Set headers in JSON get request - json

Question

I'm getting JSON resonse from an external API with the following way:
func Request(url string, contentType string) []byte {
resp, err := http.Get(url)
resp.Header.Set("Content-Type", contentType)
if err != nil {
log.Fatal(err)
}
body, err := ioutil.ReadAll(resp.Body)
resp.Body.Close()
if err != nil {
log.Fatal(err)
}
return body
}
url := fmt.Sprintf("https://example.com/api/category/%s", category)
contentType := "application/json"
body := Request(url, contentType)
res := &JSONRespStruct{}
err := json.Unmarshal([]byte(body), res)
if err != nil {
log.Fatal(err)
}
The problem if I start to benchmark my site with go-wrk, the server crashes with the following error message:
2018/01/02 12:13:35 invalid character '<' looking for beginning of value
I think the code try to parse the JSON response as HTML. How I can force to get the response as a JSON?

Answer 1

You probably want to set the header on the request. Setting the header on the response has no impact.
func Request(url string, contentType string) []byte {
req, err := http.NewRequest("GET", url, nil)
if err != nil {
log.Fatal(err)
}
req.Header.Set("Content-Type", contentType)
resp, err := http.DefaultClient.Do(req)
if err != nil {
log.Fatal(err)
}
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
log.Fatal(err)
}
return body
}