Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
スマートコントラクトプログラミング / Smart Contract Programming
Search
Kenji Saito
PRO
October 30, 2023
Technology
0
120
スマートコントラクトプログラミング / Smart Contract Programming
2023年10月30日(月)、慶應義塾大学大学院メディアデザイン研究科「サービスデザインプロジェクト B」2023秋で使用したスライドです。
Kenji Saito
PRO
October 30, 2023
Tweet
Share
More Decks by Kenji Saito
See All by Kenji Saito
FinTech 3-4 : Internet Technology and Governance
ks91
PRO
0
19
民主主義と博愛(Humanitarianism) / Democracy and Humanitarianism
ks91
PRO
0
1
ブロックチェーン概論 / Introduction to Blockchain
ks91
PRO
0
6
ブロックチェーンと分散ファイナンス概論 / Introduction to Blockchain and Decentralized Finance
ks91
PRO
0
47
Proof of Authenticity of General IoT Information with Tamper-Evident Sensors and Blockchain
ks91
PRO
0
5
FinTech 1-2 : Overview of FinTech
ks91
PRO
0
14
デジタルトランスフォーメーションと民主主義 / Digital Transformation and Democracy
ks91
PRO
0
19
We Never Took the Kobayashi Maru Test Until Now. What Do You Think of Our Solutions? — Journeys of the Mind Through a No-Win Game
ks91
PRO
0
24
思いつきが武器になる:研究というゲームを始めよう / Ideas Are Your Equipments : Let the Game of Research Begin!
ks91
PRO
0
79
Other Decks in Technology
See All in Technology
Oracle Cloud Infrastructure:2025年9月度サービス・アップデート
oracle4engineer
PRO
0
450
Modern_Data_Stack最新動向クイズ_買収_AI_激動の2025年_.pdf
sagara
0
220
GopherCon Tour 概略
logica0419
2
190
組織観点からIAM Identity CenterとIAMの設計を考える
nrinetcom
PRO
1
180
How to achieve interoperable digital identity across Asian countries
fujie
0
120
いま注目しているデータエンジニアリングの論点
ikkimiyazaki
0
600
成長自己責任時代のあるきかた/How to navigate the era of personal responsibility for growth
kwappa
3
280
生成AI_その前_に_マルチクラウド時代の信頼できるデータを支えるSnowflakeメタデータ活用術.pdf
cm_mikami
0
120
研究開発部メンバーの働き⽅ / Sansan R&D Profile
sansan33
PRO
3
20k
Flaky Testへの現実解をGoのプロポーザルから考える | Go Conference 2025
upamune
1
430
自動テストのコストと向き合ってみた
qa
0
180
extension 現場で使えるXcodeショートカット一覧
ktombow
0
210
Featured
See All Featured
Optimising Largest Contentful Paint
csswizardry
37
3.4k
Fireside Chat
paigeccino
40
3.7k
Raft: Consensus for Rubyists
vanstee
139
7.1k
The Success of Rails: Ensuring Growth for the Next 100 Years
eileencodes
46
7.6k
Dealing with People You Can't Stand - Big Design 2015
cassininazir
367
27k
A Modern Web Designer's Workflow
chriscoyier
697
190k
The MySQL Ecosystem @ GitHub 2015
samlambert
251
13k
Bash Introduction
62gerente
615
210k
Reflections from 52 weeks, 52 projects
jeffersonlam
352
21k
How to Think Like a Performance Engineer
csswizardry
27
2k
GitHub's CSS Performance
jonrohan
1032
460k
Building a Modern Day E-commerce SEO Strategy
aleyda
43
7.7k
Transcript
generated by Stable Diffusion XL v1.0 B 2023 3 (
) B 2023 — 3 — 2023-10-30 – p.1/66
https://speakerdeck.com/ks91 ( ) ( ) Discord Discord ( / /
) Zoom URL ( ) B 2023 — 3 — 2023-10-30 – p.2/66
( ) 1 10 16 • 2 10 23 •
3 10 30 • 4 11 6 5 11 13 1 6 11 20 2 7 11 27 8 12 4 Discord B 2023 — 3 — 2023-10-30 – p.3/66
