RFC 9557: Date and Time on the Internet: Timestamps with Additional Information
1–10 of 26 posts
Re: RFC 9557: Date and Time on the Internet: Timestamps with Additional Information
#2This does two things:
1.) Add an alternate way of specifying the time zone, which is possibly inconsistent with the time zone already specified in the time stamp, so there are multiple ways this might or might not be handled. Roughly 1/3 of the RFC seems to deal with that.
As the RFC tries to avoid saying: Do not use RFC9557/IXDTFs under any circumstance for any kind of information which will be used for security purposes; implementations will disagree what time stamp an IXDTF represents.
2.) Saying which calendar the time stamp actually refers to.
This does not provide a way to fix the "I'm actually referring to a fixed calendaric event and if the time zone changes, I don't want that event to shift" problem.
Re: RFC 9557: Date and Time on the Internet: Timestamps with Additional Information
#3This is a valiant attempt at resolving an extraordinarily difficult problem, but it falls far too short. Just as an example, I am very happy to see that they address alternative calendars such as Arabic and Hebrew calendars. But they only address representing specific points in time as Gregorian dates, and then suggesting to alternate
-calendar-aware applications that these specific Gregorian dates should be shown in this alternate calendar. This does not enable, eg, setting somebody's birthday as 18th of Tishre and having the calendar show an alert every year. Nor does it allow setting a date on e.g. 25th of Shaaban, considering that we don't yet know on which day the 25th of Shaaban will fall on the Gregorian calendar.
The only real problems that this RFC solves, are problems that have already been solved in extensions to ISO 8601, for example in popular Java libraries.
Re: RFC 9557: Date and Time on the Internet: Timestamps with Additional Information
#4I don't really like it?
Adding a human readable timezone string in addition to the existing numerical offset is just creating opportunities for inconsistencies between the numerical and string values. Now there is extra special syntax for whether the application MUST act on detected inconsistencies, or whether it's safe to ignore it. Better to avoid defining an inconsistent format in the first place.
Projecting the timestamp into a specific calendar seems more like a localization problem than something that should be specified in the timestamp itself.
Adding support to bundle custom metadata key:value pairs into timestamp strings also seems misguided? Let timestamps be timestamps, if you need a more use a proper type instead of passing around timestamp strings.
edit: I can see the reasoning for the proposal, but I think it just doesn't get there. On the one hand it adds some confusing complexity to what is otherwise a very simple format to deal with. On the other, it's clearly not going to be sufficient for developers of complex non-gregorian/multi-calendar applications.
Re: RFC 9557: Date and Time on the Internet: Timestamps with Additional Information
#5I feel like they are making a massive mistake by allowing UTC offset in the ISO8601 part of the timestamp. They try to extend the existing format in a seemingly backwards-compatible way, but ignore the fact that the existing format is fundamentally broken.
A stamp like "2022-07-08T00:14:07+01:00[Europe/Paris]" should never be a thing. It's invalid. Downstream code can treat it as either "+01:00" or "Europe/Paris" (which at that point is on +2:00), so you are begging for data corruption. The whole concept of "inconsistent timestamps" should not exist!
The "2022-07-08T00:14:07Z[Europe/London]" for "convert this UTC timestamp to whatever that happens to be in local time" part is probably a mistake as well, because it's going to seduce less careful developers to store timestamps as UTC. If it's a fixed point in time which can be stored as UTC, it shouldn't need a timezone: just let the frontend convert it to whatever timezone the user prefers. If it's a local timestamp, it shouldn't be stored in UTC in the first place.
It would make a lot more sense to just stick to "2022-07-08T00:14:07[Europe/Paris]" local time + named timezone format, without a numeric UTC offset. If your application doesn't support the timezone tag, it cannot parse it and it cannot meaningfully make use of it. End of story. Want to store a fixed point in time, for something like logging? Stick with "2022-07-08T00:14:07Z".
Re: RFC 9557: Date and Time on the Internet: Timestamps with Additional Information
#6[deleted]
Re: RFC 9557: Date and Time on the Internet: Timestamps with Additional Information
#7I feel like they are making a massive mistake by allowing UTC offset in the ISO8601 part of the timestamp. They try to extend the existing format in a seemingly backwards-compatible way, but ignore the fact that the existing format is fundamentally broken . A stamp like "2022-07-08T00:14:07+01:00[Europe/Paris]" should never be a thing. It's invalid. Downstream code can treat it as either "+01:00" or "Europe/Paris" (w…
[deleted]
Re: RFC 9557: Date and Time on the Internet: Timestamps with Additional Information
#8Related: https://tc39.es/proposal-temporal/
> This specification benefits from work prepared by ECMA TC39, specifically in the Temporal proposal.
Implementations: https://github.com/tc39/proposal-temporal/tree/main/?tab=rea...
Re: RFC 9557: Date and Time on the Internet: Timestamps with Additional Information
#9Can anybody explain why we should just not do what unix and gps do and use an agreed upon epoch, and let all the front ends make the conversions?
I genuinely dread human readable timestamps inside backend code and always use unix time. Even in front end adding the whole human readable time stamp takes almost 60 characters out of the logs.
I often look at timestamps in human format and wonder what time zone is this, and does the computer even have a synced clock. A week ago I debugged a 2FA issue where one intervenient did not have NTP configured and the clock was off by some random 20 minutes, and thus tokens were emitted expired.
Re: RFC 9557: Date and Time on the Internet: Timestamps with Additional Information
#10It is somewhat ironic that the date reference in use throughout that page is of the form "April 1987”.
I greatly respect the effort to make a well-thought-out timestamp that balances readability and cultural neutrality and versatility across contexts and eras. I try to use at least ISO–8601 timestamps when I can.
It sometimes feels like a losing battle though. Even if a luser can roughly guess what
1996-12-19T16:39:57-08:00[America/Los_Angeles]
I don't know what the answer is here. Maybe a "time reference" object that your interface can interpret dynamically to your preferences and needs?