views.py 文件源码

def exception_handler_mist(exc, request):
    """
    Here we catch exceptions and transform them to proper http responses
    This is a special pyramid view that gets triggered whenever an exception
    is raised from any other view. It catches all exceptions exc where
    isinstance(exc, context) is True.

    """
    # mongoengine ValidationError
    if isinstance(exc, me.ValidationError):
        trace = traceback.format_exc()
        log.warning("Uncaught me.ValidationError!\n%s", trace)
        return Response("Validation Error", 400)

    # mongoengine NotUniqueError
    if isinstance(exc, me.NotUniqueError):
        trace = traceback.format_exc()
        log.warning("Uncaught me.NotUniqueError!\n%s", trace)
        return Response("NotUniqueError", 409)

    # non-mist exceptions. that shouldn't happen! never!
    if not isinstance(exc, MistError):
        if not isinstance(exc, (me.ValidationError, me.NotUniqueError)):
            trace = traceback.format_exc()
            log.critical("Uncaught non-mist exception? WTF!\n%s", trace)
            return Response("Internal Server Error", 500)

    # mist exceptions are ok.
    log.info("MistError: %r", exc)

    # if it is a RedirectError, then send an HTTP Redirect
    if isinstance(exc, RedirectError):
        return HTTPFound(exc.url or '')

    # else translate it to HTTP response based on http_code attribute
    return Response(str(exc), exc.http_code)