以太坊智能合约部署与交互

笔阁

发布于 2018-09-04 17:41:32

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发布于 2018-09-04 17:41:32

文章被收录于专栏：极客编程

启动容器来执行geth命令

root@ubu-blockchain2:~# docker run -i blockchain101/ethereum-geth:1.6.5 geth attach http://45.32.252.88:8201
Welcome to the Geth JavaScript console!

instance: Geth/01/v1.6.5-stable/linux-amd64/go1.8
coinbase: 0x4c57e7e9c2f728046ddc6e96052056a241bdbd0a
at block: 6064 (Wed, 02 Aug 2017 01:13:50 UTC)
 datadir: /ethcluster/779977/data/01
 modules: admin:1.0 eth:1.0 net:1.0 rpc:1.0 web3:1.0

查看我们的账户和余额

eth.getBalance(eth.accounts[0])

11000000000000000000
eth.getBalance(eth.accounts[1])
0
eth.accounts[0]
"0x4c57e7e9c2f728046ddc6e96052056a241bdbd0a"
> eth.accounts[1]
"0xe82e2f0a5abd8774767b9751659976f9c4f59181"

发起一笔交易

eth.sendTransaction({from:eth.accounts[0],to:eth.accounts[1],value:web3.toWei(3,'ether')})

"0x0075da712d26aea17d6647035107f509e13eaf3d113c1577db14d4cc4216caec"

查看交易细节

>  eth.getTransaction("0x0075da712d26aea17d6647035107f509e13eaf3d113c1577db14d4cc4216caec")

{
  blockHash: "0x3115703894dc6015c96ef4de3e5615f416498ca1f985902b38cd70e27dab8871", blockNumber: 1250, from: "0x4c57e7e9c2f728046ddc6e96052056a241bdbd0a", gas: 90000, gasPrice: 18000000000, hash: "0x0075da712d26aea17d6647035107f509e13eaf3d113c1577db14d4cc4216caec", input: "0x", nonce: 0, r: "0x2aef2c1fa03a0fa4172d21e3383d8c0431d45ec855b9d16efdd5eb2de90c414c", s: "0xc4d530fb7902bf509fe56bfbea4861bf6cc16791afc9c9103c1a18f77407d1f", to: "0xe82e2f0a5abd8774767b9751659976f9c4f59181", transactionIndex: 0, v: "0x17cdb6", value: 3000000000000000000 }
> eth.getBalance(eth.accounts[1])

3000000000000000000

验证用户0的余额

> eth.getBalance(eth.accounts[0])

7999622000000000000

编写一个简单的合约

contract Sample {
    uint public value;

          function Sample(uint v){
                    value=v;
          }

          function set(uint v){
                    value=v;
          }

          function get() constant returns (uint){
                    return value;
          }
}

在remix网页编译得到ABI接口和合约的二进制代码、

 abi=[{"constant":true,"inputs":[],"name":"value","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"v","type":"uint256"}],"name":"set","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"get","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"inputs":[{"name":"v","type":"uint256"}],"payable":false,"type":"constructor"}]



[{
    constant: true,
    inputs: [],
    name: "value",
    outputs: [{
        name: "",
        type: "uint256"
    }],
    payable: false,
    type: "function"
}, {
    constant: false,
    inputs: [{
        name: "v",
        type: "uint256"
    }],
    name: "set",
    outputs: [],
    payable: false,
    type: "function"
}, {
    constant: true,
    inputs: [],
    name: "get",
    outputs: [{
        name: "",
        type: "uint256"
    }],
    payable: false,
    type: "function"
}, {
    inputs: [{
        name: "v",
        type: "uint256"
    }],
    payable: false,
    type: "constructor"
}]

需要使用eth.contract来定义一个合约类

> sample=eth.contract(abi)

{
  abi: [{
      constant: true,
      inputs: [],
      name: "value",
      outputs: [{...}],
      payable: false,
      type: "function"
  }, {
      constant: false,
      inputs: [{...}],
      name: "set",
      outputs: [],
      payable: false,
      type: "function"
  }, {
      constant: true,
      inputs: [],
      name: "get",
      outputs: [{...}],
      payable: false,
      type: "function"
  }, {
      inputs: [{...}],
      payable: false,
      type: "constructor"
  }],
  eth: {
    accounts: ["0x4c57e7e9c2f728046ddc6e96052056a241bdbd0a", "0xe82e2f0a5abd8774767b9751659976f9c4f59181"],
    blockNumber: 6225,
    coinbase: "0x4c57e7e9c2f728046ddc6e96052056a241bdbd0a",
    compile: {
      lll: function(),
      serpent: function(),
      solidity: function()
    },
    defaultAccount: undefined,
    defaultBlock: "latest",
    gasPrice: 18000000000,
    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()
}

