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builtins.StopIteration: 2 and json.decoder.JSONDecodeError: Expecting value: line 2 column 1 (char 2) errors

I have a JSON file I am trying to import into MongoDB.
Using the python code from the [documentation][1], I get an error on myDict = json.loads(jsonObj) (see traceback below). I have used an online tool to validate my JSON and it is marked as valid. The problem seems to be in line 2 but I have no idea what to do to make this work. Please help!
Python traceback:
obj, end = self.scan_once(s, idx)
builtins.StopIteration: 2
During handling of the above exception, another exception occurred:
File "/Users/s/Documents/s/importToMongo.py", line 13, in <module>
myDict = json.loads(jsonObj)
File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/json/__init__.py", line 346, in loads
return _default_decoder.decode(s)
File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/json/decoder.py", line 337, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/json/decoder.py", line 355, in raw_decode
raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 2 column 1 (char 2)```
**My JSON:**
```[
{
"field1": "6405441",
"field9": "326",
"field10": "12",
"field17": "1180",
"field22": "Avenue Brugmann",
"field23": "Brugmannlaan",
"field24": null,
"field28": "Uccle",
"field29": "Ukkel",
"field30": null,
"field13": "648301.355 666355.729"
},
{
"field1": "fid",
"field9": "housenumber",
"field10": "boxnumber",
"field17": "postal_info_objectid",
"field22": "streetname_fr",
"field23": "streetname_nl",
"field24": "streetname_de",
"field28": "municipality_fr",
"field29": "municipality_nl",
"field30": "municipality_de",
"field13": "position"
}
]```
[1]: https://www.mongodb.com/compatibility/json-to-mongodb

Problem was this code only works for JSON objects with this format:
No brackets ( [] )
No commas at the end of the last field-value pair
Only one object
Example:
{
"field1":"value",
"field2":"value"
}

How to solve problem during reading of a json file in Python?

I`m currently programming an automated wateringsystem using Python on a Raspberry Pi. For that I want to read the content of a json file, with the following code:
import logging
import json
try:
with open('/var/www/BWSWebApp/apictx.json') as file:
jsondata = json.load(file)
except FileNotFoundError:
print('Error: File not found (ln 35)')
_logging = jsondata['main']['logging']
if _logging == True:
_logging = '/home/pi/Desktop/BewaesserungssystemV3/data/info_log.log'
else:
_logging = None
The json file is containing the following:
{
"main": {
"active": true,
"watering": false,
"fwatering": false,
"ffminwatering": false,
"humidity": 24,
"temp": 17.6,
"battery": 100,
"logging": true,
"last_watering": "27.08.2021 16:15:39",
"l_day": 0,
"day": 0,
}
}
If I run the program, I get the following error:
Traceback (most recent call last):
File "/home/pi/Desktop/BewaesserungssystemV3/main.py", line 6, in <module>
jsondata = json.load(file)
File "/usr/lib/python3.7/json/__init__.py", line 296, in load
parse_constant=parse_constant, object_pairs_hook=object_pairs_hook, **kw)
File "/usr/lib/python3.7/json/__init__.py", line 348, in loads
return _default_decoder.decode(s)
File "/usr/lib/python3.7/json/decoder.py", line 337, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File "/usr/lib/python3.7/json/decoder.py", line 353, in raw_decode
obj, end = self.scan_once(s, idx)
json.decoder.JSONDecodeError: Expecting property name enclosed in double quotes: line 14 column 9 (char 316)
What am I doing wrong?
Thanks, Jannis

You need to remove the comma after the last value ie day: 0.
You can use JSON online validator if you encounter problems like these in the future.
{
"main": {
"active": true,
"watering": false,
"fwatering": false,
"ffminwatering": false,
"humidity": 24,
"temp": 17.6,
"battery": 100,
"logging": true,
"last_watering": "27.08.2021 16:15:39",
"l_day": 0,
"day": 0
}
}

Why am I getting a JSONDecodeError when trying to load a JSON file in Python?

I'm trying to load a JSON file in to Python, but it's giving me an JSONDecodeError error which seems to suggest the file is empty... which I know is not true.
I've reviewed similar questions I can find on here (65466227 & 62286816), and while one or two provide useful alternatives... that's not really the point. I feel like what I'm doing should work but it doesn't.
I put my JSON in to jsonlint.com and it confirmed that my JSON is indeed valid.
Error message/traceback:
Traceback (most recent call last):
File "utils/fmt_test.py", line 62, in <module>
test_cases_json = json.load(jf)
File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/json/__init__.py", line 296, in load
parse_constant=parse_constant, object_pairs_hook=object_pairs_hook, **kw)
File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/json/__init__.py", line 348, in loads
return _default_decoder.decode(s)
File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/json/decoder.py", line 337, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/json/decoder.py", line 355, in raw_decode
raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)
My Python code:
test_case_file, _ = os.path.splitext(fmt_file)
test_case_file = f"{test_case_file}.json"
if os.path.isfile(test_case_file):
with open(test_case_file, "r") as jf:
test_cases_json = json.load(jf)
My JSON:
{
"tests": [
{
"id": "746fd83s23dy",
"event": "%t LFA_DUMMYSTRING LFA_DUMMYSTRING TEST LFA_DUMMYSTRING1 LFA_DUMMYSTRING2 TEST2 LFA_DUMMYSTRING",
"match": "True"
},
{
"id": "990gb98s34dm",
"event": "%t LFA_DUMMYSTRING LFA_DUMMYSTRING1 LFA_DUMMYSTRING2",
"match": "True"
},
{
"id": "100ma09x31ui",
"event": "%t localhost LFA_DUMMYSTRING1 LFA_DUMMYSTRING2 TEST3 LFA_DUMMYSTRING1 LFA_DUMMYSTRING2",
"match": "True"
}
]
}
Any help is much appreciated, thanks.

