简单介绍
官网传送门 Truffle是针对基于以太坊的Solidity语言的一套开发框架。本身基于Javascript，使用以太坊虚拟机（EVM）的世界一流的开发环境，用于区块链的测试框架和资产管道，旨在简化开发人员的生活。
安装truffle
安装前提：
预装nodejs
1.全局安装
npm install -g truffle
建立软链接
ln -s /opt/node-v10.16.0-linux-x64/bin/truffle /usr/local/bin/truffle
2.单个项目安装
npm install truffle
3.查看版本号
truffle version
4.安装成功
构建应用
快速开始 https://www.trufflesuite.com/docs/truffle/quickstart
创建项目
mkdir simple-dapp
初始化项目
truffle init
Note: You can use the truffle unbox <box-name> command to download any of the other Truffle Boxes.
Note: To create a bare Truffle project with no smart contracts included, use truffle init.
本次采用基于webpack的box来构建
truffle unbox webpack
项目目录结构：
- app/:Diretory for app
-
contracts/: Directory for Solidity contracts -
migrations/: Directory for scriptable deployment files -
test/: Directory for test files for testing your application and contracts -
truffle-config.js: Truffle configuration file
创建合约：位于contracts文件夹下
pragma solidity >=0.4.21 <0.7.0;
contract Voting {
//候选人得票数目
mapping (bytes32=>uint8) public votesReceived;
//候选人
bytes32[] public candidateList;
//构造器
constructor(bytes32[] memory candidateNames) public {
candidateList = candidateNames;
}
//查询投票数目
function totalVotesFor(bytes32 candidate) view public returns (uint8){
//非空校验
require(validCandidate(candidate));
return votesReceived[candidate];
}
//投票
function VotingTo(bytes32 candidate) public {
//非空校验
require(validCandidate(candidate));
//add
votesReceived[candidate]+=1;
}
//校验
function validCandidate(bytes32 candidate) view public returns (bool){
for(uint i = 0;i<candidateList.length;i++){
if(candidateList[i]==candidate){
return true;
}
}
return false;
}
}
View Code
创建迁移文件：位于migrations文件夹下
const voting = artifacts.require('../contracts/Voting.sol')
module.exports = function (deployer) {
deployer.deploy(voting,['Mikey','Leo','Don'].map(x=>web3.utils.asciiToHex(x)),{gas:2900000});
}
3_deploy_voting.js
编译智能合约
truffle compile
生成json文件
启动truffle的开发者模式
truffle develop
部署智能合约
migrate
Starting migrations... ====================== > Network name: 'develop' > Network id: 5777 > Block gas limit: 0x6691b7 1_initial_migration.js ====================== Deploying 'Migrations' ---------------------- > transaction hash: 0x5d23f5f2452d41a20ee56b238efb21c9c81cb04e0105c874e5a26528538476e5 > Blocks: 0 Seconds: 0 > contract address: 0xD97313Cb13D2d39Bd8CD2CB6f3606aaCB89fa1Ad > block number: 13 > block timestamp: 1578995366 > account: 0x9c29d178Ba516574E372e3cf5Eda833359F4114F > balance: 99.96269208 > gas used: 263741 > gas price: 20 gwei > value sent: 0 ETH > total cost: 0.00527482 ETH > Saving migration to chain. > Saving artifacts ------------------------------------- > Total cost: 0.00527482 ETH 2_deploy_contracts.js ===================== Deploying 'ConvertLib' ---------------------- > transaction hash: 0x71bc728418b983c24aa541ffebffc8b2eafa53f1f5754e8a800a8f5688947069 > Blocks: 0 Seconds: 0 > contract address: 0x7caC31cFfE12a8A4D7F7bD83a97e3AF0E99206CE > block number: 15 > block timestamp: 1578995366 > account: 0x9c29d178Ba516574E372e3cf5Eda833359F4114F > balance: 99.95973214 > gas used: 105974 > gas price: 20 gwei > value sent: 0 ETH > total cost: 0.00211948 ETH Linking ------- * Contract: MetaCoin <--> Library: ConvertLib (at address: 