[区块链]Fisco开发第一个区块链应用

一、部署区块链

1. 环境准备

第一步：安装JDK 1.8版本。

第二步：下载fisco压缩包。

链接：https://pan.baidu.com/s/1_ivw1FeKVhbVZIAbzvdSQg 
提取码：e14j

下载完成后解压缩到/root目录下。

2. 启动节点

1）启动区块链节点：

cd /root/fisco/nodes/127.0.0.1/
sh start_all.sh

确认节点启动正常：

tail -f /root/fisco/nodes/127.0.0.1/node0/log/log*  | grep +++

正常情况会不停输出++++Generating seal，表示共识正常。

2）启动节点控制台服务：

cd /root/fisco/WeBASE-Front/dist
sh start.sh

通过浏览器远程访问如下链接，如果可以访问，则说明已经正常运行了。

http://ip:5002/WeBASE-Front/

界面如下所示：

3. 编译合约

１）准备合约

pragma solidity ^0.4.21;

contract Asset {
    address public issuer;
    mapping (address => uint) public balances;

    event Sent(address from, address to, uint amount);

    constructor() {
        issuer = msg.sender;
    }

    function issue(address receiver, uint amount) public {
        if (msg.sender != issuer) return;
        balances[receiver] += amount;
    }

    function send(address receiver, uint amount) public {
        if (balances[msg.sender] < amount) return;
        balances[msg.sender] -= amount;
        balances[receiver] += amount;
        emit Sent(msg.sender, receiver, amount);
    }
    
}

2）部署合约

选择合约IDE，点右上角“部署”按钮。部署成功后，会生成合约地址（如下图所示）。

3）下载SDK证书

点击右上角的“SDK证书下载”按钮，将下载的证书压缩包文件保存起来，后面需要导入到项目中。

4. 创建测试用户

点击左边“测试用户”菜单，在主界面上点击“新增用户”，然后输入用户名。

点击新建用户右边的导出按钮，选择.pem，导出用户证书。

二、创建应用

1. 新建项目

本示例所使用开发工具为Idea。首先新建一个Maven项目。然后按照下面目录结构在src/main/java和src/main/resources中创建相应的包和文件夹。

将上面准备好的用户证书和sdk证书分别复制到对应文件夹中（如下图所示）。

2. 引入依赖

pom文件如下所示：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.fisco.bcos</groupId>
    <artifactId>asset-app</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <version>2.7.3</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <version>2.6.8</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.fisco-bcos.java-sdk</groupId>
            <artifactId>fisco-bcos-java-sdk</artifactId>
            <version>2.9.1</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

3. 启动类

在org.fisco.bcos.asset包下创建启动类。

@SpringBootApplication
public class Application
{
    public static void main(String[] args)
    {
        SpringApplication.run(Application.class, args);
        System.out.println("项目启动成功");
    }
}

4. 导出Java文件

点击节点控制台上的合约IDE，然后选中Asset.sol合约后，点击上方的导出Java文件。

然后将导出的Java文件拷贝到项目的org.fisco.bcos.asset.contract包下。

5. 定义区块链配置信息

在src/main/resources目录下，新建application.yaml文件。

fisco:
  nodeList: 192.168.88.15:20201
  groupId: 1
  certPath: E:\workspace\asset-app\src\main\resources\sdk
  contractAddress:
    # Asset合约地址(一定要加引号 不然注解@Value会把按照16进制数字进行转换赋值)
    asset: "0xe755337500bb6ffad292a2499bc12e30d5dc744f"
  # 账户地址
  account:
    # 账户秘钥地址
    accountAddress: E:\workspace\asset-app\src\main\resources\account
    # 账户文件地址
    accountFilePath: E:\workspace\asset-app\src\main\resources\account\zhongliwen_key_0x6e26d380588049b43efca3881a2b2c419ae1a118.pem

fisco.nodeList：区块链节点的ip和端口；
fisco.groupId：组ID；
fisco.certPath：证书保存目录；
fisco.contractAddress.asset：合约地址；
fisco.contractAddress.account.accountAddress：测试用户地址；
fisco.contractAddress.account.accountFilePath：用户密码文件地址；

6. 编写sdk访问合约方法

在org.fisco.bcos.asset.client包下新建一个类，该类用于配置相关Bean。

package org.fisco.bcos.asset.client;

import org.fisco.bcos.sdk.BcosSDK;
import org.fisco.bcos.sdk.client.Client;
import org.fisco.bcos.sdk.config.ConfigOption;
import org.fisco.bcos.sdk.config.exceptions.ConfigException;
import org.fisco.bcos.sdk.config.model.ConfigProperty;
import org.fisco.bcos.sdk.crypto.CryptoSuite;
import org.fisco.bcos.sdk.crypto.keypair.CryptoKeyPair;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.security.KeyPair;
import java.util.*;

/**
 * @Description: 配置类
 * @Date: 2022/9/30
 * @Author: zhongliwen
 * @Version: 1.0
 */
@Configuration
public class ApplicationContext {

    @Value("${fisco.nodeList}")
    private String nodeLists;

    @Value("${fisco.groupId}")
    private Integer groupId;

    @Value("${fisco.certPath}")
    private String certPath;

    @Value("${fisco.account.accountFilePath}")
    private String accountFilePath;

    @Bean(name = "configProperty")
    public ConfigProperty defaultConfigProperty() {
        ConfigProperty property = new ConfigProperty();
        // 配置cryptoMaterial
        Map<String, Object> cryptoMaterialMap = new HashMap<>();
        cryptoMaterialMap.put("certPath", certPath);
        property.setCryptoMaterial(cryptoMaterialMap);

