Search icon Close icon
Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Checkout

Change country

Modal Close icon
Country selected Country selected
country flag United States
Country selected
country flag Great Britain
Country selected
country flag India
Country selected
country flag Germany
Country selected
country flag France
Country selected
country flag Canada
Country selected
country flag Russia
Country selected
country flag Spain
Country selected
country flag Brazil
Country selected
country flag Australia
Country selected
country flag Singapore
Country selected
country flag Hungary
Country selected
country flag Ukraine
Country selected
country flag Luxembourg
Country selected
country flag Estonia
Country selected
country flag Lithuania
Country selected
country flag South Korea
Country selected
country flag Turkey
Country selected
country flag Switzerland
Country selected
country flag Colombia
Country selected
country flag Taiwan
Country selected
country flag Chile
Country selected
country flag Norway
Country selected
country flag Ecuador
Country selected
country flag Indonesia
Country selected
country flag New Zealand
Country selected
country flag Cyprus
Country selected
country flag Denmark
Country selected
country flag Finland
Country selected
country flag Poland
Country selected
country flag Malta
Country selected
country flag Czechia
Country selected
country flag Austria
Country selected
country flag Sweden
Country selected
country flag Italy
Country selected
country flag Egypt
Country selected
country flag Belgium
Country selected
country flag Portugal
Country selected
country flag Slovenia
Country selected
country flag Ireland
Country selected
country flag Romania
Country selected
country flag Greece
Country selected
country flag Argentina
Country selected
country flag Netherlands
Country selected
country flag Bulgaria
Country selected
country flag Latvia
Country selected
country flag South Africa
Country selected
country flag Malaysia
Country selected
country flag Japan
Country selected
country flag Slovakia
Country selected
country flag Philippines
Country selected
country flag Mexico
Country selected
country flag Thailand
Country selected
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Free Learning
Arrow right icon
Home > Programming > Design Patterns > Learning Python Design Patterns - Second Edition
Learning Python Design Patterns - Second Edition
Learning Python Design Patterns - Second Edition

Learning Python Design Patterns - Second Edition: , Second Edition

Arrow left icon
Profile Icon Zlobin Profile Icon Giridhar
Arrow right icon
$9.99 $35.99
Full star icon Full star icon Half star icon Empty star icon Empty star icon 2.8 (13 Ratings)
eBook Feb 2016 164 pages 2nd Edition
eBook
$9.99 $35.99
Paperback
$43.99
Subscription
Free Trial
Renews at $19.99p/m
Arrow left icon
Profile Icon Zlobin Profile Icon Giridhar
Arrow right icon
$9.99 $35.99
Full star icon Full star icon Half star icon Empty star icon Empty star icon 2.8 (13 Ratings)
eBook Feb 2016 164 pages 2nd Edition
eBook
$9.99 $35.99
Paperback
$43.99
Subscription
Free Trial
Renews at $19.99p/m
eBook
$9.99 $35.99
Paperback
$43.99
Subscription
Free Trial
Renews at $19.99p/m

What do you get with eBook?

Product feature icon Instant access to your Digital eBook purchase
Product feature icon Download this book in EPUB and PDF formats
Product feature icon Access this title in our online reader with advanced features
Product feature icon DRM FREE - Read whenever, wherever and however you want
OR

Contact Details

Modal Close icon
Payment Processing...
tick Completed

Billing Address

Table of content icon View table of contents Preview book icon Preview Book

Learning Python Design Patterns - Second Edition

Chapter 2. The Singleton Design Pattern

In the previous chapter, we explored design patterns and their classifications. As we are aware, design patterns can be classified under three main categories: structural, behavioral, and creational patterns.

In this chapter, we will go through the Singleton design pattern—one of the simplest and well-known Creational design patterns used in application development. This chapter will give you a brief introduction to the Singleton pattern, take you through a real-world example where this pattern can be used, and explain it in detail with the help of Python implementations. You will learn about the Monostate (or Borg) design pattern that is a variant of the Singleton design pattern.

In this chapter, we will cover the following topics in brief:

  • An understanding of the Singleton design pattern
  • A real-world example of the Singleton pattern
  • The Singleton pattern implementation in Python
  • The Monostate (Borg) pattern

At the end of the chapter, we...