There is likely a UTF-8 BOM encoded at the beginning of the file since it is complaining about the first byte. Open with encoding='utf-8-sig' and it will be removed if present:
>>> import json
>>> data = {}
>>> with open('test.json','w',encoding='utf-8-sig') as f: # write data with BOM
... json.dump(data,f)
...
>>> with open('test.json') as f: # read it back
... data2 = json.load(f)
...
Traceback (most recent call last):
<traceback removed>
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0) # same error
>>> with open('test.json',encoding='utf-8-sig') as f:
... data2 = json.load(f)
...
>>> # worked

"json.decoder.JSONDecodeError" when printing json file dictionary in python script

My JSON file looks like this with filename as constants.json:
[
{
"PK": "abc",
"SK": "def",
"label": "eee",
"value": "fgh",
}
]
To read and print this in my python file, I used this code:
import json
with open('constants.json') as file1:
data=json.load(file1)
for item in data:
print(item)
I am getting an error when running the python file in visual studio code
File "<stdin>", line 2, in <module>
File "C:\Users\AppData\Local\Programs\Python\Python37\lib\json\__init__.py", line 296, in load
parse_constant=parse_constant, object_pairs_hook=object_pairs_hook, **kw)
File "C:\Users\AppData\Local\Programs\Python\Python37\lib\json\__init__.py", line 348, in loads
return _default_decoder.decode(s)
File "C:\Users\AppData\Local\Programs\Python\Python37\lib\json\decoder.py", line 337, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File "C:\Users\AppData\Local\Programs\Python\Python37\lib\json\decoder.py", line 355, in raw_decode
raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)
>>> for item in data:
... print(item)

When you receive this kind of error:
raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)
Your first instinct should be to check if the JSON is valid, because that error means Python's json decoder couldn't parse your JSON file properly. One way to validate your JSON file is to post it on https://jsonlint.com/, and posting that constants.json would show up with this error:
Error: Parse error on line 5:
..., "value": "fgh",}]
--------------------^
Expecting 'STRING', got '}'
The error is a bit cryptic, but that site offers some hints at the bottom of the page:
Common Errors
Expecting 'STRING' - You probably have an extra comma at the end of your collection. Something like { "a": "b", }
Expecting 'STRING', 'NUMBER', 'NULL', 'TRUE', 'FALSE', '{', '[' - You probably have an extra comma at the end of your list. Something
like: ["a", "b", ]
And as llamaking136 pointed out in their answer, the error is from the trailing comma after "fgh",.
Since you also mentioned Visual Studio Code, the IDE provides built-in linting of your JSON files, and if there are any errors, it will shows up with red squiggly lines and display a list of errors on the Problems tab:
So you can see and resolve the problem even before running any code.

You have an error in your JSON, line 6.
The dictionary ends with a comma, and the JSON interpreter expects another value after that, but it reaches the end before it can find it.
[
{
"PK": "abc",
"SK": "def",
"label": "eee",
"value": "fgh"
}
]

Read json file get error json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

I try to read data from my json file. First I convert my xml file to json and I get in output this json file for example :
[
{
"ABC": {
"idObjet": "AffleurantEnveloppePCRS.0",
"nature": "03",
"precisionPlanimetrique": "010",
},
"reseau": "DECH",
"thematique": "10"
},
"xmlns:fn": "http://www.w3.org/2005/xpath-functions",
},
{
"DEF": {
"enveloppe": {
"xlink:href": "GEOMETRIE.ENV.AffleurantEnveloppePCRS.0"
},
"gml:id": "GEOMETRIE.AffleurantEnveloppePCRS.0"
},
"xmlns:fn": "http://www.w3.org/2005/xpath-functions",
}
]
Then I try to print some data from this file. I use json.loads() to read this data:
import xmltodict
import json
dict = xmltodict.parse(open('Testv2.gml').read(), attr_prefix='')
dict3 = json.loads('test.json', strict=False)
print(dict3.keys())
with open('test.json', "wt", encoding='utf-8', errors='ignore') as f:
json.dump(dict, f, indent=4, sort_keys=True)
I try to print only keys (ABC and DEF)
ERROR :
Traceback (most recent call last):
File "C:/test.py", line 7, in <module>
dict3 = json.loads('test.json', strict=False)
File "C:\AppData\Local\Programs\Python\Python38-32\lib\json\__init__.py", line 370, in loads
return cls(**kw).decode(s)
File "C:\AppData\Local\Programs\Python\Python38-32\lib\json\decoder.py", line 337, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File "C:\AppData\Local\Programs\Python\Python38-32\lib\json\decoder.py", line 355, in raw_decode
raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)