以太坊（Ethereum）是一个开源的有智能合约功能的公共区块链平台。通过其专用加密货币以太币（Ether）提供去中心化的虚拟机（“以太虚拟机” Ethereum Virtual Machine）来处理点对点合约。

关于以太坊（Ethereum）的概念网上有很多资料可以查询，本文只上干货，主要目的如下：

搭建Ethereum的开发环境
熟悉Ethereum DAPP开发框架:Truffle
Truffle DAPP开发和调试

以太坊开发环境搭建

安装区块链仿真环境(ganache)、solidity编译器、web3、truffle。

npm install -g ganache-cli solc web3 truffle

IDE

Atom

安装linter-solidity插件。

$ apm install linter
$ apm install linter-solidity

ethereum客户端这里使用Metamask,下载对应的浏览器版本，安装到浏览器的插件里。

选择Custom RPC加入本地ganche私有链-“http://127.0.0.1:7545"。

开启环境

开启仿真环境ganache

metamask连接私有链 Customer Rpc -> http://127.0.0.1:7545

Truffle

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有以下功能：

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。

Truffle 开发部署合约

创建工程

mkdir fibonacci
cd fibonacci
truffle init

工程目录结构如下： app/ - 你的应用文件运行的默认目录。这里面包括推荐的javascript文件和css样式文件目录，但你可以完全决定如何使用这些目录。 contract/ - Truffle默认的合约文件存放地址。 migrations/ - 存放发布脚本文件 test/ - 用来测试应用和合约的测试文件 truffle.js - Truffle的配置文件

编写一个基础智能合约

创建一个合约contracts/Fibonacci.sol:

pragma solidity ^0.4.22;

contract Fibonacci {

uint[] fibseries;
  // n = how many in the series to return
  function generateFib(uint n) public {
    // set 1st and 2nd entries
    fibseries.push(1);
    fibseries.push(1);
    // generate subsequent entries
    for (uint i=2; i < n ; i++) {
      fibseries.push(fibseries[i-1] + fibseries[i-2]);
    }
  }
}

generateFib:生成Fibonacci（斐波纳契）数列，公式fib(n)=fib(n-1)+fib(n-2)。

创建一个新的部署文件migrations/2_deploy_contracts.js。

var Fibonacci = artifacts.require("Fibonacci");

module.exports = function(deployer) {
  deployer.deploy(Fibonacci);
};

启动Ganache
修改工程目录下的truffle.js

module.exports = {
  networks: {
    development: {
      host: "127.0.0.1",
      port: 7545,
      network_id: "*"
    }
  }
};

编译并植入合约

truffle compile
truffle migrate

Using network 'development'.

Running migration: 1_initial_migration.js
  Deploying Migrations...
  ... 0x97f35c60501091e10315febe0d2f1d8a59cb413c38cc7c2b3538263a7c67d0bf
  Migrations: 0xf7f433a4a2f9bf3f364bb96abe6a07778a61e095
Saving successful migration to network...
  ... 0x17b700e3a580ddd28d7bb7110c33f5a8c94b8875c99138d466f8625056a47cd9
Saving artifacts...
Running migration: 2_deploy_contracts.js
  Deploying Fibonacci...
  ... 0xd1f02be04a76df173456b48777d740f65248cd5870c4e22c058cc6f658dc2f9e
  Fibonacci: 0xc9554c5818dac7e79dc398d85c4789b90618c5b7
Saving successful migration to network...
  ... 0xb987be952d829ca21a909e2f558abdae84cf6afe0c83c2070ab2ba8319f79672
Saving artifacts...

console debug

我们可以直接使用remix ide，调试非常的方便。这里我们虐一下自己，使用Truffle Console来进行调试。

进入console
truffle console

调用合约

truffle(development)> Fibonacci.deployed().then(function(instance){return instance.generateFib(10);});
{ tx: '0x0d10a3f875548131fdad0a27f916af5575fcf6ee47085e9d625d695eb2c11583',
  receipt:
   { transactionHash: '0x0d10a3f875548131fdad0a27f916af5575fcf6ee47085e9d625d695eb2c11583',
     transactionIndex: 0,
     blockHash: '0x7596a7239811b8586a2c60a9fad19d41ea8bb3be46e8ed3b8ebbfaf4c477b707',
     blockNumber: 5,
     gasUsed: 298373,
     cumulativeGasUsed: 298373,
     contractAddress: null,
     logs: [],
     status: '0x01',
     logsBloom: '0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000' },
  logs: [] }

调试transaction

先attache一条transaction，id为transactionHash值。

truffle(development)> debug 0x0d10a3f875548131fdad0a27f916af5575fcf6ee47085e9d625d695eb2c11583
Compiling ./contracts/Fibonacci.sol...
Compiling ./contracts/Migrations.sol...

