以太坊私网建立、合约编译、部署

一、为什么用到私有链？

在以太坊的共有链上部署智能合约、发起交易需要花费以太币。而通过修改配置，可以在本机搭建一套以太坊私有链，因为与公有链没关系，既不用同步公有链庞大的数据，也不用花钱购买以太币，很好地满足了智能合约开发和测试的要求，开发好的智能合约也可以很容易地切换接口部署到以太坊公有链上。

二、开源工具和语言

1、brewMacOS包管理器

拷贝下面的命令到终端，然后回车。

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

2、install Go compiler

liyuechun:Downloads yuechunli$ brew install go

3、geth运行以太坊节点

下载Source code (tar.gz)

liyuechun:Downloads yuechunli$ cd go-ethereum-1.5.9
liyuechun:go-ethereum-1.5.9 yuechunli$ pwd
/Users/liyuechun/Downloads/go-ethereum-1.5.9
liyuechun:go-ethereum-1.5.9 yuechunli$ make geth

4、Solidity以太坊智能合约语言

brew update
brew upgrade
brew tap ethereum/ethereum
brew install solidity
brew linkapps solidity

备注：安装时间可能有点长，请耐心等待...
备注：安装时间可能有点长，请耐心等待...
备注：安装时间可能有点长，请耐心等待...

如果碰见下面的错误，请移步：http://blog.csdn.net/Sico2Sico/article/details/71082130

The GitHub credentials in the macOS keychain may be invalid.
Clear them with:
  printf "protocol=https
host=github.com
" | git credential-osxkeychain erase
Or create a personal access token:
  https://github.com/settings/tokens/new?scopes=gist,public_repo&description=Homebrew

三、建立私链

1. 创建一个文件夹来存储你的私链数据

liyuechun:1015 yuechunli$ mkdir privatechain
liyuechun:1015 yuechunli$ pwd
/Users/liyuechun/Desktop/1015
liyuechun:1015 yuechunli$ ls
privatechain
liyuechun:1015 yuechunli$

2. 使用`geth`来加载

geth --networkid 123 --dev --datadir data1 --rpc --rpcaddr 192.168.1.5 --rpcport 8989 --port 3000

各选项含义如下：

--identity：指定节点 ID；
--rpc：表示开启 HTTP-RPC 服务；
--rpcaddr：HTTP-RPC 服务ip地址；
--rpcport：指定 HTTP-RPC 服务监听端口号（默认为 8545）；
--datadir：指定区块链数据的存储位置；
--port：指定和其他节点连接所用的端口号（默认为 30303）；
--nodiscover：关闭节点发现机制，防止加入有同样初始配置的陌生节点。

执行上面的命令，你应该能看到下面的信息：

INFO [10-15|03:14:50] IPC endpoint opened: /Users/liyuechun/Desktop/1015/privchain/geth.ipc
INFO [10-15|03:14:50] HTTP endpoint opened: http://127.0.0.1:8545

如果你切换到privchain文件夹里面，你会看到geth, geth.ipc, 和 keystore。

liyuechun:1015 yuechunli$ cd data1/
liyuechun:data1 yuechunli$ ls
geth        geth.ipc    keystore
liyuechun:data1 yuechunli$

保持节点的运行，不要关闭终端，重新打开一个终端，使用geth attach连接节点，并且打开geth console

liyuechun:privchain yuechunli$ geth attach ipc:/Users/liyuechun/Desktop/1015/privchain/geth.ipc 
Welcome to the Geth JavaScript console!

instance: Geth/v1.7.1-stable-05101641/darwin-amd64/go1.9.1
 modules: admin:1.0 debug:1.0 eth:1.0 miner:1.0 net:1.0 personal:1.0 rpc:1.0 shh:1.0 txpool:1.0 web3:1.0

>

这是一个交互式的 JavaScript 执行环境，在这里面可以执行 JavaScript 代码，其中 > 是命令提示符。在这个环境里也内置了一些用来操作以太坊的 JavaScript 对象，可以直接使用这些对象。这些对象主要包括：

eth：包含一些跟操作区块链相关的方法；
net：包含一些查看p2p网络状态的方法；
admin：包含一些与管理节点相关的方法；
miner：包含启动&停止挖矿的一些方法；
personal：主要包含一些管理账户的方法；
txpool：包含一些查看交易内存池的方法；
web3：包含了以上对象，还包含一些单位换算的方法。

