Rails jbuilder DateTime adding decimals to second

Question

I'm using JBuilder to render the views of the JSON API part of my application. The problem I'm running into is that my DateTimes are being rendered like this:

"2013-07-02T17:03:18.000Z"

...when what I really want is this:

"2013-07-02T17:03:18Z"

I'm not sure where those decimals are coming from...

I'm rendering the field in the typical JBuilder way:

json.my_datetime_field

I have a date format initializer in my app:

Date::DATE_FORMATS[:default] = '%Y/%m/%d %Z'
Time::DATE_FORMATS[:default] = '%Y/%m/%d %H:%M:%S %Z'
Date::DATE_FORMATS[:month_day_year] = '%m-%d-%Y'

However, this doesn't seem to impact JBuilder, and that is good. I want ISO8601 format coming from my API. I'm on Rails 4.0.0 final, by the way.

Not sure about JBuilder's settings, but FYI - fractional second decimals are allowed in ISO8601. 3 places are common, but so are 6 or 7 places. — Matt Johnson-Pint, Jul 03 '13 at 14:53
Yeah, I caved and changed my client-side parser's date formatter to allow for fractional seconds. I'll leave this question here in case anyone knows how to actually change jbuilder's output. The closest I've come is monkey-patching DateTime to return what I want with "as_json", but that seems really hacky. — elsurudo, Jul 04 '13 at 13:12

score 11 · Accepted Answer · answered May 14 '14 at 11:43

11

using under rails? to avoid encode with float, run this method on initialize block on your project

ActiveSupport::JSON::Encoding.time_precision = 0

answered May 14 '14 at 11:43

shao1555

126
1
3

score 4 · Answer 2 · answered Oct 21 '13 at 04:46

I've experienced this while trying to render a format more amenable to iPhone applications. You could use the .strftime method.

json.my_datetime_field(object.timestamp.strftime('%Y/%m/%d %H:%M:%S %Z'))

will create a json field called my_datetime_field

{ "my_datetime_field": timestamp_goes_here  }

score 1 · Answer 3 · edited Apr 16 '15 at 22:22

This work for me.

/view/api/earthquakes/index.json.jbuilder

json.array!(@earthquakes) do |earthquake|
  json.extract! earthquake, :id,
                :name,
                :magnitude,
                :lat,
                :lon,
                :city,
                :region,
                :state,
                :country,
                :usgs_id,
                :usgs_url,
                :usgs_url_detail,
                :num_structures

  json.date(earthquake.date.strftime('%Y-%m-%d %H:%M:%S %Z'))

end

Rails jbuilder DateTime adding decimals to second

3 Answers3