ServiceTechMag.com > Archive > Issue XXIV: December 2008

Issue XXIV December 2008

The Case for Single-Purpose Services: Understanding
the Non-Agnostic Context and a Strategy for Implementation

Herbjorn Wilhelmsen

Herbjorn Wilhelmsen

Justifying the extra investment for developing a single-purpose service – a service expected to solve only one large business problem - instead of putting the single-purpose logic inside a non-service-oriented application can be challenging. Reuse, the most popular motivation for creating services, will not apply. So where's the business case? Acceptable justifications can include: enabling support for multiple providers, isolating logic from change, centralizing IT-support for a given business process, service composition optimization, and separation of concerns. Although performance is commonly referenced as a reason to not create services, that line of thought is not always valid. With the help of patterns referenced from the recently published SOA Design Patterns book [REF-1] and the soapatterns.org site [REF-17], this article will delve into these issues as we explore the case for the single-purpose service. Services are useful, but they come with a price tag. The cost of developing a service is higher than the cost of developing a traditional (non-service-oriented) application, primarily due to the extra work and infrastructure required. Another common concern when creating and consuming services is the possibility of a performance hit. Together these issues hint that even if you've decided to wholeheartedly adopt SOA, you may not want or need to...


Message Auditing in Service-Oriented Architecture

Kanu Tripathi

Kanu Tripathi

"This article explores the subject of message auditing in a typical service-oriented system implementation. A case is built for having a system for auditing messages, followed by an exploration of the requirements this type of system can address. A candidate architecture and design of the system is the provided, concluding how the original goals can be attained. Finally some examples are given and some caveats are highlighted. Any serious service-oriented system implementation can be comprised of a number of services assembled into compositions. When you have a maze of services being called from many different clients, it can easily result in a formidable amount of information being passed around in form of messages. If principles of service-oriented design are followed, these messages would be in a standardized format. leading to a variety of possibilities as to how mechanisms can be positioned to filter and persist the messages and to also extract business intelligence from them in an arbitrary manner. The impact of standards-based messaging on auditing is as deep and as sweeping as its impact on the field of integration in general. Not much attention has been given to auditing messages in service-oriented eco-systems. Most modern infrastructure and service bus platforms provide simple message auditing mechanisms, for example, by writing messages to...


REST-Inspired SOA Design Patterns

Raj Balasubramanian

Raj Balasubramanian

Every major development platform now promotes support for the creation of solutions based on SOA. Historically, the most common means of building services for SOA has been via the Web services (WS-*) platform. There has recently been an emerging paradigm of using the simpler services development paradigm by employing the fundamental principles that makes the Web successful, termed REST (Representational State Transfer). This term was coined by Roy Fielding, as part of his PhD dissertation, which outlined some basic principles for constructing distributed applications. There are some key characteristics that differentiate the design of services using a RESTful style and this body of work is a first step toward formalizing these characteristics as design patterns. With the help of Jim Webber, David Booth, Thomas Erl, and others, first drafts of the following five REST-inspired patterns have been contributed as candidate patterns at SOAPatterns.org: • Alternative Format • Entity Linking • Layered Redirect • Transport Caching • Uniform Contract. I'd like to encourage you review these patterns and provide feedback using the online form at SOAPatterns.org. The plan is to make the patterns available for public review for at least 6-12 months before they are considered ready for inclusion in the master SOA patterns catalog...


SOAPatterns.org - A Community Site Dedicated to SOA Patterns

 

SOA Pattern

A new Web site has been launched dedicated to the on-going development of SOA patterns and the expansion of the master SOA pattern catalog. SOAPatterns.org publishes summarized descriptions of all 85 patterns from the recently released book "SOA Design Patterns" along with 20 candidate patterns that are currently under review and in development. You can join the SOA patterns community by providing feedback and reviews and contributing your own patterns...



2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006