スマートコントラクトプログラミング / Smart Contract Programming

2022年10月31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」2022秋で使用したスライドです。

Transcript

1. Service Design, generated by Stable Diffusion B 2022 3 ( ) B 2022 — 3 — 2022-10-31 – p.1/93
2. https://speakerdeck.com/ks91 ( ) ( ) Discord Discord ( / / ) Zoom URL ( ) B 2022 — 3 — 2022-10-31 – p.2/93
3. ( ) 1 10 17 • 2 10 24 • 3 10 31 • 4 11 7 5 11 14 1 6 11 21 2 7 11 28 8 12 5 Discord B 2022 — 3 — 2022-10-31 – p.3/93
4. – : : Ethereum ( ) Ethereum (1)(2)(3) ( ← ) B 2022 — 3 — 2022-10-31 – p.4/93
5. – B 2022 — 3 — 2022-10-31 – p.5/93
6. ެ։୆ா ެ։Ͱͳ͚Ε͹ͳΒͳ͍ ʜ ຊਓ ɾૹۚه࿥ ɾίʔυ ɾσʔλͷมԽ ɾ࣮ߦϩά ݕӾͰ͖Δୈࡾऀ ͜Εɺ ه࿥͍ͨ͠Μ͚ͩͲ ͋ͳͨ͸ ॻ͍ͨΒμϝ ͜ͷ಺༰͸ ॻ͍ͨΒμϝ ॻ͍ͪΌͬͨͷʁ ͜͏ॻ͖׵͑·͠ΐ͏ ॻ͍ͯͳ͍ͷʁ ͜͏ॻ͔Εͨ͜ͱʹ ͠·͠ΐ͏ ॻ͍ͪΌͬͨͷʁ ফ͠·͠ΐ͏ %P4 ߈ܸͱ͔Ͱ ๦֐ͯ͠ࢭΊ·͠ΐ͏ B 2022 — 3 — 2022-10-31 – p.6/93
7. ( ) ( ) ( ) ↓ ( ( )) (BP : Blockchain Property ) BP-1 : ( ) BP-2 : ( ( ) ) BP-3 : ( ) ( ) ( ) B 2022 — 3 — 2022-10-31 – p.7/93
8. ( ) (LIFO : Last In, First Out) ( ) B 2022 — 3 — 2022-10-31 – p.8/93
9. ( ) ( ) ( ) ( ) ( 16 ) SHA (Secure Hash Algorithm) ( ) 1bit B 2022 — 3 — 2022-10-31 – p.9/93
10. ( ) ( ) < , > ( ) ← : < , > : : < , , > : OK ( 1 ) NG ( ) B 2022 — 3 — 2022-10-31 – p.10/93
11. BP-1 ( ), BP-2 ( ) BBc-1 f : → BP-3 ( ) ( ) ( ) ← BP-2 ← BP-3 ( ) (BP-2 ) ( ) ← BP-3 (?) + ← BP-{1,2} B 2022 — 3 — 2022-10-31 – p.11/93
12. [Lamport 1984][Schneider 1990] (1) (2) (3) (4) ( ) ← ↑ B 2022 — 3 — 2022-10-31 – p.12/93
13. TX : transaction ( 4 TX ) SMRP (State Machine Replication Problem) SMRP-1 ( ) SMRP-2 : B 2022 — 3 — 2022-10-31 – p.13/93
14. ( ) ( ) ϒϩοΫ൪߸
    
    O ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ͍ͪ͹Μه࿥ɾॻ͖׵͑ͷίετ͕ߴ͍ྺ࢙ ࠷΋վ͟Μ͠ʹ͍͘ྺ࢙ ͕༗ޮ ͻͱͭखલͷϒϩοΫͷ ʮμΠδΣετʯ σδλϧॺ໊͞Εͨ ʮτϥϯβΫγϣϯ औҾ ʯ ϒϩοΫΛ࡞ΔͨΊʹ͸ɺͦͷʮμΠδΣετʯ͕͋Δ਺ҎԼͱ͍͏৚݅Λຬͨͨ͠Γ 1SPPG
    PG
    8PSL Ծ૝௨՟ͷ࣋ͪ෼ʹԠͨ͡ݖརΛ࢖ͬͨ౤ථͰউͬͨΓ 1SPPG
    PG
    4UBLF ͢Δඞཁ͕͋Δ ίετ͕͔͔Δ ϒϩοΫΛ࡞Δਓ͸ͦͷதʹࣗ෼ʹѼͯͨ Ծ૝௨՟ͰͷใुΛॻ͖ࠐΉ͜ͱ͕Ͱ͖ɺ ͦͷϒϩοΫ͕༗ޮͳྺ࢙ͷதʹ͋Δ৔߹ʹ ݶΓใु΋༗ޮͱͳΔ τϥϯβΫγϣϯͷଘࡏΛ֬ೝ͢Δ ͨΊͷޮ཰తͳํ๏͕ఏڙ͞ΕΔ ਖ਼౰ੑ ଘࡏੑ །Ұੑ Proof of Work ( ) . . . → B 2022 — 3 — 2022-10-31 – p.14/93
15. (BP-3 ) ( : ) (BP-3 ) ( : ) ← NFT BP-{1,2,3} BP-{1, 2} ⇒ B 2022 — 3 — 2022-10-31 – p.15/93
16. (Confidentiality) BP-{1,2,3} ↑ ( = ) (Integrity) BP-3 (Availability) BP-2 B 2022 — 3 — 2022-10-31 – p.16/93
17. 2009 ↑ 13 ( 5 ) B 2022 — 3 — 2022-10-31 – p.17/93
18. ( ) ADR (Active (space) Debris Removal) : https://doi.org/10.1109/TCSS.2018.2890655 (1930 ) ( ) B 2022 — 3 — 2022-10-31 – p.18/93
19. ( ) ( ) ( ) B 2022 — 3 — 2022-10-31 – p.19/93
20. ( ) ( - ) : https://doi.org/10.1016/j.future.2019.05.019 B 2022 — 3 — 2022-10-31 – p.20/93
21. ( ) ( ) ( ) B 2022 — 3 — 2022-10-31 – p.21/93
22. ( ) B 2022 — 3 — 2022-10-31 – p.22/93
23. / ( ) ( ) ( ) ( ) B 2022 — 3 — 2022-10-31 – p.23/93
24. ( ) ( ) ( ) B 2022 — 3 — 2022-10-31 – p.24/93
