How can I keep the first key in the JSON without replacing the new one?-CodePudding

Main.py

import json

def test(key, value):
    with open("test.json", "r", encoding="utf-8") as f:
        x = json.load(f)

        num = 1

        try:
            if f"q{num}" in x["keys"]: # Checking if index 1 is exist
                for _ in range(num):
                    num  = 1
        except:
            pass

        x["keys"] = {}
        x["keys"][f"{num}"] = {"key": key, "value": value} # Dict for json file
        
        with open("test.json", "w", encoding="utf-8") as f:
            json.dump(x, f, indent=4, ensure_ascii=False) # Write the json file


test("test", "testvalue")
test("test2", "testvalue2")

test.json

{
    "keys": {
        "1": {
            "key": "test2",
            "value": "testvalue2"
        }
    }
}

How can I keep the first question without replacing the second one? I wanted to make it like this (If it possible):

{
    "keys": {
        "1": {
            "key": "test",
            "value": "testvalue"
        },

        "2": {
            "key": "test2",
            "value": "testvalue2"
        }
    }
}

I'm not sure if its really possible to make it like this. If its not possible to do this, please let me know!

CodePudding user response：

You could try something like this. It checks whether you can actually load the file as json (since that will fail with an empty file), then finds the maximum key value in the keys dict and adds a new entry with an incremented key.

import json

def test(key, value):
    with open("test.json", "r", encoding="utf-8") as f:
        try:
            x = json.load(f)
            next_key = max(map(int, x['keys'].keys()))   1
        except:
            # empty file
            x = { 'keys' : {} }
            next_key = 1
    
    # add the new value
    x['keys'].update({ next_key : { 'key' : key, 'value' : value } })
    
    # write the new data
    with open("test.json", "w", encoding="utf-8") as f:
        json.dump(x, f, indent=4, ensure_ascii=False)

Contents of test.json after running:

test("test", "testvalue")
test("test2", "testvalue2")

will be:

{
    "keys": {
        "1": {
            "key": "test",
            "value": "testvalue"
        },
        "2": {
            "key": "test2",
            "value": "testvalue2"
        }
    }
}