Go语言HttpRouter路由使用方法详解

package main

import (
    "fmt"
    "github.com/julienschmidt/httprouter"
    "net/http"
    "log"
)

func Index(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
    fmt.Fprint(w, "Welcome!\n")
}

func Hello(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
    fmt.Fprintf(w, "hello, %s!\n", ps.ByName("name"))
}

func main() {
    router := httprouter.New()
    router.GET("/", Index)
    router.GET("/hello/:name", Hello)

    log.Fatal(http.ListenAndServe(":8080", router))
}

go get github.com/julienschmidt/httprouter

go run xxx.go

Variables
func CleanPath(p string) string
type Handle
type Param
type Params
	func ParamsFromContext(ctx context.Context) Params
	func (ps Params) ByName(name string) string
type Router
	func New() *Router
	func (r *Router) DELETE(path string, handle Handle)
	func (r *Router) GET(path string, handle Handle)
	func (r *Router) HEAD(path string, handle Handle)
	func (r *Router) Handle(method, path string, handle Handle)
	func (r *Router) Handler(method, path string, handler http.Handler)
	func (r *Router) HandlerFunc(method, path string, handler http.HandlerFunc)
	func (r *Router) Lookup(method, path string) (Handle, Params, bool)
	func (r *Router) OPTIONS(path string, handle Handle)
	func (r *Router) PATCH(path string, handle Handle)
	func (r *Router) POST(path string, handle Handle)
	func (r *Router) PUT(path string, handle Handle)
	func (r *Router) ServeFiles(path string, root http.FileSystem)
	func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request)

type Handle func(http.ResponseWriter, *http.Request, Params)
    Handle is a function that can be registered to a route to handle HTTP
    requests. Like http.HandlerFunc, but has a third parameter for the values of
    wildcards (variables).

func Index(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
    fmt.Fprint(w, "Welcome!\n")
}

func Hello(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
    fmt.Fprintf(w, "hello, %s!\n", ps.ByName("name"))
}

type Router struct {}
func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request)

func (r *Router) Handle(method, path string, handle Handle)
func (r *Router) Handler(method, path string, handler http.Handler)
func (r *Router) HandlerFunc(method, path string, handler http.HandlerFunc)

func (r *Router) DELETE(path string, handle Handle)
func (r *Router) GET(path string, handle Handle)
func (r *Router) HEAD(path string, handle Handle)
func (r *Router) OPTIONS(path string, handle Handle)
func (r *Router) PATCH(path string, handle Handle)
func (r *Router) POST(path string, handle Handle)
func (r *Router) PUT(path string, handle Handle)

router := httprouter.New()
router.GET("/", Index)
router.GET("/hello/:name", Hello)

type Param struct {
    Key   string
    Value string
}
Param is a single URL parameter, consisting of a key and a value.

type Params []Param
Params is a Param-slice, as returned by the router. The slice is ordered, the first URL parameter is also the first slice value. It is therefore safe to read values by the index.

func (ps Params) ByName(name string) string
ByName returns the value of the first Param which key matches the given name. If no matching Param is found, an empty string is returned.

router.GET("/hello/:name", Hello)

Param{
	Key: "name",
	Value: "abc",
}

func Hello(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
    fmt.Fprintf(w, "hello, %s!\n", ps.ByName("name"))
}

router.GET("/hello/:name", Hello)

ps[0].Key
ps[0].Value

Syntax    Type
:name     named parameter
*name     catch-all parameter

Path: /blog/:category/:post

/blog/go/request-routers            match: category="go", post="request-routers"
/blog/go/request-routers/           no match, but the router would redirect
/blog/go/                           no match
/blog/go/request-routers/comments   no match

Path: /files/*filepath

/files/                             match: filepath="/"
/files/LICENSE                      match: filepath="/LICENSE"
/files/templates/article.html       match: filepath="/templates/article.html"
/files                              no match, but the router would redirect

type Router struct {
    RedirectTrailingSlash bool
	...
}

注册路径：/blog/:category/:post
请求URL路径：/blog/go/request-routers/

注册路径：/blog/:category
请求URL路径：/blog/go

注册路径：/files/*filepath
请求URL路径：/files

func (r *Router) Lookup(method, path string) (Handle, Params, bool)