Mastering Python Design Pattern

212 Pages·2015·2.05 MB·english

by  Sakis Kasampalis

Mastering Python Design
Patterns
Create various design patterns to master the art of
solving problems using Python
Sakis Kasampalis
BIRMINGHAM - MUMBAI
Mastering Python Design Patterns
Copyright © 2015 Packt Publishing
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First published: January 2015
Production reference: 1220115
Published by Packt Publishing Ltd.
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ISBN 978-1-78398-932-4
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Credits
Author Project Coordinator
Sakis Kasampalis Aboli Ambardekar
Reviewers Proofreaders
Evan Dempsey Ameesha Green
Amitabh Sharma Joyce Littlejohn
Yogendra Sharma
Indexer
Patrycja Szabłowska
Tejal Soni
Commissioning Editor
Graphics
Kunal Parikh
Abhinash Sahu
Acquisition Editor
Production Coordinator
Owen Roberts
Aparna Bhagat
Content Development Editor
Cover Work
Sumeet Sawant
Aparna Bhagat
Technical Editors
Tanvi Bhatt
Gaurav Suri
Copy Editors
Shivangi Chaturvedi
Nithya P.
Adithi Shetty
About the Author
Sakis Kasampalis (@SKasampalis) is a software engineer living in the
Netherlands. He is not dogmatic about particular programming languages and tools;
his principle is that the right tool should be used for the right job. One of his favorite
tools is Python because he finds it very productive.
Sakis was also the technical reviewer of Mastering Object-oriented Python and Learning
Python Design Patterns, published by Packt Publishing.
I want to thank my sweetheart, Georgia, for supporting this effort.
Many thanks to Owen Roberts who encouraged me to write this
book. I also want to thank Sumeet Sawant for being a very kind and
cooperative content development editor. Last but not least, I want to
thank the reviewers of this book for their valuable feedback.
About the Reviewers
Evan Dempsey is a software developer from Waterford, Ireland. When he isn't
hacking in Python for fun and profit, he enjoys craft beers, common Lisp, and
keeping up with modern research in machine learning. He is a contributor to several
open source projects.
Amitabh Sharma is a professional software engineer. He has worked extensively
on enterprise applications in telecommunications and business analytics. His work
is focused on service-oriented architecture, data warehouses, and languages such as
Java, Python, and others.
I would like to thank my grandfather and my father for allowing me
to learn all that I can. I would also like to thank my wife, Komal, for
her support and encouragement.
Yogendra Sharma was born and brought up in a small but cultural town,
Pratapgarh, in the state of Rajasthan. His basic education has been imparted in his
hometown itself, and he completed his BTech in Computer Science from Jaipur.
He is basically an engineer by heart and a technical enthusiast by nature.
He has vast experience in the fields of Python, Django framework, web app security,
networking, Web 2.0, and C++.
Along with CCNA, many other esteemed certifications have been awarded to him.
He is an active member of International Association of Engineers, Ubuntu, India,
and Computer Society of India.
More recently, he participated in bug bounty programs and won many bug bounties,
including the respected Yahoo, Ebay, PayPal bug bounty. He has been appointed
as security researcher for several respected organizations, such as Adobe, Ebay,
Avira, Moodle, Cisco, Atlassian, Basecamp, CodeClimate, Abacus, Rediff, Assembla,
RecruiterBox, Tumbler, Wrike, Indeed, HybridSaaS, Sengrid, and SnapEngag.
He has reviewed many books from reputed publishing houses. You can find him on
LinkedIn at http://in.linkedin.com/in/yogendra0sharma.
I would like to thank all my friends who always encouraged me to
do something new and believing in me.
Patrycja Szabłowska is a Python developer with some Java background,
with experience mainly in backend development. She graduated from Nicolaus
Copernicus University in Toruń, Poland.
She is currently working in Warsaw, Poland, at Grupa Wirtualna Polska. She is
constantly exploring technical novelties and is open-minded and eager to learn about
the next Python library or framework. Her favorite programming motto is Code is
read much more often than it is written.
I'd like to thank my husband, Wacław, for encouraging me to explore new frontiers,
and also my parents for teaching me what matters the most.
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Table of Contents
Preface 1
Chapter 1: The Factory Pattern 9
Factory Method 9
A real-life example 10
A software example 10
Use cases 10
Implementation 12
Abstract Factory 20
A real-life example 20
A software example 21
Use cases 21
Implementation 21
Summary 27
Chapter 2: The Builder Pattern 29
A real-life example 30
A software example 30
Use cases 31
Implementation 34
Summary 43
Chapter 3: The Prototype Pattern 45
A real-life example 47
A software example 48
Use cases 48
Implementation 49
Summary 54