使用fabric-sdk-node的示例2

0 导言

fabric-sdk-node也是分两种写法，一种是底层写法，一种是比较高层的写法。下面先演示比较高层的写法。借助于fabric-network这个模块可以写更加简捷的代码。

本文档演示了一个汽车资产管理的例子，官方提供相应的链码和客户端示例代码。

1 创建项目目录

注：如果已经有该目录则不需创建了

$ cd $GOPATH/src/github.com
$ mkdir -p fabric-study/sdk-node-study1

注：如果上述mkdir 不能执行，可能是没有权限，加上sudo就可以了

$ sudo mkdir -p fabric-study/sdk-node-study1

2 搭建运行网络

我们不另行去搭建节点网络了，直接拷贝官网提供的basic-network过来用，执行cp命令进行拷贝.

$ cd fabric-study/sdk-node-study1/
$ cp -r ../../hyperledger/fabric-samples/basic-network ./

basic-network会创建如下节点

序号	组织	IP	域名	端口映射	节点
docker 容器1	无	172.18.0.6	orderer.example.com	0.0.0.0:9051->7051/tcp, 0.0.0.0:9053->7053/tcp	orderer节点
docker 容器2	组织1 - org1	172.18.0.7	peer0.org1.example.com	0.0.0.0:10051->7051/tcp, 0.0.0.0:10053->7053/tcp	peer1节点
docker 容器3	无	172.18.0.6	无	无	cli客户端
docker 容器4	无	172.18.0.6	无	无	couchDB服务器
docker 容器5	无	172.18.0.6	无	无	ca服务器

3 创建链码放置目录

在这里我们不打算自己编写链码了，直接使用官方提供的fabcar示例的链码，如若对该链码不了解，可通过阅读该链码的源码来熟悉它

$ mkdir chaincode
$ cp -r ../../hyperledger/fabric-samples/chaincode/fabcar ./chaincode

4 创建app1目录

$ mkdir app2

5 用vscode打开sdk-node-study2

Snipaste_2019-03-22_16-58-32.png

6 在app1下创建package.json

内容如下

{
    "name": "fabcar",
    "version": "1.0.0",
    "description": "FabCar application implemented in JavaScript",
    "engines": {
        "node": ">=8",
        "npm": ">=5"
    },
    "scripts": {
        "lint": "eslint .",
        "pretest": "npm run lint",
        "test": "nyc mocha --recursive"
    },
    "engineStrict": true,
    "author": "Hyperledger",
    "license": "Apache-2.0",
    "dependencies": {
        "fabric-ca-client": "~1.4.0",
        "fabric-network": "~1.4.0"
    },
    "devDependencies": {
        "chai": "^4.2.0",
        "eslint": "^5.9.0",
        "mocha": "^5.2.0",
        "nyc": "^13.1.0",
        "sinon": "^7.1.1",
        "sinon-chai": "^3.3.0"
    },
    "nyc": {
        "exclude": [
            "coverage/**",
            "test/**"
        ],
        "reporter": [
            "text-summary",
            "html"
        ],
        "all": true,
        "check-coverage": true,
        "statements": 100,
        "branches": 100,
        "functions": 100,
        "lines": 100
    }
}

7 创建enrollAdmin.js

该js脚本用来向ca-服务器注册管理员

'use strict';

//向ca服务器注册管理员
const FabricCAServices = require('fabric-ca-client');
const { FileSystemWallet, X509WalletMixin } = require('fabric-network');
const fs = require('fs');
const path = require('path');

//connection.json这个文件可以在basic-network文件夹找到，配置了一些连接的信息
const ccpPath = path.resolve(__dirname, '..', '..', 'basic-network', 'connection.json');
const ccpJSON = fs.readFileSync(ccpPath, 'utf8');
const ccp = JSON.parse(ccpJSON);

async function main() {
    try {

        // 创建一个CA客户端
        const caURL = ccp.certificateAuthorities['ca.example.com'].url;
        const ca = new FabricCAServices(caURL);

        // 创建一个wallet文件夹，用于管理身份.
        const walletPath = path.join(process.cwd(), 'wallet');
        const wallet = new FileSystemWallet(walletPath);
        console.log(`Wallet path: ${walletPath}`);

        // 检查是否已经注册管理员.
        const adminExists = await wallet.exists('admin');
        if (adminExists) {
            console.log('An identity for the admin user "admin" already exists in the wallet');
            return;
        }

        // 向ca服务器注册管理员,并将从服务器获得的身份证书导入到wallet.
        const enrollment = await ca.enroll({ enrollmentID: 'admin', enrollmentSecret: 'adminpw' });
        const identity = X509WalletMixin.createIdentity('Org1MSP', enrollment.certificate, enrollment.key.toBytes());
        wallet.import('admin', identity);
        console.log('Successfully enrolled admin user "admin" and imported it into the wallet');