Ethereum macOS (Ventura 13.6) + Homebrew Linux (Ubuntu 22.04) (x86/AMD64
and ARM) macOS + Lima (Linux Machines) mac M1/M2 (Apple )(ARM) x86/AMD64 Windows 11 + Windows Subsystem for Linux (Ubuntu ) Ethereum solidity brownie B 2023 — 3 — 2023-10-30 – p.4/66
macOS : Homebrew (Apple macOS ) UNIX macOS Lima Homebrew
brew Apple brew ( ) brew https://github.com/homebrew/install Path : https://zenn.dev/tet0h/articles/a92651d52bd82460aefb B 2023 — 3 — 2023-10-30 – p.5/66
macOS : Rosetta 2 Apple x86/AMD64 ( ) $ softwareupdate
–install-rosetta B 2023 — 3 — 2023-10-30 – p.6/66
macOS : Lima macOS Linux ( ) https://github.com/lima-vm/lima QEMU (
) Rosetta 2 Apple x86/AMD64 brew $ brew install lima Ubuntu 22.04 (x86/AMD64) “kmd.yaml” $ limactl start kmd.yaml B 2023 — 3 — 2023-10-30 – p.7/66
macOS : Lima Linux (Ubuntu) x86_64 $ limactl list Linux
(exit ) $ limactl shell kmd Linux limactl list STATUS Stopped limactl start kmd “.lima” diffdisk 100GB B 2023 — 3 — 2023-10-30 – p.8/66
Solidity Ethereum ( ) http://solidity.readthedocs.io/en/latest/installing-solidity.html Linux (on Windows) “sudo apt”,
macOS “brew” Linux ARM git clone dependencies solc 0.8.21 (10/16 ) $ solc --version brownie py-solc-x solc (dependencies) ( solc py-solc-x ) B 2023 — 3 — 2023-10-30 – p.9/66
Ganache Ethereum RPC npm ( ) macOS https://qiita.com/kyosuke5_20/items/c5f68fc9d89b84c0df09 Linux https://qiita.com/seibe/items/36cef7df85fe2cefa3ea
npm Ganache $ sudo npm install -g ganache B 2023 — 3 — 2023-10-30 – p.10/66
Python3 ( Python3.9 ) macOS $ brew install
[email protected]
Linux
$ sudo add-apt-repository ppa:deadsnakes/ppa $ sudo apt update $ sudo apt install python3.9 python3.9-dev python3.9-venv python3.9-tk B 2023 — 3 — 2023-10-30 – p.11/66
macOS : . . . macOS wget brew dyld: Library
not loaded: /usr/local/opt/gettext/lib/libintl.8.dylib $ brew uninstall --force gettext $ brew install gettext B 2023 — 3 — 2023-10-30 – p.12/66
Python (venv) macOS (Linux python3 ) ‘python3.9’ ‘python3’ $ python3.9
-m venv bbc2env $ source bbc2env/bin/activate (bbc2env) $ pip install -U pip bbc2env ( BBc-2 ) ( ) (bbc2env) $ deactivate B 2023 — 3 — 2023-10-30 – p.13/66
Brownie Python Ethereum https://eth-brownie.readthedocs.io Brownie $ pip install eth-brownie version
1.19.3 (10/16 ) PyYAML $ pip install "cython<3.0.0" wheel && pip install pyyaml==5.4.1 --no-build-isolation B 2023 — 3 — 2023-10-30 – p.14/66
$ brownie init ( ERC-20 ) $ brownie bake token
$ cd token B 2023 — 3 — 2023-10-30 – p.15/66
contracts (macOS Linux (x86/AMD64) ) $ brownie compile Linux (ARM)
(AMD64 ) $ python # >>> import solcx >>> solcx.compile_solc(’0.6.12’) # >>> quit() /tmp ∼/.solcx/solc-v0.6.12 ( ) $ pytest tests B 2023 — 3 — 2023-10-30 – p.16/66
Brownie $ brownie console Python >>> len(accounts) 10 >>> accounts[0].balance()
100000000000000000000 >>> quit() B 2023 — 3 — 2023-10-30 – p.17/66
Ethereum Görli B 2023 — 3 — 2023-10-30 – p.18/66