合约的二进制代码赋值给SampleHEX方便使用

SampleHEX="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"

把合约代码部署上链

> thesample=sample.new(1,{from:eth.accounts[0],data:SampleHEX,gas:3000000})

{
  abi: [{
      constant: true,
      inputs: [],
      name: "value",
      outputs: [{...}],
      payable: false,
      type: "function"
  }, {
      constant: false,
      inputs: [{...}],
      name: "set",
      outputs: [],
      payable: false,
      type: "function"
  }, {
      constant: true,
      inputs: [],
      name: "get",
      outputs: [{...}],
      payable: false,
      type: "function"
  }, {
      inputs: [{...}],
      payable: false,
      type: "constructor"
  }],
  address: undefined,
  transactionHash: "0xee74bcb4461c9712ec9aca96a5a3a4c3c64be1213854d519fc8e5432b554f7a1"
}

查看交易细节

> samplerecpt=eth.getTransactionReceipt("0xee74bcb4461c9712ec9aca96a5a3a4c3c64be1213854d519fc8e5432b554f7a1")

{
  blockHash: "0xddba16545af882835fb9a69a0e5f3b9287c61664837d5ea0068b38575cb665c5",
  blockNumber: 6246,
  contractAddress: "0x7504fa9d64ab290844b82660d43b310f8fba0276",
  cumulativeGasUsed: 141836,
  from: "0x4c57e7e9c2f728046ddc6e96052056a241bdbd0a",
  gasUsed: 141836,
  logs: [],
  logsBloom: "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
  root: "0xd1093ecaca9cc0d10e82a533a15feccedf7ff5c79fb3ebd9366ec0b35dbef478",
  to: null,
  transactionHash: "0xee74bcb4461c9712ec9aca96a5a3a4c3c64be1213854d519fc8e5432b554f7a1",
  transactionIndex: 0
}

合约命名

> samplecontract=sample.at("0x7504fa9d64ab290844b82660d43b310f8fba0276")

{
  abi: [{
      constant: true,
      inputs: [],
      name: "value",
      outputs: [{...}],
      payable: false,
      type: "function"
  }, {
      constant: false,
      inputs: [{...}],
      name: "set",
      outputs: [],
      payable: false,
      type: "function"
  }, {
      constant: true,
      inputs: [],
      name: "get",
      outputs: [{...}],
      payable: false,
      type: "function"
  }, {
      inputs: [{...}],
      payable: false,
      type: "constructor"
  }],
  address: "0x7504fa9d64ab290844b82660d43b310f8fba0276",
  transactionHash: null,
  allEvents: function(),
  get: function(),
  set: function(),
  value: function()
}

合约查看功能函数get（）,然后调用set()函数，再get()查看时已经改变了

samplecontract.get.call()
1

> samplecontract.set.sendTransaction(9, {from:eth.accounts[0], gas:3000000})

"0x822ee6fb4caceb7e844c533f7f3bc57806f7cb3676fb3066eb848cca46b2f38a"

> samplecontract.get.call()

9

我们再打开一个终端，打开cluster1的peer02的控制台，直接at到上一个终端部署的智能合约地址并进行set操作

root@ubu-blockchain2:~/ethereum-docker/ethereum-docker/ethereum-testnet-docker/dockercomposefiles# docker run -i blockchain101/ethereum-geth:1.6.5 geth attach http://45.32.252.88:9201
Welcome to the Geth JavaScript console!


>  abi=[{"constant":true,"inputs":[],"name":"value","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"v","type":"uint256"}],"name":"set","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"get","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"inputs":[{"name":"v","type":"uint256"}],"payable":false,"type":"constructor"}]


> sample=eth.contract(abi)

SampleHEX="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"

直接把合约地址赋值并进行set操作

samplecontract=sample.at("0x7504fa9d64ab290844b82660d43b310f8fba0276")

> samplecontract.get.call()

9

简单的方法来了。智能合约的部署需要编译，这里用在线编译： https://ethereum.github.io/browser-solidity/#version=soljson-v0.4.14+commit.c2215d46.js 修改编译好的abi和对象名称：

