以太坊 DAPP 到 HPB 区块链的平滑迁移案例
1 概述
1.1 前言
本文档主要从技术角度对HPB区块链去中心化应用（以下简称“DAPP”）项目常用的演示案例，包括Web3js，JAVA
文档阅读人员：社区开发人员、测试人员、运维人员。
1.2 项目背景
为全面推进DAPP系统建设，落实软件产品线和领域工程的具体要求，形成自主产权基础框架和领域构件库，设立了DAPP项目。
2 把基于以太坊的ERC20的HPB代币平滑迁移到HPB区块链上
2.1 迁移流程如下
2.2 在太坊浏览器查询HPB ERC20 Token
进入以太坊浏览器查询HPB ERC20 Token
在搜索框输入HPB，选择HPBCoin
2.3 复制HPB ERC20 Token源代码到remix
点击HPBERC20的智能合约地址
然后点击Code查看HPB ERC20的源代码
点击Copy复制源代码
打开solidity智能合约在线编译器
粘贴代码到编辑器中，选择编译器编译版本为v0.4.11
2.4 重新编译HPB ERC20 Token源代码
点击查看详情
2.5 通过HPB版本的javaSDK部署合约到HPB区块链然后调用智能合约
通过生成智能合约对应的java包装类面向对象式的运行智能合约
分别新建HPBToken.abi和HPBToken.bin文件并把以上复制的abi和bin代码复制到对应的文件中。
引入HPB的java SDk
<dependency>
<groupId>io.hpb.web3</groupId>
<artifactId>web3-hpb</artifactId>
<version>1.2.0</version>
</dependency>
//新建生成合约包装类GenContract
import java.util.Arrays;
import io.hpb.web3.codegen.SolidityFunctionWrapperGenerator;
public class GenContract {
public static void main(String[] args) {
try {
String SOLIDITY_TYPES_ARG = "--solidityTypes";
String packageName = "io.hpb.web3.contracts";
String outDirPath = "D:/contracts/java/";
String binDirPath = "D:/contracts/HPBToken.bin";
String abiDirPath = "D:/contracts/HPBToken.abi";
SolidityFunctionWrapperGenerator.main(Arrays.asList(SOLIDITY_TYPES_ARG,
binDirPath,
abiDirPath,
"-p", packageName, "-o", outDirPath).toArray(new String[0]));
} catch (Exception e) {
e.printStackTrace();
}
}
}
//生成后的类为HPBToken.java
//删除掉所有构造方法
protected HPBToken(String contractAddress, Web3 web3, Credentials credentials,
BigInteger gasPrice, BigInteger gasLimit) {
super(BINARY, contractAddress, web3, credentials, gasPrice, gasLimit);
}
protected HPBToken(String contractAddress, Web3 web3, TransactionManager transactionManager,BigInteger gasPrice, BigInteger gasLimit) {
super(BINARY, contractAddress, web3, transactionManager, gasPrice, gasLimit);
}
//添加新的构造方法
protected HPBToken(String contractAddress, Web3 web3, Credentials credentials,
BigInteger gasPrice, BigInteger gasLimit) {
super(BINARY, contractAddress, web3, new RawTransactionManager(web3, credentials), new StaticGasProvider(gasPrice, gasLimit));
}
protected HPBToken(String contractAddress, Web3 web3, TransactionManager transactionManager,BigInteger gasPrice, BigInteger gasLimit) {
super(BINARY, contractAddress, web3, transactionManager, new StaticGasProvider(gasPrice, gasLimit));
}
protected HPBToken(String contractAddress,
Web3 web3, TransactionManager transactionManager,ContractGasProvider gasProvider) {
super(BINARY, contractAddress, web3, transactionManager, gasProvider);
}
自行在本地建立HPB开发者节点，发布智能合约和调用智能合约，代码如下
private static final int WEB3J_TIMEOUT = 800;
public static void main(String[] args) throws Exception{
BigInteger gasPrice = Convert.toWei("18", Convert.Unit.GWEI).toBigInteger();
BigInteger gasLimit = new BigInteger("99000000");
Credentials credentials = WalletUtils.loadCredentials(password,keyStorePath);
Web3Service web3Service = buildService(clientAddress);
Admin admin = Admin.build(web3Service);
RawTransactionManager transactionManager=new RawTransactionManager(admin, credentials, ChainId.MAINNET);
Address _target=new Address(address);
HPBToken hpbTokenDeploy = HPBToken.deploy(admin, transactionManager, gasPrice, gasLimit, _target).
