ethereumjs/ethereumjs-vm-5-vm对象

1.运行文件

var Buffer = require('safe-buffer').Buffer // use for Node.js <4.5.0
var VM = require('./index.js')

// create a new VM instance
var vm = new VM({chain : 'rinkeby'})//设置连接的为Rinkeby链
console.log(vm);

2.分析返回的vm对象：

VM {
  opts: { chain: 'rinkeby' },
  _common:
   Common {
     _chainParams:
      { name: 'rinkeby',
        chainId: ,
        networkId: ,
        comment: 'PoA test network',
        url: 'https://www.rinkeby.io',
        genesis:
         { hash:
            '0x6341fd3daf94b748c72ced5a5b26028f2474f5f00d824504e4fa37a75767e177',
           timestamp: '0x58ee40ba',
           gasLimit: ,
           difficulty: ,
           nonce: '0x0000000000000000',
           extraData:
            '0x52657370656374206d7920617574686f7269746168207e452e436172746d616e42eb768f2244c8811c63729a21a3569731535f067ffc57839b00206d1ad20c69a1981b489f772031b279182d99e65703f0076e4812653aab85fca0f00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
           stateRoot:
            '0x53580584816f617295ea26c0e17641e0120cab2f0a8ffb53a866fd53aa8e8c2d' },
        hardforks:
         [ { name: 'chainstart', block: , consensus: 'poa', finality: null },
           { name: 'homestead', block: , consensus: 'poa', finality: null },
           { name: 'dao', block: null, consensus: 'poa', finality: null },
           { name: 'tangerineWhistle',
             block: ,
             consensus: 'poa',
             finality: null },
           { name: 'spuriousDragon',
             block: ,
             consensus: 'poa',
             finality: null },
           { name: 'byzantium',
             block: ,
             consensus: 'poa',
             finality: null },
           { name: 'constantinople',
             block: null,
             consensus: 'poa',
             finality: null },
           { name: 'hybridCasper',
             block: null,
             consensus: 'poa',
             finality: 'pos' } ],
        bootstrapNodes:
         [ { ip: '52.169.42.101',
             port: ,
             id:
              'a24ac7c5484ef4ed0c5eb2d36620ba4e4aa13b8c84684e1b4aab0cebea2ae45cb4d375b77eab56516d34bfbd3c1a833fc51296ff084b770b94fb9028c4d25ccf',
             location: 'IE',
             comment: '' },
           { ip: '52.3.158.184',
             port: ,
             id:
              '343149e4feefa15d882d9fe4ac7d88f885bd05ebb735e547f12e12080a9fa07c8014ca6fd7f373123488102fe5e34111f8509cf0b7de3f5b44339c9f25e87cb8',
             location: '',
             comment: 'INFURA' } ] },
     _hardfork: 'byzantium',
     _supportedHardforks: [ 'byzantium', 'constantinople' ] },
  stateManager:
   StateManager {
     _common:
      Common {
        _chainParams:
         { name: 'rinkeby',
           chainId: ,
           networkId: ,
           comment: 'PoA test network',
           url: 'https://www.rinkeby.io',
           genesis:
            { hash:
               '0x6341fd3daf94b748c72ced5a5b26028f2474f5f00d824504e4fa37a75767e177',
              timestamp: '0x58ee40ba',
              gasLimit: ,
              difficulty: ,
              nonce: '0x0000000000000000',
              extraData:
               '0x52657370656374206d7920617574686f7269746168207e452e436172746d616e42eb768f2244c8811c63729a21a3569731535f067ffc57839b00206d1ad20c69a1981b489f772031b279182d99e65703f0076e4812653aab85fca0f00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
              stateRoot:
               '0x53580584816f617295ea26c0e17641e0120cab2f0a8ffb53a866fd53aa8e8c2d' },
           hardforks://从这里可以看出到哪个区块使用的是哪个硬分叉的类型
            [ { name: 'chainstart', block: , consensus: 'poa', finality: null },//第0个，即初始区块使用的是chainstart
              { name: 'homestead', block: , consensus: 'poa', finality: null },//第一个区块使用的是homestead
              { name: 'dao', block: null, consensus: 'poa', finality: null },//没有使用这种硬分叉类型
              { name: 'tangerineWhistle',//第二个区块使用的是tangerineWhistle
                block: ,
                consensus: 'poa',
                finality: null },
              { name: 'spuriousDragon',//从三个区块到第1035300使用的是spuriousDragon
                block: ,
                consensus: 'poa',
                finality: null },
              { name: 'byzantium',//从第1035301个区块到后面使用的都是该硬分叉，现在同步到的区块应该都是第1035301个区块之后的区块了，所以应该满足的都是byzantium硬分叉
                block: ,
                consensus: 'poa',
                finality: null },
              { name: 'constantinople',//没有使用这种硬分叉类型
                block: null,
                consensus: 'poa',
                finality: null },
              { name: 'hybridCasper',//没有使用这种硬分叉类型
                block: null,
                consensus: 'poa',
                finality: 'pos' } ],
           bootstrapNodes://该区块链是通过连接该bootstrapNodes节点对应的区块链得到的，它会同步该节点上至今的所有区块，然后就能够在该Rinkeby区块链上进行操作了
            [ { ip: '52.169.42.101',
                port: ,
                id:
                 'a24ac7c5484ef4ed0c5eb2d36620ba4e4aa13b8c84684e1b4aab0cebea2ae45cb4d375b77eab56516d34bfbd3c1a833fc51296ff084b770b94fb9028c4d25ccf',
                location: 'IE',
                comment: '' },
              { ip: '52.3.158.184',
                port: ,
                id:
                 '343149e4feefa15d882d9fe4ac7d88f885bd05ebb735e547f12e12080a9fa07c8014ca6fd7f373123488102fe5e34111f8509cf0b7de3f5b44339c9f25e87cb8',
                location: '',
                comment: 'INFURA' } ] },
        _hardfork: 'byzantium',
        _supportedHardforks: [ 'byzantium', 'constantinople' ] },//设置的只支持的硬分叉
     _trie:
      SecureTrie {
        EMPTY_TRIE_ROOT:
         <Buffer  e8 1f  1b cc  a6 ff   e6  c0 f8 6e 5b  e0 1b  6c ad c0   2f b5 e3  b4 >,
        sem:
         { capacity: ,
           current: ,
              .............................