Understanding the Singleton design pattern

Singleton provides you with a mechanism to have one, and only one, object of a given type and provides a global point of access. Hence, Singletons are typically used in cases such as logging or database operations, printer spoolers, and many others, where there is a need to have only one instance that is available across the application to avoid conflicting requests on the same resource. For example, we may want to use one database object to perform operations on the DB to maintain data consistency or one object of the logging class across multiple services to dump log messages in a particular log file sequentially.

In brief, the intentions of the Singleton design pattern are as follows:

  • Ensuring that one and only one object of the class gets created
  • Providing an access point for an object that is global to the program
  • Controlling concurrent access to resources that are shared

The following is the UML diagram for Singleton:

Understanding the Singleton design pattern

A simple way of implementing...

Lazy instantiation in the Singleton pattern

One of the use cases for the Singleton pattern is lazy instantiation. For example, in the case of module imports, we may accidently create an object even when it's not needed. Lazy instantiation makes sure that the object gets created when it's actually needed. Consider lazy instantiation as the way to work with reduced resources and create them only when needed.

In the following code example, when we say s=Singleton(), it calls the __init__ method but no new object gets created. However, actual object creation happens when we call Singleton.getInstance(). This is how lazy instantiation is achieved.

class Singleton:
    __instance = None
    def __init__(self):
        if not Singleton.__instance:
            print(" __init__ method called..")
        else:
            print("Instance already created:", self.getInstance())
    @classmethod
    def getInstance(cls):
        if not cls.__instance:
            cls.__instance...

Module-level Singletons

All modules are Singletons by default because of Python's importing behavior. Python works in the following way:

  1. Checks whether a Python module has been imported.
  2. If imported, returns the object for the module. If not imported, imports and instantiates it.
  3. So when a module gets imported, it is initialized. However, when the same module is imported again, it's not initialized again, which relates to the Singleton behavior of having only one object and returning the same object.

The Monostate Singleton pattern

We discussed the Gang of Four and their book in Chapter 1, Introduction to Design Patterns. GoF's Singleton design pattern says that there should be one and only one object of a class. However, as per Alex Martelli, typically what a programmer needs is to have instances sharing the same state. He suggests that developers should be bothered about the state and behavior rather than the identity. As the concept is based on all objects sharing the same state, it is also known as the Monostate pattern.

The Monostate pattern can be achieved in a very simple way in Python. In the following code, we assign the __dict__ variable (a special variable of Python) with the __shared_state class variable. Python uses __dict__ to store the state of every object of a class. In the following code, we intentionally assign __shared_state to all the created instances. So when we create two instances, 'b' and 'b1', we get two different objects unlike Singleton...

Singletons and metaclasses

Let's start with a brief introduction to metaclasses. A metaclass is a class of a class, which means that the class is an instance of its metaclass. With metaclasses, programmers get an opportunity to create classes of their own type from the predefined Python classes. For instance, if you have an object, MyClass, you can create a metaclass, MyKls, that redefines the behavior of MyClass to the way that you need. Let's understand them in detail.

In Python, everything is an object. If we say a=5, then type(a) returns <type 'int'>, which means a is of the int type. However, type(int) returns <type 'type'>, which suggests the presence of a metaclass as int is a class of the type type.

The definition of class is decided by its metaclass, so when we create a class with class A, Python creates it by A = type(name, bases, dict):

  • name: This is the name of the class
  • base: This is the base class
  • dict: This is the attribute variable

Now...

Understanding the Singleton design pattern

Singleton provides you with a mechanism to have one, and only one, object of a given type and provides a global point of access. Hence, Singletons are typically used in cases such as logging or database operations, printer spoolers, and many others, where there is a need to have only one instance that is available across the application to avoid conflicting requests on the same resource. For example, we may want to use one database object to perform operations on the DB to maintain data consistency or one object of the logging class across multiple services to dump log messages in a particular log file sequentially.

