Custom Middleware
/public/login.html
<html>
<head>
<title>Login</title>
</head>
<body>
<form class="form-signin" action="/login" method="post">
username
<input name="username" required autofocus>
password
<input type="password" name="password" required>
<button type="submit">Sign in</button>
</form>
</body>
</html>
middleware.go
package main
import (
"time"
"log"
"net/http"
"fmt"
"encoding/json"
"strings"
"path"
"crypto/hmac"
"crypto/sha1"
"io"
"encoding/hex"
)
type Middleware func(next HandlerFunc) HandlerFunc
func logHandler(next HandlerFunc) HandlerFunc {
return func(c *Context) {
fmt.Println("logHandler is called.")
t := time.Now()
next(c)
log.Printf("[%s] %q %v\n",
c.Request.Method,
c.Request.URL.String(),
time.Now().Sub(t))
}
}
func recoverHandler(next HandlerFunc) HandlerFunc {
return func(c *Context) {
fmt.Println("recoverHandler is called.")
defer func() {
if err := recover(); err != nil {
log.Printf("panic: %+v", err)
http.Error(c.ResponseWriter,
http.StatusText(http.StatusInternalServerError),
http.StatusInternalServerError)
}
}()
next(c)
}
}
func parseFormHandler(next HandlerFunc) HandlerFunc {
return func(c *Context) {
fmt.Println("HandlerFunc is called.")
c.Request.ParseForm()
fmt.Println(c.Request.PostForm)
for k, v := range c.Request.PostForm {
if len(v) > 0 {
c.Params[k] = v[0]
}
}
next(c)
}
}
func parseJsonBodyHandler(next HandlerFunc) HandlerFunc {
return func(c *Context) {
fmt.Println("parseJsonBodyHandler is called.")
var m map[string]interface{}
if json.NewDecoder(c.Request.Body).Decode(&m); len(m) > 0 {
for k, v := range m {
c.Params[k] = v
}
}
next(c)
}
}
func staticHandler(next HandlerFunc) HandlerFunc {
var (
dir = http.Dir(".")
indexFile = "index.html"
)
return func(c *Context) {
if c.Request.Method != "GET" && c.Request.Method != "HEAD" {
next(c)
return
}
file := c.Request.URL.Path
f, err := dir.Open(file)
if err != nil {
next(c)
return
}
defer f.Close()
fi, err := f.Stat()
if err != nil {
next(c)
return
}
if fi.IsDir() {
if !strings.HasSuffix(c.Request.URL.Path, "/") {
http.Redirect(c.ResponseWriter, c.Request, c.Request.URL.Path+"/", http.StatusFound)
return
}
file = path.Join(file, indexFile)
f, err = dir.Open(file)
if err != nil {
next(c)
return
}
defer f.Close()
fi, err = f.Stat()
if err != nil || fi.IsDir() {
next(c)
return
}
}
http.ServeContent(c.ResponseWriter, c.Request, file, fi.ModTime(), f)
}
}
const VerifyMessage = "verified"
func AuthHandler(next HandlerFunc) HandlerFunc {
ignore := []string{"/login", "public/index.html"}
return func(c *Context) {
for _, s := range ignore {
if strings.HasPrefix(c.Request.URL.Path, s) {
next(c)
return
}
if v, err := c.Request.Cookie("X_AUTH"); err == http.ErrNoCookie {
c.Redirect("/login")
} else if err != nil {
c.RenderError(http.StatusInternalServerError, err)
} else if Verify(VerifyMessage, v.Value) {
next(c)
return
}
}
c.Redirect("/login")
}
}
func Verify(message, sig string) bool {
return hmac.Equal([]byte(sig), []byte(Sign(message)))
}
func Sign(message string) string {
secretKey := []byte("snowdeer-simple-web-framework")
if len(secretKey) == 0 {
return ""
}
mac := hmac.New(sha1.New, secretKey)
io.WriteString(mac, message)
return hex.EncodeToString(mac.Sum(nil))
}
main.go
package main
import (
"fmt"
"time"
"net/http"
)
type User struct {
Id string
Name string
}
func main() {
fmt.Println("Simple Web Framework")
s := NewServer()
s.HandleFunc("GET", "/", func(c *Context) {
c.RenderTemplate("/public/index.html", map[string]interface{}{"time": time.Now()})
})
s.HandleFunc("GET", "/about", func(c *Context) {
fmt.Fprintln(c.ResponseWriter, "This is an about page.")
})
s.HandleFunc("GET", "/users/:id", func(c *Context) {
u := User{Id: c.Params["id"].(string)}
c.RenderXml(u)
})
s.HandleFunc("GET", "/users/:id/name/:name", func(c *Context) {
u := User{Id: c.Params["id"].(string),
Name: c.Params["name"].(string),
}
c.RenderJson(u)
})
s.HandleFunc("POST", "/users", func(c *Context) {
fmt.Fprintln(c.ResponseWriter, "Create user")
})
s.HandleFunc("GET", "/login", func(c *Context) {
c.RenderTemplate("/public/login.html", map[string]interface{}{"message": "로그인이 필요합니다."})
})
s.HandleFunc("POST", "/login", func(c *Context) {
if CheckLogin(c.Params["username"].(string), c.Params["password"].(string)) {
http.SetCookie(c.ResponseWriter, &http.Cookie{
Name: "X_AUTH",
Value: Sign(VerifyMessage),
Path: "/",
})
c.Redirect("/")
}
c.RenderTemplate("/public/login.html", map[string]interface{}{"message": "id 또는 password 오류"})
})
s.Use(AuthHandler)
s.Run(":8080")
}
func CheckLogin(username, password string) bool {
const (
USERNAME = "snowdeer"
PASSWORD = "1234"
)
return (username == USERNAME) && (password == PASSWORD)
}
