fix: add timezone to timestamps

[rasendubi]

---

labels: mergeable

Fixes: #issue

Motivation and Context

This fixes timestamps, so they get properly serialized with timezone information.

Description

>>> datetime.datetime.now(datetime.timezone.utc).isoformat()
'2024-08-20T17:58:45.374349+00:00'
>>> datetime.datetime.utcnow().isoformat()
'2024-08-20T18:01:31.482134'

How has this been tested?

Not tested.

[leoromanovsky]

A desirable test would be to refactor this into a function and the unit test would have consistent time:

import unittest
import datetime
from freezegun import freeze_time

def get_utc_timestamp():
    return datetime.datetime.now(datetime.timezone.utc).isoformat()

class TestUTCTimestamp(unittest.TestCase):
    @freeze_time("2023-08-20 14:30:45.123456+00:00")
    def test_get_utc_timestamp(self):
        expected = "2023-08-20T14:30:45.123456+00:00"
        result = get_utc_timestamp()
        self.assertEqual(result, expected)

    def test_timezone_present(self):
        result = get_utc_timestamp()
        self.assertIn('+00:00', result)

    def test_iso_format(self):
        result = get_utc_timestamp()
        try:
            datetime.datetime.fromisoformat(result)
        except ValueError:
            self.fail("get_utc_timestamp() did not return a valid ISO format")

[rasendubi]

I added two higher-level tests asserting that event timestamps carry the timezone information (ultimately, we don't care whether string uses +00:00 or Z suffix):

event = mock_logger.log_assignment.call_args.args[0]
timestamp = datetime.datetime.fromisoformat(event["timestamp"])
assert timestamp.tzinfo == datetime.timezone.utc

[schmit]

Great catch -- perhaps we should refactor into a get_time() function (probably with a better name) and call that so we don't risk calling the wrong function in the future (although of course we could forget that the get_time function exists...

Also don't forget a version bump!

[rasendubi]

@schmit we actually have a good utcnow() in eval.py.

I'm signing off for today so didn't have much time for a nice fix with tests. I can improve it tomorrow or feel free to pick it up

[rasendubi]

@schmit @leoromanovsky refactored this into a function + added tests

[leoromanovsky]

👍 👍 👍