package dyndns import ( "errors" "io/ioutil" "net/http" ) // Urls contains a set of mirrors in which a // raw IP string can be retreived. It is exported // for the intent of modification. var ( Urls = []string{"http://myexternalip.com/raw"} ) func tryMirror(url string) (string, error) { resp, err := http.Get(url) if err != nil { return "", err } defer resp.Body.Close() contents, err := ioutil.ReadAll(resp.Body) if err != nil { return "", err } return string(contents), nil } // Retrieves the external facing IP Address. // If multiple mirrors are provided in Urls, // it will try each one (in order), should // preceding mirrors fail. func GetExternalIP() (string, error) { for _, url := range Urls { resp, err := tryMirror(url) if err == nil { return resp, err } } return "", errors.New("Could not retreive external IP") }