Source code for flask_restx.utils

# -*- coding: utf-8 -*-
from __future__ import unicode_literals

import re

from collections import OrderedDict
from copy import deepcopy
from six import iteritems

from ._http import HTTPStatus


FIRST_CAP_RE = re.compile("(.)([A-Z][a-z]+)")
ALL_CAP_RE = re.compile("([a-z0-9])([A-Z])")


__all__ = (
    "merge",
    "camel_to_dash",
    "default_id",
    "not_none",
    "not_none_sorted",
    "unpack",
)


[docs]def merge(first, second): """ Recursively merges two dictionaries. Second dictionary values will take precedence over those from the first one. Nested dictionaries are merged too. :param dict first: The first dictionary :param dict second: The second dictionary :return: the resulting merged dictionary :rtype: dict """ if not isinstance(second, dict): return second result = deepcopy(first) for key, value in iteritems(second): if key in result and isinstance(result[key], dict): result[key] = merge(result[key], value) else: result[key] = deepcopy(value) return result
[docs]def camel_to_dash(value): """ Transform a CamelCase string into a low_dashed one :param str value: a CamelCase string to transform :return: the low_dashed string :rtype: str """ first_cap = FIRST_CAP_RE.sub(r"\1_\2", value) return ALL_CAP_RE.sub(r"\1_\2", first_cap).lower()
[docs]def default_id(resource, method): """Default operation ID generator""" return "{0}_{1}".format(method, camel_to_dash(resource))
[docs]def not_none(data): """ Remove all keys where value is None :param dict data: A dictionary with potentially some values set to None :return: The same dictionary without the keys with values to ``None`` :rtype: dict """ return dict((k, v) for k, v in iteritems(data) if v is not None)
[docs]def not_none_sorted(data): """ Remove all keys where value is None :param OrderedDict data: A dictionary with potentially some values set to None :return: The same dictionary without the keys with values to ``None`` :rtype: OrderedDict """ return OrderedDict((k, v) for k, v in sorted(iteritems(data)) if v is not None)
[docs]def unpack(response, default_code=HTTPStatus.OK): """ Unpack a Flask standard response. Flask response can be: - a single value - a 2-tuple ``(value, code)`` - a 3-tuple ``(value, code, headers)`` .. warning:: When using this function, you must ensure that the tuple is not the response data. To do so, prefer returning list instead of tuple for listings. :param response: A Flask style response :param int default_code: The HTTP code to use as default if none is provided :return: a 3-tuple ``(data, code, headers)`` :rtype: tuple :raise ValueError: if the response does not have one of the expected format """ if not isinstance(response, tuple): # data only return response, default_code, {} elif len(response) == 1: # data only as tuple return response[0], default_code, {} elif len(response) == 2: # data and code data, code = response return data, code, {} elif len(response) == 3: # data, code and headers data, code, headers = response return data, code or default_code, headers else: raise ValueError("Too many response values")