W3C home > Mailing lists > Public > public-device-apis@w3.org > August 2009

RE: Requirements gathering

From: Marcin Hanclik <Marcin.Hanclik@access-company.com>
Date: Wed, 26 Aug 2009 21:53:39 +0200
To: Robin Berjon <robin@robineko.com>, DAP <public-device-apis@w3.org>
Message-ID: <FAA1D89C5BAF1142A74AF116630A9F2C2890C65BC7@OBEEX01.obe.access-company.com>
Hi Robin,

I believe you already adhered to the BONDI APIs requirements:
that were pre-agreed by many participants of DAP.

Shall we define use cases as the integral part of the requirements?
What about having corresponding section by default?


Marcin Hanclik
ACCESS Systems Germany GmbH
Tel: +49-208-8290-6452  |  Fax: +49-208-8290-6465
Mobile: +49-163-8290-646
E-Mail: marcin.hanclik@access-company.com

-----Original Message-----
From: public-device-apis-request@w3.org [mailto:public-device-apis-request@w3.org] On Behalf Of Robin Berjon
Sent: Tuesday, August 25, 2009 3:52 PM
Subject: Requirements gathering

Dear all,

I think you may have noticed from the tracker spam that I have
requirements gathering for APIs on my mind!

I'd like to strike a balance whereby we do gather enough requirements
to give ourselves a rough idea of the area that each API should cover,
but without becoming too formal.

Where form is concerned, for each requirement I tend to think that a
simple, clear sentence should usually suffice (unless there is
dissent), if possible using an RFC 2119 keyword so that the result can
be evaluated against it. For example:

   The frobulator MUST expose a way to frobulate.
   The Math API MAY support additions, if we can solve the technical
issues involved.
   Solving the Halting Problem SHOULD NOT be supported for version 1.

One of my primary goals here is to limit feature creep, and to make it
possible to release simple APIs fast - and if there's more to do on a
given API there is nothing keeping us from publishing a v2 or v3
within the same charter that we have (we are limited in scope but not
in how many iterations we perform within that scope).

According to that, "MUST" does not mean "we want feature X" but rather
"if feature X is not included then we think that the API will be
completely unusable". "SHOULD" means "we really, really want it" as in
"we'd pay good money for it". "MAY" is for stuff that could get in if
it's really cheap and obvious, or that would be cool to consider for
the following version.

Be honest - it shows. And people who've shown to be honest get more
political sway down the line ;-)

Another important goal is deciding when to publish the first draft of
a given API (skip to the last sentence if talk of Patent Policy hurts
your brain). According to the W3C Patent Policy, the First Public
Working Draft (FPWD) starts an exclusion period during which people
can exclude patents from being licensed RF for implementations of that
specification - after the period has run out they are considered to be
in if they haven't excluded. Then, when the document reaches the Last
Call maturity level there is a second similar (but shorter) call for
exclusions, but it only applies to features that were not already
covered in the first one. To make a long story short: it is better if
the FPWD of a specification is feature-complete (even if the features
aren't perfectly defined).

Finally, I think that this will be easier than just comparing inputs,
which can be a needlessly bruising exercise for a young group. And
since people have already created APIs in all of the domains that we
are chartered to address I expect that they have already considered
requirements - which should make the process quick and hopefully

I would like to have rough consensus on this within a couple weeks, so
if you want your input to matter get writing now!

Robin Berjon
   robineko - setting new standards


Access Systems Germany GmbH
Essener Strasse 5  |  D-46047 Oberhausen
HRB 13548 Amtsgericht Duisburg
Geschaeftsfuehrer: Michel Piquemal, Tomonori Watanabe, Yusuke Kanda


This e-mail and any attachments hereto may contain information that is privileged or confidential, and is intended for use only by the
individual or entity to which it is addressed. Any disclosure, copying or distribution of the information by anyone else is strictly prohibited.
If you have received this document in error, please notify us promptly by responding to this e-mail. Thank you.
Received on Wednesday, 26 August 2009 19:54:33 UTC

This archive was generated by hypermail 2.3.1 : Monday, 23 October 2017 14:53:38 UTC