Ruby/Rails: Convert Int to Time or Get Time from Integer

Ruby / Rails: convert int to time OR get time from integer?

Use Time.at:

t = Time.at(i)

How do I convert this Time integer to a Date in Ruby?

Use Time.at for this:

t = Time.at(i)

Convert number to date in Ruby

DateTime.strptime('1512387277084', '%Q')
#⇒ #<DateTime: 2017-12-04T11:34:37+00:00
#       ((2458092j,41677s,84000000n),+0s,2299161j)>

DateTime formatting.

Create TimeWithZone object from integer (unix epoch time with millisecond precision) and with specified zone (string)

Assuming that the timestamp is in milliseconds, then 1586653140000 is

Epoch: 1586653140
  GMT: Sunday,   April 12, 2020 12:59:00 AM 
  PDT: Saturday, April 11, 2020 17:59:00 PM -in time zone America/Los Angeles

These are just 3 different ways to refer to a specific point in time around the world.
Sat, 11 Apr 2020 20:59:00 PDT -07:00 and 2020-04-11 20:59:00 -0400 each refer to different points in time and not the same as epoch(1586653140)

Since the Unix epoch (or Unix time or POSIX time or Unix timestamp) is the number of seconds that have elapsed since January 1, 1970 (midnight UTC/GMT), it wouldn't make sense to take 1586653140 and only change the time zone without adding the zone's offset because now you are talking about another point in time.

To get the right "translation" from the epoch to any time zone you could just do

Time.zone = "GMT"
Time.zone.at(1586653140)
=> Sun, 12 Apr 2020 00:59:00 GMT +00:00
Time.zone = "America/Los_Angeles"
Time.zone.at(1586653140)
=> Sat, 11 Apr 2020 17:59:00 PDT -07:00

When working with dates in time zones in rails it is important to only use functions that take the set time zone into account:

DON’T USE

• Time.now
• Date.today
• Date.today.to_time
• Time.parse("2015-07-04 17:05:37")
• Time.strptime(string, "%Y-%m-%dT%H:%M:%S%z")

DO USE

• Time.current
• 2.hours.ago
• Time.zone.today
• Date.current
• 1.day.from_now
• Time.zone.parse("2015-07-04 17:05:37")
• Time.strptime(string, "%Y-%m-%dT%H:%M:%S%z").in_time_zone

Also keep in mind that in a Rails app, we have three different time zones:

• system time,
• application time, and
• database time.

This post by thoughtbot explains things clearly.

Rails – Convert time duration to integer

You can calculate the seconds as below :

require 'time'

t = Time.parse("00:00:14.01")
sec = t.hour*3600 + t.min*60 + t.sec
sec # => 14

Important method sets here are - Time#hour, Time#min, Time#sec.

As @ChrisHeald suggested -

 t = Time.parse("00:00:14.01") - Time.parse("00:00:00")

---

Related Topics