Comments on: Apple’s iCal and iCal/vCal format http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format Helping companies with marketing, product strategy, user experience design, and technology development. Thu, 22 Jul 2010 15:01:08 +0000 hourly 1 http://wordpress.org/?v=3.0 By: Mark Treveil http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format/comment-page-1#comment-9628 Mark Treveil Tue, 08 Jun 2010 21:58:56 +0000 http://blog.davidcrow.ca/?p=173#comment-9628 One observation: you have dates with both a time zone AND ending in a "Z". I think you;ll find that "Z" means UTC, so you can't use this with a TimeZone One observation: you have dates with both a time zone AND ending in a “Z”. I think you;ll find that “Z” means UTC, so you can't use this with a TimeZone

]]> By: David Crow http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format/comment-page-1#comment-160 David Crow Fri, 25 Mar 2005 23:43:19 +0000 http://blog.davidcrow.ca/?p=173#comment-160 <p>George, you hit it on the head, iCal is really picky about the extra spaces in the code. I had to make sure to trim any extra white spaces.</p> George, you hit it on the head, iCal is really picky about the extra spaces in the code. I had to make sure to trim any extra white spaces.

]]> By: George Paci http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format/comment-page-1#comment-162 George Paci Thu, 24 Mar 2005 22:07:57 +0000 http://blog.davidcrow.ca/?p=173#comment-162 <p>Warning: horribly off-topic Sorry, but I couldn't find your email anywhere. This is in response to your July 6, 2004 posting about problems with iCal. I noticed that your vCalendar text, as it appeared on the site, had trailing spaces on some begin/end lines. When I fed it to iCal, it didn't like that at all, and essentially ignored all events that had the problem. This pickiness may be the entire problem. Please let me know if this was helpful.</p> Warning: horribly off-topic

Sorry, but I couldn’t find your email anywhere. This is in response to your July 6, 2004 posting about problems with iCal.

I noticed that your vCalendar text, as it appeared on the site, had trailing spaces on some begin/end lines. When I fed it to iCal, it didn’t like that at all, and essentially ignored all events that had the problem.

This pickiness may be the entire problem. Please let me know if this was helpful.

]]> By: David Crow http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format/comment-page-1#comment-101 David Crow Mon, 19 Jul 2004 14:14:43 +0000 http://blog.davidcrow.ca/?p=173#comment-101 <p>It looks like the error is with the <a href="http://www.apple.com/ical/">iCal</a> parser and the extra space after each <pre>END:VEVENT </pre> as Olivier suggests. I wish that <a href="http://www.apple.com/ical/">iCal</a> was a little more liberal in parsing. This seems to be a common debate for <a href="http://diveintomark.org/archives/2004/01/08/postels-law">RDF</a>, <a href="http://essaysfromexodus.scripting.com/postelsLaw">RSS</a> and <a href="http://www.tbray.org/ongoing/When/200x/2004/01/11/PostelPilgrim">Atom</a> <a href="http://inessential.com/?comments=1&postid=2604">feed parsing</a>. </p> It looks like the error is with the iCal parser and the extra space after each 
END:VEVENT 

as Olivier suggests. I wish that iCal was a little more liberal in parsing. This seems to be a common debate for RDF, RSS and Atom feed parsing.

]]> By: bex http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format/comment-page-1#comment-122 bex Fri, 16 Jul 2004 18:11:07 +0000 http://blog.davidcrow.ca/?p=173#comment-122 <p>Actually I found the error. The ics files are autogenerated by perl code that parses the pub 509 html from the IRS. There is one entry that is irregular and was resulting in a date of 20040000. This caused the entire month of January to be unhappy, only in Month display mode. All other months and display modes were ok. I corrected it and the world is good! As an aside: Does anyone find this idea useful? An intermediary that sits between your ical and a subscribed calendar and edits it. Here are three examples uses that I have come up with (I don't do all of these personally): 1 - Eliminate certain holidays in a calendar (i.e. eliminate Labor Day from the US Holidays calendar because I must labor on that day. Or, eliminate certain holidays from a religious calendar because I don't celebrate them. 2 - Eliminate all "away" games from a sports calendar because I only care about the team enough to follow them at home (or I just want a calendar of season ticket opps). 3 - In the case of my Tax calendars, one of them provides info on both Payroll and Nonpayroll based withholdings. I only care about payroll based withholdings, so I scrub the others out. I have this running personally, and am not sure whether I should clean up for release. comments? PS: To David Crow: I apologize for hijacking your comments section of your blog like this. Please delete this post with my apologies if it is inappropriate. While I am a very seasoned internet user, I really do not follow the blog scene and so I am less aware of the netiquette.</p> Actually I found the error. The ics files are autogenerated by perl code that parses the pub 509 html from the IRS. There is one entry that is irregular and was resulting in a date of 20040000. This caused the entire month of January to be unhappy, only in Month display mode. All other months and display modes were ok. I corrected it and the world is good!

As an aside: Does anyone find this idea useful?

An intermediary that sits between your ical and a subscribed calendar and edits it. Here are three examples uses that I have come up with (I don’t do all of these personally):

1 – Eliminate certain holidays in a calendar (i.e. eliminate Labor Day from the US Holidays calendar because I must labor on that day. Or, eliminate certain holidays from a religious calendar because I don’t celebrate them.

