[Mulgara-general] firefox bug and server config

[Paul Gearon]

On Fri, Sep 4, 2009 at 10:20 AM, Gregg Reynolds <dev at mobileink.com> wrote:
> Hi,
>
> I'm working on a simple web page and javascript for exploring Mulgara.  I
> seem to have run into a firefox bug, whereby a GET transaction is completed
> (readyState == 4) but the status == 0.  I'm sending the get request to a
> vanilla mulgara instance on localhost:8080 that I know works.  In
> LiveHTTPHeaders I can see the request and response, both of which look
> fine.  But the XMLHttpRequest object seems to be discarding the data.  This
> is on OS X 10.5.8, FF 3.5.2.

This is an area I haven't really explored so I'll need to get up to speed.

> I've been beating my head on this for about eight hours now and I'm
> completely flummoxed (how I hate software!).  My suspicion however is that
> this might be connected to the new support
> (https://developer.mozilla.org/En/HTTP_access_control) for the CORS
> standard.  I.e., if the mulgara response were to include the
> "Access-Control-Allow-Origin" header, it might possibly maybe work.  (See it
> in action, with LiveHTTPHeaders on, at
> http://arunranga.com/examples/access-control/simpleXSInvocation.html  Dunno
> what else to try at this point.

Do you know exactly what is going on between FF and Mulgara? This
might provide some further hints.  If you're not using it already,
then go through HTTP Tracer:
  http://simile.mit.edu/wiki/HTTPTracer

> The problem is I have no idea how to configure Jetty and I'm hoping somebody
> on the list does and is willing to save me the trouble of learning.  ;)

I know a little, but I'm not an expert in any sense of the word.

The other thing to be aware of is the URLs that you're using. I had
been successfully using http://localhost:8080/sparql?query=.... using
wget, but it failed inexplicably on cURL. It turned out that the Jetty
has to register the webapp with a trailing / character, and using it
without would result in a redirect. So the safe URL to use was
http://localhost:8080/sparql/?query=....

The combination of /? looks strange to me, but I guess it makes sense.

> FWIW, the little doo-dad I'm building (which could compete with the iTQL
> CLI, if I could just get Firefox to cooperate!) is at
> http://bitbucket.org/gar/mulligan/overview/ in case anybody's interested.

How does it compare to the WebUI? (you HAVE used the WebUI, right?)

> Very simple, just some fancy jQuery stuff that exposes the HTTP request
> structure and sparql/tql query string.  It worked yesterday, on a windows
> machine.  Honest!  But to debug the xmlhttprequest problem I'm just using a
> mimimal webpage.

Regards,
Paul Gearon