Building the Web of Things: With examples in Node.js and Raspberry Pi / Edition 1

by Dominique Guinard, Vlad Trifa

Overview

Summary

A hands-on guide that will teach how to design and implement scalable, flexible, and open IoT solutions using web technologies. This book focuses on providing the right balance of theory, code samples, and practical examples to enable you to successfully connect all sorts of devices to the web and to expose their services and data over REST APIs.

Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications.

About the Technology

Because the Internet of Things is still new, there is no universal application protocol. Fortunately, the IoT can take advantage of the web, where IoT protocols connect applications thanks to universal and open APIs.

About the Book

Building the Web of Things is a guide to using cutting-edge web technologies to build the IoT. This step-by-step book teaches you how to use web protocols to connect real-world devices to the web, including the Semantic and Social Webs. Along the way you'll gain vital concepts as you follow instructions for making Web of Things devices. By the end, you'll have the practical skills you need to implement your own web-connected products and services.

What's Inside

• Introduction to IoT protocols and devices
• Connect electronic actuators and sensors (GPIO) to a Raspberry Pi
• Implement standard REST and Pub/Sub APIs with Node.js on embedded systems
• Learn about IoT protocols like MQTT and CoAP and integrate them to the Web of Things
• Use the Semantic Web (JSON-LD, RDFa, etc.) to discover and find Web Things
• Share Things via Social Networks to create the Social Web of Things
• Build a web-based smart home with HTTP and WebSocket
• Compose physical mashups with EVRYTHNG, Node-RED, and IFTTT

About the Reader

For both seasoned programmers and those with only basic programming skills.

About the Authors

Dominique Guinard and Vlad Trifa pioneered the Web of Things and cofounded EVRYTHNG, a large-scale IoT cloud powering billions of Web Things.

Table of Contents

1. From the Internet of Things to the Web of Things
2. Hello, World Wide Web of Things
3. Node.js for the Web of Things
4. Getting started with embedded systems
5. Building networks of Things
6. Access: Web APIs for Things
7. Implementing Web Things
8. Find: Describe and discover Web Things
9. Share: Securing and sharing Web Things

Product Details

ISBN-13:	9781617292682
Publisher:	Manning
Publication date:	06/18/2016
Edition description:	1st Edition
Pages:	344
Product dimensions:	7.30(w) x 9.20(h) x 0.90(d)

About the Author

Dominique Guinard is the CTO and co-founder of EVRYTHNG, a large-scale Web of Things cloud making products smart by connecting them the Web. Dom Guinard got his Ph.D. from ETH Zurich, where he worked on the early concepts of the Web of Things architecture: an open application layer for the Internet of Things. Recently Dom joined the Web of Things Interest Group at W3C with EVRYTHNG as a founding member organization.

Vlad Trifa is co-founder and head of R&D at EVRYTHNG - a new Internet software company providing online profiles, or "Active Digital Identities," for any physical object. He completed his PhD at the Institute for Pervasive Computing at ETH Zurich working on the Web of Things and real-time data sharing, collection, and processing using Web technologies.

