Learning NServiceBus Sagas

214 Pages·2014·13.578 MB·English

by  Rich Helton

Learning NServiceBus Sagas
Discover how to design, build, and test sagas and
messaging with NServiceBus
Rich Helton
professional expertise distilled
P U B L I S H I N G
BIRMINGHAM - MUMBAI
Learning NServiceBus Sagas
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First published: January 2015
Production reference: 1240115
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ISBN 978-1-78217-349-6
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Credits
Author Project Coordinator
Rich Helton Mary Alex
Reviewers Proofreaders
Neil Bourgeois Samuel Redman Birch
Prashant Brall Maria Gould
Mark Huber Bernadette Watkins
Commissioning Editor Indexer
Usha Iyer Monica Ajmera Mehta
Acquisition Editor Graphics
Kevin Colaco Valentina D'silva
Content Development Editors Production Coordinator
Akshay Nair Nilesh R. Mohite
Priya Singh
Cover Work
Arvindkumar Gupta
Technical Editor
Edwin Moses Nilesh R. Mohite
Copy Editors
Sarang Chari
Puja Lalwani
Veena Mukundan
About the Author
Rich Helton, as a principal software engineer, builds and reviews large-scale
systems and trains hundreds of developers as well.
Rich has spent over 2 decades in designing and building systems. During this
time, he has built, architected, and designed multiple systems, as well as managed
many different technical teams. He has built many large-scale enterprise solutions
using the most popular C# and Java frameworks and has expertise in the financial,
aeronautical, and security domains.
Rich's passion for designing and teaching HTML5, ESBs, ORM's test-driven
development, NoSQL, iOS, IoCs, and cloud and iPad development was discovered
while training developers and architects. He freely shares some of the slides from
these trainings on http://www.slideshare.net/rhelton_1.
I would like to thank my wife, Johennie, and my daughters, Ashley
and Courtney, for their ongoing support.
About the Reviewers
Neil Bourgeois is a software engineer at Pentair Technical Solutions, where he
leads the Engineering Software team. Solutions he has architected and implemented
include a high-volume metering and billing system for the utilities industry and
an industry-leading 3D engineering tool for the industrial heat-tracing field. He
applies the discipline of Agile software development to his work and believes
that great software comes from great team cultures. He strives to lead his teams
to great cultures.
Prashant Brall is a principal consultant and senior software architect/developer who
uses Microsoft technologies. He works for Veritec Pty Ltd (www.veritec.com.au) in
Canberra, Australia, and has been developing software for the past 18 years. He enjoys
writing about his experiences on his blog at https://prashantbrall.wordpress.com.
Prashant has also reviewed the book Instant AutoMapper, Packt Publishing.
In his leisure time, he enjoys watching movies with his wife and playing
musical instruments.
I would like to thank my fantastic wife, Jhumur, for being my best
friend and for all the love and support she has given me. I would
also like to thank my parents Mr. Hem Brall and Mrs. Prabha Brall
for all the guidance, love, and care they have given me.
Mark Huber is a developer, team manager, and general-purpose tech enthusiast
who lives and works in Dallas, Texas. In the last several years, he has focused on
specializing in large-scale web platforms in the automotive market. He has spent
the majority of his time in the .NET environment, but believes the key to mastering
your preferred domain is expanding beyond traditional boundaries to look at
how other languages and technologies approach the same problems. He has been
an avid researcher of other platforms including Java, Ruby, Python, and others.
He is also a strong advocate of interweaving .NET projects with supporting open
source technologies not traditionally considered with a .NET platform, such as
ElasticSearch, Redis, RabbitMQ, Memcached, and others.
Mark is currently a software development manager working at Dealer.com, a
Dealertrack technology solution. He is privileged to work with a team of developers,
QA, DevOps, product owners, and many others, who truly live the principles and
values of the Agile Manifesto (http://agilemanifesto.org/) as well as view their
work through the lens of the Software Craftsmanship Manifesto (http://manifesto.
softwarecraftsmanship.org/).
I would like to extend a heartfelt thank you to my colleagues,
mentors, friends, and most importantly my family, who have been
an unending stream of support and growth over the years. Without
them, I would not be where I am today.
"Perfecting oneself is as much unlearning as it is learning."
- Edsgar Dijkstra
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Table of Contents
Preface 1
Chapter 1: Introduction to Sagas 9
A brief introduction to ESBs 10
Event-driven jobs 14
Additional SOA patterns 15
The publish-subscribe pattern 15
The request-reply pattern 17
The gateway pattern 18
The source code 19
The DataBus pattern 21
Timeout patterns 22
Message mutation patterns 28
The source code 29
Message encryption patterns 30
The source code 30
The ScaleOut pattern 32
The saga design pattern 32
Sagas – what are they good for? 34
Summary 37
Chapter 2: NServiceBus Saga Architecture 39
Upgrading from NSB version 4 to 5 39
The saga workflow 41
Message flow 48
Deployment 55
ServiceInsight 56
Summary 58