Why I'm getting UTC(+00:00) even I'm runnning my aws lambda at ap-northeast-2 region?

Question

I'm running lambda at region ap-northeast-2

this is part of my code, getting a timestamp for DynamoDB

import datetime
a = datetime.datetime.now().astimezone().replace(microsecond=0).replace(second=0).isoformat()

if I run this, I get "2021-12-25T15:33:00+00:00"

while I get "2021-12-26T00:34:00+09:00" on my laptop.

I thought that lambda will return same as mine because I'm at Seoul so does ap-northeast-2 region is there a reason why I couldn't get my timezone?

"2021-12-25T15:33:00+00:00" and "2021-12-26T00:33:00+09:00" are the same time. — matt, Dec 25 '21 at 15:43
@matt I know it's the same time, I was asking why aws's python is giving me +00:00, not +09:00 — ccppoo, Dec 25 '21 at 15:47

score 1 · Accepted Answer · answered Dec 25 '21 at 16:20

Lambda instances always use UTC as their time zone, see https://docs.aws.amazon.com/lambda/latest/dg/configuration-envvars.html under Reserved Environment Variables: TZ.

It would be awkward if the time zone switched depending on the region where you run.

Related: AWS Lambda Timezone (the link above came from the comments on that question).

1 Answers1