Attr-Dict
Yet another Attribute Dict implementation !
This package provides a dictionary with attribute access to keys. It is especially convenient when working with deeply nested data. (Original idea from https://github.com/otsaloma/attd)
Different implementations based on OrderedDict:
-
Strict:
AttrDict
Work as a dictionary with class attribute syntax. Some keys cannot be translated to attributes (like int), in this case revert to usual dict syntax (ie: dict[key]). -
Lazy:
LazyAttrDict
Based on AttrDict but return None on missing keys, and mask values (list of keys on repr()). -
Restricted:
RestrictedAttrDict
Lazy Attribute dictionary enforcing value change from dictionary syntax only (setitem & delitem), and masking values (return list of keys on repr()).Will raise AttributeError on Attribute change (setattr or delattr) to mimic @property attribute.
Basic usage:
# Some dict
>>> conf_A = {'a': 1, 'b': 2, 'c': 3}
>>> conf_B = {'a': 11, 'b': 12, 'c': {'c1': 13, 'c2': 23}}
# import library
>>> from attr_dict import AttrDict, LazyAttrDict, RestrictedAttrDict
## Create a Lazy Attribute Dict
>>> lad = LazyAttrDict()
# Add some data (using different syntax)
>>> lad.A = conf_A
>>> lad['B']= conf_B
# or
>>> lad.update(dict(A=conf_A, B=conf_B))
# Access data
>>> lad
{'A': {'a': 1, 'b': 2, 'c': 3}, 'B': {'a': 11, 'b': 12, 'c': {'c1': 13, 'c2': 23}}}
>>> lad.A
{'a': 1, 'b': 2, 'c': 3}
>>> lad.A.c
3
>>> lad['A']['c']
3
>>> 'c' in lad.A
TrueOther features:
# Export to JSON
>>> json_data = lad.to_json()
>>> print(json_data)
{
"A": {
"a": 1,
"b": 2,
"c": 3
},
"B": {
"a": 11,
"b": 12,
"c": {
"c1": 13,
"c2": 23
}
}
}
## Import JSON to a new Attribute Dict
>>> new_ad = AttrDict().from_json(json_data)
>>> print(new_ad)
AttrDict([('A', AttrDict([('a', 1), ('b', 2), ('c', 3)])), \
('B', AttrDict([('a', 11), ('b', 12), ('c', AttrDict([('c1', 13), ('c2', 23)]))]))])
## Use Restricted Attribute Dict
>>> rad = RestrictedAttrDict()
# Add data using dict syntax (setitem)
>>> rad['A'] = {}
>>> rad['A']['a'] = 1
>>> for k,v in conf_A.items():
... rad['A'][k] = v
...
# Data access to values is restricted
>>> rad
['A']
>>> rad.A
['a', 'b', 'c']
>>> rad.A.b
2
>>> dict(rad.A)
{'a': 1, 'b': 2, 'c': 3}
# Attributes are protected
>>> rad.A = conf_A # doctest: +ELLIPSIS
Traceback (most recent call last):
...
AttributeError: can't set attribute
>>> rad.A.b = 0 # doctest: +ELLIPSIS
Traceback (most recent call last):
...
AttributeError: can't set attribute
>>> del rad.A.b # doctest: +ELLIPSIS
Traceback (most recent call last):
...
AttributeError: can't delete attribute
# Use dict syntax to change or delete
>>> rad.A['b'] = 0
>>> rad.A.pop('b')
0
# Missing key return None
>>> print(rad.A.b)
None
>>> 'b' in rad.A
FalseRelative interfaces named 'indexes' are also available to manage any king of objects with these attribute dictionaries:
AttrIndex, LazyIndex, RestrictedIndex
(current implementation only works on 2 levels)
Index usage:
# Import & init
>>> from attr_dict import LazyIndex
>>> x = LazyIndex()
# set keys & args
>>> x.set_arg('A', a=1, b=2, c=3)
>>> x.set_key('B')
>>> x.index
{'A': {'a': 1, 'b': 2, 'c': 3}, 'B': {}}
# get, del & check
>>> x.get_key('A')
{'a': 1, 'b': 2, 'c': 3}
>>> x.get_arg('A', 'b')
2
>>> x.del_arg('A', 'c')
>>> x.get_key('A')
{'a': 1, 'b': 2}
>>> x.check_arg('A', 'b', 2)
TrueInstall
Install and update using pip:
pip install --upgrade Attr-Dict
Requirements
- Python >= 3.4
- no package dependencies
