Machine tags for activity streams

[Chris Messina]

I mentioned my machine tag idea on an earlier thread:

http://groups.google.com/group/activity-streams/browse_thread/thread/d9c8c0d710fc8b1b

I wanted to bring it up again because Flickr has a post that describes the power of machine tags:

http://code.flickr.com/blog/2008/12/15/machine-tag-hierarchies/

They link to another post that I think is useful to consider:

http://code.flickr.com/blog/2008/07/18/wildcard-machine-tag-urls/

What's most interesting here is that if we start publishing activity machine tags, we could quickly build a Flickr-style API on top of it:

http://www.flickr.com/services/api/flickr.machinetags.getNamespaces.html

http://www.flickr.com/services/api/flickr.machinetags.getPredicates.html

http://www.flickr.com/services/api/flickr.machinetags.getValues.html

http://www.flickr.com/services/api/flickr.machinetags.getPairs.html

And, for an example of how this can manifest itself, check this out:

http://husk.org/code/machine-tag-browser.html

Now imagine being able to consume FriendFeed in an experience like that...!

The crux of this proposal is the identify actors, verbs and objects in ATOM categories, like so:

    <category term="activity:actor=factoryjoe" scheme="http://activitystrea.ms/schema/1.0/"/>

    <category term="activity:object-type=photo" scheme="http://activitystrea.ms/schema/1.0/"/>

    <category term="activity:verb=post" scheme="http://activitystrea.ms/schema/1.0/"/>

or in RSS, like this:

<media:category scheme="http://activitystrea.ms/schema/1.0/"> activity:actor=factoryjoe activity:object-type=photo activity:verb=post </media:category>

Chris

--
Chris Messina
Citizen-Participant &
 Open Technology Advocate-at-Large
factoryjoe.com # diso-project.org
citizenagency.com # vidoop.com
This email is:   [ ] bloggable    [X] ask first   [ ] private

[Chris Messina]

Hmm, interesting.

I guess the reason why I might push back on that, initially, is that feed consumers might have their own uses for machine tags (i.e. flickr, upcoming). Not that the scheme couldn't hint that the category should be interpreted as a machine tag, but I think there might be something lost from that approach... not sure.

Perhaps what you're suggesting is exactly how the scheme attribute of category tags are supposed to be used, in which case I'd like to hear from the Flickr folks what they think about that.

I can tell you that when I use custom machine tags on Flickr, they show up in my ATOM feed like this:

<category term="iusethis:app=imageoptim" scheme="http://www.flickr.com/photos/tags/" />

As for the point about actors, I tend to agree that full URLs would be more useful. I wonder, though, if we can make some kind of aesthetic optimization, where, if no base URL is provided for the actor, we could simply provide a category with an sgnodemapper-derived value?

<category term="factoryjoe" scheme="sgn://flickr.com/?ident" />

Not sure about that though.

Thanks for the feedback! Others?

Chris

On Thu, Dec 18, 2008 at 7:16 PM, NeilFred Picciotto <neil...@gmail.com> wrote:

One thought that occurs to me is that rather than cram all the data
into the term -- forcing the need for custom parsing logic -- why not
put the different classes of things into the scheme?  So your examples
would become:

   <category term="factoryjoe"
scheme="http://activitystrea.ms/schema/1.0/actor"/>
   <category term="photo"
scheme="http://activitystrea.ms/schema/1.0/object-type"/>
   <category term="post" scheme="http://activitystrea.ms/schema/1.0/verb"/>

Also, it feels like the "actor" (and in general, any person
identifier) should expect a URL.  (Could even use sgn:// URLs, as used
by the SocialGraph API, but maybe simpler to just use arbitrary http
URLs, and figure that consumers of the feeds can always use the
NodeMapper to convert things to sgn:// if that's useful to them...)

--
NeilFred Picciotto