使用SDK构建普通交易

本文介绍使用MetaContract SDK构建普通交易（P2PKH）的方法。

使用之前请确保已经完成环境配置和测试币领取，请参考搭建一个MVC项目。

本文基于上述已经配置好的环境和密钥进行操作。

修改源码

将src/index.ts文件替换为以下内容：

import {Mnemonic} from "meta-contract/dist/mvc";
import {promises as fs} from 'fs';
import {API_NET, Wallet} from "meta-contract";

const FILE_PATH = 'mnemonic-seed.txt'
const WALLET_PATH = "m/44'/10001'/0'/0/0"
let seed = '';
const generateMnemonic = async (): Promise<string> => {
    console.log("Generating random mnemonic seed: <%s>, use your own if you already have it", Mnemonic.fromRandom().toString())
    const mnemonic = Mnemonic.fromRandom().toString();
    await fs.writeFile(FILE_PATH, mnemonic, 'utf8');
    return mnemonic;
};

const readMnemonic = async (): Promise<string> => {
    return await fs.readFile(FILE_PATH, 'utf8');
};

// Detect if the mnomonic seed file exists, if not, generate a new one
// Then create a wallet with the seed with path WALLET_PATH
const setupMyWalletAndSend = async (): Promise<void> => {
    try {
        await fs.access(FILE_PATH);
        const mnemonic = await readMnemonic();
        console.log('Mnemonic seed exists: <%s>, will use this one.', mnemonic);
        seed = mnemonic;
    } catch (error) {
        const mnemonic = await generateMnemonic();
        console.log('Mnemonic seed not detected, generating new one. <%s> , please keep it safe for future use.', mnemonic);
        seed = mnemonic;
    }
    console.log('Creating wallet with seed: <%s> and path <%s>', seed, WALLET_PATH);
    let mnemonicParsed = Mnemonic.fromString(seed);
    let privateKey = mnemonicParsed.toHDPrivateKey("", API_NET.TEST).deriveChild(WALLET_PATH);
    let wallet = new Wallet(privateKey.privateKey.toWIF(), API_NET.TEST, 1);
    console.log("Your private key %s", privateKey.privateKey.toWIF());
    console.log("Your address %s", privateKey.privateKey.toAddress(API_NET.TEST).toString());
    console.log("Your balance %s satoshis", await wallet.getBalance());

    // Send 10000 satoshi back to the faucet
    console.log("Sending 10000 satoshis back to the faucet");
    wallet
        .send("mktGt8zJo5qYmXc97SVvCLPvtLExymgBKF", 10000)
        .then((tx) => {
            console.log("Transaction sent, txid %s, rawHex %s", tx.txId, tx.txHex);
        })
        .then(() => wallet.getBalance())
        .then((balance) => {
            console.log("Your balance now is  %s satoshis", balance);
        });
};


setupMyWalletAndSend().catch(console.error);

在初始化钱包的基础上增加了发送Space交易的逻辑。

这段代码的功能介绍：

1. 初始化钱包并打印出地址和余额。
2. 向水龙头发送10000 satoshi。
3. 打印出交易ID和发送交易后的余额。

如果一切正常，你会看到类似以下输出：

Your address mmGruHTY1ivexPzmvjz8AxrhhWWE8BbgN9
Your balance 9928215 satoshis
Sending 10000 satoshis back to the faucet
Transaction sent, txid 602e6d6216dfa059d815c373868f696bf63efee7d798e2f8607213a73148e744, rawHex 0a000000019ed5a08a5dceb21c04faa56529702bd821bb7df9f6ef8a05f4558c34896ca62a010000006a47304402202c202844366d0ea54f0efc297982e19c6e47fd0ac8e94bf9343d304f8bb0da5202203fc50d96855acd27c18c26789362b3a970f7c83dfe2a85e581aaaeb201424648412102b9302409e6a04b5cb8470ef1471e36a894e2676373e51cbcff54e6fa516d12f5ffffffff0210270000000000001976a9143ae0e15c763122be84e4d2d75a9e92b0d8703b2c88ac08569700000000001976a9143f266e0384df8e171b60895832f58aaf4d5b58ab88ac00000000
Your balance now is  9917960 satoshis