Gathering transaction data...

Addresses affected:
 0xc9554c5818dac7e79dc398d85c4789b90618c5b7 - Fibonacci

Commands:
(enter) last command entered (step next)
(o) step over, (i) step into, (u) step out, (n) step next
(;) step instruction, (p) print instruction, (h) print this help, (q) quit
(b) toggle breakpoint, (c) continue until breakpoint
(+) add watch expression (`+:<expr>`), (-) remove watch expression (-:<expr>)
(?) list existing watch expressions
(v) print variables and values, (:) evaluate expression - see `v`

Commands即为调试命令行。

watch（+:）变量,按n逐行进行跟踪。

debug(development:0x0d10a3f8...)> +:i
8
debug(development:0x0d10a3f8...)> +:fibseries
[ 1, 1, 2, 3, 5, 8, 13, 21 ]
debug(development:0x0d10a3f8...)> n

Fibonacci.sol:

14:     // generate subsequent entries
15:     for (uint i=2; i < n ; i++) {
16:       fibseries.push(fibseries[i-1] + fibseries[i-2]);
                                     ^

:i
  8

:fibseries
  [ 1, 1, 2, 3, 5, 8, 13, 21 ]

异常信息调试

修改以下合约代码
```
...
for (uint i=1; i < n ; i++) {
...
```

重新编译部署合约

debug(development:0x65bb45af...)> compile --all

Transaction completed successfully.
truffle(development)> migrate --reset
Compiling ./contracts/Fibonacci.sol...
Writing artifacts to ./build/contracts

Using network 'development'.

Running migration: 1_initial_migration.js
  Replacing Migrations...
  ... 0x26fdc5c20b9f44e96e537e0b8474f867d7bd7d27ad7172b004c858d2dceb6f99
  Migrations: 0xd0ea55247c6035375c6e284a60946cd35550ced2
Saving successful migration to network...
  ... 0x0ad76d3073b05161327fc1f7dbd1c521360c305af872ff12b7f59befb73dfbd2
Saving artifacts...
Running migration: 2_deploy_contracts.js
  Replacing Fibonacci...
  ... 0x93ee91146a3a5fd23dad1e77249870c0edeb5cf6cd78cb7c9db6aab24f538634
  Fibonacci: 0x090b1fd13ee19ec7f8f3175ca54d5165a443c694
Saving successful migration to network...
  ... 0xbeb0d613fa72c67ecf720833a4985244a91b0d0dea1c36fc23195e00e7fd8c18
Saving artifacts...
truffle(development)> Fibonacci.deployed().then(function(instance){return instance.generateFib(10);});
Error: VM Exception while processing transaction: invalid opcode
    at XMLHttpRequest._onHttpResponseEnd (/home/lizorn/.nvm/versions/node/v10.0.0/lib/node_modules/truffle/build/webpack:/~/xhr2/lib/xhr2.js:509:1)
    at XMLHttpRequest._setReadyState (/home/lizorn/.nvm/versions/node/v10.0.0/lib/node_modules/truffle/build/webpack:/~/xhr2/lib/xhr2.js:354:1)
    at XMLHttpRequestEventTarget.dispatchEvent (/home/lizorn/.nvm/versions/node/v10.0.0/lib/node_modules/truffle/build/webpack:/~/xhr2/lib/xhr2.js:64:1)
    at XMLHttpRequest.request.onreadystatechange (/home/lizorn/.nvm/versions/node/v10.0.0/lib/node_modules/truffle/build/webpack:/~/web3/lib/web3/httpprovider.js:128:1)
    at /home/lizorn/.nvm/versions/node/v10.0.0/lib/node_modules/truffle/build/webpack:/~/truffle-provider/wrapper.js:134:1
    at /home/lizorn/.nvm/versions/node/v10.0.0/lib/node_modules/truffle/build/webpack:/~/web3/lib/web3/requestmanager.js:86:1
    at Object.InvalidResponse (/home/lizorn/.nvm/versions/node/v10.0.0/lib/node_modules/truffle/build/webpack:/~/web3/lib/web3/errors.js:38:1)

此处由于数组越界，控制窗口并没有返回transaction的ID，我们可以通过查看Ganache的Logs，找到对应的Transaction，然后按之前的方式进行调试。

区块链导论:以太坊（Ethereum）

以太坊开发环境搭建

IDE

开启环境

Truffle

Truffle 开发部署合约

console debug