Introduction 1
About This Book 1
Foolish Assumptions 2
Icons Used in This Book 2
Beyond the Book 2
Where to Go from Here 3
Part 1: Getting to Know Blockchain and Ethereum 5
Chapter 1: Introducing Ethereum 7
Describing Blockchain Technology 8
Introducing Ethereum 10
Exploring Ethereum’s Consensus, Mining, and Smart Contracts 11
Buying, Spending, and Trading Ether 13
Getting Started with DAO and ICO 16
Exploring the Ethereum Ecosystem 17
Delving into Development Tools 18
Building Blockchain Apps 18
Chapter 2: Learning about Blockchain 21
Exploring Distributed Applications 22
Digging into distributed processing 22
Exploring problems with distributed processing 24
Presenting some solutions to distributed processing problems 27
Examining the Bitcoin Solution to the Distributed Dilemma 28
Describing Blockchains 30
Examining blockchain details 30
Protecting blockchain visibility 31
Building Blockchains 33
Agreeing to add blocks 33
Making blocks immutable 34
Reviewing the building process 35
Keeping all blockchains consistent 35
Understanding How Blockchains and Databases Store Data Differently 36
Storing data in a traditional database 36
Storing data in a blockchain 38
Effectively Using Blockchains 39
Transferring value without trust 39
Reducing transaction costs by eliminating middlemen 39
Increasing efficiency through direct interaction 40
Maintaining complete transaction history 40
Increasing resilience through replication 41
Providing transparency 41
Chapter 3: Exploring Use Cases for Ethereum 43
Diving Into Ethereum Applications 44
Exploring Financial Services 45
Banking 46
Creating Ethereum escrow applications 48
Examining ICOs 48
Establishing Digital Identity Management 49
Managing individual and device identities 50
Reducing fraud and identity theft 50
Examining the ERC-725 standard and beyond 51
Examining Industry Applications 51
Healthcare 52
Energy 52
Supply chain 53
Enabling Effective Governance 54
Tax payment 54
Government spending 55
Voting 55
Policy development 55
Notary 56
Part 2: Setting Up Your Ethereum Development Environment 57
Chapter 4: Examining the Ethereum Ecosystem and Development Lifecycle 59
Exploring the Ethereum Blockchain Block Structure 60
Describing Smart Contracts 64
Introducing Solidity, the Language of Smart Contracts 66
Working with the Ethereum Virtual Machine 67
Fueling Your Code with Gas 68
Surveying Tools for Developing, Testing, and Deploying Ethereum Apps 69
Ethereum blockchain client 70
Development and testing blockchain 71
Compiler and testing framework 72
Source code editor/IDE 72
Describing the Ethereum Development Lifecycle 73
Introducing Smart Contract Development Tools 74
Chapter 5: Getting and Configuring Ethereum Development Tools 77
Examining Why Multiple Ethereum Development Tools are Available 78
Downloading, Installing, and Configuring All the Pieces 79
Installing the blockchain client 79
Installing the test blockchain 83
Installing the testing environment 86
Installing the IDE 91
Chapter 6: Establishing an Ethereum Wallet 95
Unlocking the Secrets of an Ethereum Wallet 96
Examining the Types of Ethereum Wallets 96
Sorting out software wallets 97
Handling hardware wallets 99
Perusing paper wallets 99
Choosing an Ethereum Wallet 100
Software wallets 100
Hardware wallets 102
Paper wallets 103
Installing MetaMask, an Ethereum Wallet 104
Part 3: Building Ethereum Distributed Blockchain Apps 107
Chapter 7: Building Your First Ethereum Apps 109
Validating Your Ethereum Development Environment 110
Creating a Truffle project 110
Editing the Truffle config file 111
Exploring the Ganache Test Environment 113
Designing Simple Smart Contracts 115
Coding Your First Smart Contract 116
Running Your First Smart Contract 118
Writing your code 118
Compiling your code 119
Deploying your code 120
Invoking your code’s functions 122
Paying as You Go 124
Chapter 8: Learning about Smart Contracts 125
Introducing Supply Chain and Common Challenges 126
Describing supply chain 126
Explaining difficulties when implementing a supply chain 127
Examining How Blockchain Can Help Resolve Supply Chain Problems 128
Describing a Blockchain Supply Chain Solution 129
Paying for supply chain services 129
Managing assets on the supply chain 130
Digging into Solidity 132
Describing Basic Smart Contract Syntax 133
Declaring valid compiler version 134
