Hi there
'
jensen bredal wrote:
Hello,
I need to build a new web system. It is required that i use SOA .
Can someone tell me briefly what that means in practise. I have read
some rather abstract documents, describing the idea but i yet need to find
a practical guide to kick of my project.
I can understand your need for a definition and some "get me started"
document. I was in need for this, too, but there's so much hype around
"services" these day, that they seem to forget the A in SOA.
In my opinion this is a matter of architecture. For instance - I have
been building services (the SOA way) for years - without using WebServices.
Bottom line:
You can have a SOA without WebServices, but it kinda difficult not have
a SOA with WebServices. Difficult because WebServices is build around
the idea of SOA.
So, you next question is: OK, I do WebServices equals I do SOA, right?
Well, ahem. You could do a lot of "bad practices", that makes you "SOA"
so not Service-Oriented that it is useless and you do not gain the
benefits, that's usually involved when runnig a SOA.
The short answer to your question is, although the info you gave was
very limited:
1)
Start out with WebServices.
2)
Build coarse-grained WebServices
3)
Pass-in and return as much as possible in one network round trip, ie.
one call to the WebService.
4)
Behind the scenes (your WebSevice interface) use common OO design and
programming.
5)
Use XML schemas to describe the structures (custom objects) you are
passing to/from the webservices, maybe including your messages
(operations). That is, use the Contract-First approach. See
www.thinktecture.com. Christian has a faaaantastic article on the topic.
Then, import these structures (.xsd files) into the .wsdl for the
webservice and generate the code you need using wsdl.exe.
That is common guidelines. I can not to into more specific parts as I do
not know what your application requirements are..? As always...It
depends... :-)
Regards
Henrik
websolver.blogspot.com
