Hyperledger Fabric 2.x Java区块链应用

本是古典何须时尚 2023-10-01 19:33 15阅读 0赞

![3c9869822af5af1a79460912cad34f04.png][]

### 一、说明 ###

在上一篇文章中 [《Hyperledger Fabric 2.x 自定义智能合约》][Hyperledger Fabric 2.x] 分享了智能合约的安装并使用 `cli` 客户端进行合约的调用；本文将使用 `Java` 代码基于 `fabric-gateway-java` 进行区块链网络的访问与交易，并集成 `SpringBoot` 框架。

`Fabric Gateway SDK` 实现Fabric的编程模型，提供了一系列简单的API给应用程序与Fabric区块链网络进行交互；

网络拓扑图：

![watermark_type_d3F5LXplbmhlaQ_shadow_50_text_Q1NETiBAdXVxYXo_size_20_color_FFFFFF_t_70_g_se_x_16][] 应用程序将各自的网络交互委托给其网关，每个网关都了解网络信道拓扑，包括组织的多个Peer节点和排序节点，使应用程序专注于业务逻辑；Peer节点可以使用gossip协议在组织内部和组织之间相互通信。

### 二、Mavn依赖 ###

添加网关sdk的依赖：

<dependency>
    		<groupId>org.hyperledger.fabric</groupId>
    		<artifactId>fabric-gateway-java</artifactId>
    		<version>2.2.3</version>
    </dependency>

### 三、准备配置文件 ###

工程的目录结构如下图所示：

![watermark_type_d3F5LXplbmhlaQ_shadow_50_text_Q1NETiBAdXVxYXo_size_15_color_FFFFFF_t_70_g_se_x_16][]

#### 3.1. 准备网络证书 ####

创建目录 `crypto-config` 把 `orderer` 和 `peer` 节点的证书文件复制进来。

证书文件从 `fabric-samples` 的 `test-network` 目录中复制 `ordererOrganizations` 与 `peerOrganizations` 文件夹：![watermark_type_d3F5LXplbmhlaQ_shadow_50_text_Q1NETiBAdXVxYXo_size_20_color_FFFFFF_t_70_g_se_x_16 1][]

