Salmon as a protocol for pushing activities around

[Martin Atkins]

Hi all,

Last weekend I started work on what I intended to be "the simplest thing
that could possibly work" to push activities from a social site to an
identity hub.

My early draft is here:
http://martin.atkins.me.uk/specs/activitystreams/activitypush

It wasn't until the Salmon security session at IIW yesterday that I
realized that these two things are really the same. What Salmon adds
compared to my spec is an ad-hoc authentication mechanism. I declared
specific authentication mechanisms to be out of scope, preferring to
focus on how the activity itself would be transported, but
authentication is an important piece.

It feels like these efforts should definitely be unified. I'm happy to
yield to John's Salmon spec since it is further along than mine, but I
thought it'd be useful to start a conversation about what an activity
push protocol might look like.

The requirements I started with are:

* Should be as compatible as possible with the activity submission
endpoint provided by OpenSocial providers, assuming that OpenSocial has
already been extended to support Activity Streams.

* Should support the decentralization of my "activity stream provider"
from the social sites I use to generate activities.

I think Salmon adds an additional one:

* Should support pushing relevant activities *between* social sites
when activities cross site boundaries, such as leaving a comment on
FriendFeed to an item from Flickr, or clicking "Like" on Facebook on a
blog entry that came from TypePad.