Converting UTC timestamp to ISO 8601 in Ruby

ruby-on-rails ruby timestamp
ming yeow picture ming yeow · Oct 30, 2010 · Viewed 59.8k times · Source

I have a timestamp that is in UTC

"2010-10-25 23:48:46 UTC"

I need to convert it into ISO 8601

"2010-10-29 06:09Z"

The documentation is confusing as hell - what is the easiest way to do that?

Answer

Ryan Bigg picture Ryan Bigg · Oct 30, 2010

I think you're trying to trick us.

The input date to your question is the 25th of October, 2010, whilst the output is the 29th of October, 2010. Well played!

Continuing on this nit-picking thread: your times are also completely different and you're missing the seconds from the output time.

Now for the true answer.

A little factoid first though: the ISO 8601 output in Ruby is similar to the "Combined date and time" output from ISO 8601's Wikipedia page.

You've got a string and so you'll need to convert it into a Time object which you can do with to_time. Then it's simply a matter of calling iso8601 on that object to get the ISO 8601 version:

"2010-10-25 23:48:46 UTC".to_time.iso8601

The to_time method is courtesy of Rails, whilst the iso8601 is courtesy of Ruby's standard library.

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