Book Image

SOA Made Simple

Book Image

SOA Made Simple

Overview of this book

SOA is an industry term which is often preached like a religion rather than taught like a technology, and over time, grasping the concept has become unnecessarily difficult. Many companies proclaim that they don't know where to begin with SOA, while others have begun their SOA effort but haven't reaped the benefits they were convinced it would bring. "SOA Made Simple"ù unveils the true meaning of Service Oriented Architecture and how to make it successful so that you can confidently explain SOA to anyone! "SOA Made Simple"ù explains exactly what SOA is in simple terminology and by using real-life examples. Once a simple definition is clear in your mind, you'll be guided through what SOA solves, when and why you should use it, and how to set up, design and categorize your SOA landscape. With this book in hand you'll learn to keep your SOA strategy successful as you expand on it. "SOA Made Simple"ù demystifies SOA, simply. It is not difficult to grasp, but for various reasons SOA is often made unnecessarily complex. Service-orientation is already a very natural way of thinking for business stakeholders that want to realize and sell services to potential clients, and this book helps you to realize that concept both in theory and practice. You'll begin with a clear and simple explanation of what SOA is and why we need it. You'll then be presented with plain facts about the key ingredients of a service, and along the way learn about service design, layering and categorizing, some major SOA platform offerings as well as governance and successful implementation. After reading "SOA Made Simple"ù you will have a clear understanding of what SOA is so you can implement and govern SOA in your own organization.
Table of Contents (17 chapters)
SOA Made Simple
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Events


The previous chapter introduced events as a mechanism to signal that something noteworthy happened. Events are important in an SOA platform, thus:

  • From a business point of view, events are a natural way to represent information. Businesses and their surrounding ecosystem of suppliers, partners, and clients cause and react with events continuously: a customer moving to a different address, a new purchase order, receiving an invoice from a supplier, sending a bill to a partner, and so on.

  • From a technical point of view, events improve the decoupling between software components. Software components are not required to know of each other’s existence any more.

An event contains a payload that provides information on the occurrence. The following code snippet shows the event payload that describes a new order that has just been received. This event is published by the Customer Web Portal and received by the service OrderService for further processing.

<?xml version=”1.0”?>
<order...