这里在网上找了个代币的只能合约，可以进行充值、转账和查询，issue 函数可以向充值以太到合约账户，transfer 函数可以向其他账号发送token，getBalance 函数可以获取某个账号的token余额，代码如下：
pragma solidity ^0.4.2;
contract Token {
             address issuer;
             mapping (address => uint) balances;

             event Issue(address account, uint amount);
             event Transfer(address from, address to,uint amount);

             function Token() {
                 issuer = msg.sender;
             }

             function issue(address account, uintamount) {
                 if (msg.sender != issuer) throw;
                 balances[account] += amount;
             }

             function transfer(address to, uint amount){
                 if (balances[msg.sender] < amount)throw;

                 balances[msg.sender] -= amount;
                 balances[to] += amount;

                 Transfer(msg.sender, to, amount);
             }

             function getBalance(address account)constant returns (uint) {
                 return balances[account];
             }
         }

修改编译好的gas和对象名称：
varbrowser_untitled_sol_tokenContract =web3.eth.contract([{"constant":false,"inputs":[{"name":"account","type":"address"},{"name":"amount","type":"uint256"}],"name":"issue","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"to","type":"address"},{"name":"amount","type":"uint256"}],"name":"transfer","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"account","type":"address"}],"name":"getBalance","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"inputs":[],"payable":false,"type":"constructor"},{"anonymous":false,"inputs":[{"indexed":false,"name":"account","type":"address"},{"indexed":false,"name":"amount","type":"uint256"}],"name":"Issue","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"name":"from","type":"address"},{"indexed":false,"name":"to","type":"address"},{"indexed":false,"name":"amount","type":"uint256"}],"name":"Transfer","type":"event"}]);
var token =browser_untitled_sol_tokenContract.new(
   {
     from: web3.eth.accounts[0],
     data:'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',
     gas: '4300000'
   }, function (e, contract){
    console.log(e, contract);
    if (typeof contract.address !=='undefined') {
         console.log('Contract mined! address:' + contract.address + ' transactionHash: ' + contract.transactionHash);
    }
 })

此时输入合约部署的实例a_demotypes, 可以看到a_demotypes的详情。

控制台调用

> a_demotypes
{
  abi: [{
      constant: false,
      inputs: [{...}],
      name: "f",
      outputs: [{...}],
      payable: false,
      type: "function"
  }],
  address: "0x54ed7a5f5a63ddada3bfe83b3e632adabaa5fc2f",
  transactionHash: "0x69cde62bcd6458e14f40497f4840f422911d63f5dea2b3a9833e6810db64a1c9",
  allEvents: function(),
  f: function()
}

这里重点就是address表示的是合约的地址，你会发现这个和账号的信息结果一样，其实你也可以把这个合约地址看做是一个账号地址，后面我们外部调用到的就是这个合约地址。

充值
token.issue.sendTransaction(eth.accounts[0],100, {from: eth.accounts[0]});

发送 token
token.transfer(eth.accounts[1], 30, {from:eth.accounts[0]})

查看余额
token.getBalance()
控制台调用就不多说，和Java对象调用一样，直接调用即可

外部接口与智能合约交互 以太坊对外提供的有很多接口JSON RPC接口，web3接口，这里我们用JSON RPC接口。相关API: https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_sendrawtransaction 合约交互的原理 合约的交互都是一次交易，而我们要做的就是把要调用的方法和参数按照api规定的以参数的形式向区块请求一次交易，ethereum接收到我们的请求后通过解析传递的参数来执行相关的合约代码。 RPC接口给我们提供了俩个方法：eth_sendTransaction和eth_call。

eth_sendTransaction
Createsnew message call transaction or a contract creation, if the data field containscode.
Parameters

Object - The transaction object
from: DATA, 20 Bytes - The address the transaction is send from.
to: DATA, 20 Bytes - (optional when creating new contract) The address the transaction is directed to.
gas: QUANTITY - (optional, default: 90000) Integer of the gas provided for the transaction execution. It will return unused gas.
gasPrice: QUANTITY - (optional, default: To-Be-Determined) Integer of the gasPrice used for each paid gas
value: QUANTITY - (optional) Integer of the value send with this transaction
data: DATA - The compiled code of a contract OR the hash of the invoked method signature and encoded parameters. For details see Ethereum Contract ABI
nonce: QUANTITY - (optional) Integer of a nonce. This allows to overwrite your own pending transactions that use the same nonce.

