Hi, Scott-
This is certainly a valid aspect of Widgets... as a platform for a
specific kind of Web application: a collaboration/discussion/sharing app.
But it seems to me that this is conflating two orthogonal things: an
application host environment, and a collaboration platform. Widgets can
host the full range of Web apps; and a collaboration platform shouldn't
be confined to Widgets.
The context for a Widget, in my opinion, shouldn't inherently contain
the users of that Widget; that is functionality that should be specific
to collaboration apps.
As an analogy, think of the Geolocation API. A recipe widget which
finds recipes based on a list of available ingredients has no use for
that API, but a shopping widget might; traditional web sites built to do
those things would have the same needs. So, the Geolocation API is much
better off as a standalone API that is available when needed, and not
imposed when not needed, as general functionality, not just for Widgets.
It also seems that it would require more than just an API... it needs an
infrastructure from which to draw the relationship data, and security
considerations. Like the Geolocation API encapsulates underlying
device/service functionality (GPS, cell/wifi triangulation, logged IP
locations, etc.), and the Widget Interface's Storage API uses
functionality defined elsewhere (LocalStorage, SessionStorage,
IndexedDB, WebDB, remote web service), a Social API would have to rely
upon some source of data, which is not inherent in the device or a
single established web service, so that would need to be defined.
I don't think the WebApps WG is the right place to work on a Social API;
I don't think it would get the specific interest such an API would
require to do it right, with the current participants of this group
(though others in the group should correct me if I'm wrong). Also, the
WebApps WG has an urgent need to renew its charter to bring in
deliverables we've already agreed are in scope, so I would be extremely
reluctant to bring in a deliverable at this stage that has as broad a
scope as a Social API.
That's not to say a Social API is not useful or desirable. I'd love to
see this done at W3C, and I think it's important to make sure it works
well in both web sites and widgets. So, my counterproposal is to
suggest that you work with Harry Halpin to propose a new Social API WG
(maybe under Interaction Domain, but more fittingly under the Technology
and Society Domain), and bring in the Google Wave and Open Social folks
(since Google is already a W3C member), and find other stakeholders
(Facebook?) who might also be interested, to help standardize what they
have all already done. Harry and I have talked a bit before about next
steps for the Social Web, and this strikes me as a logical and pragmatic
next step. I will be happy to do what I can to help set this up, and to
ensure good communication between our groups, and to make sure that it
works well with Widgets.
Regards-
-Doug Schepers
W3C Team Contact, SVG and WebApps WGs
Scott Wilson wrote (on 2/13/10 5:21 AM):
Hi Doug,
I'm not adamant that these requirements are met specifically just for
Widgets, just that these are where the current use-cases come from. They
certainly ought to be supported through more general technologies where
possible.
There is also the issue of abstraction; should a widget author be
looking at low-level APIs to deliver functionality, or call a common
high-level API which is then implemented in a
device/architecture-specific way? E.g. if a widget author script wants
to get the list of current participants, should it need to be rewritten
for every platform it might be deployed in (e.g. XHR in some, Web
Sockets in another, native code another...) or can it call
"widget.getParticipants()" and let the UA handle the implementation?
Just as, for example, the Widget Interface defines "preferences" using
the Storage API: the actual choice of implementation of this
(LocalStorage, SessionStorage, IndexedDB, WebDB, remote web service) is
up to the UA.
So what I'm talking about here, just to be clear, are the high level API
abstractions available to a running widget (and potentially other types
of web application) and not any underlying protocols used to implement
them.
The specific high-level APIs I'm interested in are:
1. Participants [1]: getParticipants, getViewer, getOwner,
setParticipantCallback
2. State [1]: getState, state.submitDelta, state.submitValue,
setStateCallback
3. Friends/People [2]: getViewerFriends, getOwnerFriends
(Note these are subsets of the functionality of the referenced
specifications; other functionality they specify is already covered by
other W3C work such as Widgets:TWI [3] and Widgets:VMMF[4])
In some cases these APIs could map onto DAP (e.g. getViewer would map to
a call on the Contacts API) but in other cases would rely on other kinds
of implementations (OpenSocial itself, XHR, Websockets, Widget Feature
extensions etc). The principle interoperability being addressed would be
a consistent runtime model for a widget author irrespective of
deployment environment.
