I'm developing a node.js function that lists the objects in an S3 Bucket via the listObjectsV2 call. In the returned json results, the date is not the same as the date shown in the S3 bucket nor in a aws cli s3 list. In fact, they are different days. I'm not sure how this is happening?
Any thoughts?
aws cli ls
aws s3 ls s3://mybucket
2018-11-08 19:38:55 24294 Thought1.mp3
S3 Page on AWS
JSON results
They are the same times, but in different timezones.
The listObjectsV2 response is giving you Zulu times (UTC or Greenwich Mean Time), which appears to be 6 hours ahead of you.
In the JSON picture you have 2018-11-09T01:38:55.000Z which is ZULU time (the Z at the very end). It means UTC/GMT time.
In the S3 console picture you have Nov 8, 2018 7:38:55 PM GMT-0600 - this time is GMT time minus 6 hours (see at the end GMT-0600) - which may be possibly the US EST time or similar. The difference between these two is exactly 6 hours.
The output from aws CLI is probably on your local computer and shows local time in the 24H format without the timezone, so it is harder to see the reason, but it matches the S3 console time.
In general, AWS returns times in the UTC time zone. This is usually quite helpful once you start deploying in multiple time-zones. On the other side, it may become tricky if you for example run your code on an EC2 instance where is configured a different timezone. So be careful when you convert from your local time to the UTC time - I would suggest you to even use some library like https://momentjs.com/ or you may create yourself more problems.
