dotstr_key_attrs.py

import re
from functools import reduce

def set_attr(obj, keystr, value, delimiter='.'):
    key_list = keystr.split(delimiter)
    o, k = _set_parse_keystr(obj, key_list)
    o[k] = value
    print('  -+', o[k])
    return obj
    

def _set_parse_keystr(obj, key_list):
    # print('|',key_list)
    key = key_list[0]
    if len(key_list) > 1:
        #print('|0',obj, key_list)
        if obj.get(key) is None:
            obj[key] = {}
        return _set_parse_keystr(obj.get(key), key_list[1:])
    print('|1',obj, key_list)
    if obj.get(key) is None:
        obj[key] = None
    return obj, key

def get_attr(obj, keystr, delimiter='.'):
    key_list = keystr.split(delimiter)
    a = reduce(lambda el, key: _get_parse_keystr(el, key), key_list, obj)
    print('  ->', a)
    return a

def _get_parse_keystr(obj, keystr):
    if re.search(r'(.*)\[\d?\]$', keystr):
        key, index, _ = re.split('\[|\]', keystr)
        return obj.get(key)[int(index)]
    else:
        return obj.get(keystr)


if __name__ == '__main__':
    o = {
            'a': {
                'bb': {
                    'ccc': 123
                },
                'bb2': 14,
                'bb3': {
                    'b3c1': '@b3c1',
                    'b3c2': '@b3c2',
                }
            },
            'aa': [1,2,3,4,5],
            'aad': [
                {'aad0':None},
                {'aad1-1':'*1-1'},
                {'aad2-1':'*2-1','aad2-2':'*2-2'},
                {'aad3-1':'*3-1'}
            ]
        }
    print(o)
    get_attr(o, 'a.bb.ccc')
    get_attr(o, 'a.bb2')
    get_attr(o, 'a.bb3')
    set_attr(o, 'a.bb3.b3c1', '@@@')
    set_attr(o, 'a.b0.j.k.l', '#0jkl')
    get_attr(o, 'aa[2]')
    get_attr(o, 'aad[1].aad1-1')
    get_attr(o, 'aad[2].aad2-2')
    print(o)