909c17a779
Now that we only support Python 3 we don't need logic to handle Python 2. Change-Id: I33747d25bc4c67ee13654ed132edf7413371c1dc
271 lines
9.8 KiB
Python
271 lines
9.8 KiB
Python
# Copyright 2010 United States Government as represented by the
|
|
# Administrator of the National Aeronautics and Space Administration.
|
|
# Copyright 2011 Justin Santa Barbara
|
|
# All Rights Reserved.
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License"); you may
|
|
# not use this file except in compliance with the License. You may obtain
|
|
# a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
# License for the specific language governing permissions and limitations
|
|
# under the License.
|
|
|
|
'''
|
|
JSON related utilities.
|
|
|
|
This module provides a few things:
|
|
|
|
#. A handy function for getting an object down to something that can be
|
|
JSON serialized. See :func:`.to_primitive`.
|
|
#. Wrappers around :func:`.loads` and :func:`.dumps`. The :func:`.dumps`
|
|
wrapper will automatically use :func:`.to_primitive` for you if needed.
|
|
#. This sets up ``anyjson`` to use the :func:`.loads` and :func:`.dumps`
|
|
wrappers if ``anyjson`` is available.
|
|
'''
|
|
|
|
|
|
import codecs
|
|
import datetime
|
|
import functools
|
|
import inspect
|
|
import itertools
|
|
import json
|
|
import uuid
|
|
import warnings
|
|
from xmlrpc import client as xmlrpclib
|
|
|
|
from oslo_utils import encodeutils
|
|
from oslo_utils import importutils
|
|
from oslo_utils import timeutils
|
|
|
|
ipaddress = importutils.try_import("ipaddress")
|
|
netaddr = importutils.try_import("netaddr")
|
|
|
|
_nasty_type_tests = [inspect.ismodule, inspect.isclass, inspect.ismethod,
|
|
inspect.isfunction, inspect.isgeneratorfunction,
|
|
inspect.isgenerator, inspect.istraceback, inspect.isframe,
|
|
inspect.iscode, inspect.isbuiltin, inspect.isroutine,
|
|
inspect.isabstract]
|
|
|
|
_simple_types = (str, int, type(None), bool, float)
|
|
|
|
|
|
def to_primitive(value, convert_instances=False, convert_datetime=True,
|
|
level=0, max_depth=3, encoding='utf-8',
|
|
fallback=None):
|
|
"""Convert a complex object into primitives.
|
|
|
|
Handy for JSON serialization. We can optionally handle instances,
|
|
but since this is a recursive function, we could have cyclical
|
|
data structures.
|
|
|
|
To handle cyclical data structures we could track the actual objects
|
|
visited in a set, but not all objects are hashable. Instead we just
|
|
track the depth of the object inspections and don't go too deep.
|
|
|
|
Therefore, ``convert_instances=True`` is lossy ... be aware.
|
|
|
|
If the object cannot be converted to primitive, it is returned unchanged
|
|
if fallback is not set, return fallback(value) otherwise.
|
|
|
|
.. versionchanged:: 2.22
|
|
Added *fallback* parameter.
|
|
|
|
.. versionchanged:: 1.3
|
|
Support UUID encoding.
|
|
|
|
.. versionchanged:: 1.6
|
|
Dictionary keys are now also encoded.
|
|
"""
|
|
orig_fallback = fallback
|
|
if fallback is None:
|
|
fallback = str
|
|
|
|
# handle obvious types first - order of basic types determined by running
|
|
# full tests on nova project, resulting in the following counts:
|
|
# 572754 <type 'NoneType'>
|
|
# 460353 <type 'int'>
|
|
# 379632 <type 'unicode'>
|
|
# 274610 <type 'str'>
|
|
# 199918 <type 'dict'>
|
|
# 114200 <type 'datetime.datetime'>
|
|
# 51817 <type 'bool'>
|
|
# 26164 <type 'list'>
|
|
# 6491 <type 'float'>
|
|
# 283 <type 'tuple'>
|
|
# 19 <type 'long'>
|
|
if isinstance(value, _simple_types):
|
|
return value
|
|
|
|
if isinstance(value, bytes):
|
|
return value.decode(encoding=encoding)
|
|
|
|
# It's not clear why xmlrpclib created their own DateTime type, but
|
|
# for our purposes, make it a datetime type which is explicitly
|
|
# handled
|
|
if isinstance(value, xmlrpclib.DateTime):
|
|
value = datetime.datetime(*tuple(value.timetuple())[:6])
|
|
|
|
if isinstance(value, datetime.datetime):
|
|
if convert_datetime:
|
|
return value.strftime(timeutils.PERFECT_TIME_FORMAT)
|
|
else:
|
|
return value
|
|
|
|
if isinstance(value, uuid.UUID):
|
|
return str(value)
|
|
|
|
if netaddr and isinstance(value, (netaddr.IPAddress, netaddr.IPNetwork)):
|
|
return str(value)
|
|
|
|
if ipaddress and isinstance(value,
|
|
(ipaddress.IPv4Address,
|
|
ipaddress.IPv6Address)):
|
|
return str(value)
|
|
|
|
# For exceptions, return the 'repr' of the exception object
|
|
if isinstance(value, Exception):
|
|
return repr(value)
|
|
|
|
# value of itertools.count doesn't get caught by nasty_type_tests
|
|
# and results in infinite loop when list(value) is called.
|
|
if type(value) == itertools.count:
|
|
return fallback(value)
|
|
|
|
if any(test(value) for test in _nasty_type_tests):
|
|
return fallback(value)
|
|
|
|
if level > max_depth:
