以太坊ETH DAPP开发（1）：实战开发基于truffle

一、开发环境配置

1、硬件配置

2、依赖工具版本

~/eth_workspace$geth version
Geth
Version: 1.8.18-stable
Architecture: amd64
Protocol Versions: [63 62]
Network Id: 1
Go Version: go1.11.2
Operating System: darwin
GOPATH=/Users/wujinquan/go
GOROOT=/usr/local/Cellar/go/1.10.3/libexec
~/eth_workspace$npm -v
6.4.1
~/eth_workspace$node -v
v11.2.0
~/eth_workspace$truffle version
Truffle v4.1.14 (core: 4.1.14)
Solidity v0.4.24 (solc-js)
~/eth_workspace$

二、智能合约开发部署过程

1、项目源码地址

2、建立一个独立的目录

~/gitmakenoise/conference$ls
README.md
~/gitmakenoise/conference$mkdir truffle
~/gitmakenoise/conference$cd truffle/

3、运行truffle init创建默认的合约项目

• contracts/: 智能合约存放的目录，默认情况下已经帮你创建 Migrations.sol合约。
• migrations/: 存放部署脚本
• test/: 存放测试脚本
• truffle.js: truffle的配置文件

~/gitmakenoise/conference/truffle$truffle init
Downloading...
Unpacking...
Setting up...
Unbox successful. Sweet!

Commands:

  Compile:        truffle compile
  Migrate:        truffle migrate
  Test contracts: truffle test
~/gitmakenoise/conference/truffle$tree
.
├── contracts
│   └── Migrations.sol
├── migrations
│   └── 1_initial_migration.js
├── test
├── truffle-config.js
└── truffle.js

3 directories, 4 files
~/gitmakenoise/conference/truffle$

4、修改truffle.js文件，改成如下:

这里是设置我们稍后要部署智能合约的位置, 否则会报网络错误。

module.exports = {
  networks: {
        development: {
            host: "localhost",
            port: 8545,
            network_id: "*" // 匹配任何network id
         }
    }
};

5、修改/新建、编译智能合约

（1）进入contracts目录，这里是存放合约代码的地方，这里新建 Conference.sol合约

合约内容很简单，是一个针对会议的智能合约，通过它参会者可以买票，组织者可以设置参会人数上限，以及退款策略。

（2）编译智能合约

修改migrations下的1_initial_migration.js文件，改成如下：

//var Migrations = artifacts.require("./Migrations.sol");
var Conference = artifacts.require("./Conference.sol");

module.exports = function(deployer) {
  //deployer.deploy(Migrations);
  deployer.deploy(Conference);
};

6、编译合约项目

truffle compile --compile-all
Truffle仅默认编译自上次编译后被修改过的文件，来减少不必要的编译。如果你想编译全部文件，可以使用–compile-all选项。

然后会多出一个build目录，该目录下的文件都不要做任何的修改。

~/gitmakenoise/conference/truffle$truffle compile --compile-all
Compiling ./contracts/Conference.sol...
Compiling ./contracts/Migrations.sol...

Compilation warnings encountered:

/Users/wujinquan/gitmakenoise/conference/truffle/contracts/Conference.sol:13:2: Warning: Defining constructors as functions with the same name as the contract is deprecated. Use "constructor(...) { ... }" instead.
	function Conference() {
 ^ (Relevant source part starts here and spans across multiple lines).
,/Users/wujinquan/gitmakenoise/conference/truffle/contracts/Conference.sol:21:4: Warning: "throw" is deprecated in favour of "revert()", "require()" and "assert()".
			throw; // throw ensures funds will be returned
			^---^
,/Users/wujinquan/gitmakenoise/conference/truffle/contracts/Conference.sol:25:3: Warning: Invoking events without "emit" prefix is deprecated.
		Deposit(msg.sender, msg.value);
		^----------------------------^
,/Users/wujinquan/gitmakenoise/conference/truffle/contracts/Conference.sol:38:5: Warning: Failure condition of 'send' ignored. Consider using 'transfer' instead.
				recipient.send(amount);
				^--------------------^
,/Users/wujinquan/gitmakenoise/conference/truffle/contracts/Conference.sol:39:5: Warning: Invoking events without "emit" prefix is deprecated.
				Refund(recipient, amount);
				^-----------------------^
,/Users/wujinquan/gitmakenoise/conference/truffle/contracts/Conference.sol:49:4: Warning: "suicide" has been deprecated in favour of "selfdestruct"
			suicide(organizer);
			^----------------^
,/Users/wujinquan/gitmakenoise/conference/truffle/contracts/Conference.sol:13:2: Warning: No visibility specified. Defaulting to "public".
	function Conference() {
 ^ (Relevant source part starts here and spans across multiple lines).
,/Users/wujinquan/gitmakenoise/conference/truffle/contracts/Conference.sol:47:2: Warning: No visibility specified. Defaulting to "public".
	function destroy() {
 ^ (Relevant source part starts here and spans across multiple lines).