Commenting your code 134
Importing external code 135
Defining your smart contracts 135
Handling Data in Solidity 136
Learning about Computation and Gas 140
Exploring Access Modes and Visibility of Smart Contract Functions and Data 142
Controlling Execution Flow 144
Handling Errors and Exceptions 145
Chapter 9: Writing Your Own Smart Contracts with Solidity 147
Reviewing Supply Chain Design Specification 148
Payment token smart contract 149
Supply chain smart contract 150
Creating New Smart Contracts 151
ERC-20 token interface 153
ERC-20 token smart contract 154
Supply chain smart contract 155
Coding Primary Functions 157
ERC-20 token functions 157
Supply chain functions 160
Using Events 163
Defining events 165
Triggering events 166
Introducing Ownership 168
Designing for Security 170
Implementing Minimal Functionality 171
Part 4: Testing and Deploying Ethereum Apps 173
Chapter 10: Testing Ethereum Apps 175
Understanding Ethereum dApp Testing 176
Writing tests from the beginning 176
Choosing the right test blockchain 176
Learning the steps in the testing lifecycle 177
Testing for software quality 177
Deploying a dApp to a Test Ethereum Blockchain 178
Telling Truffle to use the Ganache blockchain 178
Deploying your code to the Ganache blockchain 180
Writing Tests for Ethereum dApps 181
Testing using the command line 181
Writing test cases in JavaScript 185
Logging and Handling Errors 187
Handling errors in Solidity 188
Logging activity in smart contracts 189
Fixing Bugs in a dApp 190
Chapter 11: Deploying and Maintaining Ethereum Apps 191
Test Blockchain Options versus Live Blockchains 192
Testing with the Ganache blockchain 192
Deploying your code to other test blockchains 193
Anticipating Differences in Live Environments 195
Preparing Your Configuration for Deploying to Different Networks 196
Deploying a dApp 198
Getting enough ether 199
Compiling your code 203
Deploying your code 203
Chapter 12: Integrating Non-Blockchain Apps with Ethereum 205
Comparing Blockchain and Database Storage 206
Locating control 207
Imposing data format 207
Updating data 207
Optimizing performance 208
Protecting confidentiality 208
Paying for storage 208
Providing integrity and transparency 209
Protecting resilience 209
Contrasting Execution and Flow in Blockchain dApps and Traditional Applications 210
Designing Goals for Incorporating Blockchain into an Existing Application 211
Using existing smart contracts 213
Developing your own smart contracts 213
Identifying Interface Data and Transaction Requirements 214
Creating or Modifying Contracts to Provide Data Interface 215
Testing Integrated dApps 215
Deploying Integrated dApps 216
Part 5: The Part of Tens 219
Chapter 13: Ten Free Ethereum Resources 221
Exploring Alternative Ethereum Development Frameworks 222
Managing you development with Populus 222
Exploring Ethereum blockchain containers with Cliquebait 222
Selecting a Free Integrated Development Environment 223
Developing Solidity code with Atom 223
Going online with Remix 224
Keeping it simple with EthFiddle 224
Exploring Ethereum Clients and APIs 226
Swapping your Ethereum client to Parity 226
Interacting with Ethereum by using Web3.js 226
Focusing on Wallets and Security 227
Protecting your crypto-assets in Mist 227
Securing your dApps with OpenZeppelin 228
Learning More About Developing Ethereum dApps 228
Chapter 14: Ten Design Principles for Distributed Blockchain Apps 229
Designing for Trust 230
Enforcing Consistency 230
Removing Doubt through Transparency 232
Providing Feedback, Guidance, and Setting Expectations 233
Handling Mistakes with Class 233
Designing Functions that Focus on User Actions, Not Data 234
Storing Data Based on User Actions, Not Data Structures 235
Keeping It Simple 236
Expecting Blockchain Access to Be Expensive 236
Staying Out of the User’s Way 237
Chapter 15: Top Ten Ethereum Projects 239
Predicting Future Events with Gnosis 240
Crowdsourcing Event Predictions in Augur 240
Managing Decentralized Organizations with Aragon 241
Breeding and Collecting Cryptokitties 241
Exchanging Tokens with IDEX 242
Creating Your Digital Identity with uPort 243
Sharing Your Thoughts on the Blockchain with EtherTweet 243
Searching for Jobs with EthLance 244
Using TenX to Pay with Cryptocurrency 245
Buying and Selling Computing Power with Golem 246
Index 247
