Web3相关概念以及钱包交易流程

NetWork 网络

包含以下信息的一个JSON


{
   "chainId": 1, // 链ID
   "ensAddress": "0x314159265dd8dbb310642f98f50c066173c1259b", // ENS 地址
   "name": "homestead" // network 名称
}

Provider 提供者

提供者是一个连接以太坊网络的抽象，用与查询以太坊网络状态或者发送更改状态的交易。

连接BSC：


const provider = new ethers.providers.JsonRpcProvider('https://bsc-dataseed1.defibit.io/')

Singer 签名器

Wallet 钱包

继承Singer的一个类，主要api：


// 从私钥恢复钱包
const wallte = new Wallet('privateKey');
// 创建一个随机钱包
const wallte = Wallet.createRandom();
// 通过助记词恢复钱包
const wallte  = Wallet.fromMnemonic('mnemonic');

钱包实例主要api：


// 连接一个提供者 并返回一个新的实例
const account = wallet.connect(provider);
// 私钥
wallet.privateKey
// 助记词
wallet.mnemonic
// 地址
wallet.address

// 以下操作需要 connect 一个 provider

// 获取钱包（主币）余额
await wallet.getBalance()
// 获取账号交易数量
await wallet.getTransactionCount()
// 获取测算Gas
await wallet.estimateGas(transation)
// 发送交易到网络
await wallet.sendTransaction(transaction)

Contarct 智能合约

合约是在以太坊区块链上的可执行程序的抽象。合约具有代码 (称为字节代码) 以及分配的长期存储 (storage)。每个已部署的合约都有一个地址, 用它连接到合约, 可以向其发送消息来调用合约方法。

合约可以发出事件, 它可以被应用程序监听（订阅），当合约执行了特定操作时, 应用程序将收到通知。事件是无法在合约内读取的。

在合约上可以调用两种类型的方法：

视图方法 : 不能添加、移除或更改存储中的任何数据，也不能记录任何事件，并且只能调用其他合约上**视图方法**。这些方法是免费的（不需要以太）调用。结果也可以返回给调用者。
非视图方法: 需要支付费用（用Ether），但可以执行任何所需的状态更改操作，记录事件，发送ether并在其他合约上调用非视图方法。这些方法**不能**将其结果返回给调用者。这些方法必须由交易触发，由外部拥有的账户（EOA）直接或间接发送（如从另一个合约调用），并且只有在交易被打包（挖矿）后才会产生效果。因此，这些操作所需的持续时间可能变化很大，并且取决于交易Gas价格、网络拥塞和矿工优先选择方法。

合约 API 提供了简单的方法来连接到一个合约并调用它的方法，它作为 JavaScript 对象上的函数，处理所有的二进制协议转换，内部名称修改和主题构造。这使得合约对象可以像任何标准的JavaScript对象一样使用，而不必担心以太坊虚拟机或区块链的低级细节。

合约Contract对象是一个元类，它是一个在运行时定义类的类。可以提供合约定义（称为应用程序二进制接口或ABI）以及可用的方法和事件可以动态添加到对象中。

ABI 应用二进制接口 application binary interface

对合约中的功能和事件的接口进行描述

连接合约


const contract = new ethers.Contract(
	contarctAddress,
	abi,
	provider
	);

Event Emitter 事件触发器


// 注册合约事件回调
contract.on('eventName',()=>{
....
})
// 注册一次性合约事件回调
contract.once('eventName',()=>{
....
})
// 触发合约事件
contract.emit('eventName',()=>{
....
})

查询对应token信息余额


// 通过私钥连接钱包
const wallet = new ethers.Wallet('0x9b06f68b238c23c125481a3f61076e9e41812dba92013bc3c531b7950e77605d');
// 钱包地址
const address = wallet.address;

// 连接主网
const provider = new ethers.providers.JsonRpcProvider('https://data-seed-prebsc-1-s3.binance.org:8545');
wallet.connect(provider)