    } catch (error) {
        console.error(`Failed to enroll admin user "admin": ${error}`);
        process.exit(1);
    }
}

main();

8 创建registerUser.js

该js脚本用来向fabric-ca服务器注册普通用户


'use strict';

//注册普通用户
const { FileSystemWallet, Gateway, X509WalletMixin } = require('fabric-network');
const fs = require('fs');
const path = require('path');

const ccpPath = path.resolve(__dirname, '..', '..', 'basic-network', 'connection.json');
const ccpJSON = fs.readFileSync(ccpPath, 'utf8');
const ccp = JSON.parse(ccpJSON);

async function main() {
    try {

        // 创建wallet文件夹用于管理身份信息.
        const walletPath = path.join(process.cwd(), 'wallet');
        const wallet = new FileSystemWallet(walletPath);
        console.log(`Wallet path: ${walletPath}`);

        // 检查是否已经注册过user1用户
        const userExists = await wallet.exists('user1');
        if (userExists) {
            console.log('An identity for the user "user1" already exists in the wallet');
            return;
        }

        // 检查是否已经注册了admin用户
        const adminExists = await wallet.exists('admin');
        if (!adminExists) {
            console.log('An identity for the admin user "admin" does not exist in the wallet');
            console.log('Run the enrollAdmin.js application before retrying');
            return;
        }

        // 创建一个用于连接peer节点的网关
        const gateway = new Gateway();
        await gateway.connect(ccp, { wallet, identity: 'admin', discovery: { enabled: false } });

        // 创建一个用于与ca 服务器交互的ca 客户端对象
        const ca = gateway.getClient().getCertificateAuthority();
        const adminIdentity = gateway.getCurrentIdentity();

        // 注册用户到ca服务器，并将从ca服务器获得的身份信息导入到wallet文件夹.
        const secret = await ca.register({ affiliation: 'org1.department1', enrollmentID: 'user1', role: 'client' }, adminIdentity);
        const enrollment = await ca.enroll({ enrollmentID: 'user1', enrollmentSecret: secret });
        const userIdentity = X509WalletMixin.createIdentity('Org1MSP', enrollment.certificate, enrollment.key.toBytes());
        wallet.import('user1', userIdentity);
        console.log('Successfully registered and enrolled admin user "user1" and imported it into the wallet');

    } catch (error) {
        console.error(`Failed to register user "user1": ${error}`);
        process.exit(1);
    }
}

main();

9 创建query.js

该js脚本用来查询汽车信息



'use strict';

//通过链码查询
const { FileSystemWallet, Gateway } = require('fabric-network');
const fs = require('fs');
const path = require('path');

const ccpPath = path.resolve(__dirname, '..', '..', 'basic-network', 'connection.json');
const ccpJSON = fs.readFileSync(ccpPath, 'utf8');
const ccp = JSON.parse(ccpJSON);

async function main() {
    try {

        // 创建一个用于管理身份的文件夹wallet
        const walletPath = path.join(process.cwd(), 'wallet');
        const wallet = new FileSystemWallet(walletPath);
        console.log(`Wallet path: ${walletPath}`);

        // 检查是否已经注册好普通用户user1
        const userExists = await wallet.exists('user1');
        if (!userExists) {
            console.log('An identity for the user "user1" does not exist in the wallet');
            console.log('Run the registerUser.js application before retrying');
            return;
        }

        // 创建一个用于与peer节点通信的网关对象
        const gateway = new Gateway();
        await gateway.connect(ccp, { wallet, identity: 'user1', discovery: { enabled: false } });

        // 获得我们的链码部署到的channel对象
        const network = await gateway.getNetwork('mychannel');

        // 通过链码名称获得智能合约对象
        const contract = network.getContract('fabcar');

        // 执行指定的交易.
        // queryCar 交易 - 需要1个参数, 例如: ('queryCar', 'CAR4')
        // queryAllCars 交易 - 不需要任何参数, 例如: ('queryAllCars')
        //注意，如果不修改状态使用evaluateTransaction
        const result = await contract.evaluateTransaction('queryAllCars');
        console.log(`Transaction has been evaluated, result is: ${result.toString()}`);

    } catch (error) {
        console.error(`Failed to evaluate transaction: ${error}`);
        process.exit(1);
    }
}

main();

10 创建invoke.js

该js脚本做invoke调用

'use strict';

