POST data faild using http.NewRequest - forms

Question

I am trying to pass data from one golang service to another using http.NewRequest(). To do it I used following code:
httpClient := http.Client{}
userserviceUrl := "http://user:7071/checkemail"
form := url.Values{}
form.Set("uuid", uuid)
form.Set("email", email)
b := bytes.NewBufferString(form.Encode())
req, err := http.NewRequest("POST", userserviceUrl, b)
if err != nil {
log.Println(err)
}
opentracing.GlobalTracer().Inject(
validateEmailSpan.Context(),
opentracing.HTTPHeaders,
opentracing.HTTPHeadersCarrier(req.Header))
resp, err := httpClient.Do(req)
//_, err = http.PostForm("http://user:7071/checkemail", url.Values{"uuid": {uuid}, "email": {email}})
if err != nil {
log.Println("Couldnt verify email address user service sends an error : ", err)
}
defer resp.Body.Close()
I got this from Golang: http.NewRequest POST
When I try to dump received data from user service:
req.ParseForm()
log.Println("Form values : ", req.Form)
I get an empty map[]
Here I just try to inject tracing span to my request, previously I have used http.PostForm() to pass data, it worked perfectly. But I have no idea to pass tracing to it.

Answer 1

From the docs for ParseForm:
[...] when the Content-Type is not application/x-www-form-urlencoded, the request Body is not read, and r.PostForm is initialized to a non-nil, empty value.
PostForm sets the Content-Type automatically, but now you have to do it yourself:
req, err := http.NewRequest("POST", userserviceUrl, strings.NewReader(form.Encode()))
// TODO: handle error
req.Header.Set("Content-Type", "application/x-www-form-urlencoded")