web3 部署合约

web3 部署合约

代码：

let Web3 = require('web3');
let web3;

if (typeof web3 !== 'undefined') {
    web3 = new Web3(web3.currentProvider);
} else {
    // set the provider you want from Web3.providers
    web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));
}

let from = web3.eth.accounts[0];

//编译合约
let transferCompiled = [
	{
		"constant": false,
		"inputs": [],
		"name": "deposit",
		"outputs": [],
		"payable": true,
		"type": "function",
		"stateMutability": "payable"
	},
	{
		"anonymous": false,
		"inputs": [
			{
				"indexed": true,
				"name": "_from",
				"type": "address"
			},
			{
				"indexed": true,
				"name": "_to",
				"type": "address"
			},
			{
				"indexed": true,
				"name": "value",
				"type": "uint256"
			}
		],
		"name": "transfer",
		"type": "event"
	},
	{
		"payable": false,
		"type": "fallback",
		"stateMutability": "nonpayable"
	},
	{
		"constant": true,
		"inputs": [],
		"name": "getBanlance",
		"outputs": [
			{
				"name": "",
				"type": "uint256"
			}
		],
		"payable": false,
		"type": "function",
		"stateMutability": "view"
	}
]

//得到合约对象
//let abiDefinition = transferCompiled["info"]["abiDefinition"];
let transferContract = web3.eth.contract(transferCompiled);

//2. 部署合约

//2.1 获取合约的代码，部署时传递的就是合约编译后的二进制码
let deployCode = "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";

//2.2 部署者的地址，当前取默认账户的第一个地址。
let deployeAddr = web3.eth.accounts[0];
console.log(deployeAddr);
//2.3 异步方式，部署合约
//警告，你不应该每次都部署合约，这里只是为了提供一个可以完全跑通的例子！！！
transferContract.new({
    data: deployCode,
    from: deployeAddr,
    gas: 1000000
}, function(err, myContract) {
    if (!err) {
        // 注意：这个回调会触发两次
        //一次是合约的交易哈希属性完成
        //另一次是在某个地址上完成部署

        // 通过判断是否有地址，来确认是第一次调用，还是第二次调用。
        if (!myContract.address) {
            console.log("contract deploy transaction hash: " + myContract.transactionHash) //部署合约的交易哈希值

            // 合约发布成功后，才能调用后续的方法
        } else {
            console.log("contract deploy address: " + myContract.address) // 合约的部署地址

            console.log("Current balance: " + myContract.getBanlance());

            var event = myContract.transfer();

            // 监听
            event.watch(function(error, result){
              console.log("Event are as following:-------");

              for(let key in result){ 
                console.log(key + " : " + result[key]);
              }

              console.log("Event ending-------");
            });

            //使用transaction方式调用，写入到区块链上
            myContract.deposit.sendTransaction({
                from: deployeAddr,
                value: 100,
                gas: 1000000
            }, function(err, result){
              console.log("Deposit status: " + err + " result: " + result);
              console.log("After deposit balance: " + myContract.getBanlance());

              //终止监听，注意这里要在回调里面，因为是异步执行的。
              event.stopWatching();
            });
        }
    }
    else
    	console.log(err);
});

结果：

此处的code 是手动到命令行上编译生成的，web3的编译语句不能用

部署完成后，在私有链上调用代码操作可查看在geth客户端调用已部署的智能合约

调用过程如下：

1）获取合约地址：

合约地址即为上图的 contract deploy address

2）获取abi：abi在remix复制

3）获取合约

4）调用

此处的getBalance只是获取状态，因此不需要消耗gas：

这次调用的是deposite函数，因为会导致区块链的数据发送改变，所以需要使用sendTransaction：

结果如下：调用了四次，但因为出块需要时间，而call不需要对区块进行改写，执行时间很短，所以此时getBalance（）得到的是上一次交易后的结果

最终结果为 500：

若想实时获得交易结果，需要使用 solidity 的 event。event 可以实现web3 js与交易执行同步，交易一完成，web3即可获得交易结果。

solidity 源码为：

pragma solidity ^0.4.0;
contract Transfer{  
    event transfer(address indexed _from, address indexed _to, uint indexed value); 
    function deposit() payable {    
        address current = this;   
    	uint value = msg.value;   
    
    transfer(msg.sender, current, value);  
        current.transfer(10);
    }  
    function getBanlance() constant returns(uint) 
    {     
        return this.balance; 
    } 
    /* fallback function */  
    function(){}
    
}

部署完后的调用代码（diaoyong.js）

//部署完后的调用代码
let Web3 = require('web3');
let web3;

if (typeof web3 !== 'undefined') {
    web3 = new Web3(web3.currentProvider);
} else {
    // set the provider you want from Web3.providers
    web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));
}
console.log("good");

//abi，直接在remix 里面复制
var abi = [{"constant": false,"inputs": [],"name": "deposit","outputs": [],"payable": true,"type": "function","stateMutability": "payable"},{"constant": true,"inputs": [],"name": "getBanlance","outputs": [{"name": "","type": "uint256"}],"payable": false,"type": "function","stateMutability": "view"},{"payable": false,"type": "fallback","stateMutability": "nonpayable"},{"anonymous": false,"inputs": [{"indexed": true,"name": "_from","type": "address"},{"indexed": true,"name": "_to","type": "address"},{"indexed": true,"name": "value","type": "uint256"}],"name": "transfer","type": "event"}];

//合约地址
var address = web3.eth.accounts[0];
var metacoin = web3.eth.contract(abi).at(address);
var t = metacoin.getBanlance.call();
console.log(t['c']);
let a = web3.eth.accounts[0];
metacoin.deposit.sendTransaction({from:a,value:100,gas:100000
},function(err,result){
	console.log(err + "result :" + result);
});
console.log(metacoin.getBanlance.call());