// 币种合约地址
const contarctAddress = '0x7ef95a0FEE0Dd31b22626fA2e10Ee6A223F8a684'; // USDT
// 币种合约abi 可通过bsc查询
const abi =  [{"inputs":[],"payable":false,"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"owner","type":"address"},{"indexed":true,"internalType":"address","name":"spender","type":"address"},{"indexed":false,"internalType":"uint256","name":"value","type":"uint256"}],"name":"Approval","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"previousOwner","type":"address"},{"indexed":true,"internalType":"address","name":"newOwner","type":"address"}],"name":"OwnershipTransferred","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"from","type":"address"},{"indexed":true,"internalType":"address","name":"to","type":"address"},{"indexed":false,"internalType":"uint256","name":"value","type":"uint256"}],"name":"Transfer","type":"event"},{"constant":true,"inputs":[],"name":"_decimals","outputs":[{"internalType":"uint8","name":"","type":"uint8"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"_name","outputs":[{"internalType":"string","name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"_symbol","outputs":[{"internalType":"string","name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[{"internalType":"address","name":"owner","type":"address"},{"internalType":"address","name":"spender","type":"address"}],"name":"allowance","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"internalType":"address","name":"spender","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"approve","outputs":[{"internalType":"bool","name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[{"internalType":"address","name":"account","type":"address"}],"name":"balanceOf","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"burn","outputs":[{"internalType":"bool","name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"decimals","outputs":[{"internalType":"uint8","name":"","type":"uint8"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"internalType":"address","name":"spender","type":"address"},{"internalType":"uint256","name":"subtractedValue","type":"uint256"}],"name":"decreaseAllowance","outputs":[{"internalType":"bool","name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"getOwner","outputs":[{"internalType":"address","name":"","type":"address"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"internalType":"address","name":"spender","type":"address"},{"internalType":"uint256","name":"addedValue","type":"uint256"}],"name":"increaseAllowance","outputs":[{"internalType":"bool","name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":false,"inputs":[{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"mint","outputs":[{"internalType":"bool","name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"name","outputs":[{"internalType":"string","name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[],"name":"renounceOwnership","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"symbol","outputs":[{"internalType":"string","name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"totalSupply","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"internalType":"address","name":"recipient","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"transfer","outputs":[{"internalType":"bool","name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":false,"inputs":[{"internalType":"address","name":"sender","type":"address"},{"internalType":"address","name":"recipient","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"transferFrom","outputs":[{"internalType":"bool","name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":false,"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"}]
// 连接合约   
const contract = new ethers.Contract(
	contarctAddress,
	abi,
	provider
	);

// 查询余额
contract.balanceOf(address).then((res:any)=>{
	console.log(res)
	})

/**
合约一般包含以下方法
name：返回 token 名称
symbol：返回 token 的符号，比如EOS
totalSupply：返回 token 的总供应量
balanceOf：返回账户的金额
transfer：对 token 进行交易
**/

GAS 手续费

gasLimit * gasPrice ,gasLimit 的最小值为 21000，但用户可以设置，gasPrice 和当前区块相关，如果 gas 费设置过低，交易有可能失败，手续费不会被退还。如果 gas 费设置过高，没有使用的 gas 会被返还。

Transaction 交易

通过wallet.sendTransaction() 发起交易。

交易请求


{
    // Required unless deploying a contract (in which case omit)
    to: addressOrName,  // the target address or ENS name

    // These are optional/meaningless for call and estimateGas
    nonce: 0,           // the transaction nonce
    gasLimit: 0,        // the maximum gas this transaction may spend
    gasPrice: 0,        // the price (in wei) per unit of gas

    // These are always optional (but for call, data is usually specified)
    data: "0x",         // extra data for the transaction, or input for call
    value: 0,           // the amount (in wei) this transaction is sending
    chainId: 3          // the network ID; usually added by a signer
}

交易回复


{
    // Only available for mined transactions
    blockHash: "0x7f20ef60e9f91896b7ebb0962a18b8defb5e9074e62e1b6cde992648fe78794b",
    blockNumber: 3346463,
    timestamp: 1489440489,

