REST vs. SOAP In Amazon Web Services

tadghin writes "I was recently talking with Jeff Barr, creator of syndic8 and now Amazon's chief web services evangelist. He let drop an interesting tidbit. Amazon has both SOAP and REST interfaces to their web services, and 85% of their usage is of the REST interface." Read on for some more thoughts and information on REST and Web services, including information about a free Web services seminar on April 22nd. " Despite all of the corporate hype over the SOAP stack, this is pretty compelling evidence that developers like the simpler REST approach. (I'm sure there are applications where SOAP is better, but I've always liked technologies that have low barriers to entry and grassroots adoption, and simple XML over HTTP approach seems to have that winning combination.)

Amazon's web services have attracted a thriving community, people are making real money building alternate interfaces to Amazon and collecting Associates commissions on the resulting sales, and there are even tool developers who have come up with the creative business model of agreeing with their users to have some percentage of the transactions use the tool developer's Associates id rather than the site owner's. Cool.

Amazon is holding a free all day web services workshop on April 22 at the O'Reilly Emerging Technologies Conference. The event is open to people not registered at the conference (though space is limited to 50 people).

P.S. Slashdot really ought to have web services as a topic area! Despite being over-hyped, this is a really important area, and there's a lot cooking. Amazon's web services"

Comments

Where do xCBL and cXML fit in?

[sonamchauhan]

Can someone enlighten me how the usage (described below) of two Ecommerce dialects -- CommerceOne's xCBL and Ariba's cXML -- is classified?

I don't think the usage below can be classified as either Web Service, XML-RPC, SOAP, or REST. However, this usage comprises the majority of XML-based Ecommerce transactions I see in mainstream business these days (I work for a large office supplies company).

"The Usage"
-----------------
A business procedure (say, "place a purchase order") is executed by a simple transfer of an XML document. This XML document conforms to the standard it follows -- i.e. it is valid XML according to the standard's DTD/schema for that particular transaction.

For example, to send an XML purchase order via HTTP POST, the buyer would do the following sort of POST (HTTP protocol approximated below):

HTTP POST....
Content-Type: text/xml

<PurchaseOrder>
<Blah....

Note: the content type is "text-xml". There are no CGI params -- the XML document itself comprises the body of the HTTP POST. The seller sends back a synchronous response document (same TCP connection as the POST, but reverse direction). This 'sync response' must carry an HTTP 200 response header, but can also carry an XML document (this depends on the standard).

HTTP 200/OK
Content-Type: text/xml

<ConfirmationOfPurchaseOrder>
<Blah....

The submitter party processes this response.

Note, there are no standardised 'sections' of XML in the document (like there are with SOAP or Web-Services (unsure?) ). Also, unlike REST, there is no usage of other HTTP methods - DELETE, GET, etc -- only POST. The XML document itself specifies the procedure being carried out (a richer, and hence better, approach).

For example, to do an order cancellantion, another XML document is POST-ed.

HTTP POST....
Content-Type: text/xml

<PurchaseOrderCancellation>
<OrderReference attrib="blah">
<Blah....

So, does this sort of usage have a name (besides the name of the business standard)? What advantages do other approaches like Web Services bring to the table?