infura.io Brownie https://infura.io SIGN UP PROJECT ID infura Ethereum API
infura . . . infura.io PROJECT ID WEB3_INFURA_PROJECT_ID PROJECT ID (∼/.bash_profile ) $ export WEB3_INFURA_PROJECT_ID= PROJECT ID B 2023 — 3 — 2023-10-30 – p.19/66
G¨ orli ETH brownie console Görli >>> network.disconnect() >>> network.connect(’goerli’)
>>> len(accounts) 0 >>> accounts.add() mnemonic: ’ ( )’ <LocalAccount object ’ 16 ’> >>> accounts[0].private_key 16 >>> quit() Görli Testnet ETH Faucet ETH https://goerlifaucet.com ( ) ( ) 0.001 ETH Görli ETH B 2023 — 3 — 2023-10-30 – p.20/66
G¨ orli ETH brownie console Görli ETH >>> network.disconnect() >>>
network.connect(’goerli’) >>> len(accounts) 0 >>> accounts.add( 16 ) <LocalAccount object ’ 16 ’> >>> accounts[0].balace() ETH >>> quit() ( ) ETH >>> accounts[0].transfer(accounts[1], "0.01 ether") B 2023 — 3 — 2023-10-30 – p.21/66
Ethereum B 2023 — 3 — 2023-10-30 – p.22/66
Ethereum Vitalik Buterin, “Ethereum White Paper: A NEXT GENERATION SMART
CONTRACT & DECENTRALIZED APPLICATION PLATFORM” 12 (= ) = ⇒ → Dapps ( / / ) B 2023 — 3 — 2023-10-30 – p.23/66
( ) B 2023 — 3 — 2023-10-30 – p.24/66
. . . B 2023 — 3 — 2023-10-30 –
p.25/66
vs. Ethereum (Ether ) 13 13 B 2023 — 3
— 2023-10-30 – p.26/66
= run B 2023 — 3 — 2023-10-30 – p.27/66
Ether Ethereum EOA : Externally-Owned Account ( ) Ether EVM
EVM B 2023 — 3 — 2023-10-30 – p.28/66
EVM : Ethereum Virtual Machine ঢ়ଶ ֎෦ΞΫλʔ ΞΧϯτ &7. ίʔυ
&UIFSˠ(BT ىಈ ίϯτϥΫτ ϝοηʔδ͔ɺ৽͍ࣗ͠ಈΦϒδΣΫτ ΞΧϯτؒͰΓऔΓ͞ΕΔσʔλ&UIFS ετϨʔδ ঢ়ଶ` τϥϯβΫγϣϯ ηοτ σδλϧॺ໊ &7. ਓؒͱ͔ ࣗಈ ΦϒδΣΫτ Gas ( ( )) . . . B 2023 — 3 — 2023-10-30 – p.29/66
EVM : : ← : Solidity — JavaScript LLL —
Lisp Vyper — Python Fe — Vyper Rust ← NEW! Solidity Vyper Python B 2023 — 3 — 2023-10-30 – p.30/66
Solidity ( ) pragma solidityˆ0.7.0; contract IndivisibleAsset { /* */
string public _name; string public _symbol; uint256 public _quantity; address public _owner; constructor(string memory name, string memory symbol, uint256 quantity) public { _name = name; _symbol = symbol; _quantity = quantity; _owner = msg.sender; } function transfer(address to) public returns (bool) { require (_owner == msg.sender); _owner = to; return true; } } B 2023 — 3 — 2023-10-30 – p.31/66
( , ) (constructor) (deploy) = ( ) ( )
ETH Trusted Actor Model B 2023 — 3 — 2023-10-30 – p.32/66
Ethereum B 2023 — 3 — 2023-10-30 – p.33/66
(1) : ERC20 $ brownie bake token B 2023 —
3 — 2023-10-30 – p.34/66
pragma solidity ˆ0.6.0; /* 0.8.x */ contract Token { (
) : (EVM ) : constructor (...) public { /* */ : } function balanceOf(...) { /* ( ) */ : } : } constructor C (/* */ // ) B 2023 — 3 — 2023-10-30 – p.35/66
ERC-20 ERC (Ethereum Request for Comments) 20 https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md (EIP: Ethereum
