func()

in providers/google.go [273:314]


func (p *GoogleProvider) redeemRefreshToken(refreshToken string) (token string, expires time.Duration, err error) {
	// https://developers.google.com/identity/protocols/OAuth2WebServer#refresh
	params := url.Values{}
	params.Add("client_id", p.ClientID)
	params.Add("client_secret", p.ClientSecret)
	params.Add("refresh_token", refreshToken)
	params.Add("grant_type", "refresh_token")
	var req *http.Request
	req, err = http.NewRequest("POST", p.RedeemURL.String(), bytes.NewBufferString(params.Encode()))
	if err != nil {
		return
	}
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		return
	}
	var body []byte
	body, err = ioutil.ReadAll(resp.Body)
	resp.Body.Close()
	if err != nil {
		return
	}

	if resp.StatusCode != 200 {
		err = fmt.Errorf("got %d from %q %s", resp.StatusCode, p.RedeemURL.String(), body)
		return
	}

	var data struct {
		AccessToken string `json:"access_token"`
		ExpiresIn   int64  `json:"expires_in"`
	}
	err = json.Unmarshal(body, &data)
	if err != nil {
		return
	}
	token = data.AccessToken
	expires = time.Duration(data.ExpiresIn) * time.Second
	return
}