The ideal way is not to use ioutil.ReadAll
, but rather use a decoder on the reader directly. Here’s a nice function that gets a url and decodes its response onto a target
structure.
var myClient = &http.Client{Timeout: 10 * time.Second}
func getJson(url string, target interface{}) error {
r, err := myClient.Get(url)
if err != nil {
return err
}
defer r.Body.Close()
return json.NewDecoder(r.Body).Decode(target)
}
Example use:
type Foo struct {
Bar string
}
func main() {
foo1 := new(Foo) // or &Foo{}
getJson("http://example.com", foo1)
println(foo1.Bar)
// alternately:
foo2 := Foo{}
getJson("http://example.com", &foo2)
println(foo2.Bar)
}
You should not be using the default *http.Client
structure in production as this answer originally demonstrated! (Which is what http.Get
/etc call to). The reason is that the default client has no timeout set; if the remote server is unresponsive, you’re going to have a bad day.