Make localization operation optional

[porschelau-old]

We have an application which operates solely on UTC time despite of the fact that we have works in PST as well as EST. We are running into issues where we really just want the date picker to show the date in UTC mode rather than localizing it by default.

I am proposing that we offer this as a parameter option.

[Narretz]

Can you elaborate on this? Is your datepicker a custom directive or is it perhaps part of http://angular-ui.github.io/bootstrap/#/datepicker? (If it's part of angular-ui, you should post your issue in their repository, as it is a 3rd party module and this here is the core angular repo)

[porschelau-old]

I submitted a ticket on angular ui datepicker as well. They are using the date filter to post process the date selected by the user.

The issue I am encountering is that the date filter always automatically localize the time string that is passed to it. In my case, I am in PST. If i pass in a string: 2014-05-01T00:00:00Z0000, and i want to format the date to "yyyy-mm-dd". The filter will return 2014-04-30 because the time is localized to GMT-8. It's a bit inconvenient because we really just want to keep the time in UTC.

of course this issue is amplified further at the date-picker directive because now we have no way to operate only in specific timezone other than the timezone set in the user's computer.

[pkozlowski-opensource]

@porschelau correct me if I'm wrong but if I'm reading you correctly you would like the date filter to output UTC values when "stringifing" a Date object?

[porschelau-old]

@pkozlowski-opensource I am proposing that we make the conversion to local time optional because the date filter does it all the time when you pass in an ISO8601 time string with TZ defined.

[pkozlowski-opensource]

@porschelau yes, it would be technically possible, although I'm not sure it makes sense for core... Marking as a feature request.

[porschelau-old]

The current implementation based the localization decision on the detection of the character Z or +/- in the time string. If we move that decision into a control parameter, it might benefit the module in terms of overall. It could be beneficial to the core. Can i help with this ticket?

[pkozlowski-opensource]

I'm not sure it should be solved on the string parsing part. Personally I would find it confusing if ISO string representing a string with a time-zone would be parsed as being in another time zone. This is why I think it should be rather solved on the formatting side.

[porschelau-old]

https://github.com/angular/angular.js/blob/master/src/ng/filter/filters.js#L359

that's the parse routine that runs when we push data into the filter. The fundamental question really is whether it is correct to parse the time to local time at L359?

[pkozlowski-opensource]

@porschelau this is parsing of a string to a Date object and it will parse it to a Date in the local time zone

If no timezone is specified in the string input, the time is considered to be in the local timezone.
http://docs.angularjs.org/api/ng/filter/date

After this parsing step you are ending up with a JavaScript Date object that will respond with values in the local time zone to method calls like getHours() etc. So the conversion to a local time zone doesn't happen when parsing but while formatting.