0x7caC31cFfE12a8A4D7F7bD83a97e3AF0E99206CE) Deploying 'MetaCoin' -------------------- > transaction hash: 0x36bef9d0355bfcf5fd0fad5fd69574b9be37117b92883f03d1e76877cc07e045 > Blocks: 0 Seconds: 0 > contract address: 0xaAd2C9659fec947A764b244E37A281d219fb0a21 > block number: 16 > block timestamp: 1578995366 > account: 0x9c29d178Ba516574E372e3cf5Eda833359F4114F > balance: 99.9529182 > gas used: 340697 > gas price: 20 gwei > value sent: 0 ETH > total cost: 0.00681394 ETH > Saving migration to chain. > Saving artifacts ------------------------------------- > Total cost: 0.00893342 ETH 3_initial_voting.js =================== Deploying 'Voting' ------------------ > transaction hash: 0x0a5c69ce8595788ef70513f2533af7f7a2c230525d50d68abaf30e49fed2c2ff > Blocks: 0 Seconds: 0 > contract address: 0xdafBED4742Ff4b2bC17f0908D2E97DfA644B5417 > block number: 18 > block timestamp: 1578995366 > account: 0x9c29d178Ba516574E372e3cf5Eda833359F4114F > balance: 99.94517058 > gas used: 360358 > gas price: 20 gwei > value sent: 0 ETH > total cost: 0.00720716 ETH > Saving migration to chain. > Saving artifacts ------------------------------------- > Total cost: 0.00720716 ETH Summary ======= > Total deployments: 4 > Final cost: 0.0214154 ETH truffle(develop)>输出结果
部署成功
构建DApp
import Web3 from "web3";
import metaCoinArtifact from "../../build/contracts/MetaCoin.json";
const App = {
web3: null,
account: null,
meta: null,
start: async function() {
const { web3 } = this;
try {
// get contract instance
const networkId = await web3.eth.net.getId();
const deployedNetwork = metaCoinArtifact.networks[networkId];
this.meta = new web3.eth.Contract(
metaCoinArtifact.abi,
deployedNetwork.address,
);
// get accounts
const accounts = await web3.eth.getAccounts();
this.account = accounts[0];
this.refreshBalance();
} catch (error) {
console.error("Could not connect to contract or chain.");
}
},
refreshBalance: async function() {
const { getBalance } = this.meta.methods;
const balance = await getBalance(this.account).call();
const balanceElement = document.getElementsByClassName("balance")[0];
balanceElement.innerHTML = balance;
},
sendCoin: async function() {
const amount = parseInt(document.getElementById("amount").value);
const receiver = document.getElementById("receiver").value;
this.setStatus("Initiating transaction... (please wait)");
const { sendCoin } = this.meta.methods;
await sendCoin(receiver, amount).send({ from: this.account });
this.setStatus("Transaction complete!");
this.refreshBalance();
},
setStatus: function(message) {
const status = document.getElementById("status");
status.innerHTML = message;
},
};
window.App = App;
window.addEventListener("load", function() {
if (window.ethereum) {
// use MetaMask's provider
App.web3 = new Web3(window.ethereum);
window.ethereum.enable(); // get permission to access accounts
} else {
console.warn(
"No web3 detected. Falling back to http://127.0.0.1:8545. You should remove this fallback when you deploy live",
);
// fallback - use your fallback strategy (local node / hosted node + in-dapp id mgmt / fail)
App.web3 = new Web3(
new Web3.providers.HttpProvider("http://127.0.0.1:8545"),
);
}
App.start();
});
index.js
相关资料
官网文档：https://www.trufflesuite.com/docs/truffle/overview
参考博文：https://truffle.tryblockchain.org/