ソフトウェアエンジニアの技術ブログ：Software engineer tech blog

Ethereum uses ECDSA to generate public-private key pairs as Bitcoin does.
Ethereum address is generated by hashing public key with keccak256, slicing last 20 bytes, and adding “0x” at the top.

privateKey -> derive with ECDSA -> publicKey -> hash -> Ethereum address

const Web3 = require("web3");

const mnemonic = "*";

const HDWalletProvider = require('truffle-hdwallet-provider');
let provider = new HDWalletProvider(mnemonic, 'https://ropsten.infura.io/v3/*', 0, 1);

let web3 = new Web3(provider);

let account = web3.eth.accounts.create();

console.log("address:" + account.address);
console.log("privateKey:" + account.privateKey);

$ node address.js
address:0xefC5B5d9A4BDA3bE4f4da8e7AaFe25F08C5EAce7
privateKey:********
$ node address.js
address:0xB19C2356a88F5437e253d404DA642EC914dCC794
privateKey:********

ニーモニック(mnemonic)はあるだけで口座管理ができる
キーストアはパスワードがないと何も出来ない
MetaMaskのウォレットではmnemonicから秘密鍵を作る仕組みがある

### mnemonic
12ワードは128bitのエントロピーから生成される(randomな値)
エントロピーからチェックサムを生成し足し合わせバイト列に変換し11bit(最大2048)ごとに分割
分割した値をindex値としてワードリストの索引
PBKDF2-SHA512から生成 2048回ストレッチ

なるほど、中々凄いことになってるわ

sample_greeting.sol

contract SampleGreeting {
	string greeting = 'Hello World';

	function getGreet() public view returns (string memory){
		return greeting;
	}
}

$ sudo snap install solc
$ solc –bin –abi sample_greeting.sol
sample_greeting.sol:1:1: Warning: Source file does not specify required compiler version! Consider adding “pragma solidity ^0.5.16;”
contract SampleGreeting {
^ (Relevant source part starts here and spans across multiple lines).

======= sample_greeting.sol:SampleGreeting =======
Binary:
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
Contract JSON ABI
[{“constant”:true,”inputs”:[],”name”:”getGreet”,”outputs”:[{“internalType”:”string”,”name”:””,”type”:”string”}],”payable”:false,”stateMutability”:”view”,”type”:”function”}]

const Web3 = require('web3');

const mnemonic = "*";

const HDWalletProvider = require('truffle-hdwallet-provider');
let provider = new HDWalletProvider(mnemonic, 'https://ropsten.infura.io/v3/*', 0, 1);

let web3 = new Web3(provider);

let bin = '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';
let abi = [{"constant":true,"inputs":[],"name":"getGreet","outputs":[{"internalType":"string","name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"}];
let data = {
	'data': bin
}

let contract = new web3.eth.Contract(abi, null, data);
console.log('contract:', contract);

$ node sample.js
///
_jsonInterface:
[ { constant: true,
inputs: [],
name: ‘getGreet’,
outputs: [Array],
payable: false,
stateMutability: ‘view’,
type: ‘function’,
signature: ‘*’ } ] }

signatureの値をメモしておく

web3.eth.getGasPrice().
	then((averageGasPrice) => {
		console.log("gasPrice: " + averageGasPrice);
	}).catch(console.error);

web3.eth.getAccounts((error, result) => {
	console.log('result: ', result);

	web3.eth.getTransactionCount(result[0], (error, response)=>{
		console.log('nonce:', response);
	})
})

contract.deploy().estimateGas().
	then((estimatedGas) => {
		console.log("gas: " + estimatedGas);
	}).catch(console.error);

$ node sample.js
result: [ ‘*’ ]
gasPrice: 1500000013
gas: 164431
nonce: 3

let sender_address = "*";
let nonce = '3';
let chainId = '3';
let gas = 164431;
let gasPrice = '1500000013'

let tx = {
  'from': sender_address,
  'nonce': nonce,
  'chainId': chainId,
  'gas': gas,
  'gasPrice': gasPrice,
  'data': bin,
}

const PRIVATE_KEY = "*";

web3.eth.accounts.signTransaction(tx, PRIVATE_KEY, (error, response)=>{
    console.log(response);
});

{ messageHash:
‘0x71d7*’,
v: ‘0x2a’,
r:
‘0xd04f9c44192de22c1088feccc*’,
s:
‘0x593a5ec5a50d1d5bed367*’,
rawTransaction:
‘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*’,
transactionHash:
‘0x55a06ab424128b04b9002fe7de1a17e8981d94728bac06dd55993cfdba1b860d’ }

デプロイ

let raw = '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*';

web3.eth.sendSignedTransaction(raw).on('receipt', console.log);