#### 3.2. 创建网络配置 ####

创建文件 `connection.json` 内容如下：

{
        "name": "basic-network",
        "version": "1.0.0",
        "client": {
            "organization": "Org1",
            "connection": {
                "timeout": {
                    "peer": {
                        "endorser": "300"
                    },
                    "orderer": "300"
                }
            }
        },
        "channels": {
            "mychannel": {
                "orderers": [
                    "orderer.example.com"
                ],
                "peers": {
                    "peer0.org1.example.com": {
                        "endorsingPeer": true,
                        "chaincodeQuery": true,
                        "ledgerQuery": true,
                        "eventSource": true
                    },
                    "peer0.org2.example.com": {
                        "endorsingPeer": true,
                        "chaincodeQuery": true,
                        "ledgerQuery": true,
                        "eventSource": true
                    }
                }
            }
        },
        "organizations": {
            "Org1": {
                "mspid": "Org1MSP",
                "peers": [
                    "peer0.org1.example.com"
                ],
                "certificateAuthorities": [
                    "ca-org1"
                ],
                "adminPrivateKeyPEM": {
                    "path": "src/main/resources/crypto-config/peerOrganizations/org1.example.com/users/Admin@org1.example.com/msp/keystore/priv_sk"
                },
                "signedCertPEM": {
                    "path": "src/main/resources/crypto-config/peerOrganizations/org1.example.com/users/Admin@org1.example.com/msp/signcerts/Admin@org1.example.com-cert.pem"
                }
            },
            "Org2": {
                "mspid": "Org2MSP",
                "peers": [
                    "peer0.org2.example.com"
                ],
                "certificateAuthorities": [
                    "ca-org2"
                ],
                "adminPrivateKeyPEM": {
                    "path": "src/main/resources/crypto-config/peerOrganizations/org2.example.com/users/Admin@org2.example.com/msp/keystore/priv_sk"
                },
                "signedCertPEM": {
                    "path": "src/main/resources/crypto-config/peerOrganizations/org2.example.com/users/Admin@org2.example.com/msp/signcerts/Admin@org2.example.com-cert.pem"
                }
            }
        },
        "orderers": {
            "orderer.example.com": {
                "url": "grpcs://192.168.28.134:7050",
                "mspid": "OrdererMSP",
                "grpcOptions": {
                    "ssl-target-name-override": "orderer.example.com",
                    "hostnameOverride": "orderer.example.com"
                },
                "tlsCACerts": {
                    "path": "src/main/resources/crypto-config/ordererOrganizations/example.com/orderers/orderer.example.com/tls/ca.crt"
                },
                "adminPrivateKeyPEM": {
                    "path": "src/main/resources/crypto-config/ordererOrganizations/example.com/users/Admin@example.com/msp/keystore/priv_sk"
                },
                "signedCertPEM": {
                    "path": "src/main/resources/crypto-config/ordererOrganizations/example.com/users/Admin@example.com/msp/signcerts/Admin@example.com-cert.pem"
                }
            }
        },
        "peers": {
            "peer0.org1.example.com": {
                "url": "grpcs://192.168.28.134:7051",
                "grpcOptions": {
                    "ssl-target-name-override": "peer0.org1.example.com",
                    "hostnameOverride": "peer0.org1.example.com",
                    "request-timeout": 120001
                },
                "tlsCACerts": {
                    "path": "src/main/resources/crypto-config/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt"
                }
            },
            "peer0.org2.example.com": {
                "url": "grpcs://192.168.28.134:9051",
                "grpcOptions": {
                    "ssl-target-name-override": "peer0.org2.example.com",
                    "hostnameOverride": "peer0.org2.example.com",
                    "request-timeout": 120001
                },
                "tlsCACerts": {
                    "path": "src/main/resources/crypto-config/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt"
                }
            }
        },
        "certificateAuthorities": {
            "ca-org1": {
                "url": "https://192.168.28.134:7054",
                "grpcOptions": {
                    "verify": true
                },
                "tlsCACerts": {
                    "path": "src/main/resources/crypto-config/peerOrganizations/org1.example.com/ca/ca.org1.example.com-cert.pem"
                },
                "registrar": [
                    {
                        "enrollId": "admin",
                        "enrollSecret": "adminpw"
                    }
                ]
            },
            "ca-org2": {
                "url": "https://192.168.28.134:8054",
                "grpcOptions": {
                    "verify": true
                },
                "tlsCACerts": {
                    "path": "src/main/resources/crypto-config/peerOrganizations/org2.example.com/ca/ca.org2.example.com-cert.pem"
                },
                "registrar": [
                    {
                        "enrollId": "admin",
                        "enrollSecret": "adminpw"
                    }
                ]
            }
        }
    }

需按实际情况修改url中的地址，内容中分别包含了 `channels`、`organizations`、`orderers`、`peers`、`ca` 的配置

#### 3.3. SpringBoot配置 ####

在 `application.yml` 中添加以下内容，用于访问网关的相关配置：

fabric:
      # wallet文件夹路径(自动创建)
      walletDirectory: wallet
      # 网络配置文件路径
      networkConfigPath: connection.json
      # 用户证书路径
      certificatePath: crypto-config/peerOrganizations/org1.example.com/users/User1@org1.example.com/msp/signcerts/User1@org1.example.com-cert.pem
      # 用户私钥路径
      privateKeyPath: crypto-config/peerOrganizations/org1.example.com/users/User1@org1.example.com/msp/keystore/priv_sk
      # 访问的组织名
      mspid: Org1MSP
      # 用户名
      username: user1
      # 通道名字
      channelName: mychannel
      # 链码名字
      contractName: mycc

### 四、连接合约 ###

分别构建网关、通道和合约的Bean对象，代码如下：

/**
     * 连接网关
     */
    @Bean
    public Gateway connectGateway() throws IOException, InvalidKeyException, CertificateException {
    		//使用org1中的user1初始化一个网关wallet账户用于连接网络
    		Wallet wallet = Wallets.newFileSystemWallet(Paths.get(this.walletDirectory));
    		X509Certificate certificate = readX509Certificate(Paths.get(this.certificatePath));
    		PrivateKey privateKey = getPrivateKey(Paths.get(this.privateKeyPath));
    		wallet.put(username, Identities.newX509Identity(this.mspid, certificate, privateKey));
    
    		//根据connection.json 获取Fabric网络连接对象
    		Gateway.Builder builder = Gateway.createBuilder()
    						.identity(wallet, username)
    						.networkConfig(Paths.get(this.networkConfigPath));
    