In brief, the intentions of the Singleton design pattern are as follows:

  • Ensuring that one and only one object of the class gets created

  • Providing an access point for an object that is global to the program

  • Controlling concurrent access to resources that are shared

The following is the UML diagram for Singleton:

A simple way of implementing...

Lazy instantiation in the Singleton pattern

One of the use cases for the Singleton pattern is lazy instantiation. For example, in the case of module imports, we may accidently create an object even when it's not needed. Lazy instantiation makes sure that the object gets created when it's actually needed. Consider lazy instantiation as the way to work with reduced resources and create them only when needed.

In the following code example, when we say s=Singleton(), it calls the __init__ method but no new object gets created. However, actual object creation happens when we call Singleton.getInstance(). This is how lazy instantiation is achieved.

class Singleton:
    __instance = None
    def __init__(self):
        if not Singleton.__instance:
            print(" __init__ method called..")
        else:
            print("Instance already created:", self.getInstance())
    @classmethod
    def getInstance(cls):
        if not cls.__instance:
            cls.__instance = Singleton()
        return...

Module-level Singletons

All modules are Singletons by default because of Python's importing behavior. Python works in the following way:

  1. Checks whether a Python module has been imported.

  2. If imported, returns the object for the module. If not imported, imports and instantiates it.

  3. So when a module gets imported, it is initialized. However, when the same module is imported again, it's not initialized again, which relates to the Singleton behavior of having only one object and returning the same object.

The Monostate Singleton pattern

We discussed the Gang of Four and their book in Chapter 1, Introduction to Design Patterns. GoF's Singleton design pattern says that there should be one and only one object of a class. However, as per Alex Martelli, typically what a programmer needs is to have instances sharing the same state. He suggests that developers should be bothered about the state and behavior rather than the identity. As the concept is based on all objects sharing the same state, it is also known as the Monostate pattern.

The Monostate pattern can be achieved in a very simple way in Python. In the following code, we assign the __dict__ variable (a special variable of Python) with the __shared_state class variable. Python uses __dict__ to store the state of every object of a class. In the following code, we intentionally assign __shared_state to all the created instances. So when we create two instances, 'b' and 'b1', we get two different objects unlike Singleton where we have just...

Left arrow icon

Page 1 of 10

Right arrow icon

Key benefits

  • Understand the structural, creational, and behavioral Python design patterns
  • Get to know the context and application of design patterns to solve real-world problems in software architecture, design, and application development
  • Get practical exposure through sample implementations in Python v3.5 for the design patterns featured

Description

With the increasing focus on optimized software architecture and design it is important that software architects think about optimizations in object creation, code structure, and interaction between objects at the architecture or design level. This makes sure that the cost of software maintenance is low and code can be easily reused or is adaptable to change. The key to this is reusability and low maintenance in design patterns. Building on the success of the previous edition, Learning Python Design Patterns, Second Edition will help you implement real-world scenarios with Python’s latest release, Python v3.5. We start by introducing design patterns from the Python perspective. As you progress through the book, you will learn about Singleton patterns, Factory patterns, and Façade patterns in detail. After this, we’ll look at how to control object access with proxy patterns. It also covers observer patterns, command patterns, and compound patterns. By the end of the book, you will have enhanced your professional abilities in software architecture, design, and development.

Who is this book for?

This book is for Software architects and Python application developers who are passionate about software design. It will be very useful to engineers with beginner level proficiency in Python and who love to work with Python 3.5

What you will learn

  • Enhance your skills to create better software architecture
  • Understand proven solutions to commonly occurring design issues
  • Explore the design principles that form the basis of software design, such as loose coupling, the Hollywood principle and the Open Close principle among others
  • Delve into the object-oriented programming concepts and find out how they are used in software applications
  • Develop an understanding of Creational Design Patterns and the different object creation methods that help you solve issues in software development
  • Use Structural Design Patterns and find out how objects and classes interact to build larger applications
  • Focus on the interaction between objects with the command and observer patterns
  • Improve the productivity and code base of your application using Python design patterns

Product Details

Country selected
Publication date, Length, Edition, Language, ISBN-13
Publication date : Feb 15, 2016
Length: 164 pages
Edition : 2nd
Language : English
ISBN-13 : 9781785887376
Category :
Programming
Languages :
Python
Concepts :
Design Patterns

What do you get with eBook?

