Semergence

wadl is the Web Application Description Language, which is an XML specification to describe RESTful web services. Seeing as the current version of the spec is a mere 31 pages, I am excited to see this move forward. Many people would consider the lack of a description specification from REST web services a set back, so having a simple spec like WADL can be used to help the converts. I can see a future version of Rails generating WADL documents natively.

Patrick Mueller explores why twitter is slow. The answer? It turns out that Web Architecture actually matters. If you are writing a Web Application (yes, that’s capital W and A), then you need to understand Web Architecture.

Hat’s off to Tim Bray at today’s Keynote at RailsConf to trumpeting Web Architecture and specifically the Atom Publishing Protocol as a great example of correct Web Architecture.

Tim Berners-Lee is giving the keynote to WWW2007 titled The Two Magics of Web Science, which talks about linking data.

Ironically, that document doesn’t link to any RDF documents.

Tim Bray writes a nice explanation of REST. I love collecting this stuff in order to convert ^H^H^H teach my friends all about the “yummy goodness” that is REST. And hey, any name that reminds me of naps has got to be good.

Softies on Rails is posting an excellent REST tutorial series. They are doing a great job in describing how a web application is just a collection of resources (and not necessarily web pages), and how you can think of your web application as the gateway to manipulate those resources. If you want to learn REST, and good web architecture, this tutorial series is the way to start.

This reminds me of the great “A resource is a web page about your car, not your car itself” debate.

Norm Walsh sums this debate up nicely:

Suffice it to say that some folks think http://example.org/some/path must identify “a document” (what the AWWW calls an “information resource”) and some folks think it can identify anything at all.

In any case, thinking of your web application as a collection of resources is the way to go. You don’t usually need to get all carried away with “what is a resource?” unless you are trying to model knowledge, but that’s another story…

Querying the web might get a bit easier, with the union of SPARQL directly with HTTP. TripleSoup, a promising proposal at Apache, aims to expose Triple Stores (RDF databases) directly via HTTP.

This reminds me of URIQA, which is an effort to provide native HTTP methods for accessing metadata about a certain resource. URIQA was interesting because it allows you to say

MGET /foo HTTP/1.1

which means “Retrieve the metadata for resource `/foo`”

It looks like TripleSoup is a bit different, in that the URI in the request methods is some type of application. TripleSoup seems to be a gateway directly into the triple store, whereas URIQA masks the concept of talking to the triple store. In URIQA, it looks like the triple store *is* the server you are connecting to. With TripleSoup, the triple store is located at the URI you are sending requests to.

URIQA’s advantage is that you don’t need to know the URI to the application or triple store, you can just send an MGET to the resource. Of course, URIQA doesn’t handle queries with SPARQL.

My first question with TripleSoup is, how would I discover the URI that I can use for querying? It’s the same problem that URIQA tries to solve, “I know the URI for the resource, but I want to get its metadata.” I can ask that question in SPARQL, but who do I ask?

Best of luck to the TripleSoup team, really looking forward to the code.

Whenever Tim Berners-Lee speaks, I listen. He spoke to the US House of Representatives on The Future of the World Wide Web on March 1st, 2007.

There were references to RDF and OWL and how Data Is The New Document. Ironically, I couldn’t find an RDF document that described the event or the transcript.

Sit back, enjoy, and get pumped up for building web applications again.

I created a new Rails project today, using Rails 1.1 for the first time. There’s a little gem inside Controllers created by the scaffolding:

# GETs should be safe (see http://www.w3.org/2001/tag/doc/whenToUseGet.html)
verify :method => :post, :only => [ :destroy, :create, :update ],
:redirect_to => { :action => :list }

Not only is that so terse and simple to express in Ruby on Rails, but it’s the right thing to do. Any action that may result in modification of the resource should be performed with POST.

It’s great to see these types of Web Architecture best practices enforced, so that more applications are built with web friendliness.

famfamfam has kindly provided a set of Free Icons of all different shapes and sizes. They look great.

> Need icons for your new website or web application, at the best price there is (free!)?