部署一个私链以太坊的智能合约

部署智能合约的步骤为：

1. 启动一个以太坊节点 (例如geth或者testrpc)。
2. 使用solc编译智能合约。 => 获得二进制代码。
3. 将编译好的合约部署到网络。（这一步会消耗以太币，还需要使用你的节点的默认地址或者指定地址来给合约签名。） => 获得合约的区块链地址和ABI（合约接口的JSON表示，包括变量，事件和可以调用的方法）。(译注：作者在这里把ABI与合约接口弄混了。ABI是合约接口的二进制表示。)
4. 用web3.js提供的JavaScript API来调用合约。

智能合约.png

Brew MacOS包管理器

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

安装go的环境

brew install go

安装 geth

npm install -g solc

Solidity以太坊智能合约语言

brew  install solidity

geth console会启动节点，geth attach是通过rpc或者ipc和已经启动的节点进行交互。所以二者的使用区别还是挺大的，在geth console里面可以使用所有模块的api，但是geth attach只能使用已经打开的模块的api，如果节点没有打开rpc geth attach甚至都不能连接上节点

1,启动一个以太坊节点

1,geth --datadir "./" --nodiscover console

2,user1 = eth.accounts[0]

"0xa4aa2105cc3e6b6a83faaaf72782d1e9a68e90ca"

> eth.getBalance(user1)

1.156e+21

> user2 = eth.accounts[1]

"0x33481f6d7b7f4ff430397913af1eaf582f3f4391"

> eth.getBalance(user2)

4000000000000000000

2,智能合约代码：

contract Multiply7 {
   event Print(uint);
   function multiply(uint input) returns (uint) {
      Print(input * 7);
      return input * 7;
   }
}

3，获得abiDefinition和bytecode,

通过https://remix.ethereum.org编译智能合约或者solc编译

合约1.png

合约2.png

我们先把合约代码压缩为一行．新建一个ssh session, 切换到geth用户环境su - geth, 然后输入：cat contracts/Token.sol | tr '\n' 空格'空格 '.

转义成字符串 http://www.bejson.com

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

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4，看黑板：字节码前加0x

bytecode="0x6060604052341561000f57600080fd5b60b18061001d6000396000f300606060405260043610603f576000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa1146044575b600080fd5b3415604e57600080fd5b606260048080359060200190919050506078565b6040518082815260200191505060405180910390f35b60006007820290509190505600a165627a7a72305820e8baa72a4bd1ffe2e8fa51812e8d65fc7b145baf48382c4ae5039510fd35a6ff0029"

5，通过abiDefinition和bytecode实例化创建合约

var contract = eth.contract(abi);

var initializer = {from:web3.eth.accounts[0],data:bytecode,gas:300000};
personal.unlockAccount(user1,"jianghua")

var token = contract.new(initializer)

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INFO [03-03|17:25:44] Submitted contract creation fullhash=0x7e1bd79681ee748b1057f123a9951652e67232c2624631a5531edb0bb629e88b contract=0x1BeEf17Dac85D369d41A9891276D58fC8F877A24

6，需要通过挖矿这一步骤，对合约地址进行确认

miner.start(4)

 admin.sleepBlocks(2)

      miner.stop()

到此为止，合约的布署已布署到了区块链上。

7，通过合约地址，实例化自己的合约，并进行调用

mycontract = contract.at(token.address)

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{ abi: [{ constant: false, inputs: [{...}], name: "multiply", outputs: [{...}], payable: false, stateMutability: "nonpayable", type: "function" }], address: "0x1beef17dac85d369d41a9891276d58fc8f877a24", transactionHash: null, allEvents: function(), multiply: function() }

8，到这里，合约的布署与调用完成

mycontract.multiply.call(2)

到了这一步，我们可以得到自己合约的返回值14

9，预估手续费

web3.eth.estimateGas({data:bytecode})

10，检查合约是否部署成功

eth.getCode("0x1beef17dac85d369d41a9891276d58fc8f877a24")

"0x606060405260043610603f576000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa1146044575b600080fd5b3415604e57600080fd5b606260048080359060200190919050506078565b6040518082815260200191505060405180910390f35b60006007820290509190505600a165627a7a72305820e8baa72a4bd1ffe2e8fa51812e8d65fc7b145baf48382c4ae5039510fd35a6ff0029"

11，验证区块的内容

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eth.getBlock(2550)

{ difficulty: 314416, extraData: "0xd783010802846765746886676f312e31308664617277696e", gasLimit: 4712388, gasUsed: 99930, hash: "0x57ca73b779ae13c542f0421fc81a272fc6ce938aab1951b412f8813b6dc5bc8e", logsBloom: "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000", miner: "0xa4aa2105cc3e6b6a83faaaf72782d1e9a68e90ca", mixHash: "0xecee4f13a617954c9bfe19e14bdf00c6b0d006d16e19e7474faa8de49eb74bf9", nonce: "0x39f04fd757c3fab6", number: 2550, parentHash: "0xcdfb7e8f78f86e942acfe5a9a1f1ef3637a77cd96ebf35f28e6880e40e94fa0c", receiptsRoot: "0xea304d377e8d7db719679ecfb3900e0b6c18469512ac3ba1c74c754e54f73d9e", sha3Uncles: "0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347", size: 830, stateRoot: "0x69c10e0e14757623f279f8df6564659f1ac4cf25ab2ec559acedb964315804f7", timestamp: 1520069708, totalDifficulty: 589085710, transactions: ["0x7e1bd79681ee748b1057f123a9951652e67232c2624631a5531edb0bb629e88b"], transactionsRoot: "0xba26a1e628172e65320c9d9474148763c03bd16513fc63b425f781537d542aa9", uncles: [] }

12，验证交易信息

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eth.getTransaction("0x7e1bd79681ee748b1057f123a9951652e67232c2624631a5531edb0bb629e88b")

{ blockHash: "0x57ca73b779ae13c542f0421fc81a272fc6ce938aab1951b412f8813b6dc5bc8e", blockNumber: 2550, from: "0xa4aa2105cc3e6b6a83faaaf72782d1e9a68e90ca", gas: 300000, gasPrice: 0, hash: "0x7e1bd79681ee748b1057f123a9951652e67232c2624631a5531edb0bb629e88b", input: "0x6060604052341561000f57600080fd5b60b18061001d6000396000f300606060405260043610603f576000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa1146044575b600080fd5b3415604e57600080fd5b606260048080359060200190919050506078565b6040518082815260200191505060405180910390f35b60006007820290509190505600a165627a7a72305820e8baa72a4bd1ffe2e8fa51812e8d65fc7b145baf48382c4ae5039510fd35a6ff0029", nonce: 4, r: "0x4a3d67e18204891de590b634ef34cdff373a199f0640fa5d11b91b4788ad8290", s: "0x45467daa1b578c05e5b2c64b564a41a306d7e1ecc21ce1b472290b719fecc77c", to: null, transactionIndex: 0, v: "0xfe7", value: 0 }

合约的布署与调用验证无误，大功告成！