[TOC]
> [参考文档](https://github.com/gorilla/mux)
## 安装`
`go get -u github.com/gorilla/mux`
## 实例
### path 解析
```
r := mux.NewRouter()
r.HandleFunc("/products/{key}", ProductHandler)
r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler)
r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
func ArticlesCategoryHandler(w http.ResponseWriter, r *http.Request) {
vars := mux.Vars(r)
w.WriteHeader(http.StatusOK)
fmt.Fprintf(w, "Category: %v\n", vars["category"])
}
```
### 链式匹配
```
//在NewRouter 进行链式调用
r := mux.NewRouter()
// Only matches if domain is "www.example.com".
r.Host("www.example.com")
// Matches a dynamic subdomain.
r.Host("{subdomain:[a-z]+}.example.com")
//在handle 中链式调用
r.HandleFunc("/products", ProductsHandler).
Host("www.example.com").
Methods("GET", "POST").
Schemes("http").
Queries("key", "value")
```
### 子路由
```
r := mux.NewRouter()
s := r.PathPrefix("/products").Subrouter()
s.HandleFunc("/", ProductsHandler)
s.HandleFunc("/{key}/", ProductHandler)
s.HandleFunc("/{key}/details", ProductDetailsHandler)
```
### 静态文件
```
func main() {
var dir string
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))))
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())
}
```
### 单页面应用
main.go
```
package main
import (
"encoding/json"
"log"
"net/http"
"os"
"path/filepath"
"time"
"github.com/gorilla/mux"
)
type spaHandler struct {
staticPath string
indexPath string
}
func (h spaHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
path, err := filepath.Abs(r.URL.Path)
if err != nil {
http.Error(w, err.Error(), http.StatusBadRequest)
return
}
path = filepath.Join(h.staticPath, path)
_, err = os.Stat(path)
if os.IsNotExist(err) {
http.ServeFile(w, r, filepath.Join(h.staticPath, h.indexPath))
return
} else if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
http.FileServer(http.Dir(h.staticPath)).ServeHTTP(w, r)
}
func main() {
router := mux.NewRouter()
router.HandleFunc("/api/health", func(w http.ResponseWriter, r *http.Request) {
json.NewEncoder(w).Encode(map[string]bool{"ok": true})
})
spa := spaHandler{staticPath: "build", indexPath: "index.html"}
router.PathPrefix("/").Handler(spa)
srv := &http.Server{
Handler: router,
Addr: "127.0.0.1:8000",
WriteTimeout: 15 * time.Second,
ReadTimeout: 15 * time.Second,
}
log.Fatal(srv.ListenAndServe())
}
```
### 生成url
实例1
```
// 给 handle 取名为 article
r := mux.NewRouter()
r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
Name("article")
// 生成url
url, err := r.Get("article").URL("category", "technology", "id", "42")
// /articles/technology/42
```
实例2
```
r := mux.NewRouter()
r.Host("{subdomain}.example.com").
Path("/articles/{category}/{id:[0-9]+}").
Queries("filter", "{filter}").
HandlerFunc(ArticleHandler).
Name("article")
// url.String() will be "http://news.example.com/articles/technology/42?filter=gorilla"
url, err := r.Get("article").URL("subdomain", "news",
"category", "technology",
"id", "42",
"filter", "gorilla")
```
### 优雅关闭
main.go
```
package main
import (
"context"
"flag"
"log"
"net/http"
"os"
"os/signal"
"time"
"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()
srv := &http.Server{
Addr: "0.0.0.0:8080",
WriteTimeout: time.Second * 15,
ReadTimeout: time.Second * 15,
IdleTimeout: time.Second * 60,
}
go func() {
if err := srv.ListenAndServe(); err != nil {
log.Println(err)
}
}()
c := make(chan os.Signal, 1)
signal.Notify(c, os.Interrupt)
ctx, cancel := context.WithTimeout(context.Background(), wait)
defer cancel()
srv.Shutdown(ctx)
log.Println("shutting down")
os.Exit(0)
}
```
### 中间件
实例1
```
func loggingMiddleware(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
// Do stuff here
log.Println(r.RequestURI)
// Call the next handler, which can be another middleware in the chain, or the final handler.
