This document is the copyrighted first edition of "Introduction to JavaScript Object Notation" by Lindsay Bassett, published in 2015 by O'Reilly Media. It includes a preface and 10 chapters that introduce key concepts about JSON, such as its syntax, data types, schema, security concerns, and use with JavaScript, NoSQL databases, and server-side frameworks. The book provides a comprehensive yet concise overview of JSON for developers to learn how to work with this popular data interchange format.

2. 978-1-491-92948-3
[LSI]
Introduction to JavaScript Object Notation
by Lindsay Bassett
Copyright © 2015 Lindsay Bassett. All rights reserved.
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2015-08-04: First Release
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3. Table of Contents
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
1. What Is JSON?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
JSON Is a Data Interchange Format 1
JSON Is Programming Language Independent 2
Key Terms and Concepts 4
2. JSON Syntax. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
JSON Is Based on JavaScript Object Literals 5
Name-Value Pairs 6
Proper JSON Syntax 7
Syntax Validation 10
JSON as a Document 11
The JSON MediaType 11
Key Terms and Concepts 11
3. JSON Data Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Quick Look at Data Types 13
The JSON Data Types 15
The JSON Object Data Type 16
The JSON String Data Type 17
The JSON Number Data Type 19
The JSON Boolean Data Type 20
The JSON Null Data Type 20
The JSON Array Data Type 21
Key Terms and Concepts 26
iii

4. 4. JSON Schema. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Contracts with Validation Magic 30
Introduction to JSON Schema 31
Key Terms and Concepts 36
5. JSON Security Concerns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
A Quick Look at Client- and Server-Side Relationships 39
Cross-Site Request Forgery (CSRF) 40
Injection Attacks 43
Cross-Site Scripting (XSS) 43
Holes in Security: Architectural Decisions 45
Key Terms and Concepts 46
6. The JavaScript XmlHttpRequest and Web APIs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Web APIs 50
The JavaScript XMLHttpRequest 53
Relationship Woes and Rules About Sharing 57
Cross-Origin Resource Sharing (CORS) 57
JSON-P 58
Key Terms and Concepts 60
7. JSON and Client-Side Frameworks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
jQuery and JSON 64
AngularJS 66
Key Terms and Concepts 71
8. JSON and NoSQL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
The CouchDB Database 74
The CouchDB API 77
Key Terms and Concepts 85
9. JSON on the Server Side. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Serializing, Deserializing and Requesting JSON 88
ASP.NET 88
PHP 92
A Smorgasbord of JSON HTTP Requests 96
Ruby on Rails 97
Node.js 98
Java 98
Key Terms & Concepts 99
iv | Table of Contents

5. 10. Conclusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
JSON as a Configuration File 101
The Big Picture 104
Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
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