bytes to json - Printable Version

bytes to json - Printable Version

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bytes to json - GrahamL - Dec-04-2020

Hi
I am trying to send json data over a pipe but cannot get it quite right
Send

mesages = [{"id": "1", "txt": "message 1", "start_date": "2014-02-09", "start_time": "16:20", "duration": "01:00"}]
        win32file.WriteFile(handle,     str.encode(json.dumps(mesages), encoding="ascii"))

receive

 result, data = win32file.ReadFile(p, 65535)
            json_data = json.dumps(data.decode('ascii'))
            print(json_data['first_name'])

This gives me this error
[error
TypeError: string indices must be integers
[/error]

What is the correct way of doing this?

RE: bytes to json - ndc85430 - Dec-04-2020

Shouldn't you be calling loads, rather than dumps to decode the JSON string into Python objects?

RE: bytes to json - GrahamL - Dec-04-2020

I still get TypeError: string indices must be integers

RE: bytes to json - DeaD_EyE - Dec-04-2020

import json

mesages = [{"id": "1", "txt": "message 1", "start_date": "2014-02-09", "start_time": "16:20", "duration": "01:00"}]
payload = json.dumps(mesages).encode("ascii")
print(payload)
print(type(payload))

# json can also loads bytes
# but here the encoding is not explicit
data = json.loads(payload)

data2 = json.loads(payload.decode("ascii"))

print(data2)

Output:b'[{"id": "1", "txt": "message 1", "start_date": "2014-02-09", "start_time": "16:20", "duration": "01:00"}]'
<class 'bytes'>
[{'id': '1', 'txt': 'message 1', 'start_date': '2014-02-09', 'start_time': '16:20', 'duration': '01:00'}]

RE: bytes to json - GrahamL - Dec-04-2020

Hi
Yes this works, but I am reading from a pipe using

result, data = win32file.ReadFile(p, 65535)

This gives me the string

b'"{\\"success\\": \\"true\\", \\"status\\": 200, \\"message\\": \\"Hello\\"}"'

I then decode

d = data.decode('ascii')

Then I do a json load

json_data = json.loads

but when I try to access as a json object I get the error

TypeError: string indices must be integers

RE: bytes to json - GrahamL - Dec-04-2020

How can access the result as a json object

result, data = win32file.ReadFile(p, 65535)
json_data = json.loads(data)
print(json_data['success'])

- This gives TypeError: string indices must be integers

RE: bytes to json - buran - Dec-04-2020

this will work

import json
spam = b'"{\"success\": \"true\", \"status\": 200, \"message\": \"Hello\"}"'
print(spam.decode())
data = json.loads(spam.decode()[1:-1])
print(data['success'])

but I think there is problem with the data being send/receive - i.e. extra quotes. Probably on the sending site you make too many conversions

RE: bytes to json - GrahamL - Dec-04-2020

Here is my sending code

s = '{"success": "true", "status": 200, "message": "Hello"}'
win32file.WriteFile(handle,     str.encode(json.dumps(s)))

RE: bytes to json - buran - Dec-04-2020

yep, s is already a JSON string, no need to dump it again

win32file.WriteFile(handle, s.encode())

s = {"success": "true", "status": 200, "message": "Hello"}
win32file.WriteFile(handle, json.dumps(s).encode())

then on receiving end

data = json.loads(spam.decode())

Also, didn't work with win32file.WriteFile, not sure if you can skip also encode/decode part

RE: bytes to json - GrahamL - Dec-04-2020

That was it - thanks