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How to delete an element in a json file python

I am trying to delete an element in a json file,
here is my json file:
before:
{
"names": [
{
"PrevStreak": false,
"Streak": 0,
"name": "Brody B#3719",
"points": 0
},
{
"PrevStreak": false,
"Streak": 0,
"name": "XY_MAGIC#1111",
"points": 0
}
]
}
after running script:
{
"names": [
{
"PrevStreak": false,
"Streak": 0,
"name": "Brody B#3719",
"points": 0
}
]
}
how would I do this in python? the file is stored locally and I am deciding which element to delete by the name in each element
Thanks

I would load the file, remove the item, and then save it again. Example:
import json
with open("filename.json") as f:
data = json.load(f)
f.pop(data["names"][1]) # or iterate through entries to find matching name
with open("filename.json", "w") as f:
json.dump(data, f)

You will have to read the file, convert it to python native data type (e.g. dictionary), then delete the element and save the file. In your case something like this could work:
import json
filepath = 'data.json'
with open(filepath, 'r') as fp:
data = json.load(fp)
del data['names'][1]
with open(filepath, 'w') as fp:
json.dump(data, fp)

Try this:
# importing the module
import ast
# reading the data from the file
with open('dictionary.txt') as f:
data = f.read()
print("Data type before reconstruction : ", type(data))
# reconstructing the data as a dictionary
a_dict = ast.literal_eval(data)
{"names":[a for a in a_dict["names"] if a.get("name") !="XY_MAGIC#1111"]}

import json
with open("test.json",'r') as f:
data = json.loads(f.read())
names=data.get('names')
for idx,name in enumerate(names):
if name['name']=='XY_MAGIC#1111':
del names[idx]
break
print(names)
In order to read the file best approach would be using the with statement after which you could just use pythons json library and convert json string to python dict. once you get dict you can access the values and do your operations as required. you could convert it as json using json.dumps() then save it

This does the right thing useing the python json module, and prettyprints the json back to the file afterwards:
import json
jsonpath = '/path/to/json/file.json'
with open(jsonpath) as file:
j = json.loads(file.read())
names_to_remove = ['XY_MAGIC#1111']
for element in j['names']:
if element['name'] in names_to_remove:
j['names'].remove(element)
with open(jsonpath, 'w') as file:
file.write(json.dumps(j, indent=4))

Getting value from a JSON file based on condition

In python I'm trying to get the value(s) of the key "relativePaths" from a JSON element if that element contains the value "concept" for the key "tags". The JSON file has the following format.
]
},
{
"fileName": "#Weizman.2011",
"relativePath": "Text/#Weizman.2011.md",
"tags": [
"text",
"concept"
],
"frontmatter": {
"authors": "Weizman",
"year": 2011,
"position": {
"start": {
"line": 0,
"col": 0,
"offset": 0
},
"end": {
"line": 4,
"col": 3,
"offset": 120
}
}
},
"aliases": [
"The least of all possible evils - humanitarian violence from Arendt to Gaza"
],
I have tried the following codes:
import json
with open("/Users/metadata.json") as jsonFile:
data = json.load(jsonFile)
for s in range(len(data)):
if 'tags' in s in range(len(data)):
if data[s]["tags"] == "concept":
files = data[s]["relativePaths"]
print(files)
Which results in the error message:
TypeError: argument of type 'int' is not iterable
I then tried:
with open("/Users/metadata.json") as jsonFile:
data = json.load(jsonFile)
for s in str(data):
if 'tags' in s in str(data):
print(s["relativePaths"])
That code seems to work. But I don't get any output from the print command. What am I doing wrong?