//调用链码对应的函数
const { FileSystemWallet, Gateway } = require('fabric-network');
const fs = require('fs');
const path = require('path');

const ccpPath = path.resolve(__dirname, '..', '..', 'basic-network', 'connection.json');
const ccpJSON = fs.readFileSync(ccpPath, 'utf8');
const ccp = JSON.parse(ccpJSON);

async function main() {
    try {

        // 创建一个用于管理身份的文件夹wallet
        const walletPath = path.join(process.cwd(), 'wallet');
        const wallet = new FileSystemWallet(walletPath);
        console.log(`Wallet path: ${walletPath}`);

       // 检查是否已经注册好普通用户user1
        const userExists = await wallet.exists('user1');
        if (!userExists) {
            console.log('An identity for the user "user1" does not exist in the wallet');
            console.log('Run the registerUser.js application before retrying');
            return;
        }

      // 创建一个用于与peer节点通信的网关对象
        const gateway = new Gateway();
        await gateway.connect(ccp, { wallet, identity: 'user1', discovery: { enabled: false } });

         // 获得我们的链码部署到的channel对象
        const network = await gateway.getNetwork('mychannel');

        // 创建一个用于与peer节点通信的网关对象
        const contract = network.getContract('fabcar');

        // 提交特定的交易 .
        // createCar 交易 - 需要5个参数, 例如: ('createCar', 'CAR12', 'Honda', 'Accord', 'Black', 'Tom')
        // changeCarOwner 交易 - 需要2个参数 , 例如: ('changeCarOwner', 'CAR10', 'Dave')
        //注意，涉及到修改状态使用submitTransaction
        await contract.submitTransaction('createCar', 'CAR12', 'Honda', 'Accord', 'Black', 'Tom');
        console.log('Transaction has been submitted');

        // 断开网关连接
        await gateway.disconnect();

    } catch (error) {
        console.error(`Failed to submit transaction: ${error}`);
        process.exit(1);
    }
}

main();

11 启动网络

生成证书（注，只需要执行一次就ok了,以后都不用执行这一步了）

$ ./generate.sh

先停止到旧的网络


$ docker stop -f $(docker ps -aq)
$ docker rm -f $(docker ps -aq)
$ docker rmi -f $(docker images | grep fabcar | awk '{print $3}')

然后启动网络,该脚本只启动了ca、orderer、peer、couchDb这几个容器，没有启动cli容器。并且创建名字为mychannel的通道，随后还让peer0.Org1加入了该通道

$ rm -rf ./hfc-key-store
$ cd basic-network
$ ./start.sh

12 启动cli容器

$ docker-compose -f ./docker-compose.yml up -d cli

13 安装和实例化链码

打开一个新的终端，不用进入cli容器，可以在外边执行，用-exec表示在外边执行

安装链码

$ docker exec -e "CORE_PEER_LOCALMSPID=Org1MSP" -e "CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/[email protected]/msp" cli peer chaincode install -n fabcar -v 1.0 -p github.com/fabcar/go -l golang

实例化链码

$ docker exec -e "CORE_PEER_LOCALMSPID=Org1MSP" -e "CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/[email protected]/msp" cli peer chaincode instantiate -o orderer.example.com:7050 -C mychannel -n fabcar -l golang -v 1.0 -c '{"Args":[]}' -P "OR ('Org1MSP.member','Org2MSP.member')"

调用initLedger函数初始化账本

$ docker exec -e "CORE_PEER_LOCALMSPID=Org1MSP" -e "CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/[email protected]/msp" cli peer chaincode invoke -o orderer.example.com:7050 -C mychannel -n fabcar -c '{"function":"initLedger","Args":[]}'

14 进入app1目录安装依赖

到了这一步，证书已经生成，节点网络已经启动，链码也安装和实例化好了，接下来就来测试一下sdk的调用是否成功了。

进入app1目录,并执行npm install安装依赖模块

$ cd app1
$ npm install

15 注册管理员

$ node enrollAdmin.js

输出如下信息

Store path:/home/bob/go/src/github.com/fabric-study/sdk-node-study1/app1/hfc-key-store
Successfully enrolled admin user "admin"
Assigned the admin user to the fabric client ::{"name":"admin","mspid":"Org1MSP","roles":null,"affiliation":"","enrollmentSecret":"","enrollment":{"signingIdentity":"607d571669d90da409ebdaec5855e3a395bbf7af5aab200cd5a902a4054c9cb0","identity":{"certificate":"-----BEGIN CERTIFICATE-----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\ns2PyHQIgS54OqyzJ0kulh/xyHd9IkDRAM2iJPVsxCzMUP+t/C1s=\n-----END CERTIFICATE-----\n"}}}

16 注册普通用户

$ node register.js