Using moment.utc() incorrectly converting the date into utc format of “days” format-Moment Javascript

Question

I'm using moment library to convert date into a utc format. here is my date string:

var dateString = "2019-01-31T11:33:16.952+0000";

new Date("2019-01-31T11:33:16.952+0000") // o/p: Thu Jan 31 2019 03:33:16 GMT-0800 (Pacific Standard Time) since this date is less than a week from today's date, I'm trying to display a text saying "n days ago" instead of actual date. But for some reason I'm getting a future date displayed as "6 days ago" when I do this:

moment.utc("2019-01-31T11:33:16.952+0000").local().fromNow() // shouldnt this display "5 days ago"??

Not sure why moment is not converting the date correctly, any ideas what could be wrong here?

Answer 1

I guess(Considering use of local() converts to your local timezone so time is deducted because you might be in -ve TimeZone) this answer is a solution you're expecting:

Ideally, you would want to pass a UTC timestamp from your server to the client. That doesn't mean you have to switch your whole server over to UTC, it just means that you would convert from the time in your database to UTC on the server before sending it over the web. Sure, it would be even better if you actually stored times in UTC, but you said you aren't in a position to make that sort of change right now. But let's just work off the assumption that you can't change anything at all on the server.

We'll also assume that your server is fixed to the UTC-07:00 offset. In real life, this would only be true for places like Arizona that don't follow daylight saving time. So if you are in Los Angeles and are in Pacific Time, then some of your data is based on UTC-07:00, but some of it is based on UTC-08:00. That requires a lot more work if you want to do it in JavaScript.

Let's also assume that the input is already a string in ISO8601 format. (If it's not, then let me know and I will adjust this code.)

var s = "2013-09-11 18:00:00"; // from action.timeStamp

var actionTime = moment(s + "-07:00", "YYYY-MM-DD HH:mm:ssZ");

var timeAgo = actionTime.fromNow(); The reason your other code didn't work is because in the first line, you are affected by the time zone of the browser. The zone setter in the second line just changes the zone for formatting, not changing the actual moment in time.

Also, when you dump a moment to the console for debugging, make sure you format it for output. Otherwise you are just looking at its internal property values, which may or may not make sense directly.