Writing artifacts to ./build/contracts

~/gitmakenoise/conference/truffle$

7、运行testrpc

开启一个终端，输入testrpc运行测试节点。testrpc是一个完整的在内存中的区块链测试环境，启动 testrpc 经后，会默认创建10个帐号，Available Accounts是帐号列表，Private Keys是相对应的帐号密钥。

~/eth_workspace$testrpc
EthereumJS TestRPC v6.0.3 (ganache-core: 2.0.2)

Available Accounts
==================
(0) 0x91d16ebaf685844a45f78f539b9f391445509937
(1) 0x1602a3cc58b3884bceb22c3cdfc57d73ecdc705d
(2) 0x4b675ac76bd27870c3b301098d4445f7bd1c3095
(3) 0xe2790185a701a21d2d36fccbe5761c4ac637e743
(4) 0x3071e412a0a2b158bb3c48de60eede057c47dfbf
(5) 0x9398d2b8e6265bf0a4e583145caec839ef0257fb
(6) 0xa47f8c5d8acc4cd2c3c4e5e4a8a0b16f1eb35d7a
(7) 0xff719fd90a008cbc7433bea42cc9944667bc4624
(8) 0x8e0407dec67002c5fb99602dbe24dc2f544b7501
(9) 0xbeb3a9b7b0a0ff13e4bdc1c6f0e075325e4214b4

Private Keys
==================
(0) 1a54e7b8c8ceaa63ff2c02890dd12e654eea0829c5ef86fd8ec2a94b80d85a9a
(1) 9434af16caf5be665bb39aab976637341bba69b21994fab3094c391efa4afee1
(2) 0d963e5fa979650fa4cbfe49edcb0a358f356549ff040adeaf60329b26b2077c
(3) 206f6dbacf5e02fd379dcc5692cd9f3ee3bf31c21846c7cc7017874a1113831d
(4) 24cd5f53246c0012e2d6e0c3af8213bea5ab754ce5a11057adbcd113633c5384
(5) a01d3901222ae73a9a67a6a2aeac32214748237e47b001feb1f0236671e41a80
(6) 12a864c793fd71fbfee6d5e18d7c5f0c5cedaffd14eb3b513db9cf405f682c12
(7) fa4a1aa1869f618a987927433366b2511f988b4a48d315c90bb6f39066408c54
(8) a6694dd3dad7b4399a8ab50649667ef7435a2c0ef7e88c3d8452194b062f9929
(9) d9c8ca783379dea8b272062dce2919f163656749c98c571fe5502789281bd2f7

HD Wallet
==================
Mnemonic:      assume atom always scene enroll group cave chest veteran security tail zoo
Base HD Path:  m/44'/60'/0'/0/{account_index}

Listening on localhost:8545

8、truffle调用以太坊的接口

(1) 进入truffle 终端

~/gitmakenoise/conference/truffle$truffle console
truffle(development)>

(2) 调用以太坊接口

以太坊提供了一个web3.js库来访问以太坊内部的方法或者命令。
我们可以在truffle终端中调用下web3的方法，在truffle终端中输入web3.eth，你会得到一堆输出

