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

Service Design, generated by Stable Diffusion
B 2022
3
( )
B 2022 — 3 — 2022-10-31 – p.1/93

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https://speakerdeck.com/ks91
( )
( )
Discord
Discord ( / / )
Zoom URL ( )
B 2022 — 3 — 2022-10-31 – p.2/93

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( )
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

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–
:
: Ethereum
( )
Ethereum
(1)(2)(3) ( ← )
B 2022 — 3 — 2022-10-31 – p.4/93

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–
B 2022 — 3 — 2022-10-31 – p.5/93

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ެ։୆ா
ެ։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

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( )
( )
( )
↓
( ( ))
(BP : Blockchain Property )
BP-1 : ( )
BP-2 : ( ( ) )
BP-3 : ( )
( ) ( )
B 2022 — 3 — 2022-10-31 – p.7/93

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( )
(LIFO : Last In, First Out)
( )
B 2022 — 3 — 2022-10-31 – p.8/93

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( ) ( )
( )
(
) ( 16
)
SHA (Secure Hash Algorithm)
( ) 1bit
B 2022 — 3 — 2022-10-31 – p.9/93

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( ) ( )
< , >
( )
←
: < , >
:
: < , , >
: OK ( 1 ) NG ( )
B 2022 — 3 — 2022-10-31 – p.10/93

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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

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[Lamport 1984][Schneider 1990]
(1)
(2)
(3)
(4) ( )
←
↑
B 2022 — 3 — 2022-10-31 – p.12/93

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TX : transaction
( 4 TX )
SMRP (State Machine Replication Problem)
SMRP-1 ( )
SMRP-2
:
B 2022 — 3 — 2022-10-31 – p.13/93

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( ) ( )
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 1SPPGPG8PSL

Ծ૝௨՟ͷ࣋ͪ෼ʹԠͨ͡ݖརΛ࢖ͬͨ౤ථͰউͬͨΓ 1SPPGPG4UBLF
͢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

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(BP-3 ) ( : )
(BP-3 ) ( : )
← NFT
BP-{1,2,3}
BP-{1, 2}
⇒
B 2022 — 3 — 2022-10-31 – p.15/93

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(Conﬁdentiality)
BP-{1,2,3}
↑
( = )
(Integrity)
BP-3
(Availability)
BP-2
B 2022 — 3 — 2022-10-31 – p.16/93

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2009
↑
13
( 5 )
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( )
ADR (Active (space) Debris Removal)
: https://doi.org/10.1109/TCSS.2018.2890655
(1930 )
( )
B 2022 — 3 — 2022-10-31 – p.18/93

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( )
( )
( )
B 2022 — 3 — 2022-10-31 – p.19/93

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( )
( - )
: https://doi.org/10.1016/j.future.2019.05.019
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( )
( )
( )
B 2022 — 3 — 2022-10-31 – p.21/93

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( )
B 2022 — 3 — 2022-10-31 – p.22/93

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/ ( )
( )
( )
( )
B 2022 — 3 — 2022-10-31 – p.23/93

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( )
( )
( )
B 2022 — 3 — 2022-10-31 – p.24/93

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( )
: https://www.lij.jp/html/jli/jli_2017/
2017summer_p018.pdf
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( )
( )
B 2022 — 3 — 2022-10-31 – p.26/93

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B 2022 — 3 — 2022-10-31 – p.27/93

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with
( )
( )
: https://doi.org/10.1016/j.icte.2021.08.012
( )
B 2022 — 3 — 2022-10-31 – p.28/93

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DNS
: https://ieeexplore.ieee.org/document/9686409 ( )
IP
AS
B 2022 — 3 — 2022-10-31 – p.29/93

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( )
( )
:
https://ieeexplore.ieee.org/document/9686409
( )
(web )
B 2022 — 3 — 2022-10-31 – p.30/93

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( )
( )
( )
( )
( )
( )
:
B 2022 — 3 — 2022-10-31 – p.31/93

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( )
( )
:
3D
: https://arxiv.org/abs/2203.03119
( )
:
HACCP ( )
B 2022 — 3 — 2022-10-31 – p.32/93

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—
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

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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
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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 )
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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
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Python3
macOS
$ brew install python3
Python
3.8
Homebrew
$ brew uninstall --ignore-dependencies [email protected]
$ brew install [email protected]
/usr/local/opt/[email protected]/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
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macOS : . . .
macOS wget brew
dyld: Library not loaded: /usr/local/opt/gettext/lib/libintl.8.dylib
$ brew uninstall --force gettext
$ brew install gettext
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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
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Brownie
Python Ethereum
https://eth-brownie.readthedocs.io
Brownie
$ pip install eth-brownie
version 1.19.1 (9/6 )
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$ brownie init
( ERC-20 )
$ brownie bake token
$ cd token
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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
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Brownie
$ brownie console
Python
>>> len(accounts)
10
>>> accounts[0].balance()
100000000000000000000
>>> quit()
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Ethereum Görli
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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
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G¨
orli ETH
brownie console Görli
>>> network.disconnect()
>>> network.connect(’goerli’)
>>> len(accounts)
0
>>> accounts.add()