Assuming your json is a list of the type you put on your question, you can get those values like this:
with open("/Users/metadata.json") as jsonFile:
data = json.load(jsonFile)
for item in data: # Assumes the first level of the json is a list
if ('tags' in item) and ('concept' in item['tags']): # Assumes that not all items have a 'tags' entry
print(item['relativePaths']) # Will trigger an error if relativePaths is not in the dictionary

Figured it
import json
f = open("/Users/metadata.json")
# returns JSON object as
# a dictionary
data = json.load(f)
# Iterating through the json
# list
for i in data:
if "tags" in i:
if "concept" in i["tags"]:
print(i["relativePaths"])
# Closing file
f.close()

I think this will do what you want. It is more "pythonic" because it doesn't use numerical indices to access elements of the list — making it easier to write and read).
import json
with open("metadata.json") as jsonFile:
data = json.load(jsonFile)
for elem in data:
if 'tags' in elem and 'concept' in elem['tags']:
files = elem["relativePath"]
print(files)

Extract certain information from json into csv

I have a json file that look like this:
{
"issueInfo" : [ {
"cid" : 494960,
"occurrences" : [ {
"file" : "/components/applications/diag/_common/src/diag_il.c",
"function" : "diag_il_u8StopLoopbackMicIn",
"mainEventLineNumber" : 6018,
"mainEventDescription" : "Assigning value \"10\" to \"u8ResData\" here, but that stored value is overwritten before it can be used.",
} ],
"triage" : {
"classification" : "Unclassified"
},
}
I want to extract out the information like cid, firstDetectedDateTime, file, function, mainEventLineNumber, mainEventDescription and classification. All of these information needed will be put into a csv file. The following is my coding:
import csv
import json
with open ("a.log","r") as file:
data=json.load(file)
f=csv.writer(open("test.csv", "w", newline=''))
f.writerow(["cid", "firstDetectedDateTime", "file", "function",
"mainEventLineNumber", "mainEventDescription", "classification"])
for data in file:
f.writerow(data["issueInfo"]["cid"],
data["issueInfo"]["firstDetectedDateTime"],
data["issueInfo"]["occurrences"]["file"],
data["issueInfo"]["occurrences"]["function"],
data["issueInfo"]["occurrences"]["mainEventLineNumber"],
data["issueInfo"]["occurrences"]["mainEventDescription"],
data["issueInfo"]["triage"]["classification"])
The error shown after I run the command is :
TypeError: string indices must be integers
Anyone can help me to solve this problem? Thanks

Check the type of data (It must be a dictionary). Also, there is an invalid key error firstDetectedDateTime.
Try this,
import csv
import json
with open ("a.log","r") as file:
data=json.load(file)
f=csv.writer(open("test.csv", "w", newline=''))
f.writerow(["cid", "firstDetectedDateTime", "file", "function","mainEventLineNumber","mainEventDescription", "classification"])
f.writerow([data["issueInfo"][0]["cid"],
"",
data["issueInfo"][0]["occurrences"][0]["file"],
data["issueInfo"][0]["occurrences"][0]["function"],
data["issueInfo"][0]["occurrences"][0]["mainEventLineNumber"],
data["issueInfo"][0]["occurrences"][0]["mainEventDescription"],
data["issueInfo"][0]["triage"]["classification"]])
Output CSV looks like,
cid,firstDetectedDateTime,file,function,mainEventLineNumber,mainEventDescription,classification
494960,,/components/applications/diag/_common/src/diag_il.c,diag_il_u8StopLoopbackMicIn,6018,"Assigning value ""10"" to ""u8ResData"" here, but that stored value is overwritten before it can be used.",Unclassified
If the page contains many JSON sets eg:data_sets here, Keep the headers fixed only change the portion below that.
for data in data_sets:
f.writerow([data["issueInfo"][0]["cid"],
"",
data["issueInfo"][0]["occurrences"][0]["file"],
data["issueInfo"][0]["occurrences"][0]["function"],
data["issueInfo"][0]["occurrences"][0]["mainEventLineNumber"],
data["issueInfo"][0]["occurrences"][0]["mainEventDescription"],
data["issueInfo"][0]["triage"]["classification"]])

