Gopalan Suresh Raj
Web Cornucopia
Gopalan's Profile
Archives
« November 2009
SunMonTueWedThuFriSat
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
     
       
Today
Click me to subscribe Download Open ESB
Syndication
Search

Table of Contents
Tags
bpel choreography ejb esb http integration javacaps javaee javaone jax-ws jbi management openesb orchestration process-oriented rest sca service-oriented soa soap wsdl xml xsd
Links
 


 
Referrers

Today's Page Hits: 274

Map of Visitors
Locations of visitors to this page
Caveat Emptor
This is my personal weblog. The contents of this Weblog represent my personal opinion which may differ from the official views of my employer, Sun Microsystems, Inc. or any past employers. I do not speak for my employer or any past employers.
View Gopalan Suresh Raj's profile on LinkedIn
« JBI/SOA Tips: For... | Main | JBI/SOA Tips: Protoc... »
Friday May 18, 2007
May
18
JBI/SOA Tips: Evolving Global Collaborations - Version Number Message Wrappers

In wire-centric integration for global collaborations, your Information model evolves over time. XML Schema and WSDL help you document those changes over time, and at any point in time, they help you validate your information model at that period in time. 

Explicitly add a version number attribute to the first element of both the request and the response message wrapper.

Version Number Message Wrappers
This will ensure the Message Exchange Pattern (MEP) and the schema of the exchanged messages evolve in tandem.

Over the years so much has been said about evolution and there are tomes of literature on the subject if you look around. Every organization has come up with their own solution to evolve their schemas and WSDLs based on a combination of facilities for evolution provided in the XML Schema specification, and their internal policies. Without over-simplifying the complexities involved in providing for versioning your information model, it is safe to say that adding a version number attribute to the first element of both the request and response message wrappers will allow you to have complete control over how to evolve your Message Exchange Patterns over time.

Assuming you have this simple mechanism in place, you have multiple approaches over how to evolve your collaborations over time. For one, as soon as the service receives the message, the whole message is not parsed, but an XPath query is executed on the message that looks for the value of the version number attribute of the first element of the message. Based on the version number, the message can now be routed to the appropriate version of the collaboration that can handle the message. I will, however, leave this topic for a more in-depth article on Evolving Service Collaborations for Wire-Centric Integration in the near future.


Like this write-up? Subscribe to receive more like it.


Posted at 12:10AM May 18, 2007 by Suresh Gopalan in A Tip a Day  |  Listen to this article Listen to this entry  |  Comments added Comments[2]
Tags:
Share This Post: del.icio.us | furl | simpy | slashdot | technorati | digg

Comments:

Can you make any diagrams smaller? They tend to be too big for Planet NetBeans. Also most of the information is not very relevant to NetBeans.

Posted by 87.114.128.40 on May 18, 2007 at 09:21 AM PDT #

They are most relevant to the NetBeans SOA Pack. Cheers Gopalan.

Posted by Gopalan Suresh Raj on May 18, 2007 at 09:43 AM PDT #

Post a Comment:
  • HTML Syntax: NOT allowed

Disclaimer: The contents of this Weblog represent my personal opinion which may differ from the official views of my employer, Sun Microsystems, Inc. or any past employers.

View blog top tags

Enter your email address:

Delivered by FeedBurner

[Valid RSS]