Product feature icon Instant access to your Digital eBook purchase
Product feature icon Download this book in EPUB and PDF formats
Product feature icon Access this title in our online reader with advanced features
Product feature icon DRM FREE - Read whenever, wherever and however you want
OR

Contact Details

Modal Close icon
Payment Processing...
tick Completed

Billing Address

Product Details

Publication date : Feb 15, 2016
Length: 164 pages
Edition : 2nd
Language : English
ISBN-13 : 9781785887376
Category :
Programming
Languages :
Python
Concepts :
Design Patterns

Packt Subscriptions

See our plans and pricing
Modal Close icon
$19.99 billed monthly
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Simple pricing, no contract
START FREE TRIAL
BUY NOW
$199.99 billed annually
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Choose a DRM-free eBook or Video every month to keep
Feature tick icon PLUS own as many other DRM-free eBooks or Videos as you like for just $5 each
Feature tick icon Exclusive print discounts
START FREE TRIAL
BUY NOW
$279.99 billed in 18 months
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Choose a DRM-free eBook or Video every month to keep
Feature tick icon PLUS own as many other DRM-free eBooks or Videos as you like for just $5 each
Feature tick icon Exclusive print discounts
START FREE TRIAL
BUY NOW

Frequently bought together

Python Unlocked
Python Unlocked
Read more
Dec 2015 172 pages
Full star icon 3 (2)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $43.99
$9.99 $35.99
$43.99
Mastering Python
Mastering Python
Read more
Apr 2016 486 pages
Full star icon 4 (11)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $43.99
$9.99 $35.99
$43.99
Learning Python Design Patterns - Second Edition
Learning Python Design Patterns - Second Edition
Read more
Feb 2016 164 pages
Full star icon 2.8 (13)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $43.99
$9.99 $35.99
$43.99
Stars icon
Total $ 131.97
Python Unlocked
$43.99
Mastering Python
$43.99
Learning Python Design Patterns - Second Edition
$43.99
Total $ 131.97 Stars icon
Banner background image

Table of Contents

12 Chapters
1. Introduction to Design Patterns Chevron down icon Chevron up icon
1. Introduction to Design Patterns
Understanding object-oriented programming
Major aspects of object-oriented programming
Object-oriented design principles
The concept of design patterns
Patterns for dynamic languages
Classifying patterns
Summary
2. The Singleton Design Pattern Chevron down icon Chevron up icon
2. The Singleton Design Pattern
Understanding the Singleton design pattern
Lazy instantiation in the Singleton pattern
Module-level Singletons
The Monostate Singleton pattern
Singletons and metaclasses
A real-world scenario – the Singleton pattern, part 1
A real-world scenario – the Singleton pattern, part 2
Drawbacks of the Singleton pattern
Summary
3. The Factory Pattern – Building Factories to Create Objects Chevron down icon Chevron up icon
3. The Factory Pattern – Building Factories to Create Objects
Understanding the Factory pattern
The Simple Factory pattern
The Factory Method pattern
The Abstract Factory pattern
The Factory method versus Abstract Factory method
Summary
4. The Façade Pattern – Being Adaptive with Façade Chevron down icon Chevron up icon
4. The Façade Pattern – Being Adaptive with Façade
Understanding Structural design patterns
Understanding the Façade design pattern
A UML class diagram
Implementing the Façade pattern in the real world
The principle of least knowledge
Frequently asked questions
Summary
5. The Proxy Pattern – Controlling Object Access Chevron down icon Chevron up icon
5. The Proxy Pattern – Controlling Object Access
Understanding the Proxy design pattern
A UML class diagram for the Proxy pattern
Understanding different types of Proxies
The Proxy pattern in the real world
Advantages of the Proxy pattern
Comparing the Façade and Proxy patterns
Frequently asked questions
Summary
6. The Observer Pattern – Keeping Objects in the Know Chevron down icon Chevron up icon
6. The Observer Pattern – Keeping Objects in the Know
Introducing Behavioral patterns
Understanding the Observer design pattern
The Observer pattern in the real world
The Observer pattern methods
Loose coupling and the Observer pattern
The Observer pattern – advantages and disadvantages
Frequently asked questions
Summary
7. The Command Pattern – Encapsulating Invocation Chevron down icon Chevron up icon
7. The Command Pattern – Encapsulating Invocation
Introducing the Command pattern
Understanding the Command design pattern
Implementing the Command pattern in the real world
Advantages and disadvantages of Command patterns
Frequently asked questions
Summary
8. The Template Method Pattern – Encapsulating Algorithm Chevron down icon Chevron up icon
8. The Template Method Pattern – Encapsulating Algorithm
Defining the Template Method pattern
The Template Method pattern in the real world
The Template Method pattern – hooks
The Hollywood principle and the Template Method
The advantages and disadvantages of the Template Method pattern
Frequently asked questions
Summary
9. Model-View-Controller – Compound Patterns Chevron down icon Chevron up icon
9. Model-View-Controller – Compound Patterns
An introduction to Compound patterns
The Model-View-Controller pattern
A UML class diagram for the MVC design pattern
The MVC pattern in the real world
Benefits of the MVC pattern
Frequently asked questions
Summary
10. The State Design Pattern Chevron down icon Chevron up icon
10. The State Design Pattern
Defining the State design pattern
A simple example of the State design pattern
Advantages/disadvantages of the State pattern
Summary
11. AntiPatterns Chevron down icon Chevron up icon
11. AntiPatterns
An introduction to AntiPatterns
Software development AntiPatterns
Software architecture AntiPatterns
Summary
Index Chevron down icon Chevron up icon
Index

