How to skip text at the beginning of a json file in python - json

Question

I have a json object file and at the beginning of this file a header of text, date, time, IP address.
I've tried f.readlines()[5:] to no avail.
I've tried next(f)
I wish to skip 5 or 6 lines of text and go directly into the json data.
Here is an example.
import jsonlines
import json
data_file = input("Enter a file to parse: ")
with jsonlines.open(data_file) as file:
for obj in file:
try:
jsonparse = json.loads(obj)
except Exception as e:
pass
print(obj)
Error:
jsonlines.jsonlines.InvalidLineError: line contains invalid json: Expecting value: line 1 column 1 (char 0) (line 1)
Top of json file:
Start: 07/02/2019 14:59:40.686
Connected To:
192.168.11.203
Here is the full long error:
Enter a file to parse: Play.raw
Traceback (most recent call last):
File "C:\Users\sdickey\AppData\Local\Programs\Python\Python37\lib\site-packages\jsonlines\jsonlines.py", line 159, in read
value = self._loads(line)
File "C:\Users\sdickey\AppData\Local\Programs\Python\Python37\lib\json\__init__.py", line 348, in loads
return _default_decoder.decode(s)
File "C:\Users\sdickey\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\sdickey\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)
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "C:/Users/sdickey/PycharmProjects/Python Testing/Actall Data/testing.py", line 6, in <module>
for obj in file:
File "C:\Users\sdickey\AppData\Local\Programs\Python\Python37\lib\site-packages\jsonlines\jsonlines.py", line 204, in iter
skip_empty=skip_empty)
File "C:\Users\sdickey\AppData\Local\Programs\Python\Python37\lib\site-packages\jsonlines\jsonlines.py", line 164, in read
six.raise_from(exc, orig_exc)
File "<string>", line 3, in raise_from
jsonlines.jsonlines.InvalidLineError: line contains invalid json: Expecting value: line 1 column 1 (char 0) (line 1)
Process finished with exit code 1

Answer 1

It is always preferable not to read the whole file in memory but one line at a time.
Assuming your input file contains:
first line
second line
third line
fourth line
fifth line
{ "k1": "val1", "k2": "val2" }
{ "k3": "val3", "k4": "val4" }
if you just want to skip 5 lines, you could do it brutally as:
import json
with open("test.txt") as f:
for _ in range(5):
next(f)
for line in f:
obj = json.loads(line)
print(obj)
or using enumerate:
import json
with open("test.txt") as f:
for i, line in enumerate(f):
if i<5:
continue
obj = json.loads(line)
print(obj)
or use itertools' dropwhile:
import itertools as it
import json
with open("test.txt") as f:
for i, line in it.dropwhile(lambda i: i[0]<5, enumerate(f)):
obj = json.loads(line)
print(obj)

Answer 2

I think you are trying to convert to json line by line. You need to join all lines by \n igoring the first 5 lines and then load it:
import json
with open("test.txt") as f:
json_obj = "\n".join(f.readlines()[5:])
jsonparse = json.loads(json_obj)
print(jsonparse)