Table Of Contentwww.it-ebooks.info
Mastering Web Application
Development with Express
A comprehensive guide to developing production-ready
web applications with Express
Alexandru Vlăduțu
BIRMINGHAM - MUMBAI
www.it-ebooks.info
Mastering Web Application Development with Express
Copyright © 2014 Packt Publishing
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However, Packt Publishing cannot guarantee the accuracy of this information.
First published: September 2014
Production reference: 1180914
Published by Packt Publishing Ltd.
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Birmingham B3 2PB, UK.
ISBN 978-1-78398-108-3
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Cover image by Goldie Jason (goldie.jason@gmail.com)
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Credits
Author Project Coordinator
Alexandru Vlăduțu Swati Kumari
Reviewers Proofreaders
Johan Borestad Ameesha Green
Mohit Goenka Maria Gould
Arjunkumar Krishnamoorthy Paul Hindle
Dave Poon Jonathan Todd
Commissioning Editor
Indexers
Ashwin Nair
Rekha Nair
Priya Sane
Acquisition Editor
James Jones
Graphics
Content Development Editors Abhinash Sahu
Nadeem N. Bagban
Poonam Jain Production Coordinator
Conidon Miranda
Technical Editors
Novina Kewalramani Cover Work
Pratik More Conidon Miranda
Copy Editors
Mradula Hegde
Dipti Kapadia
Insiya Morbiwala
Alfida Paiva
Stuti Srivastava
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About the Author
Alexandru Vlăduțu is a full-time JavaScript developer based in Bucharest,
Romania. He started creating applications with PHP about 5 years ago, but
after finding out about server-side JavaScript with Node.js, he has never had to
switch technologies again. You may have seen him answering questions on Stack
Overflow under the nickname alessioalex, where he is among the top three
overall answerers for tags such as Node.js, Express, Mongoose, and Socket.IO. By
day, he battles cross-browser compatibility issues, but by night, he brings together
embedded databases, servers, and caching layers in single applications using the
good parts of JavaScript. Apart from the geeky stuff, he enjoys spending time with
his wife.
The first time I saw the video of Ryan Dahl presenting Node
at JS Conf 2009, I was amazed. I have been fanatically working
with Node ever since, and Ryan deserves credit for this.
I would like to thank TJ Holowaychuk for authoring Express,
and the Node community for being friendly, helpful, and
extremely active.
While writing this book, I had invaluable feedback from the
reviewers as well as the Packt Publishing team; so thanks a
lot everybody!
Most importantly, I would like to thank my wife, Diana, for her
support, encouragement, and patience.
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About the Reviewers
Johan Borestad lives and works in Stockholm, Sweden. With 10 years of
experience in several successful start-ups, he has built up a deep knowledge of the
industry. As a very outgoing and pragmatic perfectionist, he is constantly seeking
new ways to improve himself and his team members. While always striving to
deliver world-class products, Johan also enjoys telling bad jokes and drinking way
too much coffee.
He is currently working at Klarna, building the Klarna Checkout. It is a multimarket,
single-page application that is revolutionizing the e-commerce business currently.
Its strong focus on usability and simplifying the buying process has made it a huge
success in the Nordics and Germany. He has previously also reviewed Express Web
Application Development, Packt Publishing.
I'd like to give my warmest thank-you to my lovely family as well as
to Klarna and my teammates who helped me during tough times.
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Mohit Goenka is a Software Developer in the Yahoo! Mail team. He graduated
from the University of Southern California (USC) with a Master of Science degree in
Computer Science. His thesis emphasized game theory and human behavior concepts
as applied in real-world security games. He also received an award for academic
excellence from the Office of International Services at the University of Southern
California. He has showcased his presence in various realms of computers, including
artificial intelligence, machine learning, path planning, multiagent systems, neural
networks, computer vision, computer networks, and operating systems.
During his tenure as a student, Mohit won multiple competitions, cracked codes,
and presented his work on the Detection of Untouched UFOs to a wide range of
audiences. Not only is he a software developer by profession but coding is also
his hobby. He spends most of his spare time learning about emerging trends
and grooming his technical skills.
What adds a feather to his cap are Mohit's poetic skills. Some of his poems are
part of the University of Southern California Libraries archive under the cover
of The Lewis Carroll Collection. In addition to this, he has made significant
contributions by volunteering his time to serve the community.
Arjunkumar Krishnamoorthy is a Principal Engineer with Causeway
Technologies in Bengaluru, India. He is well-versed in Java, JavaScript, Node.js,
and Angular.js, among others. He has contributed to open source projects. He
is passionate about programming, research, and open source technologies.
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Dave Poon is a UX/UI designer, web developer, and entrepreneur based in
Sydney. He started his career as a freelance graphic designer and web designer in
1998 and worked with web development agencies and medium-size enterprises.
After graduating from Central Queensland University with a degree in Multimedia
Studies and a Master's degree in IT, he began his love affair with Drupal and works
for a variety of companies that use Drupal. Now, he is evangelizing good user
experience and interaction design practices to start-ups and enterprises.
Currently, he is a Design Lead at Suncorp, one of the biggest financial institutions
in Australia. He is also the cofounder of Erlango (http://erlango.com), a digital
product development and design start-up, located in Sydney and Hong Kong,
that creates user-centered digital products and tools for designers and users.
He is the author of Drupal 7 Fields/CCK Beginner's Guide, Packt Publishing. He
is also the technical reviewer of Drupal Intranets with Open Atrium, Tracy Smith,
Packt Publishing, and Advanced Express Web Application Development, Andrew Keig,
Packt Publishing.
I would like to thank my wife, Rita, for her endless patience and
support. Without her, whatever I do would be meaningless.
I would also like to thank my father for his continued
encouragement.
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Table of Contents
Preface 1
Chapter 1: Diving into Express 7
The best parts of Express 7
Comparing Express with other frameworks 8
Goal 8
Conventions 9
Databases 9
Views 9
Overall 9
Use cases 10
Complex applications with heavy I/O bound operations 10
Single-page applications 10
Reusable applications 11
Code sharing between the server and the client 11
A base to create more complex frameworks 11
Bad use cases 12
Express into the wild 12
The application structure 13
Group files by features 13
Model-View-Controller 14
Developing a real MVC application 15
Summary 32
Chapter 2: Component Modularity Using Middleware 33
Connecting middleware 33
The functionality of middleware 34
Pushing items to an array 36
Looking at the execution flow using logs 36
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