Recommendations for you

Left arrow icon
Modern CMake for C++
Modern CMake for C++
Read more
May 2024 502 pages
Full star icon 4.6 (11)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $49.99
$9.99 $39.99
$49.99
Layered Design for Ruby on Rails Applications
Layered Design for Ruby on Rails Applications
Read more
Aug 2023 298 pages
Full star icon 4.7 (16)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $49.99
$9.99 $39.99
$49.99
Efficient Algorithm Design
Efficient Algorithm Design
Read more
Oct 2024 360 pages
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $43.99
$9.99 $35.99
$43.99
​Application Lifecycle Management on Microsoft Power Platform
​Application Lifecycle Management on Microsoft Power Platform
Read more
Oct 2024 222 pages
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $44.99
$9.99 $35.99
$44.99
50 Algorithms Every Programmer Should Know
50 Algorithms Every Programmer Should Know
Read more
Sep 2023 538 pages
Full star icon 4.5 (67)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $49.99
$9.99 $39.99
$49.99
Programming APIs with C# and .NET
Programming APIs with C# and .NET
Read more
Nov 2024 166 pages
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $44.99
$9.99 $35.99
$44.99
Learn to Code with Rust
Learn to Code with Rust
Read more
Nov 2024 37hrs 6mins
Video
Video
  • Video Video $9.99
$9.99 $29.99
Asynchronous Programming with C++
Asynchronous Programming with C++
Read more
Nov 2024 424 pages
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $41.99
$9.99 $33.99
$41.99
Fundamentals of Object-Oriented Programming - C++
Fundamentals of Object-Oriented Programming - C++
Read more
Feb 2023 7hrs 6mins
Video
Video
  • Video Video $9.99
$9.99 $29.99
Hands-On Design Patterns with C++
Hands-On Design Patterns with C++
Read more
Jul 2023 626 pages
Full star icon 4.5 (11)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $48.99
$9.99 $39.99
$48.99
Right arrow icon

Customer reviews

Top Reviews
  • Top Reviews
  • Most Recent
Rating distribution
Full star icon Full star icon Half star icon Empty star icon Empty star icon 2.8
(13 Ratings)
5 star 30.8%
4 star 0%
3 star 23.1%
2 star 15.4%
1 star 30.8%
Filter icon Filter
Top Reviews
  • Top Reviews
  • Most Recent

