standard/mux/a.go

package main

import (
	"flag"
	"fmt"
	"github.com/gorilla/mux"
	"net/http"
	"strings"
)

func Run() {
	var dir string
	flag.StringVar(&dir, "dir", ".", "the directory to serve files from. Defaults to the current dir")
	flag.Parse()                                                                                   // 初始化Router
	r := mux.NewRouter()                                                                           // 静态文件路由
	r.PathPrefix("/static/").Handler(http.StripPrefix("/static/", http.FileServer(http.Dir(dir)))) // 普通路由
	r.HandleFunc("/", HomeHandler)                                                                 // 指定host
	r.HandleFunc("/host", HostHandler).Host("localhost")                                           // 带变量的url路由
	r.HandleFunc("/users/{id}", GetUserHandler).Methods("Get").Name("user")

	url, _ := r.Get("user").URL("id", "5")
	fmt.Println("user url: ", url.String()) // 遍历已注册的路由
	r.Walk(func(route *mux.Route, router *mux.Router, ancestors []*mux.Route) error {
		pathTemplate, err := route.GetPathTemplate()
		if err == nil {
			fmt.Println("ROUTE:", pathTemplate)
		}
		pathRegexp, err := route.GetPathRegexp()
		if err == nil {
			fmt.Println("Path regexp:", pathRegexp)
		}
		queriesTemplates, err := route.GetQueriesTemplates()
		if err == nil {
			fmt.Println("Queries templates:", strings.Join(queriesTemplates, ","))
		}
		queriesRegexps, err := route.GetQueriesRegexp()
		if err == nil {
			fmt.Println("Queries regexps:", strings.Join(queriesRegexps, ","))
		}
		methods, err := route.GetMethods()
		if err == nil {
			fmt.Println("Methods:", strings.Join(methods, ","))
		}
		fmt.Println()
		return nil
	})

	r.Use(TestMiddleware)
	http.ListenAndServe(":3000", r)
}
func HomeHandler(w http.ResponseWriter, r *http.Request) {
	w.WriteHeader(http.StatusOK)
	fmt.Fprintf(w, "this is home")
}
func HostHandler(w http.ResponseWriter, r *http.Request) {
	w.WriteHeader(http.StatusOK)
	fmt.Fprintf(w, "the host is localhost")
}
func GetUserHandler(w http.ResponseWriter, r *http.Request) {
	vars := mux.Vars(r)
	w.WriteHeader(http.StatusOK)

	fmt.Fprint(w, "this is get user, and the user id is ", vars["id"])
}
func TestMiddleware(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { // Do stuff here
		fmt.Println("middleware print: ", r.RequestURI) // Call the next handler, which can be another middleware in the chain, or the final handler.
		next.ServeHTTP(w, r)
	})
}