exceptions.py 文件源码

def from_response(response, method, url):
    """Returns an instance of :class:`HttpError` or subclass based on response.

    :param response: instance of `requests.Response` class
    :param method: HTTP method used for request
    :param url: URL used for request
    """

    req_id = response.headers.get('X-openstack-request-id')
    # NOTE(hdd) true for older versions of nova and cinder
    if not req_id:
        req_id = response.headers.get('X-compute-request-id')

    kwargs = {
        'http_status': response.status_code,
        'response': response,
        'method': method,
        'url': url,
        'request_id': req_id
    }

    if 'retry_after' in response.headers:
        kwargs['retry_after'] = response.headers['retry_after']

    content_type = response.headers.get('Content-Type', "")
    if content_type.startswith('application/json'):
        try:
            body = response.json()
        except ValueError:
            pass
        else:
            if isinstance(body, dict):
                error = body.get(list(body)[0])
                if isinstance(error, dict):
                    kwargs['message'] = (error.get('message') or
                                         error.get('faultstring'))
                    kwargs['details'] = (error.get('details') or
                                         six.text_type(body))
    elif content_type.startswith("text/"):
        kwargs['details'] = getattr(response, 'text', '')

    try:
        cls = _code_map[response.status_code]
    except KeyError:
        # 5XX status codes are server errors
        if response.status_code >= http_client.INTERNAL_SERVER_ERROR:
            cls = HttpServerError
        # 4XX status codes are client request errors
        elif (http_client.BAD_REQUEST <= response.status_code <
              http_client.INTERNAL_SERVER_ERROR):
            cls = HTTPClientError
        else:
            cls = HttpError

    return cls(**kwargs)