        // 配置network
        Map<String, Object> networkMap = new HashMap<>();
        String[] split = nodeLists.split(",");
        List<String> nodeList = Arrays.asList(split);
        networkMap.put("peers", nodeList);
        property.setNetwork(networkMap);

        // 配置account
        Map<String, Object> accountMap = new HashMap<>();
        accountMap.put("keyStoreDir", "account");
        accountMap.put("accountAddress", "");
        accountMap.put("accountFileFormat", "pem");
        accountMap.put("password", "");
        accountMap.put("accountFilePath", accountFilePath);
        property.setAccount(accountMap);

        //配置 threadPool
        Map<String, Object> threadPoolMap = new HashMap<>();
        threadPoolMap.put("channelProcessorThreadSize", "16");
        threadPoolMap.put("receiptProcessorThreadSize", "16");
        threadPoolMap.put("maxBlockingQueueSize", "102400");
        property.setThreadPool(threadPoolMap);
        return property;
    }

    @Bean(name = "configOption")
    public ConfigOption defaultConfigOption(ConfigProperty configProperty) throws ConfigException {
        return new ConfigOption(configProperty);
    }

    @Bean(name = "bcosSDK")
    public BcosSDK bcosSDK(ConfigOption configOption) {
        return new BcosSDK(configOption);
    }

    @Bean(name = "client")
    public Client getClient(BcosSDK bcosSDK) {
        // 为群组初始化client
        Client client = bcosSDK.getClient(groupId);
        return client;
    }

    @Bean
    public CryptoKeyPair getCryptoKeyPair(Client client) {
        // 如果有密钥文件 那么每次读取的就不再是随机的
        CryptoSuite cryptoSuite = client.getCryptoSuite();
        CryptoKeyPair cryptoKeyPair = cryptoSuite.getCryptoKeyPair();
        return cryptoKeyPair;
    }
}

然后再同样的包下创建另外一个类，该类定义了访问Asset合约的方法。

package org.fisco.bcos.asset.client;

import org.fisco.bcos.asset.contract.Asset;
import org.fisco.bcos.sdk.BcosSDK;
import org.fisco.bcos.sdk.client.Client;
import org.fisco.bcos.sdk.crypto.keypair.CryptoKeyPair;
import org.fisco.bcos.sdk.model.TransactionReceipt;
import org.fisco.bcos.sdk.model.callback.TransactionCallback;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

import java.math.BigInteger;

@Component
public class AssetClient {
    @Autowired
    private BcosSDK bcosSDK;
    @Autowired
    private Client client;
    @Autowired
    private CryptoKeyPair cryptoKeyPair;
    @Value("${fisco.contractAddress.asset}")
    private String contractAddress;

    /**
     * 发布资产（条件：当前用户是Asset合约发布者）
     * @param receiver 接收者地址
     * @param amount 资产数量
     */
    public void issueAsset(String receiver, BigInteger amount) {
        Asset asset = Asset.load(contractAddress, client, cryptoKeyPair);
        asset.issue(receiver, amount, new CallbackResponse());
    }

    /**
     * 发送资产（条件：发送者的账号Balance必须大于等于amount）
     * @param receiver 接收者地址
     * @param amount 资产数量
     */
    public void sendAsset(String receiver, BigInteger amount) {
        Asset asset = Asset.load(contractAddress, client, cryptoKeyPair);
        asset.send(receiver, amount, new CallbackResponse());
    }

    private class CallbackResponse extends TransactionCallback {

        @Override
        public void onResponse(TransactionReceipt transactionReceipt) {
            System.out.println("回调结果：");
            System.out.println(transactionReceipt.getContractAddress());
            System.out.println(transactionReceipt.getFrom());
            System.out.println(transactionReceipt.getGasUsed());
            System.out.println(transactionReceipt.getRemainGas());
            System.out.println(transactionReceipt.getStatus());
            System.out.println(transactionReceipt.getMessage());
            System.out.println(transactionReceipt.getStatusMsg());
        }
    }
}

关于Java SDK的使用手册，可以参考官方提供的文档。

https://fisco-bcos-documentation.readthedocs.io/zh_CN/latest/docs/sdk/java_sdk/index.html

7. 测试

编写一个单元测试类，分别对AssetClient类中的两个方法进行单元测试。

package org.fisco.bcos.asset.client;


import org.fisco.bcos.Application;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import java.math.BigInteger;

@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest(classes = Application.class)
public class AssetClientTest {
    @Autowired
    private AssetClient assetClient;

    @Test
    public void testIssueAsset() throws InterruptedException {
        String receiver = "0x6e26d380588049b43efca3881a2b2c419ae1a118";
        BigInteger amount = new BigInteger("10000");
        assetClient.issueAsset(receiver, amount);
        Thread.sleep(5000);
        System.out.println("发布成功！");
    }

    @Test
    public void testSendAsset() throws InterruptedException {
        String receiver = "0x0f16fe999788f945adcad08e5b8c4fb1fcfca55d";
        BigInteger amount = new BigInteger("50000");
        assetClient.sendAsset(receiver, amount);
        Thread.sleep(5000);
        System.out.println("发送成功！");
    }

}

测试步骤：

1. 先后执行testIssueAsset和testSendAsset测试方法；
2. 执行成功后，在节点控制台的合约列表中找到对应的合约；

3. 点击右方的合约调用，然后方法选择balances，参数输入测试方法中receiver地址；

点击确定后，可以看到相关的交易回执。

到目前为止，已经完成了在Fisco区块链上部署智能合约，并通过Java SDK调用智能合约函数的示例。