Using a string as a dictionary's index-CodePudding

I have a large dictionary (originally a json), something like this:

dictionary = {
    "Thing1": {
        "Thing1.1": {
            "Thing1.1.1": "Text",
            "Thing1.1.2": "Text",
            "Thing1.1.3": "Text"},
        "Thing1.2": {
            "Thing1.2.1": "Text",
            "Thing1.2.2": "Text",
            "Thing1.2.3": "Text we're interested in"},
        "Thing1.3": {
            "Thing1.3.1": "Text",
            "Thing1.3.2": "Text",
            "Thing1.3.3": "Text"}
    },
    "Thing2": {
            "Thing2.1": {
                "Thing2.1.1": "Text",
                "Thing2.1.2": "Text",
                "Thing2.1.3": "Text"},
            "Thing2.2": {
                "Thing2.2.1": "Text",
                "Thing2.2.2": "Text",
                "Thing2.2.3": "Text"},
            "Thing2.3": {
                "Thing2.3.1": "Text",
                "Thing2.3.2": "Text",
                "Thing2.3.3": "Text"}
        },
    "Thing3": {
        "Thing3.1": {
            "Thing3.1.1": "Text",
            "Thing3.1.2": "Text",
            "Thing3.1.3": "Text"},
        "Thing3.2": {
            "Thing3.2.1": "Text",
            "Thing3.2.2": "Text",
            "Thing3.2.3": "Text"},
        "Thing3.3": {
            "Thing3.3.1": "Text",
            "Thing3.3.2": "Text",
            "Thing3.3.3": "Text"}
    }
}

And, having automated some things, I have some keys that are interesting in a string, as such: key1 = '["Thing1"]["Thing1.2"]["Thing1.2.3"]' and I'd like to be able to call the value for which I have the key as if it was the following: value = dictionary["Thing1"]["Thing1.2"]["Thing1.2.3"]

I have tried using exec, and formatting everything neatly using f-strings, however that's horrible and it does give me some trouble of its own.

CodePudding user response：

If you want to give "1.2.3" and get the item you want from the list you can use this code:

keys = "1.2.3".split(".") 
value = dictionary["Thing"   keys[0]]["Thing"   keys[0]   "."   keys[1]]["Thing"   keys[0]   "."   keys[1]   "."   keys[2]]

If you want, you can get it from your key1 variable:

key1 = '["Thing1"]["Thing1.2"]["Thing1.2.3"]'
keys = key1[key1.rfind("Thing")   5: -2].split(".") 
value = dictionary["Thing"   keys[0]]["Thing"   keys[0]   "."   keys[1]]["Thing"   keys[0]   "."   keys[1]   "."   keys[2]]

CodePudding user response：

As I understand the question, you will always receive the three keys in a string as you showed above, if not please correct me. In that case, I have find the following solution:

text = '["Thing1"]["Thing1.2"]["Thing1.2.3"]'
keys = [eval(i) for i in text.replace("[", "").split("]")[:-1]]
target = dictionary[keys[0]][keys[1]][keys[2]]

Being the variables:

keys = ['Thing1', 'Thing1.2', 'Thing1.2.3']
target = "Text we're interested in"

Edit: You can also do this if you don´t want to use exec or eval:

keys = text.replace("[", "").replace('"', "").split("]")[:-1]
target = dictionary[keys[0]][keys[1]][keys[2]]

If u have a variable depth, you can replace the last lines with:

target = dictionary
for k in keys:
    target = target[k]

CodePudding user response：

Let's assume that the depth of the nested dictionaries is unknown. In that case we need a loop to navigate it. You can use a regular expression to isolate the embedded keys. Something like this:

import re

dictionary = {
    "Thing1": {
        "Thing1.1": {
            "Thing1.1.1": "Text",
            "Thing1.1.2": "Text",
            "Thing1.1.3": "Text"},
        "Thing1.2": {
            "Thing1.2.1": "Text",
            "Thing1.2.2": "Text",
            "Thing1.2.3": "Text we're interested in"},
        "Thing1.3": {
            "Thing1.3.1": "Text",
            "Thing1.3.2": "Text",
            "Thing1.3.3": "Text"}
    },
    "Thing2": {
            "Thing2.1": {
                "Thing2.1.1": "Text",
                "Thing2.1.2": "Text",
                "Thing2.1.3": "Text"},
            "Thing2.2": {
                "Thing2.2.1": "Text",
                "Thing2.2.2": "Text",
                "Thing2.2.3": "Text"},
            "Thing2.3": {
                "Thing2.3.1": "Text",
                "Thing2.3.2": "Text",
                "Thing2.3.3": "Text"}
        },
    "Thing3": {
        "Thing3.1": {
            "Thing3.1.1": "Text",
            "Thing3.1.2": "Text",
            "Thing3.1.3": "Text"},
        "Thing3.2": {
            "Thing3.2.1": "Text",
            "Thing3.2.2": "Text",
            "Thing3.2.3": "Text"},
        "Thing3.3": {
            "Thing3.3.1": "Text",
            "Thing3.3.2": "Text",
            "Thing3.3.3": "Text"}
    }
}

key = '["Thing1"]["Thing1.2"]["Thing1.2.3"]'

list_ = re.findall(r'\"(.*?)\"', key)

d = dictionary

for k in list_:
    if (d := d.get(k)) is None:
        break

print(d)

Output:

Text we're interested in