code: func (user *User) OauthRedirectURL() string {
  	providerID := user.ctx.OAuthProvider().internalID()
  	if providerID == user.ctx.ServiceName {
  		return fmt.Sprintf("%s/auth/%s", Config.BaseURL, user.ctx.ServiceName)
  	}
  
  	return fmt.Sprintf("%s/auth/%s/%s", Config.BaseURL, user.ctx.ServiceName, providerID)
  }
docs: // OauthRedirectURL used in OAuth process as returning URL