25. ( ) : https://www.lij.jp/html/jli/jli_2017/ 2017summer_p018.pdf B 2022 — 3 — 2022-10-31 – p.25/93
26. ( ) ( ) B 2022 — 3 — 2022-10-31 – p.26/93
27. B 2022 — 3 — 2022-10-31 – p.27/93
28. with ( ) ( ) : https://doi.org/10.1016/j.icte.2021.08.012 ( ) B 2022 — 3 — 2022-10-31 – p.28/93
29. DNS : https://ieeexplore.ieee.org/document/9686409 ( ) IP AS B 2022 — 3 — 2022-10-31 – p.29/93
30. ( ) ( ) : https://ieeexplore.ieee.org/document/9686409 ( ) : https://doi.org/10.1016/j.icte.2021.08.012 (web ) B 2022 — 3 — 2022-10-31 – p.30/93
31. ( ) ( ) ( ) : https://doi.org/10.1016/j.icte.2021.08.012 ( ) ( ) ( ) : https://ieeexplore.ieee.org/document/9686409 B 2022 — 3 — 2022-10-31 – p.31/93
32. ( ) ( ) : https://ieeexplore.ieee.org/document/9686409 3D : https://arxiv.org/abs/2203.03119 ( ) : HACCP ( ) B 2022 — 3 — 2022-10-31 – p.32/93
33. — τʔΫϯ ୅ସ՟ฎ εϚʔτίϯτϥΫτ ݕূՄೳͳঢ়ଶϚγϯ ϓϩϏφϯε དྷྺূ໌
    ୅ସՄೳ ঈؐෆೳ ୅ସՄೳ ঈؐՄೳ ୅ସෆೳ ঈؐՄೳ ୅ସෆೳ ঈؐෆೳ ূ໌͢Δ ಉఆ͢Δ ࢧ෷͍౳ ࠷ॳͷԠ༻ *%
    Χʔυ౳ ηΩϡϦςΟ τʔΫϯ ূ݊ ౳ ηϯαʔ౳ ෺ྲྀɾ Ҩݴॻ౳ อݥਃ੥౳ ௥੻͢Δ ײ஌͢Δ தԝۜߦ σδλϧ௨՟౳ ҭ੒ήʔϜ౳ ൿີ伴Λ࢖͑Δ͔Βຊਓʁ ෛ࠴  Ξηοτͷ ਺஋දݱΛҠసͰ͖Δʁ ొ࿥͞Εͨίʔυͱ ͦͷ࣮ߦϩάͱ݁Ռͷ ਅਖ਼ੑΛ୲อͰ͖Δʁ ݖҖ͕
    Կ͔ͷ಺༰Λূ໌͢Δʁ ࣋ଓ͢Δଘࡏʹ͍ͭͯ ه࿥ΛΞοϓσʔτՄʁ ओମ͕͍ͳ͘ͳͬͯ΋ աڈͷσʔλ͸༗ޮʁ /'5 Ұൠతͳ ೝࣝ ػೳͷ ෼ੳ݁Ռ B 2022 — 3 — 2022-10-31 – p.33/93
34. Ethereum macOS (Monterey 12.6) + Homebrew Linux (Ubuntu 22.04) (x86/AMD64 and ARM) Windows 10/11 + Windows Subsystem for Linux (Ubuntu ) Ethereum solidity brownie B 2022 — 3 — 2022-10-31 – p.34/93
35. Solidity Ethereum ( ) http://solidity.readthedocs.io/en/latest/installing-solidity.html Linux (on Windows) “sudo apt”, macOS “brew” Linux ARM git clone dependencies solc 0.8.16 (9/6 ) $ solc --version brownie py-solc-x solc (dependencies) ( solc py-solc-x ) B 2022 — 3 — 2022-10-31 – p.35/93
36. 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 2022 — 3 — 2022-10-31 – p.36/93
37. Python3 macOS $ brew install python3 Python 3.8 Homebrew $ brew uninstall --ignore-dependencies python@3.9 $ brew install python@3.8 /usr/local/opt/python@3.8/bin/python3 Linux $ sudo apt update $ sudo apt install python3.8 python3.8-dev python3.8-venv python3.8-tk 16.10 python3(.8) apt (PPA ) python3 python3-dev python3-venv python3-tk B 2022 — 3 — 2022-10-31 – p.37/93
38. macOS : . . . macOS wget brew dyld: Library not loaded: /usr/local/opt/gettext/lib/libintl.8.dylib $ brew uninstall --force gettext $ brew install gettext B 2022 — 3 — 2022-10-31 – p.38/93
39. Python (venv) macOS (Linux python3 ) ‘python3.8’ ‘python3’ $ python3.8 -m venv bbc1env $ source bbc1env/bin/activate (bbc1env) $ pip install -U pip (bbc1env) $ pip install wheel bbc1env ( BBc-1 ) ( ) (bbc1env) $ deactivate B 2022 — 3 — 2022-10-31 – p.39/93
40. Brownie Python Ethereum https://eth-brownie.readthedocs.io Brownie $ pip install eth-brownie version 1.19.1 (9/6 ) B 2022 — 3 — 2022-10-31 – p.40/93
