ISSUE-76: CHANGE PROPOSAL: Separate Microdata from HTML5 Specification

The following document outlines a Change Proposal to remove Microdata
from the HTML5 specification. The document was created due to a request,
during the last HTML WG telecon, by one of the Chairs for HTML WG. This
e-mail is formatted to conform to step 2.b of the Escalation Process
section[1] of the HTML Working Group Decision Policy document.


There are currently two mechanisms under active development by the HTML
WG for embedding machine-readable semantics in HTML5 - RDFa and
Microdata. The HTML+RDFa spec was published in a separate document, as a
specification built on top of HTML5. The Microdata spec was published
inside of the HTML5 specification, while the discussion of whether or
not to include RDFa was still taking place.

While there are many points to be made for and against RDFa and
Microdata as technologies, this proposal is not concerned with those
arguments. Rather, this change proposal is concerned with the
ramifications of placing a new technology that has not gained broad
deployment experience nor authoring feedback into the main HTML5

Primarily, this Change Proposal asserts that RDFa barely meets the
requirement of broad deployment experience and authoring feedback.
Microdata, having achieved no deployment experience and very little
authoring feedback (to date), is still under active development.

This proposal argues that both RDFa and Microdata should be kept
separate from the HTML specification until it is clear to this Working
Group that they have become broadly deployed and heavily utilized by the
HTML authoring community. This has a number of benefits in the case that
either or both technologies do well, as well as in the case where both
technologies fail.

Separating both RDFa and Microdata from the HTML5 specification have
several significant advantages and no significant disadvantages.


There are a number of basic premises related to separating RDFa and
Microdata from the main HTML5 specification:

* Either RDFa or Microdata (or both) may fail in the marketplace.
* It is more productive for philosophically divergent communities
(RDFa/Microdata) within a larger community (HTML WG) to have their own
work products during a period of active debate. Those complete work
products should only be presented to the larger group for consensus when
they reach maturity.
* Both HTML+RDFa and HTML+Microdata should be allowed to become mature
drafts before consensus on inclusion or dismissal is discussed.
* Having the RDFa and Microdata specification separate from the HTML5
specification will allow those technologies to evolve independently from
HTML5 (during LC, and after REC).

A number of potential conclusions can be drawn from the premises and
current state of affairs:

* If either RDFa or Microdata fail in the marketplace in the long-term,
it would be advisable to allow either (or both) to fail without having a
negative impact on the HTML5 spec proper.
* The HTML+RDFa and HTML+Microdata drafts should be allowed to mature
until Last Call before one or both are selected for inclusion into
HTML5. A productive way to enable that maturation process is to separate
the concerns into separate documents.
* If we don't separate the documents into different work products, the
alternative is to argue over which work product to allow, which does not
lead to the production of a specification outlining each philosophy.
Worse, it may prevent a particular work product from being developed to
maturity before it is struck down.

Proposal Details

The change details of this proposal would require removing all language
discussing Microdata into a separate specification. It has been proven
that the Microdata specification can be cleanly migrated into a separate
HTML+Microdata specification:

The work to remove the Microdata language from the body of the HTML5
specification took roughly 8-10 hours for a single person to perform.


Negative Effects
* May produce less interest in and feedback on both RDFa and Microdata
since they are removed to separate, non-competing specifications.
* All Microdata attributes would be defined in a separate specification,
much like the RDFa attributes are in the HTML+RDFa spec.

Positive Effects
* Addresses the months-long Microdata vs. RDFa debate by employing the
"allowing many flowers to bloom" strategy instead of the "Mad Max"
strategy[2] that has been driving the debate.
* Demonstrate that multiple specs are capable of being layered on top of
* Allows RDFa and Microdata to organically mature at their own pace,
largely independently from HTML5.
* Allows RDFa or Microdata (or both) to fail without affecting the main
HTML5 specification.
* Changing both RDFa and Microdata in the future wouldn't require the
HTML5 specification to be republished as a REC (a very costly process).
* Frees the WHATWG and HTMLWG to concentrate on other religious debates
(like which editor is better for web development... emacs or vi). =P

-- manu


Manu Sporny (skype: msporny, twitter: manusporny)
President/CEO - Digital Bazaar, Inc.
blog: Establishing an Open Digital Media Commerce Standard

Received on Thursday, 22 October 2009 02:22:50 UTC