How to access JSON child data from file

Question

{
    "event": {
        "firstEventHeader": {
            "domain": "someDomain",
            "eventId": "event001",
            "priority": "Normal",
            "startTimer": timeInMicroSec
        },
        "secondEventHeader": {
            "additionalHeader": [
                {
                    "header": [
                        {
                            "Name": "Name1",
                            "Value": "value1"
                        },
                        {
                            "Name": "Name2",
                            "Value": "value2"
                        },
                        {
                            "Name": "Name3",
                            "Value": "value3"
                        },
                   ],
                    "name": "Field1"
                },

        "thirdEventHeader": {
            "additionalHeader": [
                {
                    "header": [
                        {
                            "Name": "Name4",
                            "Value": "value4"
                        },
                        {
                            "Name": "Name5",
                            "Value": "value5"
                        },
                        {
                            "Name": "Name6",
                            "Value": "value6"
                        },

                    ],
                    "name": "Field2"
                },

I have a file in above format which is getting generated dynamically using a Python script.

I want to access startTimer from firstEventHeader and then name and value from secondEventHeader & thirdEventHeader. Eg.

startTimer : 12345678
    Name1:value1
    Name2:value2
    Name3:value3
    Name4:value4 
    Name5:value5
    Name6:value6

Note: JSON format data is available inside a different file format other than .json. So loading the json will not work as file format is different.

Welcome to SO. This is place where people will help You when You hit a wall, not write code instead of You. — Fejs, Sep 19 '17 at 06:58
https://stackoverflow.com/questions/2835559/parsing-values-from-a-json-file — Siva Guru, Sep 19 '17 at 07:00
@SivaGuru Thanks for welcoming me and for your lovely comments. — newbie, Sep 19 '17 at 08:34

score 0 · Answer 1 · answered Sep 19 '17 at 07:01

You can use the json built-in library. Assuming you can get the json data into some string, this should get you started:

import json

d = json.loads(string)
print(d['event']['firstEventHeader']['startTimer'])

You'll want to do some iteration to get all the Name:Value pairs.

score 0 · Answer 2 · answered Sep 19 '17 at 08:10

If the file is in this format, load it using the json module into a dictionary. You can then traverse that dictionary.

import json
with open('filename') as f:
  data == json.load(f)

e = data['event']
print("Start timer:", e['firstEventHeader']['startTimer'])
def process_header(header_fields):
  for x in header_fields:
    print("Name:", x['Name'], ", Value:", x['Value'])

print("Second event header")
process_header(e['secondEventHeader']['additionalHeader']['header'])

print("Third event header")
process_header(e['thirdEventHeader']['additionalHeader']['header'])

How to access JSON child data from file

2 Answers2