http NewRequest获得意外字符

Question

I try to parse a page with this code :

client := &http.Client{}
profile := getEpiURL(login)

log.Print("Fetch " + profile)
req, err := http.NewRequest("GET", profile, nil)
if err != nil {
    log.Fatal(err)
}
req.AddCookie(cookieSessionIntra)
body, _ := httputil.DumpRequestOut(req, true)

With this as getEpiURL function :

func getEpiURL(login string) (url string) {
    url = "https://********/user/" + login + "/?format=json"
    return
}

And when i look at the output the profile variable is good, but in the Request it seems obviously wrong...

2016/11/24 12:53:53 Fetch https://********/user/le****in-vi**rd@e*******/?format=json

Then the debug for the request prints me :

GET /user/%00l%*****0o%*00.%00c***0-%00v%00i%0*a%00r%00d%00@%00e%00i%00t%00e%00c%0***0.%0***00/?format=json HTTP/1.1 Host: ****** User-Agent: Go-http-client/1.1 Cookie: PHPSESSID=********* Accept-Encoding: gzip

Answer 1

I think your original string somehow contains NUL characters. Try this out in the playground:

func main() {
    req, err := http.NewRequest("GET", "https://some/normal/path", nil)
    if err != nil {
        log.Fatal(err)
    }
    body, _ := httputil.DumpRequestOut(req, true)
    fmt.Printf("Hello, playground, %q", body)
}

You'll get:

"GET /normal/path HTTP/1.1
Host: some...

Now try it with a string in which you inserted NUL characters:

req, err := http.NewRequest("GET", "https://some/\000n\000o\000rmal/path", nil)

...

"GET /%00n%00o%00rmal/path HTTP/1.1
Host: some...

Not quite sure how your string ended up containing those. Read more about percent encoding.