func()

in clientcredentials/clientcredentials.go [90:120]

• 28 lines of code
• 7 McCabe index (conditional complexity)

func (c *tokenSource) Token() (*oauth2.Token, error) {
	v := url.Values{
		"grant_type": {"client_credentials"},
	}
	if len(c.conf.Scopes) > 0 {
		v.Set("scope", strings.Join(c.conf.Scopes, " "))
	}
	for k, p := range c.conf.EndpointParams {
		// Allow grant_type to be overridden to allow interoperability with
		// non-compliant implementations.
		if _, ok := v[k]; ok && k != "grant_type" {
			return nil, fmt.Errorf("oauth2: cannot overwrite parameter %q", k)
		}
		v[k] = p
	}

	tk, err := internal.RetrieveToken(c.ctx, c.conf.ClientID, c.conf.ClientSecret, c.conf.TokenURL, v, internal.AuthStyle(c.conf.AuthStyle))
	if err != nil {
		if rErr, ok := err.(*internal.RetrieveError); ok {
			return nil, (*oauth2.RetrieveError)(rErr)
		}
		return nil, err
	}
	t := &oauth2.Token{
		AccessToken:  tk.AccessToken,
		TokenType:    tk.TokenType,
		RefreshToken: tk.RefreshToken,
		Expiry:       tk.Expiry,
	}
	return t.WithExtra(tk.Raw), nil
}