41. $ brownie init ( ERC-20 ) $ brownie bake token $ cd token B 2022 — 3 — 2022-10-31 – p.41/93
42. 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 2022 — 3 — 2022-10-31 – p.42/93
43. Brownie $ brownie console Python >>> len(accounts) 10 >>> accounts[0].balance() 100000000000000000000 >>> quit() B 2022 — 3 — 2022-10-31 – p.43/93
44. Ethereum Görli B 2022 — 3 — 2022-10-31 – p.44/93
45. 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 2022 — 3 — 2022-10-31 – p.45/93
46. G¨ orli ETH brownie console Görli >>> network.disconnect() >>> network.connect(’goerli’) >>> len(accounts) 0 >>> accounts.add() <LocalAccount object ’ 16 ’> >>> accounts[0].private_key 16 >>> quit() Görli Testnet ETH Faucet ETH https://goerlifaucet.com ( ) ( ) https://metamask.io/ B 2022 — 3 — 2022-10-31 – p.46/93
47. 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 2022 — 3 — 2022-10-31 – p.47/93
48. Ethereum B 2022 — 3 — 2022-10-31 – p.48/93
49. Ethereum Vitalik Buterin, “Ethereum White Paper: A NEXT GENERATION SMART CONTRACT & DECENTRALIZED APPLICATION PLATFORM” 12 (= ) = ⇒ → Dapps ( / / ) B 2022 — 3 — 2022-10-31 – p.49/93
50. ( ) B 2022 — 3 — 2022-10-31 – p.50/93
51. . . . B 2022 — 3 — 2022-10-31 – p.51/93
52. vs. B 2022 — 3 — 2022-10-31 – p.52/93
53. = run B 2022 — 3 — 2022-10-31 – p.53/93
54. Ether Ethereum EOA : Externally-Owned Account ( ) Ether EVM EVM B 2022 — 3 — 2022-10-31 – p.54/93
55. EVM : Ethereum Virtual Machine Gas ( EVM = ( burn)) . . . B 2022 — 3 — 2022-10-31 – p.55/93
56. EVM : : ← : Solidity — JavaScript LLL — Lisp Vyper — Python Fe — Vyper Rust ← NEW! Solidity Vyper Python B 2022 — 3 — 2022-10-31 – p.56/93
57. 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 2022 — 3 — 2022-10-31 – p.57/93
58. ( , ) (constructor) (deploy) = ( ) ( ) ETH Trusted Actor Model B 2022 — 3 — 2022-10-31 – p.58/93
59. Ethereum B 2022 — 3 — 2022-10-31 – p.59/93
60. (1) : ERC20 $ brownie bake token B 2022 — 3 — 2022-10-31 – p.60/93
61. Solidity JavaScript ( , ) (constructor) ( ) ( ) Ether Ethereum B 2022 — 3 — 2022-10-31 – p.61/93
62. pragma solidity ˆ0.6.0; /* 0.8.x */ contract Token { ( ) : (EVM ) : constructor (...) public { /* */ : } function balanceOf(...) { /* ( ) */ : } : } constructor C (/* */ // ) B 2022 — 3 — 2022-10-31 – p.62/93
63. ERC20 ERC (Ethereum Request for Comment) 20 https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md 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 2022 — 3 — 2022-10-31 – p.63/93
64. ERC20 ERC20 ( ) ⇒ ERC20 ( ERC20 ) ERC20 ⇒ B 2022 — 3 — 2022-10-31 – p.64/93
65. (fungible) ERC-20 → ERC-223 (draft) or ERC-777 ( )( ) (non-fungible) ERC-721 ( ) ERC-1155 ( ) ERC-3525 (SLOT ) B 2022 — 3 — 2022-10-31 – p.65/93