sendAsync().get(WEB3J_TIMEOUT, TimeUnit.MINUTES);
String contractAddress=hpbTokenDeploy.getContractAddress();
log.info("发布智能合约成功，合约地址为："+contractAddress);
HPBToken hpbToken = HPBToken.load(contractAddress, admin, transactionManager, gasPrice, gasLimit);
Bool bool = hpbToken.saleStarted().sendAsync().get(WEB3J_TIMEOUT, TimeUnit.MINUTES);
log.info(bool);
TransactionReceipt receipt = hpbToken.transfer(new Address("0x09fe745cff05b35cb06da6768586279018c08d7f"),
new Uint256(Convert.toWei("10", Convert.Unit.HPB).toBigInteger())).sendAsync()
.get(WEB3J_TIMEOUT, TimeUnit.MINUTES);
log.info(receipt.isStatusOK());
}
private static Web3Service buildService(String clientAddress) {
Web3Service Web3Service;
if (clientAddress == null || clientAddress.equals("")) {
Web3Service = new HttpService(createOkHttpClient());
} else if (clientAddress.startsWith("http")) {
Web3Service = new HttpService(clientAddress, createOkHttpClient(), false);
} else if (System.getProperty("os.name").toLowerCase().startsWith("win")) {
Web3Service = new WindowsIpcService(clientAddress);
} else {
Web3Service = new UnixIpcService(clientAddress);
}
return Web3Service;
}
private static OkHttpClient createOkHttpClient() {
OkHttpClient.Builder builder = new OkHttpClient.Builder();
configureLogging(builder);
configureTimeouts(builder);
return builder.build();
}
private static void configureTimeouts(OkHttpClient.Builder builder) {
builder.connectTimeout(WEB3J_TIMEOUT, TimeUnit.SECONDS);
builder.readTimeout(WEB3J_TIMEOUT, TimeUnit.SECONDS);
// Sets the socket timeout too
builder.writeTimeout(WEB3J_TIMEOUT, TimeUnit.SECONDS);
}
private static void configureLogging(OkHttpClient.Builder builder) {
if (log.isDebugEnabled()) {
HttpLoggingInterceptor logging = new HttpLoggingInterceptor(log::debug);
logging.setLevel(HttpLoggingInterceptor.Level.BODY);
builder.addInterceptor(logging);
}
}
2.6 通过PB版本的Web3js部署合约到HPB区块链然后调用智能合约
Web3.js实现部署和调用合约代码如下
var Web3ForHpb = require('web3_hpb');
var web3Hpb = new Web3ForHpb();
web3Hpb.setProvider(new web3Hpb.providers.HttpProvider("http://localhost:8545"));
web3Hpb.hpb.contract(abi).new({
data: '0x' + bytecode,
from: "",
gas: 1000000
}, (err, res) => {
if (err) {
console.log(err);
return;
}
console.log(res.transactionHash);
// If we have an address property, the contract was deployed
if (res.address) {
console.log('Contract address: ' + res.address);
}
});
var hpbTestContract = web3Hpb.hpb.contract(abi).at(contractAddress);
console.log(hpbTestContract.getContractAddr.call());
3 迁移总结
任何基于以太坊区块链的Dapp的合约代码都可以通过相同的流程平滑迁移到HPB的区块链上；复制原始智能合约代码，利用remix来重新编译，拷贝对应的编译好的bin和abi文件，通过HPB版本的javaSDK和HPB版本的web3js来发布和调用该DAPP的智能合约。