errors.xql

(:
 :  Copyright (C) 2020 TEI Publisher Project Team
 :
 :  This program is free software: you can redistribute it and/or modify
 :  it under the terms of the GNU General Public License as published by
 :  the Free Software Foundation, either version 3 of the License, or
 :  (at your option) any later version.
 :
 :  This program is distributed in the hope that it will be useful,
 :  but WITHOUT ANY WARRANTY; without even the implied warranty of
 :  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 :  GNU General Public License for more details.
 :
 :  You should have received a copy of the GNU General Public License
 :  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 :)
xquery version "3.1";

(:~
 : Variables to indicate common errors
 :)
module namespace errors="http://e-editiones.org/roaster/errors";

(: router specific errors :)
declare variable $errors:REQUIRED_PARAM := xs:QName("errors:REQUIRED_PARAM");
declare variable $errors:OPERATION := xs:QName("errors:OPERATION");
declare variable $errors:BODY_CONTENT_TYPE := xs:QName("errors:BODY_CONTENT_TYPE");

(: common HTTP status codes :)
declare variable $errors:BAD_REQUEST := xs:QName("errors:BAD_REQUEST_400");
declare variable $errors:UNAUTHORIZED := xs:QName("errors:UNAUTHORIZED_401");
declare variable $errors:FORBIDDEN := xs:QName("errors:FORBIDDEN_403");
declare variable $errors:NOT_FOUND := xs:QName("errors:NOT_FOUND_404");
declare variable $errors:METHOD_NOT_ALLOWED := xs:QName("errors:METHOD_NOT_ALLOWED_405");
(: https://datatracker.ietf.org/doc/html/rfc7231#section-6.5.13 :)
declare variable $errors:UNSUPPORTED_MEDIA_TYPE := xs:QName("errors:UNSUPPORTED_MEDIA_TYPE_415");
(: https://datatracker.ietf.org/doc/html/rfc4918#section-11.2 :)
declare variable $errors:UNPROCESSABLE_ENTITY := xs:QName("errors:UNPROCESSABLE_ENTITY_422");
declare variable $errors:SERVER_ERROR := xs:QName("errors:SERVER_ERROR_500");

declare function errors:get-status-code-from-error($error as xs:QName) as xs:integer {
    switch($error)
        case $errors:REQUIRED_PARAM (: fall-through :)
        case $errors:BAD_REQUEST (: fall-through :)
        case $errors:BODY_CONTENT_TYPE return 400

        case $errors:UNAUTHORIZED return 401
        case $errors:FORBIDDEN return 403
        case $errors:NOT_FOUND return 404
        case $errors:METHOD_NOT_ALLOWED return 405
        case $errors:UNSUPPORTED_MEDIA_TYPE return 415
        case $errors:UNPROCESSABLE_ENTITY return 422

        case $errors:OPERATION (: fall-through :)
        case $errors:SERVER_ERROR return 500 (: no fall-through possible :)
        default return 500
};