2 – Eliminate all “away” games from a sports calendar because I only care about the team enough to follow them at home (or I just want a calendar of season ticket opps).

3 – In the case of my Tax calendars, one of them provides info on both Payroll and Nonpayroll based withholdings. I only care about payroll based withholdings, so I scrub the others out.

I have this running personally, and am not sure whether I should clean up for release.

comments?

PS: To David Crow: I apologize for hijacking your comments section of your blog like this. Please delete this post with my apologies if it is inappropriate. While I am a very seasoned internet user, I really do not follow the blog scene and so I am less aware of the netiquette.

]]> By: Olivier Gutknecht http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format/comment-page-1#comment-102 Olivier Gutknecht Thu, 15 Jul 2004 14:30:48 +0000 http://blog.davidcrow.ca/?p=173#comment-102 <p>Do you have any online example of such a faulty calendar file, bex ? The iCalendar RFC is quite complex, and it's easy to make a minor mistake.</p> Do you have any online example of such a faulty calendar file, bex ? The iCalendar RFC is quite complex, and it’s easy to make a minor mistake.

]]> By: bex http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format/comment-page-1#comment-86 bex Wed, 14 Jul 2004 07:41:54 +0000 http://blog.davidcrow.ca/?p=173#comment-86 <p>I have run into a similar problem. Some homebrew ics files appear to display all events except those occurring in January 2004 in iCal. Oddly, they prevent all calendar's events from showing in that month. If you drill down to the day or week view, the events are there (they are all all-day events). If you deselect this calendar, then the other calendar's events will reappear. But only until you deselect/select them. I can find nothing different about the way I generated the January versus the other month events. Have you found out more about this problem on your end? danke</p> I have run into a similar problem. Some homebrew ics files appear to display all events except those occurring in January 2004 in iCal. Oddly, they prevent all calendar’s events from showing in that month. If you drill down to the day or week view, the events are there (they are all all-day events). If you deselect this calendar, then the other calendar’s events will reappear. But only until you deselect/select them.

I can find nothing different about the way I generated the January versus the other month events. Have you found out more about this problem on your end?

danke

]]> By: David Crow http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format/comment-page-1#comment-110 David Crow Fri, 09 Jul 2004 19:43:38 +0000 http://blog.davidcrow.ca/?p=173#comment-110 <p>I could have sworn that NAME: was part of the spec. Thanks Tim, you are correct that it is not in there at all. I'll expose the .ics tonight. It is running on a development server which is behind the firewall. Either I'll promote to test, or just copy the file up.</p> I could have sworn that NAME: was part of the spec. Thanks Tim, you are correct that it is not in there at all.

I’ll expose the .ics tonight. It is running on a development server which is behind the firewall. Either I’ll promote to test, or just copy the file up.

]]> By: Tim http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format/comment-page-1#comment-121 Tim Fri, 09 Jul 2004 19:15:42 +0000 http://blog.davidcrow.ca/?p=173#comment-121 <p>I've posted a draft (note: version 00 so there will be some typos) on some guidelines for XML and iCalendar use.. this is an individual draft, but if you decide to look into XML and iCal I'd like to hear your opinions. http://www.ietf.org/internet-drafts/draft-hare-xcalendar-00.txt One thing I saw in your file that isn't in the standard (RFC2445) is the NAME: property of VCALENDAR. Not sure if that causes a problem in iCal but it definitely seems non-stanard-compliant</p> I’ve posted a draft (note: version 00 so there will be some typos) on some guidelines for XML and iCalendar use.. this is an individual draft, but if you decide to look into XML and iCal I’d like to hear your opinions.

http://www.ietf.org/internet-drafts/draft-hare-xcalendar-00.txt

One thing I saw in your file that isn’t in the standard (RFC2445) is the NAME: property of VCALENDAR. Not sure if that causes a problem in iCal but it definitely seems non-stanard-compliant

]]> By: Olivier Gutknecht http://davidcrow.ca/article/641/apples-ical-and-icalvcal-format/comment-page-1#comment-120 Olivier Gutknecht Fri, 09 Jul 2004 17:18:37 +0000 http://blog.davidcrow.ca/?p=173#comment-120 <p>It basically works for me in iCal 1.5.2 too (at least for two events). For the three others, there are some problems in the ICS pasted here, that is some of the "BEGIN:EVENT" / "END:EVENT" like do have an extra space after the EVENT string, which is sufficient to have them not recognized as a VEVENT component (the iCal parser seems to be ultra-strict here). This can be also due to a problem when pasting the ics content here, an URL to the actual file would be necessary to have a definitive advice on that.</p> It basically works for me in iCal 1.5.2 too (at least for two events). For the three others, there are some problems in the ICS pasted here, that is some of the “BEGIN:EVENT” / “END:EVENT” like do have an extra space after the EVENT string, which is sufficient to have them not recognized as a VEVENT component (the iCal parser seems to be ultra-strict here). This can be also due to a problem when pasting the ics content here, an URL to the actual file would be necessary to have a definitive advice on that.

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