                         buffer: true,
                         type: 'ucs-2' },
                      utf16le:
                       { encode: [Function: encode],
                         decode: [Function: decode],
                         buffer: true,
                         type: 'utf16le' },
                      'utf-16le':
                       { encode: [Function: encode],
                         decode: [Function: decode],
                         buffer: true,
                         type: 'utf-16le' } } },
                _status: 'opening',
                location: '',
                db:
                 DeferredLevelDOWN {
                   location: '',
                   status: 'new',
                   _db: undefined,
                   _operations: [],
                   _iterators: [] } } ],
           _root:
            <Buffer  e8 1f  1b cc  a6 ff   e6  c0 f8 6e 5b  e0 1b  6c ad c0   2f b5 e3  b4 >,
           _scratch: null,
           _checkpoints: [],
           checkpoint: [Function: checkpoint],
           commit: [Function: commit],
           revert: [Function: revert],
           _enterCpMode: [Function: _enterCpMode],
           _exitCpMode: [Function: _exitCpMode],
           createScratchReadStream: [Function: createScratchReadStream],
           copy: [Function: bound copy],
           get: [Function: bound get],
           put: [Function: bound put],
           del: [Function: bound del] } },
     _touched: Set {},
     _touchedStack: [],
     _checkpointCount:  },
  blockchain:
   { fake: true,
     getBlock: [Function: getBlock],
     delBlock: [Function: delBlock],
     iterator: [Function: iterator] },
  allowUnlimitedContractSize: false,
  emitFreeLogs: false,
  _precompiled:
   { '': [Function],
     '': [Function],
     '': [Function],
     '': [Function],
     '': [Function],
     '': [Function],
     '': [Function],
     '': [Function] },
  _events: [Object: null prototype] {},
  _eventsCount: ,
  _maxListeners: undefined }

从上面得知url: 'https://www.rinkeby.io'，到该网站一查看：

1）其提供的连接该Rinkeby链的方法为：

https://www.rinkeby.io/#geth

geth --datadir=$HOME/.rinkeby init rinkeby.json

geth --networkid= --datadir=$HOME/.rinkeby --cache= --syncmode=full --ethstats='yournode:Respect my authoritah!@stats.rinkeby.io' --bootnodes=enode://a24ac7c5484ef4ed0c5eb2d36620ba4e4aa13b8c84684e1b4aab0cebea2ae45cb4d375b77eab56516d34bfbd3c1a833fc51296ff084b770b94fb9028c4d25ccf@52.169.42.101:30303

和vm返回对象中的bootstrapNodes值是相同的

2）从其提供的rinkeby.json-构造初始区块的文件得到：

{"config":{"chainId":,"homesteadBlock":,"eip150Block":,"eip150Hash":"0x0000000000000000000000000000000000000000000000000000000000000000","eip155Block":,"eip158Block":,"byzantiumBlock":,"clique":{"period":,"epoch":}},"nonce":"0x0","timestamp":"0x58ee40ba","extraData":"0x52657370656374206d7920617574686f7269746168207e452e436172746d616e42eb768f2244c8811c63729a21a3569731535f067ffc57839b00206d1ad20c69a1981b489f772031b279182d99e65703f0076e4812653aab85fca0f00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","gasLimit":"0x47b760","difficulty":"0x1","mixHash":"0x0000000000000000000000000000000000000000000000000000000000000000","coinbase":"0x0000000000000000000000000000000000000000",.....

其的各个部署信息extraData、timestamp、gasLimit、difficulty等值都是相同的，说明vm上的区块链的初始区块和这个Rinkeby链的初始区块相同

从其byzantiumBlock、homesteadBlock值中设置的硬分叉位置也与vm上的区块链的硬分叉配置相同

综上所述，说明设置的区块链连接的就是这个Rinkeby链，所以在该vm上交易或构建合约实际上就是运行在这个Rinkeby测试网络上