The document provides an introduction to Ethereum smart contracts, detailing their conceptual and technical definitions along with how to write them using the Solidity programming language. It outlines smart contract tooling, best practices for security and performance, and showcases the integration of smart contracts with decentralized applications (dApps). Additionally, it includes resources for further learning and practical examples for hands-on experience.

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ArcBlock Technical Learning Series
Introduction to Ethereum Smart Contract

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Introduction to Ethereum Smart Contract
Shijun 20180927

3. Big Picture
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4. Agenda
What is Smart
Contract?
How to write Smart
Contract?
Smart Contract
Tooling?
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Smart Contract Best
Practice?

5. Before Dive Into Smart Contract

6. Core Concepts of Blockchain
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7. Ethereum Network = Distributed Network
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8. What Is Smart Contract?

9. What is Smart Contract? (Conceptual)
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source: https://github.com/Overtorment/awesome-smart-contracts

10. What is Smart Contract? (Technical)
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source: https://solidity.readthedocs.io/en/v0.4.24/introduction-to-smart-contracts.html
Contract = Account Controlled By Immutable Code

11. Contract Account vs. User Account
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12. From Contract Source to Contract Account?
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13. Contract Source & Contract Account
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14. How To Write Smart Contract?

15. Solidity Programming Language
๏ Contract oriented, influenced by C++/JS/Python
๏ Statically typed, support inheritance
๏ Source file has .sol extension
๏ Compile to bytecode and run in EVM
๏ Javascript similar syntax (not that similar)
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16. Solidity 101: Primitive Types
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17. Solidity 101: Reference Types
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18. Solidity 101: Functions
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Assertions Modifiers

19. Function Call vs. Transaction
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20. Solidity 101: Global Variables/Fns
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block util fns

21. Demo1
Smart Contract Hello World (Remix: Bytecode + ABI)
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22. Smart Contract Tooling?

23. Code Editor
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Remix VSCode + Node.js
• Rapid contract prototyping
• Testing with existing instance
• Deploy to any valid network
• Mange code using Git
• Save compile/deploy to file
• Automate things
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24. Debug/Inspection
๏ Block Explorer
• etherscan.io
• rinkeby.etherscan.io
• ropsten.etherscan.io
• kovan.etherscan.io
๏ Remix
• Debugger mode
• Transaction Log
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25. Testnet/Nodes
๏ Ethereum official testnet (real latency)
• rinkeby
• ropsten
• kovan
๏ In memory testnet (low latency)
• ganache-cli
• remix javascript vm
๏ Infura.io nodes
• require registration
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26. Funding for Testing
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Faucet Builtin Unlocked
• Rinkeby Faucet
• Ropsten Faucet
• Kovan Faucet
• Ganache-cli
• Remix in memory node

27. Transaction Sign/Send
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GUI SDK
• Metamask • Javascript: web3.js
• Java: web3j
• Swift: web3.swift

28. Framework: truffle
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29. Demo2
Creating ABT Token Using Remix + Metamask + Rinkeby
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30. Smart Contract Best Practice?

31. Considerations need to write good Contract
๏ Security
• Overflow, using SafeMath library
• Identity check and assertion, using function modifiers
๏ Performance
• Design storage carefully
• Avoid computation intensive contract code: loops
๏ Engineering
• Do automated tests
• Make code modular
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32. Demo3
Security practices in ArcBlock Token
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33. Where To Go From Here?

34. Smart Contract + DApp = Awesome
๏ What is DApp?
• End-user app that interacts with contract
• An interface that read/render/update contract data
• Can be in form of Web/Native/Desktop App
• Can be SPA with only blockchain backend
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35. Resources From Community
๏ Official documentation
• Solidity
• web3.js 1.x
๏ Awesome series
• BlockchainLabsNZ/awesome-solidity
• cjgdev/awesome-smart-contracts
• JoinColony/awesome-web3
• fivedogit/solidity-baby-steps
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36. Resources From Me
๏ Contract + DApp Examples
• Lottery App: wangshijun/ethereum-lottery-dapp
• ICO DApp (Nuxt.js): wangshijun/ethereum-dapp-nuxt
• ICO DApp (Next.js): wangshijun/ethereum-contract-workflow
๏ 掘金小册
• 《从 0 到 1 构建基于以太坊智能合约的 ICO DApp》
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七折优惠码：shijunvip
Get your hands dirty and build something! 😆

37. Q&A

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