149 lines
5.2 KiB
Python
149 lines
5.2 KiB
Python
# vim: tabstop=4 shiftwidth=4 softtabstop=4
|
|
|
|
# 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:
|
|
|
|
1) A handy function for getting an object down to something that can be
|
|
JSON serialized. See to_primitive().
|
|
|
|
2) Wrappers around loads() and dumps(). The dumps() wrapper will
|
|
automatically use to_primitive() for you if needed.
|
|
|
|
3) This sets up anyjson to use the loads() and dumps() wrappers if anyjson
|
|
is available.
|
|
'''
|
|
|
|
|
|
import datetime
|
|
import inspect
|
|
import itertools
|
|
import json
|
|
import xmlrpclib
|
|
|
|
from quantum.openstack.common import timeutils
|
|
|
|
|
|
def to_primitive(value, convert_instances=False, level=0):
|
|
"""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.
|
|
|
|
"""
|
|
nasty = [inspect.ismodule, inspect.isclass, inspect.ismethod,
|
|
inspect.isfunction, inspect.isgeneratorfunction,
|
|
inspect.isgenerator, inspect.istraceback, inspect.isframe,
|
|
inspect.iscode, inspect.isbuiltin, inspect.isroutine,
|
|
inspect.isabstract]
|
|
for test in nasty:
|
|
if test(value):
|
|
return unicode(value)
|
|
|
|
# value of itertools.count doesn't get caught by inspects
|
|
# above and results in infinite loop when list(value) is called.
|
|
if type(value) == itertools.count:
|
|
return unicode(value)
|
|
|
|
# FIXME(vish): Workaround for LP bug 852095. Without this workaround,
|
|
# tests that raise an exception in a mocked method that
|
|
# has a @wrap_exception with a notifier will fail. If
|
|
# we up the dependency to 0.5.4 (when it is released) we
|
|
# can remove this workaround.
|
|
if getattr(value, '__module__', None) == 'mox':
|
|
return 'mock'
|
|
|
|
if level > 3:
|
|
return '?'
|
|
|
|
# The try block may not be necessary after the class check above,
|
|
# but just in case ...
|
|
try:
|
|
# 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, (list, tuple)):
|
|
o = []
|
|
for v in value:
|
|
o.append(to_primitive(v, convert_instances=convert_instances,
|
|
level=level))
|
|
return o
|
|
elif isinstance(value, dict):
|
|
o = {}
|
|
for k, v in value.iteritems():
|
|
o[k] = to_primitive(v, convert_instances=convert_instances,
|
|
level=level)
|
|
return o
|
|
elif isinstance(value, datetime.datetime):
|
|
return timeutils.strtime(value)
|
|
elif hasattr(value, 'iteritems'):
|
|
return to_primitive(dict(value.iteritems()),
|
|
convert_instances=convert_instances,
|
|
level=level + 1)
|
|
elif hasattr(value, '__iter__'):
|
|
return to_primitive(list(value),
|
|
convert_instances=convert_instances,
|
|
level=level)
|
|
elif convert_instances and hasattr(value, '__dict__'):
|
|
# Likely an instance of something. Watch for cycles.
|
|
# Ignore class member vars.
|
|
return to_primitive(value.__dict__,
|
|
convert_instances=convert_instances,
|
|
level=level + 1)
|
|
else:
|
|
return value
|
|
except TypeError:
|
|
# Class objects are tricky since they may define something like
|
|
# __iter__ defined but it isn't callable as list().
|
|
return unicode(value)
|
|
|
|
|
|
def dumps(value, default=to_primitive, **kwargs):
|
|
return json.dumps(value, default=default, **kwargs)
|
|
|
|
|
|
def loads(s):
|
|
return json.loads(s)
|
|
|
|
|
|
def load(s):
|
|
return json.load(s)
|
|
|
|
|
|
try:
|
|
import anyjson
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
anyjson._modules.append((__name__, 'dumps', TypeError,
|
|
'loads', ValueError, 'load'))
|
|
anyjson.force_implementation(__name__)
|