Python - Writing JSON data to file

Question

I have a Python function that generates a JSON output. I am trying to see how could I write this to a file.

{'logs': ['3982f208'], 'events': [{'sequence_number': 06972977357, 'labels': [], 'timestamp': 1556539666498, 'message': 'abc [2015-12-19 12:07:38.966] INFO [b5e04d2f5948] [ProcessController] PRMS: {"MessageType"=>"TYPE1", "Content"=>{"Name"=>"name1", "Country"=>"europe", "ID"=>"345", "Key1"=>"634229"}}}

I tried the below:

def output():   <-- This function returns the above JSON data
    json_data()

I tried to write it but creating a new function as below:

def write():
    f = open('results.txt', 'a'). <<- Creates the text file
    f.write(json_data)
    f.close()

This only creates an empty file. Could anyone advice as to how could I write the JSON data to the file.

That is not JSON, you will have to use [`json.dump()`](https://docs.python.org/3/library/json.html#basic-usage). — Klaus D., May 09 '19 at 11:53
@OlvinRoght, I tried to write the output from the earlier function (`def output()`)to the `def write` function — scott martin, May 09 '19 at 11:54
I am pretty sure your output function doesn't return anything. You can double check by checking what `f.write()` returns. It should return the amount of bytes written. My guess is that in your case it'll be 0 — Thomas Bartelmess, May 09 '19 at 11:56
@ThomasBartelmess He's never calling the `output()` function. — Barmar, May 09 '19 at 11:56
@ThomasBartelmess I am successfully able to return back the JSON data using `output` func.I am now trying to have this written to a file — scott martin, May 09 '19 at 11:57

score 0 · Answer 1 · answered May 09 '19 at 11:59

0

The output() function isn't returning anything, it needs a return statement:

def output():
    return json_data():

The write() function needs to call the output() function.

def write():
    with open("results.txt", "a") as f:
        f.write(output())

answered May 09 '19 at 11:59

Barmar

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score 0 · Answer 2 · answered May 09 '19 at 12:02

If you want to use the json package I think this works:

import json
json_src = """{'logs': ['3982f208'], 'events': [{'sequence_number': 06972977357, 'labels': [], 'timestamp': 1556539666498, 'message': 'abc [2015-12-19 12:07:38.966] INFO [b5e04d2f5948] [ProcessController] PRMS: {"MessageType"=>"TYPE1", "Content"=>{"Name"=>"name1", "Country"=>"europe", "ID"=>"345", "Key1"=>"634229"}}}"""

# Can be wrapped in your write() function if you so choose
with open("results.txt", "a") as file:
  json.dump(json_src, file)

could you please assist in figuring how could I store the JSON output to a variable in `def output ()` — scott martin, May 09 '19 at 12:06

Python - Writing JSON data to file

2 Answers2