truffle(development)> web3.eth
Eth {
  _requestManager:
   RequestManager {
     provider:
      HttpProvider {
        host: 'http://localhost:8545',
        timeout: 0,
        user: undefined,
        password: undefined,
        headers: undefined,
        send: [Function],
        sendAsync: [Function],
        _alreadyWrapped: true },
     polls: {},
     timeout: null },
  getBalance:
   { [Function: send] request: [Function: bound ], call: 'eth_getBalance' },
  getStorageAt:
   { [Function: send] request: [Function: bound ], call: 'eth_getStorageAt' },
  getCode:
   { [Function: send] request: [Function: bound ], call: 'eth_getCode' },
  getBlock:
   { [Function: send] request: [Function: bound ], call: [Function: blockCall] },
  getUncle:
   { [Function: send] request: [Function: bound ], call: [Function: uncleCall] },
  getCompilers:
   { [Function: send] request: [Function: bound ], call: 'eth_getCompilers' },
  getBlockTransactionCount:
   { [Function: send]
     request: [Function: bound ],
     call: [Function: getBlockTransactionCountCall] },
  getBlockUncleCount:
   { [Function: send]
     request: [Function: bound ],
     call: [Function: uncleCountCall] },
  getTransaction:
   { [Function: send]
     request: [Function: bound ],
     call: 'eth_getTransactionByHash' },
  getTransactionFromBlock:
   { [Function: send]
     request: [Function: bound ],
     call: [Function: transactionFromBlockCall] },
  getTransactionReceipt:
   { [Function: send]
     request: [Function: bound ],
     call: 'eth_getTransactionReceipt' },
  getTransactionCount:
   { [Function: send] request: [Function: bound ], call: 'eth_getTransactionCount' },
  call:
   { [Function: send] request: [Function: bound ], call: 'eth_call' },
  estimateGas:
   { [Function: send] request: [Function: bound ], call: 'eth_estimateGas' },
  sendRawTransaction:
   { [Function: send] request: [Function: bound ], call: 'eth_sendRawTransaction' },
  signTransaction:
   { [Function: send] request: [Function: bound ], call: 'eth_signTransaction' },
  sendTransaction:
   { [Function: send] request: [Function: bound ], call: 'eth_sendTransaction' },
  sign:
   { [Function: send] request: [Function: bound ], call: 'eth_sign' },
  compile:
   { solidity:
      { [Function: send] request: [Function: bound ], call: 'eth_compileSolidity' },
     lll:
      { [Function: send] request: [Function: bound ], call: 'eth_compileLLL' },
     serpent:
      { [Function: send] request: [Function: bound ], call: 'eth_compileSerpent' } },
  submitWork:
   { [Function: send] request: [Function: bound ], call: 'eth_submitWork' },
  getWork:
   { [Function: send] request: [Function: bound ], call: 'eth_getWork' },
  coinbase: [Getter],
  getCoinbase: { [Function: get] request: [Function: bound ] },
  mining: [Getter],
  getMining: { [Function: get] request: [Function: bound ] },
  hashrate: [Getter],
  getHashrate: { [Function: get] request: [Function: bound ] },
  syncing: [Getter],
  getSyncing: { [Function: get] request: [Function: bound ] },
  gasPrice: [Getter],
  getGasPrice: { [Function: get] request: [Function: bound ] },
  accounts: [Getter],
  getAccounts: { [Function: get] request: [Function: bound ] },
  blockNumber: [Getter],
  getBlockNumber: { [Function: get] request: [Function: bound ] },
  protocolVersion: [Getter],
  getProtocolVersion: { [Function: get] request: [Function: bound ] },
  iban:
  ....

9、部署合约到testrpc

truffle migrate --reset
这个命令会执行所有migrations目录下的js文件。如果之前执行过truffle migrate命令，再次执行，只会部署新的js文件，如果没有新的js文件，不会起任何作用。如果使用–reset参数，则会重新的执行所有脚本的部署。

~/gitmakenoise/conference/truffle$truffle migrate --reset
Using network 'development'.

Running migration: 1_initial_migration.js
  Deploying Conference...
  # 部署成功的txid
  ... 0xe1a21217d843a13df1613f6b3fe22200626aef0bc4281a8fc1cc3b2f3e7dd289
  # 合约地址
  Conference: 0x2233e07a9db44e0ca74e057b0589ef928e5113f8
Saving artifacts...
~/gitmakenoise/conference/truffle$

例如查询账户

truffle(development)> web3.eth.accounts
[ '0x91d16ebaf685844a45f78f539b9f391445509937',
  '0x1602a3cc58b3884bceb22c3cdfc57d73ecdc705d',
  '0x4b675ac76bd27870c3b301098d4445f7bd1c3095',
  '0xe2790185a701a21d2d36fccbe5761c4ac637e743',
  '0x3071e412a0a2b158bb3c48de60eede057c47dfbf',
  '0x9398d2b8e6265bf0a4e583145caec839ef0257fb',
  '0xa47f8c5d8acc4cd2c3c4e5e4a8a0b16f1eb35d7a',
  '0xff719fd90a008cbc7433bea42cc9944667bc4624',
  '0x8e0407dec67002c5fb99602dbe24dc2f544b7501',
  '0xbeb3a9b7b0a0ff13e4bdc1c6f0e075325e4214b4' ]
truffle(development)>

