编写nodejs代码

这部分内容参考：https://www.jianshu.com/p/a671c3002b64 并作为简化

先在github.com目录下创建一个项目目录，名叫xiaowei-app

cd $GOPATH/src/github.com/
mkdir -p fabric-sdk/xiaowei-app
cd fabric-sdk/xiaowei-app

然后在这个目录创建几个js文件

1、新建 package.json

{
    "name": "fabcar",
    "version": "1.0.0",
    "description": "汽车资产管理应用",
    "main": "fabcar.js",
    "scripts": {
        "test": "echo "Error: no test specified" && exit 1"
    },
    "dependencies": {
        "fabric-ca-client": "~1.4.0",
        "fabric-client": "~1.4.0",
        "grpc": "^1.6.0"
    },
    "author": "小韦云",
    "license": "Apache-2.0",
    "keywords": []
}

2、新建 enrollAdmin.js

'use strict';


 // 注册管理员用户


var Fabric_Client = require('fabric-client');
var Fabric_CA_Client = require('fabric-ca-client');

var path = require('path');
var util = require('util');
var os = require('os');


var fabric_client = new Fabric_Client();
var fabric_ca_client = null;
var admin_user = null;
var member_user = null;
var store_path = path.join(__dirname, 'hfc-key-store');
console.log(' Store path:'+store_path);


Fabric_Client.newDefaultKeyValueStore({ path: store_path
}).then((state_store) => {

    fabric_client.setStateStore(state_store);
    var crypto_suite = Fabric_Client.newCryptoSuite();


    var crypto_store = Fabric_Client.newCryptoKeyStore({path: store_path});
    crypto_suite.setCryptoKeyStore(crypto_store);
    fabric_client.setCryptoSuite(crypto_suite);
    var tlsOptions = {
        trustedRoots: [],
        verify: false
    };

    fabric_ca_client = new Fabric_CA_Client('http://localhost:7054', tlsOptions , 'ca.example.com', crypto_suite);


    return fabric_client.getUserContext('admin', true);
}).then((user_from_store) => {
    if (user_from_store && user_from_store.isEnrolled()) {
        console.log('Successfully loaded admin from persistence');
        admin_user = user_from_store;
        return null;
    } else {

        return fabric_ca_client.enroll({
          enrollmentID: 'admin',
          enrollmentSecret: 'adminpw'
        }).then((enrollment) => {
          console.log('Successfully enrolled admin user "admin"');
          return fabric_client.createUser(
              {username: 'admin',
                  mspid: 'Org1MSP',
                  cryptoContent: { privateKeyPEM: enrollment.key.toBytes(), signedCertPEM: enrollment.certificate }
              });
        }).then((user) => {
          admin_user = user;
          return fabric_client.setUserContext(admin_user);
        }).catch((err) => {
          console.error('Failed to enroll and persist admin. Error: ' + err.stack ? err.stack : err);
          throw new Error('Failed to enroll admin');
        });
    }
}).then(() => {
    console.log('Assigned the admin user to the fabric client ::' + admin_user.toString());
}).catch((err) => {
    console.error('Failed to enroll admin: ' + err);
});

3、新建 registerUser.js.

 //注册普通用户

var Fabric_Client = require('fabric-client');
var Fabric_CA_Client = require('fabric-ca-client');

var path = require('path');
var util = require('util');
var os = require('os');


var fabric_client = new Fabric_Client();
var fabric_ca_client = null;
var admin_user = null;
var member_user = null;
var store_path = path.join(__dirname, 'hfc-key-store');
console.log(' Store path:'+store_path);