3. 相关api命令

查看账户

> personal.listAccounts
[]
>

创建账户

> personal.newAccount('liyuechun') 
"0xb6d7d842e7dc9016fa6900a183b2be26fc90b2d8"
>

PS：里面的liyuechun是你账户的密码，输入你自己喜欢的密码。

查看账户

> personal.listAccounts 
["0xb6d7d842e7dc9016fa6900a183b2be26fc90b2d8"]
>

4. web3命令

https://ethereumbuilders.gitbooks.io/guide/content/en/ethereum_javascript_api.html

> web3.eth.coinbase 
"0xb6d7d842e7dc9016fa6900a183b2be26fc90b2d8"
>

5. 编写智能合约代码

pragma solidity ^0.4.18;

contract test { 
    
    function multiply(uint a) returns(uint d){
        
        return a * 7;
    }
    
}

6. 获取智能合约字节码和abi

代码拷贝到https://remix.ethereum.org，编译，然后拷贝字节码和ABI。

字节码

6060604052341561000f57600080fd5b5b60ab8061001e6000396000f30060606040526000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa114603d575b600080fd5b3415604757600080fd5b605b60048080359060200190919050506071565b6040518082815260200191505060405180910390f35b60006007820290505b9190505600a165627a7a7230582067d7c851e14e862886b6f53dad6825135557fb3a4b691350c94ea5b80605f6770029

[
  {
    "constant": true,
    "inputs": [
      {
        "name": "a",
        "type": "uint256"
      }
    ],
    "name": "multiply",
    "outputs": [
      {
        "name": "d",
        "type": "uint256"
      }
    ],
    "payable": false,
    "type": "function",
    "stateMutability": "view"
  }
]

7. 在bejson中转义成字符串

http://www.bejson.com

[{"constant":true,"inputs":[{"name":"a","type":"uint256"}],"name":"multiply","outputs":[{"name":"d","type":"uint256"}],"payable":false,"type":"function","stateMutability":"view"}]

7. 通过abi创建合约对象

> var abi = JSON.parse('[{"constant":true,"inputs":[{"name":"a","type":"uint256"}],"name":"multiply","outputs":[{"name":"d","type":"uint256"}],"payable":false,"type":"function","stateMutability":"view"}]')
> myContract = web3.eth.contract(abi)
{
  abi: [{
      constant: false,
      inputs: [{...}],
      name: "multiply",
      outputs: [{...}],
      payable: false,
      type: "function"
  }],
  eth: {
    accounts: ["0x2abf46d8b0d940cdeedd55872bc0648add40227d"],
    blockNumber: 384,
    coinbase: "0x2abf46d8b0d940cdeedd55872bc0648add40227d",
    compile: {
      lll: function(),
      serpent: function(),
      solidity: function()
    },
    defaultAccount: undefined,
    defaultBlock: "latest",
    gasPrice: 0,
    hashrate: 0,
    mining: false,
    pendingTransactions: [],
    protocolVersion: "0x3f",
    syncing: false,
    call: function(),
    contract: function(abi),
    estimateGas: function(),
    filter: function(fil, callback),
    getAccounts: function(callback),
    getBalance: function(),
    getBlock: function(),
    getBlockNumber: function(callback),
    getBlockTransactionCount: function(),
    getBlockUncleCount: function(),
    getCode: function(),
    getCoinbase: function(callback),
    getCompilers: function(),
    getGasPrice: function(callback),
    getHashrate: function(callback),
    getMining: function(callback),
    getPendingTransactions: function(callback),
    getProtocolVersion: function(callback),
    getRawTransaction: function(),
    getRawTransactionFromBlock: function(),
    getStorageAt: function(),
    getSyncing: function(callback),
    getTransaction: function(),
    getTransactionCount: function(),
    getTransactionFromBlock: function(),
    getTransactionReceipt: function(),
    getUncle: function(),
    getWork: function(),
    iban: function(iban),
    icapNamereg: function(),
    isSyncing: function(callback),
    namereg: function(),
    resend: function(),
    sendIBANTransaction: function(),
    sendRawTransaction: function(),
    sendTransaction: function(),
    sign: function(),
    signTransaction: function(),
    submitTransaction: function(),
    submitWork: function()
  },
  at: function(address, callback),
  getData: function(),
  new: function()
}

8. 检查coinbase账号余额

> account1 = web3.eth.coinbase
"0x2abf46d8b0d940cdeedd55872bc0648add40227d"
> web3.eth.getBalance(account1)
0
>

