I have a list which contains the route to a node in the json. How do access the node based on this route?

Question

I have a list which contains data in the following format.

Data format: "1.3.4.2.1", "1.45.67.32.2", ...(the strings separated by dots 
can be of varying lengths)

This strings represent the route to the "status" node and the "last index" in the string represent the value that has to be assigned to the "@default" attribute in the status node.

I have a json of the following format.

json_tree = 
{
  "Gardens": {
    "Seaside": {
      "@loc": "porch",
      "@myID": "1.2.3",
      "Tid": "1",
      "InfoList": {
        "status": {
          "@default": "0",
          "@myID": "26"
        },
        "count": {
          "@default": "0",
          "@myID": "1"
        }
      },
      "BackYard": {
        "@loc": "backyard",
        "@myID": "75",
        "Tid": "2",
        "InfoList": {
          "status": {
            "@default": "6",
            "@myID": "32"
          },
          "count": {
            "@default": "0",
            "@myID": "2"
          }
        }
      }
    }
  }
}

In this case, my route list contains the following information.

route_list = ["1.2.3.26.4","1.2.3.75.32.2",...] # this json_tree could have many more layers in the format shown above

Note: '1.2.3.26" is the route to the "status" node in "Gardens" and "4" is the value to be assigned to the "@default" node in the "status".
Note: '1.2.3.75.32" is the route to the "status" node in "BackYard" and "2" is the value to be assigned to the "@default" node in the "status".

As of now, I have the following method. I am unable to move further from here.

for item in route_list:
   UpdateJsonTree(json_tree, item)

def UdpateJsonTree(json_tree, item):
   # I am unsure on how to parse the json tree based on the route given
   # and update the '@default' value of the status node 

Any help would be appreciated. Thanks.

Answer 1

This approach starts by building a route master that includes a list entry for each route to check against (displayed at bottom).

Once the route master is available then the route check is straight forward.

flatten is from the 179 point answer here

Please let me know if you need any clarification.

Here's the code:

import _collections_abc
import itertools
from pprint import pprint

l1 = [
    '1.2.3.26.4',
    '1.2.3.75.32.2'
]

json_tree = {
    "Gardens": {
        "Seaside": {
            "@loc": "porch",
            "@myID": "1.2.3",
            "Tid": "1",
            "InfoList": {
                "status": {
                    "@default": "0",
                    "@myID": "26"
                },
                "count": {
                    "@default": "0",
                    "@myID": "1"
                }
            },
            "BackYard": {
                "@loc": "backyard",
                "@myID": "75",
                "Tid": "2",
                "InfoList": {
                    "status": {
                        "@default": "6",
                        "@myID": "32"
                    },
                    "count": {
                        "@default": "0",
                        "@myID": "2"
                    }
                }
            }
        }
    }
}


def flatten(d, parent_key='', sep='_'):
    """Return flattened dict as list"""
    items = []
    for k, v in d.items():
        new_key = parent_key + sep + k if parent_key else k
        if isinstance(v, _collections_abc.MutableMapping):
            items.extend(flatten(v, new_key, sep=sep).items())
        else:
            items.append((new_key, v))
    return dict(items)


def add_id(path, id_value):
    """Update list of @myID paths"""
    id_list.append([path, id_value])


def update_json(path, value):
    """Update the json_data with the default value"""
    l_bracket_q = "['"
    r_bracket_q = "']"
    at_default = "['@default']"
    result = ''
    cmd = "json_tree"
    for key in path:
        cmd += l_bracket_q + key + r_bracket_q
    cmd += at_default
    cmd += ' = value'
    exec(cmd)


flat_list = flatten(json_tree)
id_list = []

#  Loop the flattened list filtering for ID's, excluding the ones in count
for k, v in [x for x in flat_list.items() if '@myID' in x[0] and 'count' not in x[0]]:
    add_id(k, v)

route_list = []

# start building the route list from the filtered id list
for id_entry in id_list:
    route_list.append(
        [[x for x in id_entry[0].split('_') if x != '@myID'],
         [y for y in id_entry[1].split('.')]])

route_master = []

#  generate the route master to include the path and the full route (as list not 1.2.3)
for id_entry in id_list:
    s1 = id_entry[0].split('_')
    tmp_route = []
    tmp_list = []
    for i in range(len(s1)):
        if s1[i] == '@myID':
            break
        tmp_list.append(s1[i])
        for rte in route_list:
            if tmp_list == rte[0]:
                tmp_route.append(rte[1])
    route_item = list(itertools.chain(*tmp_route))
    tmp_list.append(route_item)
    route_master.append(tmp_list)

#  break out the default value from the route of the main driver file
l2 = list(zip(['.'.join(x.split('.')[:-1]) for x in l1], [x.split('.')[-1] for x in l1]))

#  loop the routes to process and update when found
for route, default in l2:
    for check_it in route_master:
        if route.split('.') == check_it[-1]:
            update_json(check_it[:-1], default)

#  print results
pprint(json_tree)

results:

{'Gardens': {'Seaside': {'@loc': 'porch',
                         '@myID': '1.2.3',
                         'BackYard': {'@loc': 'backyard',
                                      '@myID': '75',
                                      'InfoList': {'count': {'@default': '0',
                                                             '@myID': '2'},
                                                   'status': {'@default': '2',
                                                              '@myID': '32'}},
                                      'Tid': '2'},
                         'InfoList': {'count': {'@default': '0', '@myID': '1'},
                                      'status': {'@default': '4',
                                                 '@myID': '26'}},
                         'Tid': '1'}}}

Route Master:

['Gardens', 'Seaside', ['1', '2', '3']]
['Gardens', 'Seaside', 'InfoList', 'status', ['1', '2', '3', '26']]
['Gardens', 'Seaside', 'BackYard', ['1', '2', '3', '75']]
['Gardens', 'Seaside', 'BackYard', 'InfoList', 'status', ['1', '2', '3', '75', '32']]