英文:
How do I convert a Handle to a HandleFunc?
问题
我正在制作一个验证码，并且正在按照这里给出的示例进行操作。我需要修改示例代码，以便在我的应用程序中使用gorilla mux的路由，因为我的应用程序的其余部分都在使用它。但是我无论如何都无法弄清楚如何正确地路由第47行的路径。我在下面的代码中所做的更改导致没有生成验证码（示例本身正常工作）。为了测试，我甚至尝试了" http.HandleFunc("/captcha/", captchaHandler)"，但也不起作用。有什么建议吗？
package main
import (
"github.com/dchest/captcha"
"github.com/gorilla/mux"
"io"
"log"
"net/http"
"text/template"
)
var formTemplate = template.Must(template.New("example").Parse(formTemplateSrc))
func showFormHandler(w http.ResponseWriter, r *http.Request) {
if r.URL.Path != "/" {
http.NotFound(w, r)
return
}
d := struct {
CaptchaId string
}{
captcha.New(),
}
if err := formTemplate.Execute(w, &d); err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
}
}
func processFormHandler(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/html; charset=utf-8")
if !captcha.VerifyString(r.FormValue("captchaId"), r.FormValue("captchaSolution")) {
io.WriteString(w, "Wrong captcha solution! No robots allowed!\n")
} else {
io.WriteString(w, "Great job, human! You solved the captcha.\n")
}
io.WriteString(w, "<br><a href='/'>Try another one</a>")
}
func captchaHandler(w http.ResponseWriter, r *http.Request) {
captcha.Server(captcha.StdWidth, captcha.StdHeight)
}
type Routes []Route
type Route struct {
Method string
Pattern string
HandlerFunc http.HandlerFunc
}
func main() {
/*
http.HandleFunc("/", showFormHandler)
http.HandleFunc("/process", processFormHandler)
//http.HandleFunc("/captcha/", captchaHandler) // doesn't work
http.Handle("/captcha/", captcha.Server(captcha.StdWidth, captcha.StdHeight))
fmt.Println("Server is at localhost:8666")
if err := http.ListenAndServe(":8666", nil); err != nil {
log.Fatal(err)
}
*/
var routes = Routes{
Route{"GET", "/", showFormHandler},
Route{"POST", "/process", processFormHandler},
Route{"GET", "/captcha/", captchaHandler},
}
router := mux.NewRouter().StrictSlash(true)
for _, route := range routes {
var handler http.Handler
handler = route.HandlerFunc
router.Methods(route.Method).Path(route.Pattern).Handler(handler)
}
//router.Methods("GET").Path("/captcha/").HandlerFunc(captcha.Server(captcha.StdWidth, captcha.StdHeight))
port := ":8666"
log.Println("Listening at", port)
log.Fatal(http.ListenAndServe(port, router))
}
const formTemplateSrc = `<!doctype html>
<head><title>Captcha Example</title></head>
<body>
<script>
function setSrcQuery(e, q) {
var src = e.src;
var p = src.indexOf('?');
if (p >= 0) {
src = src.substr(0, p);
}
e.src = src + "?" + q
}
function playAudio() {
var le = document.getElementById("lang");
var lang = le.options[le.selectedIndex].value;
var e = document.getElementById('audio')
setSrcQuery(e, "lang=" + lang)
e.style.display = 'block';
e.autoplay = 'true';
return false;
}
function changeLang() {
var e = document.getElementById('audio')
if (e.style.display == 'block') {
playAudio();
}
}
function reload() {
setSrcQuery(document.getElementById('image'), "reload=" + (new Date()).getTime());
setSrcQuery(document.getElementById('audio'), (new Date()).getTime());
return false;
}
</script>
<select id="lang" onchange="changeLang()">
<option value="en">English</option>
<option value="ru">Russian</option>
<option value="zh">Chinese</option>
</select>
<form action="/process" method=post>
<p>Type the numbers you see in the picture below:</p>
<p><img id=image src="/captcha/{{.CaptchaId}}.png" alt="Captcha image"></p>
<a href="#" onclick="reload()">Reload</a> | <a href="#" onclick="playAudio()">Play Audio</a>
<audio id=audio controls style="display:none" src="/captcha/{{.CaptchaId}}.wav" preload=none>
You browser doesn't support audio.
<a href="/captcha/download/{{.CaptchaId}}.wav">Download file</a> to play it in the external player.
</audio>
<input type=hidden name=captchaId value="{{.CaptchaId}}"><br>
<input name=captchaSolution>
<input type=submit value=Submit>
</form>
`
编辑 #1：
更明确地说，"doesn't work"并不具有帮助性。它返回一个404错误。
编辑 #2：
GitHub上的示例代码正常工作...只有当我修改路由时，尝试生成验证码时才返回404错误。
英文:
I am making a captcha and am following the example given here. I need to modify the example to use gorilla mux's routing as the rest of my app uses that. For the life of me I can't figure out how to correctly route the path for line 47 of that example. What I have below results in no captcha generated...(the example itself works fine). For shits & giggles I've even tried "http.HandleFunc("/captcha/", captchaHandler)" but that doesn't work either. Any suggestions?