The json library in python can parse JSON from strings or files. The library parses JSON into a Python dictionary or list
json.loads() function parses the json string data and it can be used as a normal dictionary in python. And we can access the values using keys.
import json
import csv
employee_data = '{"employee_details":[{"employee_name": "James", "email": "james#gmail.com", "job_profile": "Sr. Developer"},{"employee_name": "Smith", "email": "Smith#gmail.com", "job_profile": "Project Lead"}]}'
employee_parsed = json.loads(employee_data)
emp_data = employee_parsed['employee_details']
# open a file for writing
employ_data = open('..../EmployData.csv', 'w')
# create the csv writer object
csvwriter = csv.writer(employ_data)
count = 0
for emp in emp_data:
if count == 0:
header = emp.keys()
csvwriter.writerow(header)
count += 1
csvwriter.writerow(emp.values())
employ_data.close()

How can I use jsonpath in python to change an element value in the json object

I have the following json object (Say car_details.json):
{
"name":"John",
"age":30,
"cars":
[
{
"car_model": "Mustang",
"car_brand": "Ford"
},
{
"car_model": "cx-5",
"car_brand": "Mazda"
}
}
I want to change the value of car_model from cx-5 to cx-9 through python code.
I am providing the json path to this element, through an external file. The json-path expression is basically represented as a string. Something like this:
'cars[2].car_model'
And the new value is also provided through an external file as a string:
'cx-9'
Now how do I parse through car_details.json using the jsonpath expression, and change its value to the one provided as string, and finally return the modified json object
P.S I want to do this through python code

This is an approach without using json module. Load your data in variable. Then iterate over cars key/values. If you find the key that is the value you are looking for set it to new value.
Also note: you need to close your array block, otherwise your above json is not valid. Generally I use an online json parser to check if my data is valid etc. (may be helpful in future).
data = {
"name":"John",
"age":30,
"cars":
[
{
"car_model": "Mustang",
"car_brand": "Ford"
},
{
"car_model": "cx-5",
"car_brand": "Mazda"
}
]
}
for cars in data['cars']:
for key, value in cars.items():
if key == "car_model" and value == "cx-5":
cars[key] = "cx-9"
print(data)
If you want to load your json object from a file, let's assume it is called "data.json" and is in the same directory as the python script you are going to run:
import json
with open('data.json') as json_data:
data = json.load(json_data)
for cars in data['cars']:
for key, value in cars.items():
if key == "car_model" and value == "cx-5":
cars[key] = "cx-9"
print(data)
Now if you'd like to write the content to the original file or new file, in this case I am writing to a file called "newdata.json":
import json
import re
with open('data.json') as json_data:
data = json.load(json_data)
print(data)
with open('external.txt') as f:
content = f.read()
print(content)
for cars in data['cars']:
for key, value in cars.items():
if key == "car_model" and value == "cx-5":
cars[key] = content
with open('newdata.json', 'w') as outfile:
json.dump(data, outfile)

How to read an ascii file with json content: ValueError

I try to read this ascii file with this json content with the following function:
{ "directory": { "name": "/wiki", "files": { "file": [ { "name": "/wiki/a.txt", "digest": "97d37a2ff85fbe35e1bf8ad38934d8fb518a6a3fbeb9b0b9305ce98e992f9dd2 " },
{ "name": "/wiki/d.txt", "digest": "ef91ee1257c3faa49f86f343cfec66010e5810e99db9f42e88774f90cd5b95d9 " },] } } }
def readJsonFile(path):
with open(path) as json_file:
json_data = json.load(json_file)
return json_data
I get this error of no JSON object could be decoded:
ValueError: No JSON object could be decoded
I tried with json.loads and I get the error:
TypeError: expected string or buffer
Am I using the right function?

The data is not a valid json (It has a trailing ,).
But it's a valid python literal; you can use ast.literal_eval instead:
import ast
def readJsonFile(path):
with open(path) as json_file:
return ast.literal_eval(json_file.read())

Your json string is wrong, as validated by jsonint: