Question

21.4. 查询操作

		
[root@localhost token]# cat queryToken.js 
'use strict';

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

//
var fabric_client = new Fabric_Client();

// setup the fabric network
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: 'token3',
		fcn: 'showAccount',
		args: ['coinbase']
	};

	// send the query proposal to the peer
	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);
});		
		
		

核心代码

		
	const request = {
		chaincodeId: 'token3',	// 链码名称	
		fcn: 'showAccount',	//调用方法
		args: ['coinbase']	// 传递参数
	};
		
		

运行结果

			
[root@localhost token]# node queryToken.js 
Store path:/root/fabric-samples/fabcar/hfc-key-store
Successfully loaded user1 from persistence
Query has completed, checking results
Response is  {"BalanceOf":{},"Frozen":false,"Name":"coinbase"}