Reading a Json in python

Question

I need to get a particular key:value from a json file.

Code used to open json file :

import json
data = repr(open('file.json', 'rb').read())
print(data)

Output( Json file) :

b'b\'{"image":{"width":750,"height":1127,"orientation":1},"objects":[{"type":"face","boundingBox":{"x":132,"y":180,"height":619,"width":513},"landmarks":{"faceContour":[[162,375],[162,440],[165,504],[175,568],[193,628],[226,686],[265,740],[313,784],[373,799],[436,793],[494,758],[543,712],[586,660],[616,601],[631,534],[639,468],[645,400]],"noseBridge":[[387,396],[385,441],[381,485],[378,532]],"noseBall":[[322,547],[350,560],[380,572],[412,563],[442,554]],"eyebrowRight":[[419,348],[466,329],[516,325],[564,339],[595,377]],"eyebrowLeft":[[197,358],[224,325],[269,315],[316,325],[358,347]],"eyeRight":[[448,419],[479,404],[510,405],[539,416],[511,425],[480,424]],"eyeRightCenter":[[495,416]],"eyeLeft":[[242,402],[269,393],[299,396],[329,412],[297,414],[267,413]],"eyeLeftCenter":[[284,405]],"mouthOuter":[[269,596],[310,598],[349,598],[379,606],[411,601],[456,606],[502,609],[456,663],[412,684],[378,687],[345,680],[307,652]],"mouthInner":[[284,603],[349,610],[379,615],[411,613],[487,614],[412,652],[379,656],[348,648]]},"attributes":{"gender":"male","genderConfidence":0.8385,"age":24,"ageConfidence":0.8419,"emotion":"happiness","emotionConfidence":1.0,"emotionsAll":{"neutral":0.0,"sadness":0.0,"disgust":0.0,"anger":0.0,"surprise":0.0,"fear":0.0,"happiness":1.0},"pose":{"pitch":-5.7105,"roll":0.2941,"yaw":1.8646},"race":{"asian":0.0002,"black":0.0001,"white":0.9989},"eyewear":{"sunglasses":0.0,"glasses":0.0},"hair":{"color":{"blond":0.0,"black":0.9994,"brown":0.0},"cut":{"short":0.9999,"long":0.0,"bald":0.0},"facial":{"beard":0.0,"mustache":0.0,"stubble":0.2543}},"frontal":true}},{"type":"person","boundingBox":{"x":20,"y":60,"height":1053,"width":696}}],"requestId":"1239be0c782440bd828cee21dbc2baa1"}\'\r\n'

From this Json file, I need to extract a particular key:value. For example, I need to get the emotionsAll (Key) from the file.

I tried using :

print(data['emotionsAll'][0]['neutral'])

error i got :

Traceback (most recent call last):   File "C:\Users\HP\Downloads\Final Project\getfile.py", line 6, in <module>
    print(data['emotionsAll'][0]['neutral']) TypeError: string indices must be integers

So, Is there any other way to get a particular key:value ?

try `data['emotionsAll']['neutral']`. `emotionsAll` is not a list so you can't access it via integer indices. — Jarek.D, Feb 21 '19 at 10:57
Nope ! That was about how to open a json file . My question is how would i read them as like a dictionary :) @Fabian — , Feb 21 '19 at 10:57
Still i get : Traceback (most recent call last): File "C:\Users\HP\Downloads\Final Project\getfile.py", line 5, in data['emotionsAll']['neutral'] TypeError: string indices must be integers — , Feb 21 '19 at 10:59
@Sai if you check you just read it in wrong ... if you open and load json format correctly you are able to access like dict... — Fabian, Feb 21 '19 at 12:17
tried opening :raise JSONDecodeError("Expecting value", s, err.value) from None json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0) — , Feb 21 '19 at 12:32

bumblebee · Answer 1 · 2019-02-21T11:27:48.403

1

Try using the json package

Contents of file.json

{"image":{"width":750,"height":1127,"orientation":1},"objects":[{"type":"face","boundingBox":{"x":132,"y":180,"height":619,"width":513},"landmarks":{"faceContour":[[162,375],[162,440],[165,504],[175,568],[193,628],[226,686],[265,740],[313,784],[373,799],[436,793],[494,758],[543,712],[586,660],[616,601],[631,534],[639,468],[645,400]],"noseBridge":[[387,396],[385,441],[381,485],[378,532]],"noseBall":[[322,547],[350,560],[380,572],[412,563],[442,554]],"eyebrowRight":[[419,348],[466,329],[516,325],[564,339],[595,377]],"eyebrowLeft":[[197,358],[224,325],[269,315],[316,325],[358,347]],"eyeRight":[[448,419],[479,404],[510,405],[539,416],[511,425],[480,424]],"eyeRightCenter":[[495,416]],"eyeLeft":[[242,402],[269,393],[299,396],[329,412],[297,414],[267,413]],"eyeLeftCenter":[[284,405]],"mouthOuter":[[269,596],[310,598],[349,598],[379,606],[411,601],[456,606],[502,609],[456,663],[412,684],[378,687],[345,680],[307,652]],"mouthInner":[[284,603],[349,610],[379,615],[411,613],[487,614],[412,652],[379,656],[348,648]]},"attributes":{"gender":"male","genderConfidence":0.8385,"age":24,"ageConfidence":0.8419,"emotion":"happiness","emotionConfidence":1.0,"emotionsAll":{"neutral":0.0,"sadness":0.0,"disgust":0.0,"anger":0.0,"surprise":0.0,"fear":0.0,"happiness":1.0},"pose":{"pitch":-5.7105,"roll":0.2941,"yaw":1.8646},"race":{"asian":0.0002,"black":0.0001,"white":0.9989},"eyewear":{"sunglasses":0.0,"glasses":0.0},"hair":{"color":{"blond":0.0,"black":0.9994,"brown":0.0},"cut":{"short":0.9999,"long":0.0,"bald":0.0},"facial":{"beard":0.0,"mustache":0.0,"stubble":0.2543}},"frontal":true}},{"type":"person","boundingBox":{"x":20,"y":60,"height":1053,"width":696}}],"requestId":"1239be0c782440bd828cee21dbc2baa1"}

