diff --git a/README.md b/README.md index 67a79e00..20094574 100644 --- a/README.md +++ b/README.md @@ -27,6 +27,7 @@ The name mux stands for "HTTP request multiplexer". Like the standard `http.Serv * [Static Files](#static-files) * [Registered URLs](#registered-urls) * [Walking Routes](#walking-routes) +* [Graceful Shutdown](#graceful-shutdown) * [Full Example](#full-example) --- @@ -45,11 +46,11 @@ Let's start registering a couple of URL paths and handlers: ```go func main() { - r := mux.NewRouter() - r.HandleFunc("/", HomeHandler) - r.HandleFunc("/products", ProductsHandler) - r.HandleFunc("/articles", ArticlesHandler) - http.Handle("/", r) + r := mux.NewRouter() + r.HandleFunc("/", HomeHandler) + r.HandleFunc("/products", ProductsHandler) + r.HandleFunc("/articles", ArticlesHandler) + http.Handle("/", r) } ``` @@ -68,9 +69,9 @@ The names are used to create a map of route variables which can be retrieved cal ```go func ArticlesCategoryHandler(w http.ResponseWriter, r *http.Request) { - vars := mux.Vars(r) - w.WriteHeader(http.StatusOK) - fmt.Fprintf(w, "Category: %v\n", vars["category"]) + vars := mux.Vars(r) + w.WriteHeader(http.StatusOK) + fmt.Fprintf(w, "Category: %v\n", vars["category"]) } ``` @@ -122,7 +123,7 @@ r.Queries("key", "value") ```go r.MatcherFunc(func(r *http.Request, rm *RouteMatch) bool { - return r.ProtoMajor == 0 + return r.ProtoMajor == 0 }) ``` @@ -243,24 +244,24 @@ request that matches "/static/*". This makes it easy to serve static files with ```go func main() { - var dir string + var dir string - flag.StringVar(&dir, "dir", ".", "the directory to serve files from. Defaults to the current dir") - flag.Parse() - r := mux.NewRouter() + flag.StringVar(&dir, "dir", ".", "the directory to serve files from. Defaults to the current dir") + flag.Parse() + r := mux.NewRouter() - // This will serve files under http://localhost:8000/static/ - r.PathPrefix("/static/").Handler(http.StripPrefix("/static/", http.FileServer(http.Dir(dir)))) + // This will serve files under http://localhost:8000/static/ + r.PathPrefix("/static/").Handler(http.StripPrefix("/static/", http.FileServer(http.Dir(dir)))) - srv := &http.Server{ - Handler: r, - Addr: "127.0.0.1:8000", - // Good practice: enforce timeouts for servers you create! - WriteTimeout: 15 * time.Second, - ReadTimeout: 15 * time.Second, - } + srv := &http.Server{ + Handler: r, + Addr: "127.0.0.1:8000", + // Good practice: enforce timeouts for servers you create! + WriteTimeout: 15 * time.Second, + ReadTimeout: 15 * time.Second, + } - log.Fatal(srv.ListenAndServe()) + log.Fatal(srv.ListenAndServe()) } ``` @@ -383,6 +384,69 @@ r.Walk(func(route *mux.Route, router *mux.Router, ancestors []*mux.Route) error }) ``` +### Graceful Shutdown + +Go 1.8 introduced the ability to [gracefully shutdown](https://golang.org/doc/go1.8#http_shutdown) a `*http.Server`. Here's how to do that alongside `mux`: + +```go +package main + +import ( + "context" + "flag" + "log" + "net/http" + "os" + "os/signal" + + "github.com/gorilla/mux" +) + +func main() { + var wait time.Duration + flag.DurationVar(&wait, "graceful-timeout", time.Second * 15, "the duration for which the server gracefully wait for existing connections to finish - e.g. 15s or 1m") + flag.Parse() + + r := mux.NewRouter() + // Add your routes as needed + + srv := &http.Server{ + Addr: "0.0.0.0:8080", + // Good practice to set timeouts to avoid Slowloris attacks. + WriteTimeout: time.Second * 15, + ReadTimeout: time.Second * 15, + IdleTimeout: time.Second * 60, + Handler: r, // Pass our instance of gorilla/mux in. + } + + // Run our server in a goroutine so that it doesn't block. + go func() { + if err := srv.ListenAndServe(); err != nil { + log.Println(err) + } + }() + + c := make(chan os.Signal, 1) + // We'll accept graceful shutdowns when quit via SIGINT (Ctrl+C) + // SIGKILL, SIGQUIT or SIGTERM (Ctrl+/) will not be caught. + signal.Notify(c, os.Interrupt) + + // Block until we receive our signal. + <-c + + // Create a deadline to wait for. + ctx, cancel := context.WithTimeout(ctx, wait) + // Doesn't block if no connections, but will otherwise wait + // until the timeout deadline. + srv.Shutdown(ctx) + // Optionally, you could run srv.Shutdown in a goroutine and block on + // <-ctx.Done() if your application should wait for other services + // to finalize based on context cancellation. + log.Println("shutting down") + os.Exit(0) +} +``` + ## Full Example Here's a complete, runnable example of a small `mux` based server: @@ -391,22 +455,22 @@ Here's a complete, runnable example of a small `mux` based server: package main import ( - "net/http" - "log" - "github.com/gorilla/mux" + "net/http" + "log" + "github.com/gorilla/mux" ) func YourHandler(w http.ResponseWriter, r *http.Request) { - w.Write([]byte("Gorilla!\n")) + w.Write([]byte("Gorilla!\n")) } func main() { - r := mux.NewRouter() - // Routes consist of a path and a handler function. - r.HandleFunc("/", YourHandler) + r := mux.NewRouter() + // Routes consist of a path and a handler function. + r.HandleFunc("/", YourHandler) - // Bind to a port and pass our router in - log.Fatal(http.ListenAndServe(":8000", r)) + // Bind to a port and pass our router in + log.Fatal(http.ListenAndServe(":8000", r)) } ```