SData or SakaiData (the name is loosely based of GData) is just a normal webapplication (https://source.sakaiproject.org/contrib/tfd/trunk/sdata/) which will be used to feed out data about Sakai to the client side of the project. SData is like a REST based webservice that will return specific data according to the URL you have asked for. In this way, we can keep a clear distinction between data services and implementation. In the longer term, we want to build up a good set of services that return useful information that can be used/combined in any kind of tool/widget/… Data can be fed out as XML or JSON (We’ve got both implementations), but in our development we are only using the JSON ones, because of the speed and ease of use.

Some examples of SData are:

* Message of the Day: if you do a GET request to /sdata/motd you’ll get back :

{"items":[{"motdBody":"<p>This is the message of the day!<\/p>\r\n\r\n
<p>Dit is de boodschap van de dag!<\/p>","motdUrl":"http://celestine.c
aret.local:8080/access/announcement/msg/!site/motd/c1416055-1b9c-4ba2-
8d3a-442c585203da"}]}

* List of my Courses and Projects: if you do a GET request to /sdata/mcp you’ll get back :

{"items":[{"iconUrl":null,"title":"Administration Workspace","owner":
"Sakai Administrator","members":1,"description":"Administration Works
pace","creationDate":"04-12-2007","url":"http://moonstone.caret.local
:8080/portal/site/~admin","siteType":null,"id":"~admin"},{"iconUrl":n
ull,"title":"Administration Workspace","owner":"Sakai Administrator",
"members":1,"description":"Administration Workspace","creationDate":"
04-12-2007","url":"http://moonstone.caret.local:8080/portal/site/!adm
in","siteType":null,"id":"!admin"},{"iconUrl":null,"title":"AnncTest"
,"owner":"Sakai Administrator","members":1,"description":"AnncTest","
creationDate":"29-02-2008","url":"http://moonstone.caret.local:8080/p
ortal/site/AnncTest","siteType":null,"id":"AnncTest"},{"iconUrl":null
,"title":"filemanager","owner":"Sakai Administrator","members":3,"des
cription":"filemanager","creationDate":"06-03-2008","url":"http://moo
nstone.caret.local:8080/portal/site/filemanager","siteType":null,"id"
:"filemanager"},{"iconUrl":null,"title":"mercury site","owner":"Sakai
Administrator","members":3,"description":null,"creationDate":"04-12-
2007","url":"http://moonstone.caret.local:8080/portal/site/mercury","
siteType":null,"id":"mercury"}]}

You can find more documentation about this on our Sakai Confluence page :

http://bugs.sakaiproject.org/confluence/display/MYSAK/Home