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 2022 — 3 — 2022-10-31 – p.66/93
67. Token ( ) event Transfer(address from, address to, uint256 value); Token function emit Transfer() ( ) B 2022 — 3 — 2022-10-31 – p.67/93
68. 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 2022 — 3 — 2022-10-31 – p.68/93
69. Token balanceOf() function balanceOf(address _owner) public view returns (uint256) { return balances[_owner]; } B 2022 — 3 — 2022-10-31 – p.69/93
70. 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 2022 — 3 — 2022-10-31 – p.70/93
71. (2) : B 2022 — 3 — 2022-10-31 – p.71/93
72. 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 2022 — 3 — 2022-10-31 – p.72/93
73. (m2 ) 1 1 B 2022 — 3 — 2022-10-31 – p.73/93
74. IndivisibleAsset string public _name_; string public _symbol_; uint256 public _quantity_; address public _owner_; _name_ ( ) _symbol_ _quantity_ (m2 ) _owner_ ‘_’ Solidity . . . B 2022 — 3 — 2022-10-31 – p.74/93
75. IndivisibleAsset event Transfer(address indexed from, address indexed to); from to indexed B 2022 — 3 — 2022-10-31 – p.75/93
76. IndivisibleAsset constructor (string name, string symbol, uint256 quantity) public { _name_ = name; _symbol_ = symbol; _quantity_ = quantity; _owner_ = msg.sender; } B 2022 — 3 — 2022-10-31 – p.76/93
77. IndivisibleAsset getOwner() function getOwner() public view returns (address) { return (_owner_); } B 2022 — 3 — 2022-10-31 – p.77/93
78. 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 2022 — 3 — 2022-10-31 – p.78/93
79. scripts/indivisible asset.py from brownie import * def main(): accounts[0].deploy(IndivisibleAsset, "5322 Endo, Fujisawa", "mˆ2", 300) SFC (300m2 ) ( ) B 2022 — 3 — 2022-10-31 – p.79/93
80. 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 2022 — 3 — 2022-10-31 – p.80/93
81. $ pytest tests/test_indivisible_asset.py B 2022 — 3 — 2022-10-31 – p.81/93
82. (3) : B 2022 — 3 — 2022-10-31 – p.82/93
83. transfer settle, retrieve asset, retrieve token 3 B 2022 — 3 — 2022-10-31 – p.83/93
84. 1. ( ) 2. ( ) 3. ( ) B 2022 — 3 — 2022-10-31 – p.84/93
85. 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 2022 — 3 — 2022-10-31 – p.85/93
86. (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 2022 — 3 — 2022-10-31 – p.86/93
87. (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 2022 — 3 — 2022-10-31 – p.87/93
88. (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 2022 — 3 — 2022-10-31 – p.88/93
89. (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 2022 — 3 — 2022-10-31 – p.89/93
90. $ pytest tests/test_one_time_escrow.py : settle() ⇒ Discord B 2022 — 3 — 2022-10-31 – p.90/93
91. B 2022 — 3 — 2022-10-31 – p.91/93
92. 1. (1) (2) Ethereum 2022 11 5 ( ) 23:59 JST B 2022 — 3 — 2022-10-31 – p.92/93
93. B 2022 — 3 — 2022-10-31 – p.93/93