Format date properties

[schiwekM]

Hi colleagues,

currently if a cds.Date property is modified it is shown as '2022-12-01' in the change log. This is not really user friendly and thus this PR adds date formatting so the dates show up as they would in UI5, e.g. '01 Dec 2022'

BR,
Marten

[schiwekM]

@Sv7enNowitzki could this one be considered too? Would be great to have it for improved UX, because business users at not to used to the ISO format for dates.

[nkaputnik]

Hello Marten, I have to reject this PR.
Change log Dates are indeed meant to be technical, and require to be e.g. sortable and searchable.
The use cases we encounter frequently are, that the change logs aren't even shown with the built-in UI facet, but rather in a separate, dedicated change-log UI. Since the format is statically determined at write-time, and not dynamically when reading, localizing what was written is not a good idea, especially when searching for a specific date in the logs by users in different locales.

[schiwekM]

Hi Nik, I just checked again and the logic is only run in an after READ handler on ChangeView so on DB it is as intended still in ISO format.

[danjoa]

Usually such formatting is applied on the UI, not on the API / the protocol.
I assume the problem here is that these values are intermixed with other non-date values?

[schiwekM]

Usually such formatting is applied on the UI, not on the API / the protocol. I assume the problem here is that these values are intermixed with other non-date values?

Yes. The problem is that in the metadata the field is marked as a string field and thus taken by FE as is. It could also be solved if CAP would send valueChangedTo@type and valueChangedFrom@type in the result set with the EDM type to apply and UI5/FE would interpret this dynamic type accordingly for formatting.

[nkaputnik]

Hello @schiwekM
that second proposal from you seems much more sensible to me. I'm hesitant to do any string manipulation in the backend, an annotation to instruct the front-end is much better. Any chance that you could do this yourself and submit in this PR?

Best,
Nick

[danjoa]

Agreed, that sounds reasonable