package main
import (
"github.com/dchest/captcha"
"github.com/gorilla/mux"
"io"
"log"
"net/http"
"text/template"
)
var formTemplate = template.Must(template.New("example").Parse(formTemplateSrc))
func showFormHandler(w http.ResponseWriter, r *http.Request) {
if r.URL.Path != "/" {
http.NotFound(w, r)
return
}
d := struct {
CaptchaId string
}{
captcha.New(),
}
if err := formTemplate.Execute(w, &d); err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
}
}
func processFormHandler(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/html; charset=utf-8")
if !captcha.VerifyString(r.FormValue("captchaId"), r.FormValue("captchaSolution")) {
io.WriteString(w, "Wrong captcha solution! No robots allowed!\n")
} else {
io.WriteString(w, "Great job, human! You solved the captcha.\n")
}
io.WriteString(w, "<br><a href='/'>Try another one</a>")
}
func captchaHandler(w http.ResponseWriter, r *http.Request) {
captcha.Server(captcha.StdWidth, captcha.StdHeight)
}
type Routes []Route
type Route struct {
Method string
Pattern string
HandlerFunc http.HandlerFunc
}
func main() {
/*
http.HandleFunc("/", showFormHandler)
http.HandleFunc("/process", processFormHandler)
//http.HandleFunc("/captcha/", captchaHandler) // doesn't work
http.Handle("/captcha/", captcha.Server(captcha.StdWidth, captcha.StdHeight))
fmt.Println("Server is at localhost:8666")
if err := http.ListenAndServe(":8666", nil); err != nil {
log.Fatal(err)
}
*/
var routes = Routes{
Route{"GET", "/", showFormHandler},
Route{"POST", "/process", processFormHandler},
Route{"GET", "/captcha/", captchaHandler},
}
router := mux.NewRouter().StrictSlash(true)
for _, route := range routes {
var handler http.Handler
handler = route.HandlerFunc
router.Methods(route.Method).Path(route.Pattern).Handler(handler)
}
//router.Methods("GET").Path("/captcha/").HandlerFunc(captcha.Server(captcha.StdWidth, captcha.StdHeight))
port := ":8666"
log.Println("Listening at", port)
log.Fatal(http.ListenAndServe(port, router))
}
const formTemplateSrc = `<!doctype html>
<head><title>Captcha Example</title></head>
<body>
<script>
function setSrcQuery(e, q) {
var src = e.src;
var p = src.indexOf('?');
if (p >= 0) {
src = src.substr(0, p);
}
e.src = src + "?" + q
}
function playAudio() {
var le = document.getElementById("lang");
var lang = le.options[le.selectedIndex].value;
var e = document.getElementById('audio')
setSrcQuery(e, "lang=" + lang)
e.style.display = 'block';
e.autoplay = 'true';
return false;
}
function changeLang() {
var e = document.getElementById('audio')
if (e.style.display == 'block') {
playAudio();
}
}
function reload() {
setSrcQuery(document.getElementById('image'), "reload=" + (new Date()).getTime());
setSrcQuery(document.getElementById('audio'), (new Date()).getTime());
return false;
}
</script>
<select id="lang" onchange="changeLang()">
<option value="en">English</option>
<option value="ru">Russian</option>
<option value="zh">Chinese</option>
</select>
<form action="/process" method=post>
<p>Type the numbers you see in the picture below:</p>
<p><img id=image src="/captcha/{{.CaptchaId}}.png" alt="Captcha image"></p>
<a href="#" onclick="reload()">Reload</a> | <a href="#" onclick="playAudio()">Play Audio</a>
<audio id=audio controls style="display:none" src="/captcha/{{.CaptchaId}}.wav" preload=none>
You browser doesn't support audio.
<a href="/captcha/download/{{.CaptchaId}}.wav">Download file</a> to play it in the external player.
</audio>
<input type=hidden name=captchaId value="{{.CaptchaId}}"><br>
<input name=captchaSolution>
<input type=submit value=Submit>
</form>
`
EDIT #1:
To be clearer "doesn't work" isn't helpful. It returns a 404 error.
EDIT #2:
The example on github works fine....its only when I modify the route that it returns a 404 when I try to generate a captcha.
答案1
得分: 2
你可以使用方法表达式将http.Handler h 转换为 http.HandlerFunc：
h.ServeHTTP
除了转换为HandlerFunc，你还可以直接使用路由的Handler方法注册Handler：
router.Methods("GET").Path("/captcha/").Handler(captcha.Server(captcha.StdWidth, captcha.StdHeight))
根据你的评论和编辑，我认为你想要一个前缀匹配而不是一个精确匹配：
router.Methods("GET").PathPrefix("/captcha/").Handler(captcha.Server(captcha.StdWidth, captcha.StdHeight))
英文:
You can convert the http.Handler h to a http.HandlerFunc using the method expression:
h.ServeHTTP
Instead of converting to a HandlerFunc, you can register the Handler directly using the route Handler method:
router.Methods("GET").Path("/captcha/").Handler(captcha.Server(captcha.StdWidth, captcha.StdHeight))
Based on your comments and edits, I think you want a prefix match instead of an exact match:
router.Methods("GET").PathPrefix("/captcha/").Handler(captcha.Server(captcha.StdWidth, captcha.StdHeight))
答案2
得分: 0
直接回答一个主题问题的方法就是按原样返回。
func(w http.ResponseWriter, r *http.Request, p map[string]string) {
youhttp.Handler().ServeHTTP(w, r)
}
英文:
The direct answer to a topic question is simply as is.
func(w http.ResponseWriter, r *http.Request, p map[string]string) {
youhttp.Handler().ServeHTTP(w, r)
}
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