AngularJS Services: Design, build, and test services to create a foundation for your AngularJS applications

153 Pages·2014·1.055 MB·English

by  Jim Lavin

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AngularJS Services
Design, build, and test services to create a solid
foundation for your AngularJS applications
Jim Lavin
BIRMINGHAM - MUMBAI
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AngularJS Services
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First published: August 2014
Production reference: 1140814
Published by Packt Publishing Ltd.
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ISBN 978-1-78398-356-8
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Cover image by Ádám Plézer ([e-mail])
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Credits
Author Project Coordinator
Jim Lavin Neha Bhatnagar
Reviewers Proofreaders
Ruy Adorno Maria Gould
Mike McElroy Ameesha Green
JD Smith
Indexer
Tejal Soni
Acquisition Editor
Joanne Fitzpatrick
Production Coordinators
Melwyn D'sa
Content Development Editor
Anila Vincent Alwin Roy
Technical Editors Cover Work
Pankaj Kadam Melwyn D'sa
Aman Preet Singh
Copy Editors
Janbal Dharmaraj
Karuna Narayanan
Alfida Paiva
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About the Author
Jim Lavin has been involved in software development for the past 30 years. He
is currently the CTO for one of the leading service providers of online ordering for
restaurants where his team uses AngularJS as a core part of their service offerings.
He is the coordinator of the Dallas/Fort Worth area's AngularJS meetup group,
and routinely gives presentations on AngularJS to other technology groups in the
Dallas/Fort Worth area.
I'd like to acknowledge all the people who have provided the
inspiration and support that made this book a reality.
To my father and mother, who taught me that there are no
limitations in life, and that you can do anything as long as you are
willing to put in the concentration and hard work to see it to the end.
To my daughter, who would always help me get off the fence and
make a decision by saying, "That sounds cool! Go for it!"
To my team at work, who embraced the notion of rewriting our
application with AngularJS with such enthusiasm that we did the
impossible in a matter of months.
And finally, to the AngularJS community, which has been a great
part of my inspiration since I've adopted AngularJS. All their blog
posts, videos, questions, and answers have helped to accelerate the
adoption of AngularJS at an amazing rate, making me proud to be a
part of their growing community.
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About the Reviewers
Ruy Adorno is a senior front-end developer with more than 10 years of experience
working in web development, application interfaces, and user experience. You can
get to know more about him on his personal website http://ruyadorno.com.
Mike McElroy is a longtime fan, booster, and contributor to the AngularJS
community. He originally met the author through the AngularJS community on
Google+ while doing a series of hangouts on AngularJS. He worked with AngularJS
professionally, shortly after it emerged from the beta period, and has continued to be
involved in the community to this day. He currently works for DataStax, developing
the UI for their OpsCenter product, and lives in Columbus, Ohio, with his wife and
menagerie of animals.
JD Smith is a front-end architect with 15 years of consulting experience, ranging
from small businesses to Fortune 500 companies. He enjoys working on large
JavaScript applications and coming up with innovative improvements.
In addition to consulting work, he runs a boutique staffing firm, UI Pros, with the
goal of matching the best developers to the best jobs. Contact him at www.uipros.
com or send an e-mail to [e-mail].
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Table of Contents
Preface 1
Chapter 1: The Need for Services 7
AngularJS best practices 8
Responsibilities of controllers 8
Responsibilities of directives 9
Responsibilities of services 10
Summary 11
Chapter 2: Designing Services 13
Measure twice, and cut once 13
Defining your service's interface 13
Focus on the developer, not yourself 14
Favor readability over brevity 14
Limit services to a single area of responsibility 14
Keep method naming consistent 15
Keep to the top usage scenarios 15
Do one thing only 15
Document your interface 15
Designing for testability 16
Law of Demeter 16
Pass in required dependencies 17
Limiting constructors to assignments 20
Use promises sparingly 21
Services, factories, and providers 22
Structuring your service in code 28
Configuring your service 31
Summary 32
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Table of Contents
Chapter 3: Testing Services 33
The basics of a test scenario 33
Loading your modules in a scenario 35
Mocking data 36
Mocking services 38
Mocking services with Jasmine spies 40
Handling dependencies that return promises 42
Mocking backend communications 45
Mocking timers 47
Summary 48
Chapter 4: Handling Cross-cutting Concerns 49
Communicating with your service's consumers using patterns 49
Managing user notifications 54
Logging application analytics and errors 61
Authentication using OAuth 2.0 66
Summary 69
Chapter 5: Data Management 71
Models provide the state and business logic 71
Implementing a CRUD data service 75
Caching data to reduce network traffic 79
Transforming data in the service 82
Summary 87
Chapter 6: Mashing in External Services 89
Storing events with Google Calendar 89
Using Google Tasks to build a brewing task list 94
Tying the Google Calendar and task list together 98
Summary 105
Chapter 7: Implementing the Business Logic 107
Encapsulating business logic in models 108
Encapsulating business logic in services 111
Models or services, which one to use? 113
Controlling a view flow with a state machine 114
Validating complex data with a rules engine 120
Summary 123
Chapter 8: Putting It All Together 125
Wiring in authentication 126
Displaying notifications and errors 126
Controlling the application flow 127
[ ii ]
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Table of Contents
Displaying data from external services 128
Building and calculating the recipe 130
Messaging is the heart of the application 132
Summary 132
Index 135
[ iii ]
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