可以看到，如果我们创建的为合约时，我们只需要from,to(文档上写的是可选的，但是实际操作中没有to为null的话合约不能正常执行，建议还是加上，这个值就是前面我们部署合约后生成的合约address),data。Data的属性的值具体可以看Contract ABI。这里大概说下： Data的值相对来说不是固定的，具体怎么生成与合约的参数类型，参数数量都有关联。这里我们以部署的token合约的三个方法为例：

充值issue (address account, uint amount) 这个方法有俩个参数，address充值账号，uint充值数量。根据Contract ABI，data值应该为方法名的sha3的前8个字节+参数的64字节，不够前面补充为0。这里方法名并不是issue (address account, uint amount)而是issue(address,uint256)的sha3值。

web3.sha3("issue(address,uint256)")
"0x867904b44b606800f6f10498e11292d04ea19bfc7fe4bc0f1695aa516381f73d"

我们往第一个账号充值10，这里的数据不是以太币，而是我们自己创建的代币。

 eth.accounts[0]
"0x0cc9684af605bae10de801218321c1336bb62946"

将10转换为16进制为

000000000000000000000000000000000000000000000000000000000000000a

那么data的数据为：

0x867904b4000000000000000000000000fdf57e81872562a6112656f961944ce821fdf7eb000000000000000000000000000000000000000000000000000000000000000a

那么最后我们调用eth_sendTransaction方法传递参数JSON对象为：

{
    from:0xfdf57e81872562a6112656f961944ce821fdf7eb, to:0x7fe133950fc010ce41322d88f64f1918b9abb3a3, data: 0x867904b4000000000000000000000000fdf57e81872562a6112656f961944ce821fdf7eb000000000000000000000000000000000000000000000000000000000000000a }

返回：此交易的hash值,此时该交易还没有执行，只是创建，还需要矿工通过挖矿才能完成。调用接口方法：

JsonRpcHttpClient client = newJsonRpcHttpClient(new URL(“http://127.0.0.1:8545”));
Object result = client.invoke(methodName,params, Object.class);

通过控制台查看第一个账号已有代币：

token.getbalance(eth.accounts[0])

执行调用接口代码。返回交易hash值：

0x2013764d1c3fea680f9015353497aa5f9f8d61580a3bd0524b3613b34329c095

此时控制台输入：

交易和充值一样，需要注意的是代币转出账号为from属性的值，代币转入账号为data属性里的值，to对应的是合约地址。 eth_call

Executes anew message call immediately without creating a transaction on the block chain.
Parameters

Object - The transaction call object
from: DATA, 20 Bytes - (optional) The address the transaction is sent from.
to: DATA, 20 Bytes - The address the transaction is directed to.
gas: QUANTITY - (optional) Integer of the gas provided for the transaction execution. eth_call consumes zero gas, but this parameter may be needed by some executions.
gasPrice: QUANTITY - (optional) Integer of the gasPrice used for each paid gas
value: QUANTITY - (optional) Integer of the value send with this transaction
data: DATA - (optional) Hash of the method signature and encoded parameters. For details seeEthereum Contract ABI
QUANTITY|TAG - integer block number, or the string "latest", "earliest" or "pending", see the default block parameter

这个方法返回一条信息给我们，相当于数据库的查询功能，参数也是三个，from,to,data，数据格式都是一样的。查询getBalance(address account) 查询方法hash码：

 web3.sha3("getBalance(address)")
"0xf8b2cb4f3943230388faeee074f1503714bff212640051caba01411868d14ae3"

查询我们上一步充值的账号，那么传递的参数data为：

0xf8b2cb4f000000000000000000000000fdf57e81872562a6112656f961944ce821fdf7eb

eth_call方法最后参数为：

{
       from: 0xfdf57e81872562a6112656f961944ce821fdf7eb, to:0x7fe133950fc010ce41322d88f64f1918b9abb3a3, data:0xf8b2cb4f000000000000000000000000fdf57e81872562a6112656f961944ce821fdf7eb }

注意，这个方法需要俩参数，处理一个JSONobject外，还有一个字符串参数，这俩可以为“”或者”latest”, “earliest” or “pending” 调用接口返回一个16进制字符串： 0x0000000000000000000000000000000000000000000000000000000000000071就是该账号的代币数量，转换为十进制为：113，与控制查询一致。

这就是一个智能合约的交互过程。是不是很简单啊。

转自：https://blog.csdn.net/ddffr/article/details/76549320

安利两个实战教程：

1.适合区块链新手的以太坊DApp开发

2.用区块链、星际文件系统（IPFS）、Node.js和MongoDB来构建电商平台

本文参与腾讯云自媒体同步曝光计划，分享自作者个人站点/博客。

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