$ node sample.js
{ blockHash:
‘0x8414d2fac3b36315828b7d330287a181e3b58ac29ee5d1325fb27b6d92dc03d1’,
blockNumber: 11682111,
contractAddress: ‘0x31695391C6C0f3A3F2EDe7cDb9B13Da277A8e2Eb’,
cumulativeGasUsed: 1680291,
effectiveGasPrice: ‘0x59682f0d’,
from: ‘0x71c9f1d5be00173ae7b774bdbe2112cdd03c5c92’,
gasUsed: 164431,
logs: [],
logsBloom:
‘0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000’,
status: true,
to: null,
transactionHash:
‘0x55a06ab424128b04b9002fe7de1a17e8981d94728bac06dd55993cfdba1b860d’,
transactionIndex: 13,
type: ‘0x0’ }

web3.eth.getAccounts((error, result)=> {
	let sender_address = result[0]
	let call_data = {
		'from': sender_address,
		'to': recipient_address,
		'data': signature
	}

	web3.eth.call(call_data, (error, response) => {
		console.log('response: ', response);
		provider.engine.stop();
	})
})

$ node sample.js
response: 0x0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000b48656c6c6f20576f726c64000000000000000000000000000000000000000000

おおおお なるほど
solidityでcompileしたデータを、from, nonce, chainId, gas, gasPriceなどと一緒にトランザクションにして秘密鍵で署名してデプロイしてるのね。

一連の流れはわかった!

$ mkdir rinkeby
$ cd rinkeby
$ npm init

{
  "name": "inbox",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC"
}

solidityのcompilerをinstall
$ npm install –save solc

mocha(テストフレーム)をinstall
$ npm install –save mocha ganache-cli web3@1.0.0-beta.26

truffle-hdwallet-providerをインストール
$ npm install –save truffle-hdwallet-provider@0.0.3

const path = require('path');
const fs = require('fs');
const solc = require('solc');

const inboxPath = path.resolve(__dirname, 'contracts', 'Inbox.sol');
const source = fs.readFileSync(inboxPath, 'utf8');

moudle.exports = solc.compile(source,1).contracts[':Inbox'];

Inbox.sol

pragma solidity ^0.8.11;

contract Inbox {
	string public message;

	function Inbox(string initialMessage) public {
		message = initialMessage;
	}

	function setMessage(string newMessage) public {
		message = newMessage;
	}
}

deploy.js

const HDWalletProvider = require('truffle-hdwallet-provider');
const Web3 = require('web3');
const { interface, bytecode } = require('./compile');

const provider = new HDWalletProvider (
	'harmonic',
	'https://ropsten.infura.io/v3/*'
);

const web3 = new Web3(provider);

const deploy = async () => {

	const accounts = await web3.eth.getAccounts();

	console.log('Attempting to deploy from account', accounts[0]);

	const result = await new web3.eth.Contract(JSON.parse(interface))
		.deploy({data: bytecode, arguments:['Hi there!']})
		.send({gas:'1000000', from: accounts:[0]});

	console.log('Contract deploy to', result.options.address);
}

$ node deploy.js
Attempting to deploy from account *
(node:408216) UnhandledPromiseRejectionWarning: Error: intrinsic gas too low

うーむ、gasの設定の方法がよくわかん
gasの概念の理解が先か…

Rapstonだと、送金処理ができなかったので、private netに接続します。
勝った時のみ、Etherの送金処理を実行します。

<div class="container">
	<h1>Ethereum</h1>
	<div id="balanceArea"></div>
	<br><br>
	<h1>じゃんけん</h1>
	<button onclick="R_Click(0)">グー</button>
	<button onclick="R_Click(1)">チョキ</button>
	<button onclick="R_Click(2)">パー</button>
	<br><br>
	<div id="area1"></div>
	<div id="area2"></div>
	</div>
	<script>
		let balanceArea = document.getElementById('balanceArea');
		const web3 = new Web3();
		const userWallet = "";
		const adminWallet = "";
		web3.setProvider(new web3.providers.HttpProvider('http://192.168.33.10:8545'));

		function R_Click(p_janken_r){
			let janken = ["グー","チョキ","パー"];
			let janken_r = Math.floor(Math.random()*3);

			let p_janken = ["グー","チョキ","パー"];

　　　　　　　if (janken_r === p_janken_r) {
				Result_end = "あいこです";
			} else if(p_janken_r === 0 && janken_r === 1) {
				Result_end = "あなたの【勝ち】"; 
				win();
			} else if(p_janken_r === 1 && janken_r === 2) {
				Result_end = "あなたの【勝ち】"; 
				win();
			} else if(p_janken_r === 2 && janken_r === 0) {
				Result_end = "あなたの【勝ち】";
				win();
			} else {
				Result_end = "あなたの【負け】";
				lose();
			}
			document.getElementById("area1").innerHTML = p_janken[p_janken_r] +"を選択しました。ジャンケンの結果は・・・？<br><br>";
            document.getElementById("area2").innerHTML = "相手は" + janken[janken_r] + "! "+ Result_end;
		}
		
		main();

