2008/5/22 Dan Brickley <[EMAIL PROTECTED]>: > Peter Saint-Andre wrote: >> >> On 05/12/2008 12:53 PM, Dan Brickley wrote: >>> >>> I've been hacking around with >>> the use of XMPP as a data bus for RDF querying using SPARQL (as Peter >>> well knows, being my XMPP helpline). Some notes on that at [1]. >> >>> [1] http://danbri.org/words/2008/02/11/278 >> >> See also http://crschmidt.net/semweb/sparqlxmpp/ > > Yup, Chris wrote this up based on IRC chats after the original design > discussions I had with you. He beat me to running code :) The mapping of > SPARQL result set format to XMPP IQ markup mutated a bit over time, so there > isn't clean interop currently between his python and my jqbus java stuff. > But it's all wrong anyway since large resultsets are too big for one IQ; > need to move to some batching or attachments-based model. >
I have never looked into XMPP, except for observing that some Instant Mesaging applications use it, so sorry if these sound like mundane introductory questions. Does XMPP have a reliable error handling mechanism outside of the HTTP model? HTTP doesn't exactly have the best error handling so another format would be nice. Would SPARQL-RESULT-XML be only inserted using namespaces into XMPP XML documents or does XMPP define a MIME-like splitting with attachment handling? You said something above about resultsets being too big so I assume there is a maximum envelope size for XMPP, correct? Would it be a good place to think about distributed SPARQL querying as a mainstream operation, since Peer to peer mechanisms go against the grain of database driven SPARQL already. How does authorisation and encryption work for XMPP, as I currently utilise HTTPS transport with HTTP type authentication for determining whether to execute sparql queries based on the requestor privileges and return encrypted results to avoid network sniffing. Has oauth actually been implemented as a proof of concept for use with XMPP, as from my quick glance it deals with HTTP a lot in the examples. Have any links between OpenID and XMPP been investigated which could be utilised for enabling distributed authenticated SPARQL querying, or does this come for free with the oauth strategy? Hope that isn't too many questions at once! XMPP sounds like a good place to look into for supporting these features which are either unreliable or hard to implement on top of HTTP based sparql endpoints. Cheers, Peter
