[Mulgara-general] New WebUI

[Paul Gearon]

Hi everyone,

This WebUI in Mulgara has recently undergone a complete re-write,
making it much lighter weight. However, we have endeavoured to keep
all the old functionality unchanged. There are also some substantial
new features that should be of interest to most users.

The WebUI is accessed by pointing a browser to a host running a
standalone Mulgara instance. By default, Mulgara runs its web services
on port 8080, so you'll usually use a URL of:
http://localhost:8080/webui
Cosmetically, you'll see that we now use a style similar to the
mulgara.org website. But the real changes are under the hood.

The first major change is that the Query box now autodetects SPARQL.
This lets you type any SPARQL query, and it will execute as normal. We
are still working on 100% SPARQL compliance, but this has been
steadily improving all year. TQL commands and queries still work
exactly the same, so if you never use SPARQL you will not see the
difference.

Next, graph URIs need no longer look like: rmi://host/server#name
Instead, *any* valid absolute URI can be used (relative URIs are
coming). This means you can create and use graphs with names like:
  http://yourdomain.com/mydata
  urn:www.agxml.org:schemas:all:2:0
  foo:bar

If you create a graph with a given URI then you can insert and select
from it as usual. Mulgara also offers the option of querying graphs
that you haven't defined. If the URI of the graph is a URL that
Mulgara understands, then it will attempt to retrieve data from that
source and interpret it accordingly (through the mechanism we call
"Resolvers"). For instance, you can find out the all the classes in
RDF by querying the ontology published at the location described in
the RDF namespace URL:
  select $class from <http://www.w3.org/1999/02/22-rdf-syntax-ns>
where $class <rdf:type> <rdfs:Class>;

Finally, the Graph URI field is now used as the default graph for
SPARQL queries. This field is initially set for the "Example Queries",
and has always been used as a location for resources returned from a
query, allowing URIs in results to be linked to queries about those
resources. While this has not changed, SPARQL queries which do not
define a FROM clause will also use this field as the location for the
data being queried. When combined with the URL resolution above, this
makes it easy to do things like testing the DAWG test cases, such as
the one at:
  http://www.w3.org/2001/sw/DataAccess/tests/r2#dawg-triple-pattern-003
Set the Graph URI to:
http://www.w3.org/2001/sw/DataAccess/tests/data-r2/triple-match/data-02.ttl
Type the test query into the Query Text field:
  SELECT *
  WHERE { ?a ?a ?b . }

The results are then rendered in the WebUI table layout.

We hope you like these new features. Many of them are quite new, so we
look forward to bug reports and feature requests.

Regards,
Paul Gearon