Improvement Proposal) ← EIP ( ) contract ERC20 { function totalSupply() constant returns (uint totalSupply); function balanceOf(address _owner) constant returns (uint balance); function transfer(address _to, uint _value) returns (bool success); function transferFrom(address _from, address _to, uint _value) returns (bool success); function approve(address _spender, uint _value) returns (bool success); function allowance(address _owner, address _spender) constant returns (uint remaining); event Transfer(address indexed _from, address indexed _to, uint _value); event Approval(address indexed _owner, address indexed _spender, uint _value); } name/ , symbol/ , decimals/ approve allowance ERC-777 ( ) B 2023 — 3 — 2023-10-30 – p.36/66
ERC20 ERC20 ( ) ⇒ ERC20 ( ERC20 ) ERC20
⇒ B 2023 — 3 — 2023-10-30 – p.37/66
(fungible) ERC-20 → ERC-223 (draft) or ERC-777 ( )( )
(non-fungible) ERC-721 ( ) ERC-1155 ( ) ERC-3525 (SLOT ) B 2023 — 3 — 2023-10-30 – p.38/66
Token ( ) string public symbol; string public name; uint256
public decimals; uint256 public totalSupply; mapping(address => uint256) balances; . . . name, symbol decimals : 2 100 1.00 mapping balances B 2023 — 3 — 2023-10-30 – p.39/66
Token ( ) event Transfer(address from, address to, uint256 value);
Token function emit Transfer() ( ) B 2023 — 3 — 2023-10-30 – p.40/66
Token ( ) constructor( string memory _symbol, string memory _name,
uint256 _decimals, uint256 _totalSupply ) public { symbol = _symbol; name = _name; decimals = _decimals; totalSupply = _totalSupply; balances[msg.sender] = _totalSupply; } msg.sender _totalSupply B 2023 — 3 — 2023-10-30 – p.41/66
Token balanceOf() function balanceOf(address _owner) public view returns (uint256) {
return balances[_owner]; } B 2023 — 3 — 2023-10-30 – p.42/66
Token transfer() function transfer(address _to, uint256 _value) public returns (bool)
{ balances[msg.sender] = balances[msg.sender].sub(_value); balances[_to] = balances[_to].add(_value); emit Transfer(msg.sender, _to, _value); return true; } ( ↑ ) OpenZeppelin https://openzeppelin.org B 2023 — 3 — 2023-10-30 – p.43/66
(2) : B 2023 — 3 — 2023-10-30 – p.44/66
GitHub git clone $ git clone https://github.com/ks91/sample-smart-contracts.git sample-smart-contracts contracts, scripts
tests token Token Solidity 0.5 0.6/0.7 (Token ) Solidity B 2023 — 3 — 2023-10-30 – p.45/66
(m2 ) 1 1 B 2023 — 3 — 2023-10-30
– p.46/66
IndivisibleAsset string public _name_; string public _symbol_; uint256 public _quantity_;
address public _owner_; _name_ ( ) _symbol_ _quantity_ (m2 ) _owner_ ‘_’ Solidity . . . B 2023 — 3 — 2023-10-30 – p.47/66
IndivisibleAsset event Transfer(address indexed from, address indexed to); from to
indexed B 2023 — 3 — 2023-10-30 – p.48/66
IndivisibleAsset constructor (string name, string symbol, uint256 quantity) public {
_name_ = name; _symbol_ = symbol; _quantity_ = quantity; _owner_ = msg.sender; } B 2023 — 3 — 2023-10-30 – p.49/66
IndivisibleAsset getOwner() function getOwner() public view returns (address) { return
(_owner_); } B 2023 — 3 — 2023-10-30 – p.50/66