|
|
return None
|
|
|
|
# The try block may not be necessary after the class check above,
|
|
# but just in case ...
|
|
try:
|
|
recursive = functools.partial(to_primitive,
|
|
convert_instances=convert_instances,
|
|
convert_datetime=convert_datetime,
|
|
level=level,
|
|
max_depth=max_depth,
|
|
encoding=encoding,
|
|
fallback=orig_fallback)
|
|
if isinstance(value, dict):
|
|
return {recursive(k): recursive(v)
|
|
for k, v in value.items()}
|
|
elif hasattr(value, 'iteritems'):
|
|
return recursive(dict(value.iteritems()), level=level + 1)
|
|
# Python 3 does not have iteritems
|
|
elif hasattr(value, 'items'):
|
|
return recursive(dict(value.items()), level=level + 1)
|
|
elif hasattr(value, '__iter__'):
|
|
return list(map(recursive, value))
|
|
elif convert_instances and hasattr(value, '__dict__'):
|
|
# Likely an instance of something. Watch for cycles.
|
|
# Ignore class member vars.
|
|
return recursive(value.__dict__, level=level + 1)
|
|
except TypeError:
|
|
# Class objects are tricky since they may define something like
|
|
# __iter__ defined but it isn't callable as list().
|
|
return fallback(value)
|
|
|
|
if orig_fallback is not None:
|
|
return orig_fallback(value)
|
|
|
|
# TODO(gcb) raise ValueError in version 3.0
|
|
warnings.warn("Cannot convert %r to primitive, will raise ValueError "
|
|
"instead of warning in version 3.0" % (value,))
|
|
return value
|
|
|
|
|
|
JSONEncoder = json.JSONEncoder
|
|
JSONDecoder = json.JSONDecoder
|
|
|
|
|
|
def dumps(obj, default=to_primitive, **kwargs):
|
|
"""Serialize ``obj`` to a JSON formatted ``str``.
|
|
|
|
:param obj: object to be serialized
|
|
:param default: function that returns a serializable version of an object,
|
|
:func:`to_primitive` is used by default.
|
|
:param kwargs: extra named parameters, please see documentation \
|
|
of `json.dumps <https://docs.python.org/2/library/json.html#basic-usage>`_
|
|
:returns: json formatted string
|
|
|
|
Use dump_as_bytes() to ensure that the result type is ``bytes`` on Python 2
|
|
and Python 3.
|
|
"""
|
|
return json.dumps(obj, default=default, **kwargs)
|
|
|
|
|
|
def dump_as_bytes(obj, default=to_primitive, encoding='utf-8', **kwargs):
|
|
"""Serialize ``obj`` to a JSON formatted ``bytes``.
|
|
|
|
:param obj: object to be serialized
|
|
:param default: function that returns a serializable version of an object,
|
|
:func:`to_primitive` is used by default.
|
|
:param encoding: encoding used to encode the serialized JSON output
|
|
:param kwargs: extra named parameters, please see documentation \
|
|
of `json.dumps <https://docs.python.org/2/library/json.html#basic-usage>`_
|
|
:returns: json formatted string
|
|
|
|
.. versionadded:: 1.10
|
|
"""
|
|
return dumps(obj, default=default, **kwargs).encode(encoding)
|
|
|
|
|
|
def dump(obj, fp, *args, **kwargs):
|
|
"""Serialize ``obj`` as a JSON formatted stream to ``fp``
|
|
|
|
:param obj: object to be serialized
|
|
:param fp: a ``.write()``-supporting file-like object
|
|
:param default: function that returns a serializable version of an object,
|
|
:func:`to_primitive` is used by default.
|
|
:param args: extra arguments, please see documentation \
|
|
of `json.dump <https://docs.python.org/2/library/json.html#basic-usage>`_
|
|
:param kwargs: extra named parameters, please see documentation \
|
|
of `json.dump <https://docs.python.org/2/library/json.html#basic-usage>`_
|
|
|
|
.. versionchanged:: 1.3
|
|
The *default* parameter now uses :func:`to_primitive` by default.
|
|
"""
|
|
default = kwargs.get('default', to_primitive)
|
|
return json.dump(obj, fp, default=default, *args, **kwargs)
|
|
|
|
|
|
def loads(s, encoding='utf-8', **kwargs):
|
|
"""Deserialize ``s`` (a ``str`` or ``unicode`` instance containing a JSON
|
|
|
|
:param s: string to deserialize
|
|
:param encoding: encoding used to interpret the string
|
|
:param kwargs: extra named parameters, please see documentation \
|
|
of `json.loads <https://docs.python.org/2/library/json.html#basic-usage>`_
|
|
:returns: python object
|
|
"""
|
|
return json.loads(encodeutils.safe_decode(s, encoding), **kwargs)
|
|
|
|
|
|
def load(fp, encoding='utf-8', **kwargs):
|
|
"""Deserialize ``fp`` to a Python object.
|
|
|
|
:param fp: a ``.read()`` -supporting file-like object
|
|
:param encoding: encoding used to interpret the string
|
|
:param kwargs: extra named parameters, please see documentation \
|
|
of `json.loads <https://docs.python.org/2/library/json.html#basic-usage>`_
|
|
:returns: python object
|
|
"""
|
|
return json.load(codecs.getreader(encoding)(fp), **kwargs)
|
|
|
|
|
|
try:
|
|
import anyjson
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
anyjson._modules.append((__name__, 'dumps', TypeError,
|
|
'loads', ValueError, 'load'))
|
|
anyjson.force_implementation(__name__)
|