| // Copyright Istio Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package main |
| |
| import ( |
| "context" |
| "fmt" |
| "log" |
| "net/http" |
| "os" |
| "os/signal" |
| "syscall" |
| ) |
| |
| import ( |
| "github.com/gorilla/mux" |
| ) |
| |
| const ( |
| addr = ":8080" |
| |
| projID = "test-project" |
| projNumber = "123456789" |
| instance = "test-instance" |
| instID = "987654321" |
| zone = "us-west1-c" |
| |
| metaPrefix = "/computeMetadata/v1" |
| projIDPath = metaPrefix + "/project/project-id" |
| projNumberPath = metaPrefix + "/project/numeric-project-id" |
| instIDPath = metaPrefix + "/instance/id" |
| instancePath = metaPrefix + "/instance/name" |
| zonePath = metaPrefix + "/instance/zone" |
| attrKey = "attribute" |
| attrPath = metaPrefix + "/instance/attributes/{" + attrKey + "}" |
| ) |
| |
| var instAttrs = map[string]string{ |
| "instance-template": "some-template", |
| "created-by": "some-creator", |
| } |
| |
| func checkMetadataHeaders(next http.Handler) http.Handler { |
| return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { |
| log.Println("request for: " + r.URL.Path) |
| w.Header().Add("Server", "Metadata Server for VM (Fake)") |
| w.Header().Add("Metadata-Flavor", "Google") |
| |
| flavor := r.Header.Get("Metadata-Flavor") |
| if flavor == "" && r.RequestURI != "/" { |
| http.Error(w, http.StatusText(http.StatusForbidden), http.StatusForbidden) |
| w.Header().Set("Content-Type", "text/html; charset=UTF-8") |
| log.Println("forbidden: " + r.URL.Path) |
| return |
| } |
| |
| next.ServeHTTP(w, r) |
| }) |
| } |
| |
| func handleAttrs(w http.ResponseWriter, r *http.Request) { |
| vars := mux.Vars(r) |
| |
| if val, ok := instAttrs[vars[attrKey]]; ok { |
| fmt.Fprint(w, val) |
| return |
| } |
| |
| http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound) |
| } |
| |
| func main() { |
| r := mux.NewRouter() |
| r.Use(checkMetadataHeaders) |
| r.HandleFunc(projIDPath, func(w http.ResponseWriter, r *http.Request) { fmt.Fprint(w, projID) }).Methods("GET") |
| r.HandleFunc(projNumberPath, func(w http.ResponseWriter, r *http.Request) { fmt.Fprint(w, projNumber) }).Methods("GET") |
| r.HandleFunc(instIDPath, func(w http.ResponseWriter, r *http.Request) { fmt.Fprint(w, instID) }).Methods("GET") |
| r.HandleFunc(instancePath, func(w http.ResponseWriter, r *http.Request) { fmt.Fprint(w, instance) }).Methods("GET") |
| r.HandleFunc(zonePath, func(w http.ResponseWriter, r *http.Request) { fmt.Fprint(w, zone) }).Methods("GET") |
| r.HandleFunc(attrPath, handleAttrs).Methods("GET") |
| http.Handle("/", r) |
| |
| srv := &http.Server{Addr: addr} |
| |
| done := make(chan os.Signal, 1) |
| signal.Notify(done, os.Interrupt, syscall.SIGINT, syscall.SIGTERM) |
| |
| go func() { |
| if err := srv.ListenAndServe(); err != http.ErrServerClosed { |
| log.Fatalf("listen: %v\n", err) |
| } |
| }() |
| |
| log.Println("GCE metadata server started (" + addr + ")") |
| <-done |
| log.Println("GCE metadata server stopped.") |
| |
| if err := srv.Shutdown(context.Background()); err != nil { |
| log.Fatalf("GCE Metadata Shutdown Failed: %+v", err) |
| } |
| } |