Filter reviews by

maurice ling Mar 22, 2016
Full star icon Full star icon Full star icon Full star icon Full star icon 5
Disclaimer: I am a technical reviewer for this book.Through the entire period serving as technical reviewer for this book, I am impressed with the easy-to-follow style of writing. I had to review the book in chapters across a few months and there is no point in time where I need to wonder if I really understood what the author had to say. As such, I can safely say that this book is well-written and each chapter is contained (there is almost no need to flip back and forth the book to understand the material within any chapter on hand) - quite a remarkable feat for a book.Each chapter is focused on a specific design pattern. The why and how of each pattern is explained in a clear fashion. This makes it easy to read for anyone, both beginners and experienced Python programmers. The materials are even suitable for pre-bedtime leisure reading. Personally, I recommend this to the developers in my own company.
Amazon Verified review Amazon
Govind Karmakar Nov 11, 2018
Full star icon Full star icon Full star icon Full star icon Full star icon 5
A good blend of theory with code snippets. It gives a good start to the folks want to delve into the concepts of design patterns using python.
Amazon Verified review Amazon
Sudhir Chawla May 02, 2016
Full star icon Full star icon Full star icon Full star icon Full star icon 5
With the growing popularity of Python as preferred programming language, the book serves the need to educate readers on the importance of design patterns in python. The author does a very good job by first delving into the basics of OOPs and then gradually introducing the subject of design patterns, all in python 3.5.However reference to python docs could have been included in the book while using some of the more esoteric functions in python. The UML Diagrams mentioned at the beginning of each pattern helps the reader to visualize the hierarchy of objects. The real world examples of all patterns certainly does drive the point home.In short, the book provides concise but well illustrated information about the design pattern and its implementation in python.
Amazon Verified review Amazon
Christian Scheunert Oct 21, 2016
Full star icon Full star icon Full star icon Full star icon Full star icon 5
Short and conclusive pattern description with very nice examples. The layout is not the best (looks like a copy of a web page), however, the content is definitely worth it.
Amazon Verified review Amazon
B Jul 29, 2017
Full star icon Full star icon Full star icon Empty star icon Empty star icon 3
The narrative style the book, at least up to where I've read so far, feels more like a brain dump from a friend to another than a carefully thought out and written book. The author clearly understands the concepts but struggles to explain them.However, my main gripe is with the code examples. They seem to go off at a tangent trying to do something clever (or asinine) instead of focusing on what they're meant to be illustrating.All in all I'm happy with this book, but at the price purchased.
Amazon Verified review Amazon

People who bought this also bought

Left arrow icon
Domain-Driven Design with Golang
Domain-Driven Design with Golang
Read more
Dec 2022 204 pages
Full star icon 4.4 (19)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $44.99
$9.99 $35.99
$44.99
Template Metaprogramming with C++
Template Metaprogramming with C++
Read more
Aug 2022 480 pages
Full star icon 4.6 (14)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $46.99
$9.99 $37.99
$46.99
The Python Workshop Second Edition
The Python Workshop Second Edition
Read more
Nov 2022 600 pages
Full star icon 4.6 (21)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $51.99
$9.99 $41.99
$51.99
Event-Driven Architecture in Golang
Event-Driven Architecture in Golang
Read more
Nov 2022 384 pages
Full star icon 4.9 (11)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $49.99
$9.99 $39.99
$49.99
50 Algorithms Every Programmer Should Know
50 Algorithms Every Programmer Should Know
Read more
Sep 2023 538 pages
Full star icon 4.5 (67)
eBook
eBook
  • eBook eBook $9.99
  • Paperback Paperback $49.99
$9.99 $39.99
$49.99
Right arrow icon