    // Exactly one of these will be present (send vs. deploy contract)
    // They will always be a properly formatted checksum address
    creates: null,
    to: "0xc149Be1bcDFa69a94384b46A1F91350E5f81c1AB",

    // The transaction hash
    hash: "0xf517872f3c466c2e1520e35ad943d833fdca5a6739cfea9e686c4c1b3ab1022e",

    // See above "Transaction Requests" for details
    data: "0x",
    from: "0xEA674fdDe714fd979de3EdF0F56AA9716B898ec8",
    gasLimit: utils.bigNumberify("90000"),
    gasPrice: utils.bigNumberify("21488430592"),
    nonce: 0,
    value: utils.parseEther(1.0017071732629267),

    // The chain ID; 0 indicates replay-attack vulnerable
    // (eg. 1 = Homestead mainnet, 3 = Ropsten testnet)
    chainId: 1,

    // The signature of the transaction (TestRPC may fail to include these)
    r: "0x5b13ef45ce3faf69d1f40f9d15b0070cc9e2c92f3df79ad46d5b3226d7f3d1e8",
    s: "0x535236e497c59e3fba93b78e124305c7c9b20db0f8531b015066725e4bb31de6",
    v: 37,

    // The raw transaction (TestRPC may be missing this)
    raw: "0xf87083154262850500cf6e0083015f9094c149be1bcdfa69a94384b46a1f913" +
           "50e5f81c1ab880de6c75de74c236c8025a05b13ef45ce3faf69d1f40f9d15b0" +
           "070cc9e2c92f3df79ad46d5b3226d7f3d1e8a0535236e497c59e3fba93b78e1" +
           "24305c7c9b20db0f8531b015066725e4bb31de6"
}

交易收据


{
    transactionHash: "0x7dec07531aae8178e9d0b0abbd317ac3bb6e8e0fd37c2733b4e0d382ba34c5d2",

    // The block this transaction was mined into
    blockHash: "0xca1d4d9c4ac0b903a64cf3ae3be55cc31f25f81bf29933dd23c13e51c3711840",
    blockNumber: 3346629,

    // The index into this block of the transaction
    transactionIndex: 1,

    // The address of the contract (if one was created)
    contractAddress: null,

    // Gas
    cumulativeGasUsed: utils.bigNumberify("42000"),
    gasUsed: utils.bigNumberify("21000"),

    // Logs (an Array of Logs)
    log: [ ],
    logsBloom: "0x00" ... [ 256 bytes of 0 ] ... "00",

    // Post-Byzantium hard-fork
    byzantium: false

    ////////////
    // Pre-byzantium blocks will have a state root:
    root: "0x8a27e1f7d3e92ae1a01db5cce3e4718e04954a34e9b17c1942011a5f3a942bf4",

    ////////////
    // Post-byzantium blocks will have a status (0 indicated failure during execution)
    // status: 1
}

通过钱包进行转帐

连接 network


const provider = new ethers.providers.JsonRpcProvider('https://bsc-dataseed1.defibit.io/');

创建 wallet


const wallet = new ethers.Wallet('privatekey');

将 wallet 连接到 network ，获得 signer


const account = wallet.connect(provider);

查询 gasPrice


const gas_price = provider.getGasPrice();

构造交易参数


const tx = {
  from: send_account,
  to: to_address,
  value: ethers.utils.parseEther(send_token_amount),
  nonce: window.ethersProvider.getTransactionCount(send_account, "latest"),
  gasLimit: ethers.utils.hexlify(gas_limit), // 100000
  gasPrice: gas_price,
}

使用 signer 进行转账


account.sendTransaction(tx).then((transaction) => {
  console.dir(transaction)
  alert("Send finished!")
})

使用合约进行转账

连接 network


const provider = new ethers.providers.JsonRpcProvider('https://bsc-dataseed1.defibit.io/');

创建 wallet


const wallet = new ethers.Wallet('privatekey');

将 wallet 连接到 network ，获得 signer


const account = wallet.connect(provider);

连接 contact


let contract = new ethers.Contract('contractAddress' , 'abi' , account);

转账


contract.transfer(to_address, ethers.utils.parseEther(send_token_amount));