next.ServeHTTP(w, r)
})
}
r := mux.NewRouter()
r.HandleFunc("/", handler)
r.Use(loggingMiddleware)
```
实例2
```
// Define our struct
type authenticationMiddleware struct {
tokenUsers map[string]string
}
// Initialize it somewhere
func (amw *authenticationMiddleware) Populate() {
amw.tokenUsers["00000000"] = "user0"
amw.tokenUsers["aaaaaaaa"] = "userA"
amw.tokenUsers["05f717e5"] = "randomUser"
amw.tokenUsers["deadbeef"] = "user0"
}
// Middleware function, which will be called for each request
func (amw *authenticationMiddleware) Middleware(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
token := r.Header.Get("X-Session-Token")
if user, found := amw.tokenUsers[token]; found {
// We found the token in our map
log.Printf("Authenticated user %s\n", user)
// Pass down the request to the next middleware (or final handler)
next.ServeHTTP(w, r)
} else {
// Write an error and stop the handler chain
http.Error(w, "Forbidden", http.StatusForbidden)
}
})
}
r := mux.NewRouter()
r.HandleFunc("/", handler)
amw := authenticationMiddleware{}
amw.Populate()
r.Use(amw.Middleware)
```
### 跨域请求 CORS Requests
main.go
```
package main
import (
"net/http"
"github.com/gorilla/mux"
)
func main() {
r := mux.NewRouter()
// IMPORTANT: you must specify an OPTIONS method matcher for the middleware to set CORS headers
r.HandleFunc("/foo", fooHandler).Methods(http.MethodGet, http.MethodPut, http.MethodPatch, http.MethodOptions)
r.Use(mux.CORSMethodMiddleware(r))
http.ListenAndServe(":8080", r)
}
func fooHandler(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Access-Control-Allow-Origin", "*")
if r.Method == http.MethodOptions {
return
}
w.Write([]byte("foo"))
}
```
### handle 测试
测试1
endpoints.go
```
package main
func HealthCheckHandler(w http.ResponseWriter, r *http.Request) {
// A very simple health check.
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(http.StatusOK)
// In the future we could report back on the status of our DB, or our cache
// (e.g. Redis) by performing a simple PING, and include them in the response.
io.WriteString(w, `{"alive": true}`)
}
func main() {
r := mux.NewRouter()
r.HandleFunc("/health", HealthCheckHandler)
log.Fatal(http.ListenAndServe("localhost:8080", r))
}
```
endpoints_test.go
```
package main
import (
"net/http"
"net/http/httptest"
"testing"
)
func TestHealthCheckHandler(t *testing.T) {
// Create a request to pass to our handler. We don't have any query parameters for now, so we'll
// pass 'nil' as the third parameter.
req, err := http.NewRequest("GET", "/health", nil)
if err != nil {
t.Fatal(err)
}
// We create a ResponseRecorder (which satisfies http.ResponseWriter) to record the response.
rr := httptest.NewRecorder()
handler := http.HandlerFunc(HealthCheckHandler)
// Our handlers satisfy http.Handler, so we can call their ServeHTTP method
// directly and pass in our Request and ResponseRecorder.
handler.ServeHTTP(rr, req)
// Check the status code is what we expect.
if status := rr.Code; status != http.StatusOK {
t.Errorf("handler returned wrong status code: got %v want %v",
status, http.StatusOK)
}
// Check the response body is what we expect.
expected := `{"alive": true}`
if rr.Body.String() != expected {
t.Errorf("handler returned unexpected body: got %v want %v",
rr.Body.String(), expected)
}
}
```
测试2
endpoints.go
```
func main() {
r := mux.NewRouter()
// A route with a route variable:
r.HandleFunc("/metrics/{type}", MetricsHandler)
log.Fatal(http.ListenAndServe("localhost:8080", r))
}
```
endpoints_test.go
```
func TestMetricsHandler(t *testing.T) {
tt := []struct{
routeVariable string
shouldPass bool
}{
{"goroutines", true},
{"heap", true},
{"counters", true},
{"queries", true},
{"adhadaeqm3k", false},
}
for _, tc := range tt {
path := fmt.Sprintf("/metrics/%s", tc.routeVariable)
req, err := http.NewRequest("GET", path, nil)
if err != nil {
t.Fatal(err)
}
rr := httptest.NewRecorder()
// Need to create a router that we can pass the request through so that the vars will be added to the context
router := mux.NewRouter()
router.HandleFunc("/metrics/{type}", MetricsHandler)
router.ServeHTTP(rr, req)
// In this case, our MetricsHandler returns a non-200 response
// for a route variable it doesn't know about.
if rr.Code == http.StatusOK && !tc.shouldPass {
t.Errorf("handler should have failed on routeVariable %s: got %v want %v",
tc.routeVariable, rr.Code, http.StatusOK)
}
}
}
```