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(1) Server → Client: RFC 3339
| The server should send RFC 3339 formatted dates to the client.. |
The server should send UTC dates formatted as RFC 3339 to the client. Eg. "2021-01-29T13:51:03Z" .
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(2) Client → Server: ISO 8601
| The client should sent ISO 8601 formatted dates to the server. |
The client should send dates to the server that are formatted with ISO 8601 such that date, time and time zone information are always available.
Eg. "2021-01-29T16:51:03+03:00".
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(3) Client Display: In Local Time Zone
| The client should display dates in the local time zone of the user. |
The client should parse RFC 3339 formatted dates to make it readable and useful to the user. In almost all circumstances users should see dates that are local to them, in accordance to their client or local system's time zone.
This is very straightforward to do in JavaScript as this just works with a RFC 3339 formatted date:
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