13929 2011-08-28 14:44:57 +0000 The microdata vCard and vEvent vocabularies support global identifiers, but the RFC UID formats are invalid URLs 2011-10-25 08:38:17 +0000 1 1 1 Unclassified HTML WG HTML Microdata (editor: Ian Hickson) unspecified Other other RESOLVED FIXED http://www.whatwg.org/specs/web-apps/current-work/#vcard P3 normal --- 1 contributor ian ian jeni julian.reschke mike philipj public-html-admin public-html-wg-issue-tracking w3.org public-html-bugzilla oldest_to_newest 55919 0 contributor 2011-08-28 14:44:57 +0000 Specification: http://www.whatwg.org/specs/web-apps/current-work/complete/microdata.html Multipage: http://www.whatwg.org/C#vcard Complete: http://www.whatwg.org/c#vcard Comment: The microdata vCard and vEvent vocabularies support global identifiers, but the RFC UID formats are invalid URLs Posted from: 125.175.150.1 by w3.org@boblet.net User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_6_8) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/13.0.782.112 Safari/535.1 55920 1 w3.org 2011-08-28 15:04:19 +0000 itemids must be valid URLs, however the spec example microdata vocabularies give no guidance to valid global identifiers. The example UIDs listed in the referred RFCs also don’t appear to be one of the IANA URI schemes, eg: “The type can include the type parameter "TYPE" to specify the format of the identifier. The TYPE parameter value should be an IANA registered identifier format. The value can also be a non-standard format. Type example: UID:19950401-080045-40000F192713-0052” http://tools.ietf.org/html/rfc2426#section-3.6.7 “Property Parameters: Non-standard property parameters can be specified on this property. Description: The UID itself MUST be a globally unique identifier. The generator of the identifier MUST guarantee that the identifier is unique. There are several algorithms that can be used to accomplish this. The identifier is RECOMMENDED to be the identical syntax to the [RFC 822] addr-spec. Example: The following is an example of this property: UID:19960401T080045Z-4000F192713-0052@host1.com” http://tools.ietf.org/html/rfc2445#section-4.8.4.7 As itemid is entirely up to the vocabulary it’d help ppl to understand itemid usage if these specs were clear about what global identifiers are valid, ideally with an example using a global identifier. This would also help vocabulary writers (schema.org) to clearly define global identifiers — http://schema.org/Book only defines ISBN as an itemprop currently. Ref: http://www.w3.org/Bugs/Public/show_bug.cgi?id=13452 http://microformats.org/wiki/vcard-errata#3.6.7_UID_Type_Definition http://www.iana.org/assignments/uri-schemes.html 58298 2 ian 2011-10-17 19:25:19 +0000 So there's two ways we can go with this: - make itemid="" any arbitrary string, with vocabularies defining the precise requirements on uniqueness and syntax - make the vCard and vEvent vocabs not use itemid="". I think I'm leaning towards the second. The problem with the first is that it might encourage people to use itemid="" for things like ISBN number, which would lead them to difficulties if they decide their items aren't exactly one publication, so for example a hard cover edition and paperback edition would have the same item. 58833 3 ian 2011-10-25 03:05:59 +0000 EDITOR'S RESPONSE: This is an Editor's Response to your comment. If you are satisfied with this response, please change the state of this bug to CLOSED. If you have additional information and would like the editor to reconsider, please reopen this bug. If you would like to escalate the issue to the full HTML Working Group, please add the TrackerRequest keyword to this bug, and suggest title and text for the tracker issue; or you may create a tracker issue yourself, if you are able to do so. For more details, see this document: http://dev.w3.org/html5/decision-policy/decision-policy.html Status: Accepted Change Description: see diff given below Rationale: Concurred with reporter's comments. 58834 4 contributor 2011-10-25 03:06:07 +0000 Checked in as WHATWG revision r6746. Check-in comment: Change the vCard and vEvent vocabs to not use itemid='' since their UIDs aren't URLs. http://html5.org/tools/web-apps-tracker?from=6745&to=6746 58897 5 philipj 2011-10-25 08:38:17 +0000 So now there are no known vocabularies using itemid... Wouldn't it be just as good to drop the attribute entirely and let vocabularies that need something like this define a property themselves? Schema.org has the url property which is likely to often overlap with itemid, should they ever get around to defining what it means (http://www.w3.org/2011/webschema/track/issues/6).