Fabric_Client.newDefaultKeyValueStore({ path: store_path
}).then((state_store) => {

    fabric_client.setStateStore(state_store);
    var crypto_suite = Fabric_Client.newCryptoSuite();


    var crypto_store = Fabric_Client.newCryptoKeyStore({path: store_path});
    crypto_suite.setCryptoKeyStore(crypto_store);
    fabric_client.setCryptoSuite(crypto_suite);
    var tlsOptions = {
        trustedRoots: [],
        verify: false
    };

    fabric_ca_client = new Fabric_CA_Client('http://localhost:7054', null , '', crypto_suite);


    return fabric_client.getUserContext('admin', true);
}).then((user_from_store) => {
    if (user_from_store && user_from_store.isEnrolled()) {
        console.log('Successfully loaded admin from persistence');
        admin_user = user_from_store;
    } else {
        throw new Error('Failed to get admin.... run enrollAdmin.js');
    }



    return fabric_ca_client.register({enrollmentID: 'user1', affiliation: 'org1.department1',role: 'client'}, admin_user);
}).then((secret) => {

    console.log('Successfully registered user1 - secret:'+ secret);

    return fabric_ca_client.enroll({enrollmentID: 'user1', enrollmentSecret: secret});
}).then((enrollment) => {
  console.log('Successfully enrolled member user "user1" ');
  return fabric_client.createUser(
     {username: 'user1',
     mspid: 'Org1MSP',
     cryptoContent: { privateKeyPEM: enrollment.key.toBytes(), signedCertPEM: enrollment.certificate }
     });
}).then((user) => {
     member_user = user;

     return fabric_client.setUserContext(member_user);
}).then(()=>{
     console.log('User1 was successfully registered and enrolled and is ready to interact with the fabric network');

}).catch((err) => {
    console.error('Failed to register: ' + err);
    if(err.toString().indexOf('Authorization') > -1) {
        console.error('Authorization failures may be caused by having admin credentials from a previous CA instance.n' +
        'Try again after deleting the contents of the store directory '+store_path);
    }
});

4、新建 query.js

'use strict';


 //通过链码查询

var Fabric_Client = require('fabric-client');
var path = require('path');
var util = require('util');
var os = require('os');


var fabric_client = new Fabric_Client();


var channel = fabric_client.newChannel('mychannel');
var peer = fabric_client.newPeer('grpc://localhost:7051');
channel.addPeer(peer);


var member_user = null;
var store_path = path.join(__dirname, 'hfc-key-store');
console.log('Store path:'+store_path);
var tx_id = null;


Fabric_Client.newDefaultKeyValueStore({ path: store_path
}).then((state_store) => {

    fabric_client.setStateStore(state_store);
    var crypto_suite = Fabric_Client.newCryptoSuite();


    var crypto_store = Fabric_Client.newCryptoKeyStore({path: store_path});
    crypto_suite.setCryptoKeyStore(crypto_store);
    fabric_client.setCryptoSuite(crypto_suite);


    return fabric_client.getUserContext('user1', true);
}).then((user_from_store) => {
    if (user_from_store && user_from_store.isEnrolled()) {
        console.log('Successfully loaded user1 from persistence');
        member_user = user_from_store;
    } else {
        throw new Error('Failed to get user1.... run registerUser.js');
    }



    const request = {

        chaincodeId: 'fabcar',
        fcn: 'queryAllCars',
        args: ['']
    };


    return channel.queryByChaincode(request);
}).then((query_responses) => {
    console.log("Query has completed, checking results");

    if (query_responses && query_responses.length == 1) {
        if (query_responses[0] instanceof Error) {
            console.error("error from query = ", query_responses[0]);
        } else {
            console.log("Response is ", query_responses[0].toString());
        }
    } else {
        console.log("No payloads were returned from query");
    }
}).catch((err) => {
    console.error('Failed to query successfully :: ' + err);
});

