close() data, err := ioutil.ReadAll(req.Body) if err != nil { s.error(w, err) return } if u.Path == "/container" { // This is to provide backward compatibility. It only supports a single manifest var pod Pod err = yaml.Unmarshal(data, &pod.Manifest) if err != nil { s.error(w, err) return } //TODO: sha1 of manifest? pod.Name = "1" s.updates <- PodUpdate{[]Pod{pod}, SET} } else if u.Path == "/containers" { var manifests []api.ContainerManifest err = yaml.Unmarshal(data, &manifests) if err != nil { s.error(w, err) return } pods := make([]Pod, len(manifests)) for i := range manifests { pods[i].Name = fmt.Sprintf("%d", i+1) pods[i].Manifest = manifests[i] } s.updates <- PodUpdate{pods, SET} } case u.Path == "/podInfo": podID := u.Query().Get("podID") if len(podID) == 0 { w.WriteHeader(http.StatusBadRequest) http.Error(w, "Missing 'podID=' query entry.", http.StatusBadRequest) return } // TODO: backwards compatibility with existing API, needs API change podFullName := GetPodFullName(&Pod{Name: podID, Namespace: "etcd"}) info, err := s.host.GetPodInfo(podFullName) if err == ErrNoContainersInPod { http.Error(w, "Pod does not exist", http.StatusNotFound) return } if err != nil { s.error(w, err) return } data, err := json.Marshal(info) if err != nil { s.error(w, err) return } w.WriteHeader(http.StatusOK) w.Header().Add("Content-type", "application/json") w.Write(data) case strings.HasPrefix(u.Path, "/stats"): s.serveStats(w, req) case strings.HasPrefix(u.Path, "/spec"): info, err := s.host.GetMachineInfo() if err != nil { s.error(w, err) return } data, err := json.Marshal(info) if err != nil { s.error(w, err) return } w.Header().Add("Content-type", "application/json") w.Write(data) case strings.HasPrefix(u.Path, "/logs/"): s.host.ServeLogs(w, req) default: if s.handler != nil { s.handler.ServeHTTP(w, req) } </del> <ins> podID := u.Query().Get("podID") if len(podID) == 0 { w.WriteHeader(http.StatusBadRequest) http.Error(w, "Missing 'podID=' query entry.", http.StatusBadRequest) return } // TODO: backwards compatibility with existing API, needs API change podFullName := GetPodFullName(&Pod{Name: podID, Namespace: "etcd"}) info, err := s.host.GetPodInfo(podFullName) if err == ErrNoContainersInPod { http.Error(w, "Pod does not exist", http.StatusNotFound) return </ins> } <ins> if err != nil { s.error(w, err) return } data, err := json.Marshal(info) if err != nil { s.error(w, err) return } w.WriteHeader(http.StatusOK) w.Header().Add("Content-type", "application/json") w.Write(data) } // handleStats handles stats requests against the Kubelet func (s *Server) handleStats(w http.ResponseWriter, req *http.Request) { s.serveStats(w, req) } // handleLogs handles logs requests against the Kubelet func (s *Server) handleLogs(w http.ResponseWriter, req *http.Request) { s.host.ServeLogs(w, req) } // handleSpec handles spec requests against the Kubelet func (s *Server) handleSpec(w http.ResponseWriter, req *http.Request) { info, err := s.host.GetMachineInfo() if err != nil { s.error(w, err) return } data, err := json.Marshal(info) if err != nil { s.error(w, err) return } w.Header().Add("Content-type", "application/json") w.Write(data) } // ServeHTTP responds to HTTP requests on the Kubelet func (s *Server) ServeHTTP(w http.ResponseWriter, req *http.Request) { defer httplog.MakeLogged(req, &w).StacktraceWhen( httplog.StatusIsNot( http.StatusOK, http.StatusNotFound, ), ).Log() s.mux.ServeHTTP(w, req) </ins> } <ins> // serveStats implements stats logic </ins> func (s *Server) serveStats(w http.ResponseWriter, req *http.Request) { // /stats/<podfullname>/<containerName> components := strings.Split(strings.TrimPrefix(path.Clean(req.URL.Path), "/"), "/")

Discussion:
The Kubelet REST end-point has turned into a complicated switch-case code block that is harder to maintain overtime. The Kubelet should move to a http.ServeMux pattern and register handler functions to a pattern.
I am working on a PR to submit in next couple of days that will make this change, so feel free to assign to me if possible.
Tagging because I asked for this in one of his PRs
This one is also under my radar. If no one had time, feel free to assign it to me too.
I have a branch in progress. Feel free to offer feedback on it when I submit. Sent from my iPhone