Missing last character from X-Endpoint-Api-Userinfo

Google Cloud Serverless Applications
1

Please see my previous post for more context.

I’m getting the header from Google Cloud Endpoint Service and reading it inside a Go Google Cloud Function.

It looks very strange that I have to add a “}” to make it works!

My commit contains the following code

authuserinfo := string(r.Header.Get("X-Endpoint-Api-Userinfo"))
	userinfo, _ := b64.StdEncoding.DecodeString(authuserinfo)
	var authperm struct {
		Iss string `json:"iss"`
		Sub string `json:"sub"`
		Aud []string `json:"aud"`
		Iat int `json:"iat"`
		Exp int `json:"exp"`
		Azp string `json:"azp"`
		Scope string `json:"scope"`
		Permissions []string `json:"permissions"`
	}
	if permerr := json.Unmarshal([]byte(string(userinfo)+"}"), &authperm); permerr != nil {
		switch permerr {
		case io.EOF:
			fmt.Fprint(w, "no auth permissions")
			return
		default:
			fmt.Fprint(w, permerr.Error() + " from " + string(userinfo) )
			return
		}
	}
2

Found the answer from this reply of a Google Software Engineer.

“This is a documentation error. It is base64url encoded, not base64 encoded.”

But solved with base64.RawURLEncoding according to this comment from the above thread.