Timezone support for viewer and API

[TheVaan]

Hey!

I would appreciate support for timezones for the viewer and the API. Currently, daily active users are grouped for UTC dates. For our product, we need daily active users for UTC+02:00. For our requests for a specific date, we're grouping unique active users between (dd-1)-mm-yyyyT22:00:00 and dd-mm-yyyyT22:00:00. But we also have some use cases where we want to get data for a timespan (a week / a month / ...). It would be awesome telling the api at which timezone we and the api groups the data automatically correct. Currently we need to request each day separate, which results in unnecessary high traffic and long loading times. The difference between daily active users in UTC and UTC+2 is noticeable and has an impact on our decisions. I think someone in timezone with +/-7 has even more impact, because a users in the morning/night are grouped to the wrong "timezone day".

Best regards
Jan

[winsmith]

Thanks for the request! I like the idea, and I'll add it to the roadmap, but it might be a while before we get around to it since we're busy with funnels, retention charts and more "smartness".

Note to others: If you think this is super important, comment here so I know we should prioritise it higher <3

Note to self: https://druid.apache.org/docs/latest/querying/granularities.html

[nighthawk]

+1 on this.

We are using TelemetryDeck for an app that is exclusively used in Australia. It would be nice, if it was possible to specify a timezone on the bar/line charts so that for example the "day" granularity looks more like an Australian than a European day.

[johnwilke2]

+1 as well

[sahandnayebaziz]

+1 to this, I currently have to do a lot of mental reminders that my DAU aren’t dropping off dramatically every day. That’s how the graph makes it look for me in PST, but it’s just a quirk of the fact that there is a hardcoded time zone for what a “day” is

[SpencerLynn]

+1. I'm in the US Central Time zone (UTC-5 during DST), and it's weird to view daily numbers of any kind.

Being able to adjust for my time zone would be great.

If that isn't possible or won't be for a while, I'd love to gain some insight into what "time zone day" the data is being displayed for. For example, when it says "Thursday October 2nd" what exact times is that for? It's currently 11:45pm CDT. But data seems to be still aggregating for October 2nd. If the "time zone day" was 12am-11:59pm UTC, shouldn't the day have already ended and October 3rd data be coming in?

Thanks!

Update:
I've read the mentioned issue and gathered the times are always UTC. And then the UI tries to adjust that time to my system's time zone. So for me that would be 19:00 (CDT is UTC-5).

However, still curious about one more detail. Does the day marker mark the beginning or the end of the day? For example, when the UI says Thursday October 2nd, what UTC times does that correlate to? As mentioned above, data is still aggregating for that date and it's already the next day for CDT, and way past it for UTC. I think it would be less confusing to just see everything relative to UTC. At least until the actual data "days" could be adjusted to match my system time. Right now it feel very confusing because it's a mix of UTC data but it's unclear how the UI is presenting it.