		async function main(){
			web3.eth.getBalance(adminWallet).then((result, error) => {
				const balance = web3.utils.fromWei(result, 'ether');
				console.log(balance);
				balanceArea.innerHTML = balance + " eth";
			});
		}

		async function win(){
			console.log("win");
			var balance = web3.eth.sendTransaction({from: userWallet, to:adminWallet, value:200});
			console.log(balance);
			main();
		}

		async function lose(){
			main();
		}
		
	</script>

トランザクションが生成されてブロックで承認されないと送金処理は実行されないので、じゃんけんに勝っても直ぐにはbalanceに反映されない。

なるほど、理解が深まった。

infura.ioで新規にprojectを作成する
https://infura.io/dashboard

projectのendpointをメモする

メモしたendpointに接続する

<script src="https://cdnjs.cloudflare.com/ajax/libs/web3/1.7.0-rc.0/web3.min.js"></script>
	<script>
		var web3 = new Web3();
		web3.setProvider(new web3.providers.HttpProvider('https://mainnet.infura.io/v3/*'));
		var _balance = web3.eth.getBalance("${wallet address}");
		console.log(_balance)
	</script>

なるほどー　殆ど謎が解けた

CryptoKitties
https://www.cryptokitties.co/

ソースコード
-> contractが公開されている
https://etherscan.io/address/0x06012c8cf97bead5deae237070f9587f8e7a266d#code

contractを継承

contract KittyAccessControl
contract KittyBase is KittyAccessControl
contract KittyOwnership is KittyBase, ERC721
contract KittyBreeding is KittyOwnership
contract KittyAuction is KittyBreeding
contract KittyMinting is KittyAuction
contract KittyCore is KittyMinting

function setGeneScienceAddress(address _address) external onlyCEO {
        GeneScienceInterface candidateContract = GeneScienceInterface(_address);

        // NOTE: verify that a contract is what we expect - https://github.com/Lunyr/crowdsale-contracts/blob/cfadd15986c30521d8ba7d5b6f57b4fefcc7ac38/contracts/LunyrToken.sol#L117
        require(candidateContract.isGeneScience());

        // Set the new contract address
        geneScience = candidateContract;
    }

function giveBirth(uint256 _matronId)
        external
        whenNotPaused
        returns(uint256)
    {
        // Grab a reference to the matron in storage.
        Kitty storage matron = kitties[_matronId];

        // Check that the matron is a valid cat.
        require(matron.birthTime != 0);

        // Check that the matron is pregnant, and that its time has come!
        require(_isReadyToGiveBirth(matron));

        // Grab a reference to the sire in storage.
        uint256 sireId = matron.siringWithId;
        Kitty storage sire = kitties[sireId];

        // Determine the higher generation number of the two parents
        uint16 parentGen = matron.generation;
        if (sire.generation > matron.generation) {
            parentGen = sire.generation;
        }

        // Call the sooper-sekret gene mixing operation.
        uint256 childGenes = geneScience.mixGenes(matron.genes, sire.genes, matron.cooldownEndBlock - 1);

        // Make the new kitten!
        address owner = kittyIndexToOwner[_matronId];
        uint256 kittenId = _createKitty(_matronId, matron.siringWithId, parentGen + 1, childGenes, owner);

        // Clear the reference to sire from the matron (REQUIRED! Having siringWithId
        // set is what marks a matron as being pregnant.)
        delete matron.siringWithId;

        // Every time a kitty gives birth counter is decremented.
        pregnantKitties--;

        // Send the balance fee to the person who made birth happen.
        msg.sender.send(autoBirthFee);

        // return the new kitten's ID
        return kittenId;
    }

uint256 childGenes = geneScience.mixGenes(matron.genes, sire.genes, matron.cooldownEndBlock – 1); の mixGenesで配合している

1. ブラウザでRemixのサイトを開く
https://remix.ethereum.org/#optimize=false&runs=200&evmVersion=null&version=soljson-v0.8.7+commit.e28d00a7.js

2. 左メニューでイーサのマークをクリックし、Injected web3を選択する

3. contractを作成し、compilerを0.4.16に合わせてコンパイル

4. 1億tmcnをdeploy
100000000, “Timecoin”, “TMCN”

5. metamaskに通知が来るのでconfirm

6. deployされる

7. Etherscanでtransactionが確認できる

8. Metamaskのtoken importでcontractのhashを入力し、トークンをインポートする

9. MyEtherWalletにログイン
timecoin, tmcnが入っているのがわかる

10. tachyon walletをインストール

11. QRコードでコントラクトをQRコード化する
QRコード作成サイト
https://www.cman.jp/QRcode/qr_make/
{ERC20:0xeE19196D02D69012c4e7Ce962B528360681F8E36}

12. tachyon walletで networkをRopstenにして、新しい通貨を追加

13. MetaMaskからtachyon walletのアドレスに向けて送信

14. tachyon walletで受け取り

おおおおおおおおおおおおおおおおおお
大分概念を理解した^^
Ethを動かした方が早いですね