IndivisibleAsset transfer() function transfer(address to) public returns (bool) { require(_owner_
== msg.sender); _owner_ = to; emit Transfer(msg.sender, to); return true; } require (function ) ( ) $ brownie compile B 2023 — 3 — 2023-10-30 – p.51/66
scripts/indivisible asset.py from brownie import * def main(): accounts[0].deploy(IndivisibleAsset, "5322
Endo, Fujisawa", "mˆ2", 300) SFC (300m2 ) ( ) B 2023 — 3 — 2023-10-30 – p.52/66
from brownie import * import pytest def test_owner_and_transfer(IndivisibleAsset): asset =
accounts[0].deploy(IndivisibleAsset, "5322 Endo", "mˆ2", 300) assert asset.getOwner() == accounts[0] asset.transfer(accounts[1], {’from’: accounts[0]}) assert asset.getOwner() == accounts[1] try: asset.transfer(accounts[0], {’from’: accounts[0]}) done = 1 except: done = 0 assert done == 0 accounts[0] accounts[1] B 2023 — 3 — 2023-10-30 – p.53/66
$ pytest tests/test_indivisible_asset.py B 2023 — 3 — 2023-10-30 –
p.54/66
(3) : B 2023 — 3 — 2023-10-30 – p.55/66
transfer settle, retrieve asset, retrieve token 3 B 2023 —
3 — 2023-10-30 – p.56/66
1. ( ) 2. ( ) 3. ( ) B
2023 — 3 — 2023-10-30 – p.57/66
OneTimeEscrow settle() function settle() public returns (bool) { require(_token_.balanceOf(address(this)) >=
_price_); /* this */ require(_asset_.getOwner() == address(this)); _token_.transfer(_seller_ , _price_); _asset_.transfer(_buyer_); emit Settled(); /* */ return true; } settle() transfer ( / ) $ brownie compile B 2023 — 3 — 2023-10-30 – p.58/66
(1) from brownie import * import pytest def test_deploy_and_settle(Token, IndivisibleAsset,
OneTimeEscrow): asset = accounts[0].deploy(IndivisibleAsset, "5322 Endo", "mˆ2", 300) token = accounts[0].deploy(Token, "Test Token", "TEST", 18, "1000 ether") B 2023 — 3 — 2023-10-30 – p.59/66
(2) token.transfer(accounts[1], 300, {’from’: accounts[0]}) escrow = accounts[0].deploy(OneTimeEscrow, token, accounts[1],
asset, accounts[0], 300) accounts[0] accounts[1] 300 300 TX accounts[1] accounts[0] 300 bake Token 300 ETH wei B 2023 — 3 — 2023-10-30 – p.60/66
(3) token.transfer(escrow, 300, {’from’: accounts[1]}) asset.transfer(escrow, {’from’: accounts[0]}) assert token.balanceOf(accounts[0])
== 999999999999999999700 assert token.balanceOf(accounts[1]) == 0 assert token.balanceOf(escrow) == 300 assert asset.getOwner() == escrow accounts[1] ( ) 300 accounts[0] ( ) B 2023 — 3 — 2023-10-30 – p.61/66
(4) escrow.settle({’from’: accounts[0]}) assert token.balanceOf(accounts[0]) == 1000000000000000000000 assert token.balanceOf(accounts[1]) ==
0 assert token.balanceOf(escrow) == 0 assert asset.getOwner() == accounts[1] settle() accounts[0] OK B 2023 — 3 — 2023-10-30 – p.62/66
$ pytest tests/test_one_time_escrow.py : settle() ⇒ Discord B 2023 —
3 — 2023-10-30 – p.63/66
B 2023 — 3 — 2023-10-30 – p.64/66
1. (1) (2) Ethereum 2023 11 4 ( ) 23:59
JST B 2023 — 3 — 2023-10-30 – p.65/66
B 2023 — 3 — 2023-10-30 – p.66/66