10、在testrpc窗口

Listening on localhost:8545
net_version
eth_accounts
eth_accounts
net_version
net_version
eth_sendTransaction
 # Transaction为第8中的txid
  Transaction: 0xe1a21217d843a13df1613f6b3fe22200626aef0bc4281a8fc1cc3b2f3e7dd289
  # Contract为为第8中的合约地址
  Contract created: 0x2233e07a9db44e0ca74e057b0589ef928e5113f8
  Gas usage: 528285
  Block Number: 1
  Block Time: Fri Nov 23 2018 20:30:10 GMT+0800 (中国标准时间)

11、在truffle 终端中查看合约相关信息

通过truffle框架教程查看相关命令，确认合约部署成功

#将合约重命名为app并生成命令用于调试
truffle(development)> Conference.deployed().then(function(instance) { app = instance})
undefined  #原因暂时忽略
truffle(development)> app.address #查看合约地址，可见与第10点中合约地址一致
'0x2233e07a9db44e0ca74e057b0589ef928e5113f8'
truffle(development)> app.quota() #查看合约中的变量，可见与contracts/Conference.sol中一致
BigNumber { s: 1, e: 2, c: [ 100 ] }
truffle(development)> app.organizer() #查看合约的部署者，可见为第9点中testrpc中的第一个账户
'0x91d16ebaf685844a45f78f539b9f391445509937'

12、在test目录新增一个conference.js测试文件

执行 truffle test

~/gitmakenoise/conference/truffle$truffle test
Using network 'development'.

start testing


  Contract: Conference
    ✓ Initial conference settings should match (132ms)
    ✓ Should update quota (118ms)
    ✓ Should let you buy a ticket (555ms)
    ✓ Should issue a refund by owner only (687ms)


  4 passing (2s)

~/gitmakenoise/conference/truffle$truffle -h

可在testrpc窗口见到相应的打印信息

三、编写web应用

1、 执行npm init，然后一路回车

~/gitmakenoise/conference/truffle$npm init
This utility will walk you through creating a package.json file.
It only covers the most common items, and tries to guess sensible defaults.

See `npm help json` for definitive documentation on these fields
and exactly what they do.

Use `npm install <pkg>` afterwards to install a package and
save it as a dependency in the package.json file.

Press ^C at any time to quit.
package name: (truffle)
version: (1.0.0)
description:
entry point: (truffle.js)
test command:
git repository:
keywords:
author:
license: (ISC)
About to write to /Users/wujinquan/gitmakenoise/conference/truffle/package.json:

{
  "name": "truffle",
  "version": "1.0.0",
  "description": "",
  "main": "truffle.js",
  "directories": {
    "test": "test"
  },
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC"
}


Is this OK? (yes)
~/gitmakenoise/conference/truffle$

生成一个名为package.json的文件，定义了这个项目所需要的各种模块，以及项目的配置信息（比如名称、版本、许可证等元数据）。npm 命令根据这个配置文件，自动下载所需的模块，也就是配置项目所需的运行和开发环境。
编辑这个文件，在scripts部分增加两个命令，最终如下:

{
  "name": "conference",
  "version": "1.0.0",
  "description": "",
  "main": "truffle-config.js",
  "directories": {
    "test": "test"
  },
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "webpack",
    "server": "webpack-dev-server --open"
  },
  "author": "",
  "license": "ISC"
}

2、在truffle目录下新建app目录

此目录主要存放web前段html、js 、css文件，不多解释

3、使用webpack打包部署web

webpack环境问题，解决中，…未完待续

四、总结

1、Truffle框架开发优势

Truffle是一个世界级的开发环境，测试框架，以太坊的资源管理通道，致力于让以太坊上的开发变得简单，Truffle有以下优点：

• 内置的智能合约编译，链接，部署和二进制文件的管理。
• 快速开发下的自动合约测试。
• 脚本化的，可扩展的部署与发布框架。
• 部署到不管多少的公网或私网的网络环境管理功能
• 使用EthPM&NPM提供的包管理，使用ERC190标准。
• 与合约直接通信的直接交互控制台（写完合约就可以命令行里验证了）。
• 可配的构建流程，支持紧密集成。
• 在Truffle环境里支持执行外部的脚本。