Question 109864 in Json Question posted in
Our archive of expertly curated questions and answers provides insights and solutions to common problems related to this popular data interchange format. From parsing and manipulating JSON data to integrating it with various programming languages and web services, our archive has got you covered. Start exploring today and take your JSON skills to the next level

Append to a json file using python

Trying to append to a nested json file

My goal is to append some values to a JSON file.

Here is my original JSON file

{
    "web": {
        "all": {
          "side": {
            "tags": [
              "admin"
            ],
            "summary": "Generates",
            "operationId": "Key",
            "consumes": [],
            "produces": [
              "application/json"
            ],
            "responses": {
              "200": {
                "description": "YES",
                "schema": {
                  "type": "string"
                }
              }
            },
            "Honor": [
              {
                "presidential": []
              }
            ]
          }
        }

    }
}

It is my intention to add two additional lines inside the key "Honor", with the values "Required" : "YES" and "Prepay" : "NO". As a result of appending the two values, I will have the following JSON file.

{
    "web": {
        "all": {
          "side": {
            "tags": [
              "admin"
            ],
            "summary": "Generates",
            "operationId": "Key",
            "consumes": [],
            "produces": [
              "application/json"
            ],
            "responses": {
              "200": {
                "description": "YES",
                "schema": {
                  "type": "string"
                }
              }
            },
            "Honor": [
              {
                "presidential": [],
                "Required" : "YES",
                "Prepay"   : "NO"
              }
            ]
          }
        }

    }
}

Below is the Python code that I have written

import json
def write_json(data,filename ="exmpleData.json"):
    with open(filename,"w") as f:
        json.dump(data,f,indent=2)
with open ("exmpleData.json") as json_files:
    data= json.load(json_files)
    temp = data["Honor"]
    y = {"required": "YES","type": "String"}
    temp.append(y)
write_json(data)

I am receiving the following error message:

** temp = data["Honor"] KeyError: ‘Honor’
**
I would appreciate any guidance that you can provide to help me achieve my goal. I am running Python 3.7

Tags:

2

Answers


  1. 0

    'Honor' is deeply nested in other dictionaries, and its value is a 1-element list containing a dictionary. Here’s how to access:

    import json

def write_json(data, filename='exmpleData.json'):
    with open(filename, 'w') as f:
        json.dump(data, f, indent=2)

with open('exmpleData.json') as json_files:
    data = json.load(json_files)
    # 'Honor' is deeply nested in other dictionaries
    honor = data['web']['all']['side']['Honor']
    # Its value is a 1-element list containing another dictionary.
    honor[0]['Required'] = 'YES'
    honor[0]['Prepay'] = 'NO'

write_json(data)
    Login or Signup to reply.
  2. 0

    I’d recommend that you practice your fundamentals a bit more since you’re making many mistakes in your data structure handling. The good news is, your JSON load/dump is fine.

    The cause of your error message is that data doesn’t have an "Honor" property. Data only has a "web" property, which contains "all" which contains "side" which contains "Honor", which contains an array with a dictionary that holds the properties you are trying to add to. So you want to set temp with temp = data['web']['all']['side']['Honor'][0]

    You also cannot use append on python dictionaries. Instead, check out dict.update().

    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search