    		//连接网关
    		return builder.connect();
    }
    
    /**
     * 获取通道
     */
    @Bean
    public Network network(Gateway gateway) {
    		return gateway.getNetwork(this.channelName);
    }
    
    /**
     * 获取合约
     */
    @Bean
    public Contract contract(Network network) {
    		return network.getContract(this.contractName);
    }

### 五、合约调用 ###

创建controller类，注入Contract对象调用合约方法：

@Resource
    private Contract contract;
    
    @Resource
    private Network network;
    
    @GetMapping("/getUser")
    public String getUser(String userId) throws ContractException {
    		byte[] queryAResultBefore = contract.evaluateTransaction("getUser",userId);
    		return new String(queryAResultBefore, StandardCharsets.UTF_8);
    }
    
    @GetMapping("/addUser")
    public String addUser(String userId, String userName, String money) throws ContractException, InterruptedException, TimeoutException {
    		byte[] invokeResult = contract.createTransaction("addUser")
    						.setEndorsingPeers(network.getChannel().getPeers(EnumSet.of(Peer.PeerRole.ENDORSING_PEER)))
    						.submit(userId, userName, money);
    		String txId = new String(invokeResult, StandardCharsets.UTF_8);
    		return txId;
    }

### 六、测试接口 ###

> 调用接口 `getUser`：[http://127.0.0.1:9001/getUser?userId=1][http_127.0.0.1_9001_getUser_userId_1]

{
      "money": 300,
      "name": "zlt",
      "userId": "1"
    }

调用接口 `addUser`：[http://127.0.0.1:9001/addUser?userId=6&userName=test6&money=600][http_127.0.0.1_9001_addUser_userId_6_userName_test6_money_600]

2ae291bb6a366b5ba01ad49e4237da8def9e9828cc2c982e8c49d4b763af0157

### 七、代码下载 ###

gitee：[my-fabric-application-java: Hyperledger Fabric 2.x SpringBoot区块链应用：使用 Java 代码基于 fabric-gateway-java 进行区块链网络的访问与交易并集成 SpringBoot 框架。][my-fabric-application-java_ Hyperledger Fabric 2.x SpringBoot_ Java _ fabric-gateway-java _ SpringBoot]

github：[https://github.com/zlt2000/my-fabric-application-java][https_github.com_zlt2000_my-fabric-application-java]

[3c9869822af5af1a79460912cad34f04.png]: https://img-blog.csdnimg.cn/img_convert/3c9869822af5af1a79460912cad34f04.png
[Hyperledger Fabric 2.x]: https://mp.weixin.qq.com/s/ZgP5qamh_itqE2JNb3SXIQ
[watermark_type_d3F5LXplbmhlaQ_shadow_50_text_Q1NETiBAdXVxYXo_size_20_color_FFFFFF_t_70_g_se_x_16]: https://img-blog.csdnimg.cn/43603cc1b00e4513bbe0339402ea5e21.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBAdXVxYXo=,size_20,color_FFFFFF,t_70,g_se,x_16
[watermark_type_d3F5LXplbmhlaQ_shadow_50_text_Q1NETiBAdXVxYXo_size_15_color_FFFFFF_t_70_g_se_x_16]: https://img-blog.csdnimg.cn/2a5ab89dbe32418fac51c9114ef4c521.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBAdXVxYXo=,size_15,color_FFFFFF,t_70,g_se,x_16
[watermark_type_d3F5LXplbmhlaQ_shadow_50_text_Q1NETiBAdXVxYXo_size_20_color_FFFFFF_t_70_g_se_x_16 1]: https://img-blog.csdnimg.cn/e0c83db1471449929ef2ea2cd71f0142.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBAdXVxYXo=,size_20,color_FFFFFF,t_70,g_se,x_16
[http_127.0.0.1_9001_getUser_userId_1]: http://127.0.0.1:9001/getUser?userId=1
[http_127.0.0.1_9001_addUser_userId_6_userName_test6_money_600]: http://127.0.0.1:9001/addUser?userId=6&userName=test6&money=600
[my-fabric-application-java_ Hyperledger Fabric 2.x SpringBoot_ Java _ fabric-gateway-java _ SpringBoot]: https://gitee.com/zlt2000/my-fabric-application-java
[https_github.com_zlt2000_my-fabric-application-java]: https://github.com/zlt2000/my-fabric-application-java