code: func (a *authenticator) logoutHandler(w http.ResponseWriter, req *http.Request) {
  	decoder := json.NewDecoder(req.Body)
  	var credentials credentials
  	err := decoder.Decode(&credentials)
  	if err != nil {
  		errStr := fmt.Sprintf("500 internal server error: failed to decode json: %v", err)
  		a.formatter.Text(w, http.StatusInternalServerError, errStr)
  		return
  	}
  
  	a.userDb.SetLogoutTime(credentials.Username)
  	a.log.Debugf("user %s was logged out", credentials.Username)
  }
docs: // Removes token endpoint from the DB. During processing, token will not be found and will be considered as invalid.