Table of Contents

Preface xiii

Acknowledgments xv

About this book xviii

Part 1 Basics of the IoT and the WoT 1

1 From the Internet of Things to the Web of Things 3

1.1 Defining the Internet of Things 4

1.2 Enter the Web of Things 6

Web of Things scenario: connected hotel 6

Comparing IoT and WoT 8

The Internet of Things-a brief history 12

1.3 Use cases-why connected objects? 14

Wireless sensor networks and distributed sensing 14

Wearables and quantified self 16

Smart homes and buildings 17

Smart cities and energy grids 18

Smart manufacturing and Industry 4.0 19

Smart logistics and supply chains 19

Marketing 2.0 21

1.4 The Web of Things-a supercharged Internet of Things 22

Easier to program 23

Open and extensible standards 24

Fast and easy to deploy, maintain, and integrate 24

Loose coupling between elements 25

Widely used security and privacy mechanisms 25

WoT-the shortcomings 26

1.5 Summary 27

2 Hello, World Wide Web of Tings 29

2.1 Meet a Web of Things device 30

The suspect: Raspberry Pi 31

2.2 Exercise 1-Browse a device on the Web of Things 32

Part 1 The web as user interface 32

Part 2 The web as an API 36

So what? 41

2.3 Exercise 2-Polling data from a WoT sensor 42

Part 1 Polling the current sensor value 42

Part 2 Polling and graphing sensor values 43

Part 3 Real-time data updates 44

So what? 45

2.4 Exercise 3-Act on the real world 46

Part 1 Use a form to update text to display 46

Part 2 Create your own form to control devices 48

So what? 50

2.5 Exercise 4-Tell the world about your device 50

So what? 54

2.6 Exercise 5-Create your first physical mashup 54

So what? 57

2.7 Summary 57

3 Node.js for the Web of Things 59

3.1 The rise of JavaScript: from clients to servers to things! 60

Pushing JavaScript to things 61

3.2 Introduction to Node.js 62

Installing Node.js on your machine 63

Your first web server in Node.js 63

Returning sensor data as JSON 65

3.3 Modularity in Node.js 66

Npm-the Node package manager 67

Clean dependencies with package.json and npm 68

Your first Node module 69

3.4 Understanding the Node.js event loop 71

Multithreaded web servers 71

Single-threaded, non-blocking web servers 71

3.5 Getting started with asynchronous programming 73

Anonymous callbacks 74

Named callbacks 77

Control flow libraries 78

3.6 Summary and beyond the book 81

Getting started with embedded systems 83

4.1 The world of embedded devices 84

Devices for hobbyists vs. industrial devices 84

Real-time operating systems vs. Linux 85

Summary and beyond the Pi 87

4.2 Set up your first WoT device-Raspberry Pi 88

Meet the Raspberry Pi 88

Choosing your Pi 89

Shopping list 90

Setting up your Raspberry Pi 91

Connecting to your device 96

4.3 Installing Node.js on the Raspberry Pi 97

Using Git and GitHub on the Pi 99

So what? 99

4.4 Connecting sensors and actuators to your Pi 99

Understanding GPIO ports 100

Working with breadboards and electronic components 100

Accessing GPIOs from Node.js 102

Beyond the book 107

4.5 Summary 108

5 Building networks of Things 109

5.1 Connecting Things 111

Network topologies 111

Network classification models 113

5.2 Networking protocols for Things 115

Spatial considerations 115

Internet protocols and the IoT 116

IoT personal area networks 120

IoT wide area networks 124

So, which one should I choose? 127

5.3 Application protocols for Things 130

ZigBee and Bluetooth application slacks 130

Apple HomeKit and Google Weave 132

Message Queuing Telemetry Transport 132

Constrained Application Protocol 135

So, which one should I use? 135

5.4 The Web of Things architecture 136

Layer 1: Access 136

Layer 2: Find 137

Layer 3: Share 138

Layer 4: Compose 138

Why does the WoT matter? 138

Beyond the hook 139

5.5 Summary 140

Part 2 Building the WoT 141

6 Access: Web APIs for Things 143

6.1 Devices, resources, and web Things 144

Representational Stale Transfer 144

Why do we need a uniform interface? 146

Principle 1 Addressable resources 147

Principle 2 Manipulation of resources through representations 151

Principle 3 Self-descriptive messages 154

Principle 4 Hypermedia as the Engine of Application State 160

Summary-web Things design process 163

6.2 Beyond REST: the real-time Web of Things 163

The WoT needs events! 164

Publish/subscribe 165

Webhooks-HTTP callbacks 166

Comet-hacking HTTP for a real-time web 167

WebSockets 168

The future: from HTTP/1.1 to HTTP/2 172

6.3 Summary 173

7 Implementing web Things 175

7.1 Connecting devices to the web 176

7.2 Direct integration pattern-REST on devices 177

Creating a WoT server 178

Resource design 180

Representation design 186

Interface design 189

Pub/sub interface via WebSockets 191

Summary-direct integration pattern 194

7.3 Gateway integration pattern-CoAP example 194

Running a CoAP server 195

Proxying CoAP via a gateway 196

Summary-gateway integration pattern 198

7.4 Cloud integration pattern-MQTT over EVRYTHNG 199

Set up your EVRYTHNG account 201

Create your MQTT client application 204

Use actions to control the power plug 206

Create a simple web control application 208

Summary-cloud integration pattern 212

7.5 Summary 212

8 Find: Describe and discover web Things 214

8.1 The findability problem 215

8.2 Discovering Things 217

Network discovery 217

Resource discovery on the web 220

8.3 Describing web Things 223

Introducing the Web Thing Model 225

Metadata 227

Properties 227

Actions 229

Things 231

Implementing the Web Thing Model on the Pi 232

Summary-the Web Thing Model 238

8.4 The Semantic Web of Things 239

Linked data and RDFa 239

Agreed-upon semantics: Schema.org 243

JSON-LD 244

Beyond the book 246

8.5 Summary 247

9 Share: Securing and sharing web Things 248

9.1 Securing Things 250

Encryption 101 252

Web security with TLS: the S of HTTPS! 253

Enabling HTTPS and WSS with TLS on your Pi 255

9.2 Authentication and access control 260

Access control with REST and API tokens 260

OAuth: a web authorization framework 263

9.3 The Social Web of Things 265

A Social Web of Things authentication proxy 266

Implementing a Social WoT authentication proxy 269

9.4 Beyond the book 276

9.5 Summary 278

10 Compose: Physical mashups 279

10.1 Building a simple app-automated UI generation 280

A universal user interface for web Things 281

10.2 Physical mashups 288

Boxes and wires mashups for the Physical Web: Node-RFD 289

10.3 Using wizards for physical mashups: IFTTT 295

Pushing intruder alert tweets to a Google spreadsheet 296

Sending requests to a Thing with the Maker Channel 298

Pushing intruder alert tweets to a Google spreadsheet 299

10.4 Beyond the book 300

From simple mashups to big data -mashups 300

A better user experience 301

10.5 Summary 302

Appendix Arduino, BeagleBone, Intel Edison, and the WoT 303

Index 309