>>> accounts[0].private_key
16
>>> quit()
Görli Testnet ETH Faucet ETH
https://goerlifaucet.com ( )
( )
https://metamask.io/
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G¨
orli ETH
brownie console Görli ETH
>>> network.disconnect()
>>> network.connect(’goerli’)
>>> len(accounts)
0
>>> accounts.add( 16 )

>>> accounts[0].balace()
ETH
>>> quit()
ETH
>>> accounts[0].transfer(accounts[1], "0.01 ether")
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Ethereum
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Ethereum
Vitalik Buterin, “Ethereum White Paper: A NEXT GENERATION SMART
CONTRACT & DECENTRALIZED APPLICATION PLATFORM”
12
(= )
=
⇒
→
Dapps ( / / )
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( )
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. . .
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vs.
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= run
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Ether
Ethereum
EOA : Externally-Owned Account
( )
Ether EVM
EVM
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EVM : Ethereum Virtual Machine
Gas ( EVM = ( burn))
. . . B 2022 — 3 — 2022-10-31 – p.55/93

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EVM
:
: ←
:
Solidity — JavaScript
LLL — Lisp
Vyper — Python
Fe — Vyper Rust ← NEW!
Solidity
Vyper Python
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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;
}
}
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( , )
(constructor)
(deploy) =
( )
( )
ETH
Trusted Actor Model
B 2022 — 3 — 2022-10-31 – p.58/93

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Ethereum
B 2022 — 3 — 2022-10-31 – p.59/93

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(1) : ERC20
$ brownie bake token
B 2022 — 3 — 2022-10-31 – p.60/93

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Solidity
JavaScript
( , )
(constructor)
( )
( )
Ether
Ethereum
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pragma solidity ˆ0.6.0; /* 0.8.x */
contract Token {
( )
:
(EVM )
:
constructor (...) public { /* */
:
}
function balanceOf(...) { /* ( ) */
:
}
:
}
constructor
C (/* */ // )
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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 ( )
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ERC20
ERC20
( )
⇒ ERC20
( ERC20 )
ERC20
⇒
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(fungible)
ERC-20 → ERC-223 (draft) or ERC-777 ( )( )
(non-fungible)
ERC-721
( )
ERC-1155 ( )
ERC-3525 (SLOT )
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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
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Token ( )
event Transfer(address from, address to, uint256 value);
Token function emit Transfer() ( )
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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
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Token balanceOf()
function balanceOf(address _owner) public view returns (uint256) {
return balances[_owner];
}
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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
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(2) :
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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
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(m2 )
1 1
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IndivisibleAsset
string public _name_;
string public _symbol_;
uint256 public _quantity_;
address public _owner_;
_name_ ( )
_symbol_ _quantity_ (m2 )
_owner_
‘_’ Solidity . . .
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IndivisibleAsset
event Transfer(address indexed from, address indexed to);
from to
indexed
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IndivisibleAsset
constructor (string name, string symbol, uint256 quantity) public {
_name_ = name;
_symbol_ = symbol;
_quantity_ = quantity;
_owner_ = msg.sender;
}
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IndivisibleAsset getOwner()
function getOwner() public view returns (address) {
return (_owner_);
}
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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
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scripts/indivisible asset.py
from brownie import *
def main():
accounts[0].deploy(IndivisibleAsset, "5322 Endo, Fujisawa", "mˆ2", 300)
SFC (300m2 )
( )
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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]})
try:
asset.transfer(accounts[0], {’from’: accounts[0]})
done = 1
except:
done = 0
assert done == 0
accounts[0] accounts[1]
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$ pytest tests/test_indivisible_asset.py
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(3) :
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transfer
settle, retrieve asset, retrieve token 3
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1. ( )
2. ( )
3. ( )
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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
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(1)
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")
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(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
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(3)
token.transfer(escrow, 300, {’from’: accounts[1]})
asset.transfer(escrow, {’from’: accounts[0]})
assert token.balanceOf(accounts[0]) == 999999999999999999700
assert token.balanceOf(escrow) == 300
assert asset.getOwner() == escrow
accounts[1] ( ) 300
accounts[0] ( )
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(4)
escrow.settle({’from’: accounts[0]})
assert token.balanceOf(escrow) == 0
settle()
accounts[0] OK
B 2022 — 3 — 2022-10-31 – p.89/93

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$ pytest tests/test_one_time_escrow.py
:
settle()
⇒ Discord
B 2022 — 3 — 2022-10-31 – p.90/93

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B 2022 — 3 — 2022-10-31 – p.91/93

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1.
(1)
(2) Ethereum
2022 11 5 ( ) 23:59 JST
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B 2022 — 3 — 2022-10-31 – p.93/93

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

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

Kenji Saito
PRO

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

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

Kenji Saito PRO

More Decks by Kenji Saito

Other Decks in Technology

Featured

Transcript

Kenji Saito
PRO