5、新建 invoke.js

'use strict';
//调用链码
var Fabric_Client = require('fabric-client');
var path = require('path');
var util = require('util');
var os = require('os');
var fabric_client = new Fabric_Client();
var channel = fabric_client.newChannel('mychannel');
var peer = fabric_client.newPeer('grpc://localhost:7051');
channel.addPeer(peer);
var order = fabric_client.newOrderer('grpc://localhost:7050')
channel.addOrderer(order);
var member_user = null;
var store_path = path.join(__dirname, 'hfc-key-store');
console.log('Store path:' + store_path);
var tx_id = null;
Fabric_Client.newDefaultKeyValueStore({
    path: store_path
}).then((state_store) => {
    fabric_client.setStateStore(state_store);
    var crypto_suite = Fabric_Client.newCryptoSuite();
    var crypto_store = Fabric_Client.newCryptoKeyStore({ path: store_path });
    crypto_suite.setCryptoKeyStore(crypto_store);
    fabric_client.setCryptoSuite(crypto_suite);
    return fabric_client.getUserContext('user1', true);
}).then((user_from_store) => {
    if (user_from_store && user_from_store.isEnrolled()) {
        console.log('Successfully loaded user1 from persistence');
        member_user = user_from_store;
    } else {
        throw new Error('Failed to get user1.... run registerUser.js');
    }
    tx_id = fabric_client.newTransactionID();
    console.log("Assigning transaction_id: ", tx_id._transaction_id);
    var request = {
        chaincodeId: 'fabcar',
        fcn: 'createCar',
        args: ['CAR12', 'Honda', 'Accord', 'Black', 'Tom'],
        chainId: 'mychannel',
        txId: tx_id
    };
    return channel.sendTransactionProposal(request);
}).then((results) => {
    var proposalResponses = results[0];
    var proposal = results[1];
    let isProposalGood = false;
    if (proposalResponses && proposalResponses[0].response &&
        proposalResponses[0].response.status === 200) {
        isProposalGood = true;
        console.log('Transaction proposal was good');
    } else {
        console.error('Transaction proposal was bad');
    }
    if (isProposalGood) {
        console.log(util.format(
            'Successfully sent Proposal and received ProposalResponse: Status - %s, message - "%s"',
            proposalResponses[0].response.status, proposalResponses[0].response.message));
        var request = {
            proposalResponses: proposalResponses,
            proposal: proposal
        };
        var transaction_id_string = tx_id.getTransactionID();
        var promises = []; var sendPromise = channel.sendTransaction(request);
        promises.push(sendPromise);
        let txPromise = new Promise((resolve, reject) => {
            let handle = setTimeout(() => {
                event_hub.unregisterTxEvent(transaction_id_string);
                event_hub.disconnect();
                resolve({ event_status: 'TIMEOUT' });
            }, 3000);
            event_hub.registerTxEvent(transaction_id_string, (tx, code) => {
                clearTimeout(handle);
                var return_status = { event_status: code, tx_id: transaction_id_string };
                if (code !== 'VALID') {
                    console.error('The transaction was invalid, code = ' + code);
                    resolve(return_status);
                } else {
                    console.log('The transaction has been committed on peer ' + event_hub.getPeerAddr());
                    resolve(return_status);
                }
            }, (err) => {
                reject(new Error('There was a problem with the eventhub ::' + err));
            },
                { disconnect: true }
            );
            event_hub.connect();
        });
        promises.push(txPromise); return Promise.all(promises);
    } else {
        console.error('Failed to send Proposal or receive valid response. Response null or status is not 200. exiting...');
        throw new Error('Failed to send Proposal or receive valid response. Response null or status is not 200. exiting...');
    }
}).then((results) => {
    console.log('Send transaction promise and event listener promise have completed'); if (results && results[0] && results[0].status === 'SUCCESS') {
        console.log('Successfully sent transaction to the orderer.');
    } else {
        console.error('Failed to order the transaction. Error code: ' + results[0].status);
    } if (results && results[1] && results[1].event_status === 'VALID') {
        console.log('Successfully committed the change to the ledger by the peer');
    } else {
        console.log('Transaction failed to be committed to the ledger due to ::' + results[1].event_status);
    }
}).catch((err) => {
    console.error('Failed to invoke successfully :: ' + err);
});

本文由小韦云原创，转载请注明出处：https://www.bctos.cn/doc/4/1825，否则追究其法律责任

最后

以上就是勤恳大地为你收集整理的编写nodejs代码的全部内容，希望文章能够帮你解决编写nodejs代码所遇到的程序开发问题。

如果觉得靠谱客网站的内容还不错，欢迎将靠谱客网站推荐给程序员好友。