About the authors

Left arrow icon
Profile icon Zlobin
Zlobin
Gennadiy Zlobin works as Lead Software Engineer and Technical Leader in the Russian music service, Zvooq.ru. His current employer is Zvooq Ltd. He has been using Python as the primary language for more than 4 years, enjoying its elegance and power every day. His professional interests include high-load software architectures, good engineering practices, Android OS, and natural language processing. Previously, he worked for the company that had the first search engine in Russia, called Rambler. He was engaged in airline tickets' meta search service and Rambler's index page.
Read more
See other products by Zlobin
Profile icon Giridhar
Giridhar
Chetan Giridhar is a technology leader and an open source evangelist. He is the author of Learning Python Design Patterns, Second Edition, has been an invited speaker at international PyCon conferences, and is an associate editor at the Python Papers journal. He takes keen interest in platform engineering, distributed systems, mobile app development, and real-time cloud applications. You can take a look at his experiments at https://github.com/cjgiridhar and his website https://technobeans.com. In his current role as the chief technology officer, Chetan owns the product strategy and drives technology for CallHub. Prior to CallHub, he was associated with BlueJeans Networks and NetApp, where he worked on cloud, video, and enterprise storage products. Chetan believes that the world is full of knowledge; he's always curious to learn new things and share them with open source community, friends, and colleagues. You can connect with him on LinkedIn at https://www.linkedin.com/in/cjgiridhar/.
Read more
See other products by Giridhar
Right arrow icon
Get free access to Packt library with over 7500+ books and video courses for 7 days!
Start Free Trial

FAQs

How do I buy and download an eBook? Chevron down icon Chevron up icon

Where there is an eBook version of a title available, you can buy it from the book details for that title. Add either the standalone eBook or the eBook and print book bundle to your shopping cart. Your eBook will show in your cart as a product on its own. After completing checkout and payment in the normal way, you will receive your receipt on the screen containing a link to a personalised PDF download file. This link will remain active for 30 days. You can download backup copies of the file by logging in to your account at any time.

If you already have Adobe reader installed, then clicking on the link will download and open the PDF file directly. If you don't, then save the PDF file on your machine and download the Reader to view it.

Please Note: Packt eBooks are non-returnable and non-refundable.

Packt eBook and Licensing When you buy an eBook from Packt Publishing, completing your purchase means you accept the terms of our licence agreement. Please read the full text of the agreement. In it we have tried to balance the need for the ebook to be usable for you the reader with our needs to protect the rights of us as Publishers and of our authors. In summary, the agreement says:

  • You may make copies of your eBook for your own use onto any machine
  • You may not pass copies of the eBook on to anyone else
How can I make a purchase on your website? Chevron down icon Chevron up icon

If you want to purchase a video course, eBook or Bundle (Print+eBook) please follow below steps:

  1. Register on our website using your email address and the password.
  2. Search for the title by name or ISBN using the search option.
  3. Select the title you want to purchase.
  4. Choose the format you wish to purchase the title in; if you order the Print Book, you get a free eBook copy of the same title. 
  5. Proceed with the checkout process (payment to be made using Credit Card, Debit Cart, or PayPal)
Where can I access support around an eBook? Chevron down icon Chevron up icon
  • If you experience a problem with using or installing Adobe Reader, the contact Adobe directly.
  • To view the errata for the book, see www.packtpub.com/support and view the pages for the title you have.
  • To view your account details or to download a new copy of the book go to www.packtpub.com/account
  • To contact us directly if a problem is not resolved, use www.packtpub.com/contact-us
What eBook formats do Packt support? Chevron down icon Chevron up icon

Our eBooks are currently available in a variety of formats such as PDF and ePubs. In the future, this may well change with trends and development in technology, but please note that our PDFs are not Adobe eBook Reader format, which has greater restrictions on security.

You will need to use Adobe Reader v9 or later in order to read Packt's PDF eBooks.

What are the benefits of eBooks? Chevron down icon Chevron up icon
  • You can get the information you need immediately
  • You can easily take them with you on a laptop
  • You can download them an unlimited number of times
  • You can print them out
  • They are copy-paste enabled
  • They are searchable
  • There is no password protection
  • They are lower price than print
  • They save resources and space
What is an eBook? Chevron down icon Chevron up icon

Packt eBooks are a complete electronic version of the print edition, available in PDF and ePub formats. Every piece of content down to the page numbering is the same. Because we save the costs of printing and shipping the book to you, we are able to offer eBooks at a lower cost than print editions.

When you have purchased an eBook, simply login to your account and click on the link in Your Download Area. We recommend you saving the file to your hard drive before opening it.

For optimal viewing of our eBooks, we recommend you download and install the free Adobe Reader version 9.