Comment 1 by hip80763:

a temporary way to solve this is to use url.QueryEscape to process the Unicode text
before including them to the URL

Comment 2:

what makes you think that it doesn't work?
or put it another way, what do you mean by "unresponding"?
please give some details and make sure to provide
a reproducible test case as small as possible.

Status changed to WaitingForReply.

Comment 3:

Still waiting for a reply. What web browser are you using?
It is likely we should escape UTF-8 bytes in the redirect header though.

Labels changed: added priority-later, removed priority-triage.

Comment 4:

Labels changed: added size-m.

Comment 5:

Labels changed: added suggested.

Comment 6 by rick@boat-rockers.com:

I did some investigation on this issue:
https://groups.google.com/forum/?fromgroups=#!topic/golang-dev/Ml2QNDq9ElM
tl;dr - I couldn't reproduce it but escaping chars > 0x7F is required by the spec.
I can think of 3 options to fix this issue:
1) Handle encoding of the redirect Location header only
2) Automatically encode/decode all HTTP headers (to enforce the spec consistently)
3) Don't change code but document that users should make sure to encode/decode if
necessary
What is your preference?

Comment 7:

Probably option 2).  Unless that breaks something, but I can't imagine what.
Automatically encoding (when writing) at least seems safe.  Decoding seems riskier, but
probably(?) also fine.

Status changed to Accepted.

Comment 8:

Labels changed: added go1.1maybe, removed go1.1.

Comment 9:

Labels changed: added go1.2maybe, removed go1.1maybe.

Comment 10:

Labels changed: added go1.3, removed go1.2maybe.

Comment 11:

Labels changed: added release-go1.3.

Comment 12:

Labels changed: removed go1.3.

Comment 13:

Labels changed: added repo-main.

Comment 14:

Labels changed: added release-none, removed release-go1.3.

With the latest tip this seems to be working fine, unicode or not doesn't seem to be a problem anymore.

package main

import (
    "fmt"
    "log"
    "net/http"
)

func main() {
    http.HandleFunc("/中文字", func(w http.ResponseWriter, r *http.Request) {
        msg := fmt.Sprintf("Successful redirect. for method %s", r.Method)
        w.Write([]byte(msg))
    })
    http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
        http.Redirect(w, r, "http://localhost:8080/中文字", 302)
    })

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

 cat ~/bugs-golang/client.go
package main

import (
    "bytes"
    "fmt"
    "log"
    "net/http"
)

func main() {
    clnt := &http.Client{}

    req, err := http.NewRequest("GET", "http://localhost:8080/", nil)
    if err != nil {
        log.Fatalln(err)
    }

    resp, err := clnt.Do(req)
    if err != nil {
        log.Fatalln(err)
    }

    // Write response.
    var bufferGet bytes.Buffer
    resp.Write(&bufferGet)

    fmt.Println("--- GET RESPONSE ---")
    fmt.Println(string(bufferGet.Bytes()))
    fmt.Println("")
}

$ go run ~/bugs-golang/client.go
--- GET RESPONSE ---
HTTP/1.1 200 OK
Content-Length: 35
Content-Type: text/plain; charset=utf-8
Date: Mon, 18 Jan 2016 23:20:29 GMT

Successful redirect. for method GET

Will just add a test case to make sure that its validated all the time.

CL https://golang.org/cl/18732 mentions this issue.

I'm not sure https://golang.org/cl/18732 is correct. It seems like there should be some escaping happening. I don't think UTF-8 is allowed in headers.

Even if this "works" right now, it's just us testing our own misbehavior probably.

Any change needs to cite relevant parts of specs.

I'm not sure https://golang.org/cl/18732 is correct. It seems like there should be some escaping happening. I don't think UTF-8 is allowed in headers.

Even if this "works" right now, it's just us testing our own misbehavior probably.

Any change needs to cite relevant parts of specs.

You are right UTF-8 is not allowed.

The "Location" header field is used in some responses to refer to a
   specific resource in relation to the response.  The type of
   relationship is defined by the combination of request method and
   status code semantics.

     Location = URI-reference

From what i can read they should be escaped while doing a redirect since Location header is a URI. Not sure why it isn't happening though. Will see why this is not happening.

CL https://golang.org/cl/31732 mentions this issue.