http请求后如何获得响应

Question

I'm studying Go and am a real newbie in this field.

I am facing a problem when I try to copy some value.

What I am doing is:

1. I want to get some response in [response] using httpRequest.

httpClient := &http.Client{}
response, err := httpClient.Do(req)
if err != nil {
   panic(err)
}

1. After that, I want to save the stored value in response at 'origin.txt'

origin_ ,_:= ioutil.ReadAll(response.Body)
f_, err := os.Create("origin.txt")
f_.Write(origin_);

1. And I want to get a specific value by using goquery package.

doc, err := goquery.NewDocumentFromReader(response.Body)
if err != nil {
    log.Fatal(err)
}
doc.Find(".className").Each(func(i int, s *goquery.Selection) {
    w.WriteString("============" + strconv.Itoa(i) + "============")
    s.Find("tr").Each(func(i int, s_ *goquery.Selection) {
    fmt.Println(s_.Text())
    w.WriteString(s_.Text())    
    })
}

)

But in this case, I can get a value exactly what I want from 2) but cannot get anything from 3).

At first, I think the problem is, the response object at 3) is affected by 2) action. Because it is a reference object.

So I tried to copy it to another object and then do it again.

origin := *response

but, I got the same result as first.

What should I do? How can I assign a reference value to another one by its value?

Should I request it twice for each attempt?