五、Fabric2.4.6 在java应用访问智能合约（ubun

四、Fabric2.4.6 智能合约(java)（ubuntu 22.04）

1、pom.xml 引入依赖

# pom.xml中加入fabric依赖
        <dependency>
            <groupId>org.hyperledger.fabric-sdk-java</groupId>
            <artifactId>fabric-sdk-java</artifactId>
            <version>2.2.12</version>
        </dependency>
        <dependency>
            <groupId>org.hyperledger.fabric</groupId>
            <artifactId>fabric-gateway</artifactId>
            <version>1.0.1</version>
        </dependency>

2、拷贝crypto-config

# 拷贝身份信息文件 crypto-config 到resources目录下

3、用户身份配置

# application.properties
# 下面配置是用哪个用户连接到网络

fabric.mspId=Org1MSP

# 证书路径
fabric.certificatePath=src/main/resources/crypto-config/peerOrganizations/org1.supervisor.com/users/User1@org1.supervisor.com/msp/signcerts/User1@org1.supervisor.com-cert.pem
# 私钥路径
fabric.privateKeyPath=src/main/resources/crypto-config/peerOrganizations/org1.supervisor.com/users/User1@org1.supervisor.com/msp/keystore/priv_sk
# tls证书路径
fabric.tlsCertPath=src/main/resources/crypto-config/peerOrganizations/org1.supervisor.com/peers/peer0.org1.supervisor.com/tls/ca.crt
# 通道
fabric.channel=mychannel

logging.level.org.hyperledger=trace

4、增加属性类

# 在FabricContractApiApplication 启动类，需要加入@EnableConfigurationProperties注解，否则程序启动读取不到appliation.properties属性；

@Configuration
@ConfigurationProperties(prefix = "fabric")
@Data
public class HyperLedgerFabricProperties {

    String mspId;

    String certificatePath;

    String privateKeyPath;

    String tlsCertPath;

    String channel;

}

5、gateway配置

@Configuration
@AllArgsConstructor
@Slf4j
public class HyperLedgerFabricGatewayConfig {

    @Autowired
    final HyperLedgerFabricProperties hyperLedgerFabricProperties;

    @Bean
    public Gateway gateway() throws Exception {

        BufferedReader certificateReader = Files.newBufferedReader(Paths.get(hyperLedgerFabricProperties.getCertificatePath()), StandardCharsets.UTF_8);

        X509Certificate certificate = Identities.readX509Certificate(certificateReader);

        BufferedReader privateKeyReader = Files.newBufferedReader(Paths.get(hyperLedgerFabricProperties.getPrivateKeyPath()), StandardCharsets.UTF_8);

        PrivateKey privateKey = Identities.readPrivateKey(privateKeyReader);

        Gateway gateway = Gateway.newInstance()
                .identity(new X509Identity(hyperLedgerFabricProperties.getMspId() , certificate))
                .signer(Signers.newPrivateKeySigner(privateKey))
                .connection(newGrpcConnection())
                .evaluateOptions(CallOption.deadlineAfter(5, TimeUnit.SECONDS))
                .endorseOptions(CallOption.deadlineAfter(15, TimeUnit.SECONDS))
                .submitOptions(CallOption.deadlineAfter(5, TimeUnit.SECONDS))
                .commitStatusOptions(CallOption.deadlineAfter(1, TimeUnit.MINUTES))
                .connect();

        log.info("=========================================== connected fabric gateway {} " , gateway);

        return gateway;
    }

    private ManagedChannel newGrpcConnection() throws IOException, CertificateException {
        Reader tlsCertReader = Files.newBufferedReader(Paths.get(hyperLedgerFabricProperties.getTlsCertPath()));
        X509Certificate tlsCert = Identities.readX509Certificate(tlsCertReader);
        // fabric 2.4以后，支持连接一个节点即可；
        return NettyChannelBuilder.forTarget("peer0.org1.supervisor.com:7051")
                .sslContext(GrpcSslContexts.forClient().trustManager(tlsCert).build())
                .overrideAuthority("peer0.org1.supervisor.com")
                .build();
    }

    @Bean
    public Network network(Gateway gateway) {
        return gateway.getNetwork(hyperLedgerFabricProperties.getChannel());
    }

    @Bean
    public Contract hashInfoContract(Network network) {
        // fabric-smart-contract 链码
        // HashInfoContract 合约
        return network.getContract("fabric-smart-contract" , "HashInfoContract");
    }

    @Bean
    public ChaincodeEventListener chaincodeEventListener(Network network) {
        return new ChaincodeEventListener(network);
    }
}

6、事件监听

@Slf4j
public class ChaincodeEventListener implements Runnable{

    final Network network;

    public ChaincodeEventListener(Network network) {
        this.network = network;

        ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(1, new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
                Thread thread = new Thread(r);
                thread.setDaemon(true);
                thread.setName(this.getClass() + "chaincode_event_listener");
                return thread;
            }
        });

        executor.execute(this);
    }

    @Override
    public void run() {
        CloseableIterator<ChaincodeEvent> events = network.getChaincodeEvents("fabric-smart-contract");
        log.info("chaincodeEvents {} " , events);

        // events.hasNext() 会阻塞等待
        while (events.hasNext()) {
            ChaincodeEvent event = events.next();
            log.info("receive chaincode event {} , transaction id {} ,  block number {} , payload {} "
                    , event.getEventName() , event.getTransactionId() , event.getBlockNumber() , StringUtils.newStringUtf8(event.getPayload()));
        }
    }
}

# 在java应用访问智能合约
# git地址：https://gitee.com/baihu_shusheng/fabric-contract-api.git

六、Fabric2.4.6 prometheus & grafana 监控网络 （ubuntu 22.04）

参考：
https://www.bilibili.com/video/BV1eS4y1L7Zo/?spm_id_from=333.788.recommend_more_video.2&vd_source=ef83736476a46166544cd38458b6b130

https://www.bilibili.com/video/BV1yR4y1G7fZ/?spm_id_from=333.337.search-card.all.click&vd_source=ef83736476a46166544cd38458b6b130

https://github.com/hyperledger/fabric-gateway-java/
https://github.com/hyperledger/fabric-gateway