JSON format:

[{"SH_MSG": {"time": "1657291114000", "area_id": "D1", "address": "54", "msg_type": "SH", "data": "8CFB0B00"}}, {"SF_MSG": {"time": "1657291114000", "area_id": "D2", "address": "0A", "msg_type": "SF", "data": "1F"}}, ...}][...]

I want to record all data that has a CA_MSG tag at the start.

I am using stomp to obtain messages.

msg = json.loads(frame.body)

msg is a list such that:

msg = [{'SF_MSG': {'...'}}, ...]

I am trying:

for m in msg:
    new_msg = []
    if m.keys() == 'CA_MSG':
         new_msg.append(m)

But this is just returning [] every time.

CodePudding user response：

I ended up getting there in the end by skipping out the for loops for a list comprehension:

CA_MSGS = [msg['CA_MSG'] for msg in message if 'CA_MSG' in list(msg.keys())]

CodePudding user response：

dict.keys() returns a list object, it can never be a True if you check the list object with a string object

if m.keys() == 'CA_MSG': # False all the time

# probably this is what you are looking for

if m.keys().count('CA_MSG') > 0: