[BUG] Wrong parsing of Twitch timestamps if running lib not in UTC timezone #252
Description
Basic information
- Program version: 0.2.8
- Python version: 3.11.9
- Operating system: Linux/Windows
Describe the bug
The chat_downloader.utils.core.timestamp_to_microseconds function, which is used only in sites/twitch.py, doesn't parse the TZ marker (Z) properly. Because of this, the resulting microseconds value is shifted out of UTC by the TZ of the current python process.
Command/Code used
Reproducing scripts:
port datetime, time, os
from chat_downloader.utils.core import timestamp_to_microseconds
now = datetime.datetime.now()
test_timestamp = "2024-06-30T00:35:54.54Z"
wrong = timestamp_to_microseconds(test_timestamp)
# Fix variant #1
import re
info = list(filter(None, re.split(r'[\.|Z]{1}', test_timestamp))) + [0]
fixed1 = round((datetime.datetime.strptime(f'{info[0]}Z', '%Y-%m-%dT%H:%M:%S%z').timestamp() + float(f'0.{info[1]}')) * 1e6)
# ^^ fix
# Fix variant #2 (it applies ISO 8601 instead of RFC3339)
fixed2 = int(datetime.datetime.fromisoformat(test_timestamp).timestamp() * 1e6)
print(
f"{os.environ['TZ']=}\n"
f"{time.tzname=}\n"
f"----\n"
f"{now=}\n"
f"{now.tzinfo=}\n"
f"{now.tzname()=}\n"
f"{now.timetz()=}\n"
f"{now.astimezone()=}\n"
f"----\n"
f"{test_timestamp=}\n"
f" {wrong=}\n"
f"{fixed1=}\n"
f"{fixed2=}\n",
flush=True
)My local output:
os.environ['TZ']='America/Chicago'
time.tzname=('CST', 'CDT')
----
now=datetime.datetime(2024, 7, 22, 18, 49, 55, 724731)
now.tzinfo=None
now.tzname()=None
now.timetz()=datetime.time(18, 49, 55, 724731)
now.astimezone()=datetime.datetime(2024, 7, 22, 18, 49, 55, 724731, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=68400), 'CDT'))
----
test_timestamp='2024-06-30T00:35:54.54Z'
wrong=1719725754540000
fixed1=1719707754540000
fixed2=1719707754540000
Expected behavior
The value must be 1719707754540000.
Additional context/information
Only Python 3.7 is appropriate to fix the problem because %z and datetime.datetime.fromisoformat() appears at 3.7.