Widgets P&C already has a Feature extension mechanism for handling
availability of additional APIs that would be well suited to negotiating
availability of these types of APIs [5]. Apache Wookie already
implements Widgets P&C with a subset of the Google Wave Gadget API in
this fashion [6].
S
[1] http://code.google.com/apis/wave/extensions/gadgets/reference.html
[2]
http://wiki.opensocial.org/index.php?title=OSAPI_Specification#osapi.people
[3] http://www.w3.org/TR/widgets-apis/
[4] http://www.w3.org/TR/2009/WD-widgets-vmmf-20091006/
[5] http://www.w3.org/TR/widgets/#the-feature-element
[6] http://incubator.apache.org/wookie/
On 12 Feb 2010, at 23:50, Doug Schepers wrote:
Hi, Scott-
I'm still confused as to what you're asking for as a chartered
deliverable for Widgets.
Like others, I am extremely reluctant to define any special
functionality for Widgets, when it could be useful for Web
applications at large. Let me try to break down some of what you are
asking for in terms of specs we are already doing:
* communication between different widgets on the same computer: Web
Messaging [1]
* communication between widgets on different computers: Web Sockets
API [2], XHR [3] (through a gateway server)
* access to contacts on a specific device: Contacts API (DAP WG) [4]
* access to relationships between contacts, etc.: no current work, but
possible as an online service (XHR), or locally through markup like
RDFa or microdata
I don't know what social APIs OpenSocial or Google Wave Gadget API
expose, but anything above and beyond the deliverables listed above
should probably be developed by another group (maybe in collaboration
with the RDFa WG, since it probably has to do with ontologies?), and
simply reused within Widgets or Web apps.
But maybe I missed your point... can you give me a concise outline of
what the specific use cases and requirements you have for this social
API are?
[1] http://dev.w3.org/html5/postmsg/
[2] http://dev.w3.org/html5/websockets/
[3] http://dev.w3.org/2006/webapi/XMLHttpRequest/
[4] http://dev.w3.org/2009/dap/contacts/
Regards-
-Doug Schepers
W3C Team Contact, SVG and WebApps WGs
Scott Wilson wrote (on 2/12/10 5:39 PM):
Specifically I'm thinking of access to friends/friends-of lists from
author scripts in a Widget runtime. This is something of interest to
widget developers, as it enables widgets to operate as social
applications.
OpenSocial is an obvious source of inspiration here - however the actual
social APIs are only a small part of OpenSocial (which also covers all
aspects of app packaging. processing. discovery and persistence) and are
not easily reused in other kinds of devices and architectures.
The interop problem arises as currently authors of apps/widgets are
basically faced with two completely different "stacks" of specifications
based on the presence or absence of a few very small features - and the
"friends" API represents the main feature gap between the W3C widgets
family of specifications and OpenSocial.
Looking at recent developments, e.g. Vodafone's recent work on
integrating phone contacts and social network contacts, suggests that it
will not only be web widgets that would be able to access this type of
API, but also mobile and desktop widgets.
I would propose looking at this area with the W3C Social Web XG and
identifying a set of spec requirements either for webapps or DAP (it
could go either way - social APIs may fit better in DAP as they have
analogues with the contacts API work there, however Widgets are the
obvious vehicle for making use of such APIs. In any case some
co-ordination would be useful).
Currently in Apache Wookie we implement the Google Wave Gadget API as a
means of supporting inter-widget communication in collaboration
scenarios (e.g. multi-user environments); however the fact that this API
is completely different in almost every respect from the Google API to
get at friends (as opposed to participants) indicates there is a
significant interop gap where W3C could make a difference.
(One way of looking at this is that requesta for "contacts",
"participants" and "friends" are just differently contextualized queries
on a core "people API" and should behave consistently.)