如果余额大于0，继续，否则，开始挖矿。

> miner.start();
null
>

挖矿过程中，切换到节点终端，你会发现一直在挖矿。

挖矿

如果你觉得差不多了，可以运行下面的命令停止挖矿。

miner.stop();

9. 停止挖矿，并且查余额

> miner.start();
null
> miner.stop();
true
> web3.eth.getBalance(account1)
1.152e+21
>

10. 解锁coinbase账号，我们通过coinbase账号来付费部署合约

liyuechun: 换成你的密码。

> personal.unlockAccount(account1, 'liyuechun') 
true
>

11. 预估手续费

> bytecode = "6060604052341561000f57600080fd5b5b60ab8061001e6000396000f30060606040526000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa114603d575b600080fd5b3415604757600080fd5b605b60048080359060200190919050506071565b6040518082815260200191505060405180910390f35b60006007820290505b9190505600a165627a7a7230582067d7c851e14e862886b6f53dad6825135557fb3a4b691350c94ea5b80605f6770029"
"6060604052341561000f57600080fd5b5b60ab8061001e6000396000f30060606040526000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa114603d575b600080fd5b3415604757600080fd5b605b60048080359060200190919050506071565b6040518082815260200191505060405180910390f35b60006007820290505b9190505600a165627a7a7230582067d7c851e14e862886b6f53dad6825135557fb3a4b691350c94ea5b80605f6770029"
> web3.eth.estimateGas({data: bytecode})
Error: invalid argument 0: json: cannot unmarshal hex string without 0x prefix into Go struct field CallArgs.data of type hexutil.Bytes
    at web3.js:3104:20
    at web3.js:6191:15
    at web3.js:5004:36
    at <anonymous>:1:1

> bytecode = "0x6060604052341561000f57600080fd5b5b60ab8061001e6000396000f30060606040526000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa114603d575b600080fd5b3415604757600080fd5b605b60048080359060200190919050506071565b6040518082815260200191505060405180910390f35b60006007820290505b9190505600a165627a7a7230582067d7c851e14e862886b6f53dad6825135557fb3a4b691350c94ea5b80605f6770029"
"0x6060604052341561000f57600080fd5b5b60ab8061001e6000396000f30060606040526000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa114603d575b600080fd5b3415604757600080fd5b605b60048080359060200190919050506071565b6040518082815260200191505060405180910390f35b60006007820290505b9190505600a165627a7a7230582067d7c851e14e862886b6f53dad6825135557fb3a4b691350c94ea5b80605f6770029"
> web3.eth.estimateGas({data: bytecode})
98391
>

备注：字节码前面需要添加0x。手续费大概为98391``gas。

12. 部署合约，为了方便理解，设置一个回调函数

> contractInstance = contract.new({data: bytecode, gas: 1000000, from: account1}, function(e, contract){
  if(!e){
    if(!contract.address){
      console.log("Contract transaction send: Transaction Hash: "+contract.transactionHash+" waiting to be mined...");
    }else{
      console.log("Contract mined! Address: "+contract.address);
      console.log(contract);
    }
  }else{
    console.log(e)
  }
})
Contract transaction send: Transaction Hash: 0x5e2aebbf400d71a32e807dc3f11f1053b6ee3b2a81435ed8ace2fa54eebb9f3d waiting to be mined...
{
  abi: [{
      constant: false,
      inputs: [{...}],
      name: "multiply",
      outputs: [{...}],
      payable: false,
      type: "function"
  }],
  address: undefined,
  transactionHash: "0x5e2aebbf400d71a32e807dc3f11f1053b6ee3b2a81435ed8ace2fa54eebb9f3d"
}
>

13. 你的合约等待挖矿，开始挖矿，等一会儿，停止

> miner.start()
null
> Contract mined! Address: 0xbf8b24283f2516360d3a4ba1db0df78ae74689db
[object Object]
> miner.stop()
true
>

image

14. 检查合约是否部署成功

> eth.getCode(contractInstance.address)
"0x60606040526000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa114603d575b600080fd5b3415604757600080fd5b605b60048080359060200190919050506071565b6040518082815260200191505060405180910390f35b60006007820290505b9190505600a165627a7a7230582067d7c851e14e862886b6f53dad6825135557fb3a4b691350c94ea5b80605f6770029"
>

15. 调用合约方法

> contractInstance.multiply(6)
42
>

PS：这里添加call的原因是因为multiply函数没有添加constant。

pragma solidity ^0.4.4;

contract test {

    function multiply(uint a) returns(uint d){

        return a * 7;
    }

}

Over Game!!!!