How to find all the occurrence of a key in nested dict and move the value of that key outside of that key, while deleting all the other keys

Question

a={
    "a": "1",
    "b": "2",
    "c": "3",
    "properties": {
        "test1": "1",
        "test2": "2",
        "test3": {
            "a1": "70",
            "a2": "71",
            "a3": {
                "b1": "80",
                "b2": "81",
                "properties": {
                    "b1": "20",
                    "b2": "21",
                },
                "d1": "30",
                "d2": "31",
            },
        },
    },
}

i want "a" to just have all the keys and value inside of "properties" key.

final_a = {
        "test1": "1",
        "test2": "2",
        "test3": {
            "a1": "70",
            "a2": "71",
            "a3": {
                "b1": "20",
                "b2": "21",
                  },
            },
        }

I have tried all the solution on Find all occurrences of a key in nested dictionaries and lists

do you mean like `a = a['properties']`? – rv.kvetch May 17 '22 at 14:18 — rv.kvetch, May 17 '22 at 14:18
yes, but also for all the "properties" in the code block. – yadavender yadav May 17 '22 at 14:23 — yadavender yadav, May 17 '22 at 14:23
the output is not a valid dictionary – mozway May 17 '22 at 14:24 — mozway, May 17 '22 at 14:24

score 3 · Answer 1 · answered May 17 '22 at 14:31

IIUC, you can use a recursive function. If properties is a key, replace the current iteration with it else return the dictionary applying the function on the dictionary values:

def nested_prop(d):
    if 'properties' in d:
        return nested_prop(d['properties'])
    return {k:nested_prop(v) if isinstance(v, dict) else v
            for k,v in d.items()}

nested_prop(a)

output:

{'test1': '1',
 'test2': '2',
 'test3': {'a1': '70', 'a2': '71', 'a3': {'b1': '20', 'b2': '21'}}}

score 1 · Answer 2 · answered May 17 '22 at 14:30

You could use a recursive update function to traverse through a dict and search for any properties key, as shown below:

from pprint import pprint

a = {
    "a": "1",
    "b": "2",
    "c": "3",
    "properties": {
        "test1": "1",
        "test2": "2",
        "test3": {
            "a1": "70",
            "a2": "71",
            "a3": {
                "b1": "80",
                "b2": "81",
                "properties": {
                    "b1": "20",
                    "b2": "21",
                },
                "d1": "30",
                "d2": "31",
            },
        },
    },
}


def recursive_update(d: dict) -> dict:
    if 'properties' in d:
        d = d['properties']

    for k, v in d.items():
        if isinstance(v, dict):
            d[k] = recursive_update(v)
        elif isinstance(v, list):
            d[k] = [recursive_update(e) if isinstance(e, dict) else e for e in v]

    return d


print('Before:')
print(a)
# {'a': '1', 'b': '2', 'c': '3', 'properties': {'test1': '1', 'test2': '2', 'test3': {'a1': '70', 'a2': '71', 'a3': {'b1': '80', 'b2': '81', 'properties': {'b1': '20', 'b2': '21'}, 'd1': '30', 'd2': '31'}}}}

a = recursive_update(a)

print('After:')
pprint(a)

Result:

Before:
{'a': '1', 'b': '2', 'c': '3', 'properties': {'test1': '1', 'test2': '2', 'test3': {'a1': '70', 'a2': '71', 'a3': {'b1': '80', 'b2': '81', 'properties': {'b1': '20', 'b2': '21'}, 'd1': '30', 'd2': '31'}}}}
After:
{'test1': '1',
 'test2': '2',
 'test3': {'a1': '70', 'a2': '71', 'a3': {'b1': '20', 'b2': '21'}}}

How to find all the occurrence of a key in nested dict and move the value of that key outside of that key, while deleting all the other keys

2 Answers2