Code:

import json

with open('file.json', 'rb') as fp:
    json_data = json.load(fp)

print(json_data['objects'][0]['attributes']['emotionsAll']['neutral'])

edited Feb 21 '19 at 11:27

answered Feb 21 '19 at 10:59

bumblebee

1,811
12
19

raise JSONDecodeError("Expecting value", s, err.value) from None json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0) – Feb 21 '19 at 11:03
Will the update the answer soon – bumblebee Feb 21 '19 at 11:07
Sure and Thanks. Will be waiting for the respond – Feb 21 '19 at 11:09
It's working fine for me. Try giving the absolute path of `file.json` file. – bumblebee Feb 21 '19 at 11:09
Still the same : raise JSONDecodeError("Expecting value", s, err.value) from None json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0) – Feb 21 '19 at 11:18
Can you post your `file.json` contents? – bumblebee Feb 21 '19 at 11:26
I have added the `file.json` contents – bumblebee Feb 21 '19 at 11:28
I have printed the whole json file in my question . Do check the Output( Json file) above ! – Feb 21 '19 at 11:30
I think the problem lies with the way the data is stored in the `file.json` file. Copy the contents as I have displayed in my answer and then try running my code. – bumblebee Feb 21 '19 at 11:36
It works fine! But why doesn't it work with old content .Because I wont be able to edit each json file from a 100 files right?! – Feb 21 '19 at 11:45
It's because `.json` file should contain only `json` content. Your output contains `b'b\'` and `\'\r\n'` which creates the problem while using `json.load()`. – bumblebee Feb 21 '19 at 11:47
How is the content being stored in the `files`. Can you share the code which writes the `json` data into the file? – bumblebee Feb 21 '19 at 11:49
`with open('file.txt', 'w') as f: print(result, file=f)` – Feb 21 '19 at 11:58
What is the type of `result`? – bumblebee Feb 21 '19 at 12:21
Its a API json file – Feb 21 '19 at 12:33

chitown88 · Accepted Answer · 2019-02-21T12:41:11.317

0

A couple things:

1 - the emotionsAll key is within the objects key, first element in the list [0], attributes key

2 - Your json file was written with the bytes prefix, so when it's being read, it starts your string with b'. You can either a) have that file written without that mode by decoding/encoding, or just manipulate that string.

import json

data = repr(open('file.json', 'rb').read())

data = data.split('{', 1)[-1]
data = data.rsplit('}', 1)[0]

data = ''.join(['{', data, '}'])
jsonObj = json.loads(data)

print(jsonObj['objects'][0]['attributes']['emotionsAll']['neutral'])

Output:

print(jsonObj['objects'][0]['attributes']['emotionsAll']['neutral']) 
0.0

edited Feb 21 '19 at 12:41

answered Feb 21 '19 at 10:59

chitown88

27,527
4
30
59

It Works only if the json file content is defined in the json_str . But when i used the same from a external json file (i.e data = repr(open('file.json', 'rb').read()) ) , I doesn't give the same ! – Feb 21 '19 at 11:04
@Sai, true, but I was addressing the other issue of `TypeError: string indices must be integers`. But maybe it's the binary mode that is causing the issue? Look at the edit in the solution and see if that works – chitown88 Feb 21 '19 at 11:18
data = repr(open('file.json', 'r').read()) works but once i try print(data['objects'][0]['attributes']['emotionsAll']['neutral']) it doesnt return the value . Instead it gives a error : TypeError: string indices must be integers...... with open('file.json') as fp: data = json.load(fp) when i tried this .. i got :::: Still the same : raise JSONDecodeError("Expecting value", s, err.value) from None json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0) – Feb 21 '19 at 11:22
I have Send the json file to your email . Please do check it :) – Feb 21 '19 at 11:35
Thanks a lot ! Work fine now :) – Feb 21 '19 at 12:44
I still think a better way would be to make sure that API json file is written without that bytes prefix, but in the mean time, this is a work around – chitown88 Feb 21 '19 at 12:47

Reading a Json in python

2 Answers2