[DAS] Dalliance: a new genome DAS client

[Thomas Down]

As some of you already know, I've been experimenting recently with a
web-based DAS client for genomic data.  It's still in
a unashamedly prototypical state (in particular, some of the popups and
configuration stuff is outright clunky, and we know it!), but we're starting
to find it quite useful, and would be interested to receive more feedback.
 So if you're curious, you can try it here:

               http://www.biodalliance.org/human/ncbi36/

It's a fully-fledged DAS/1.53 client (with a few bits of DAS/1.6, and
hopefully rather more coming soon), but has one major caveat: since it's
pure Javascript code running in your web browser, there are limitations to
which servers it can connect to.  Specifically, it will only work with DAS
servers that implement the W3C cross-origin resource sharing model (which
has been discussed on this list before, but drop me a line if you've got any
questions).  What does this mean in practice?  If you're adding datasources
from the registry, things are simple because Dalliance will only allow you
to add CORS-enabled sources (a huge thanks to Jonathan Warren for adding
some support for this in the registry).  If you run your own DAS servers and
don't list them in the registry, you'll need to check for CORS compatibility
yourself.  The latest versions of Proserver and Dazzle should both be okay.

All comments, suggestions, and bug reports are welcome!

                   Thomas Down.