js区块链源码
❶ 区块链养成源码服务商都有哪些
云豹网络,技术可以信得过
❷ 区块链养成源码哪家好
可以去看云豹网络公司,团队经验丰富
❸ 开源区块链浏览器源码怎样安装到虚拟主机
网络搜索 zotero 的浏览器插件,下载(解压)会得到一个crx 文件,可用压缩软件解压查看里面的源码,包括 json 、html 、js 等文件。相当于一个web控件,不过这个安装在浏览器中的可能对你浏览的所有网页都起作用。不过直接看源码很难看得懂,我最近也在学习制作浏览器插件,大家有什么好的学习方法也希望一起分享交流~
❹ 区块链项目的代码都需要来源吗为什么
区块链是一个共识机制,这意味着这种参与者必须是透明的,也就是说,这种运行的代码必须是开源代码,所谓开源代码,就是代码都是可见的。
每个人可以编译并执行自己编译的程序,也意味着每个人都可以修改其中的代码并运行,现在机制下,可以做到不管如何修改代码,只要这些修改代码的人没有超过51%,那这种修改是没有意义的,反而浪费自己的算力。
所以,至少参与的人,必须是需要知道代码的,如果一个区块链项目,代码没有开源,那么那么运行他的程序的节点都是不透明的,相当于你把他的代理人装到了自己的节点上,要代表这个所有人执行命令了。相当于系统开发商控制了整个网络。这种区块链怎么可行呢?
从理念角度去看,将区块链项目比作机器的话,本身的工作机制是透明的,是一个可以信任的机器。对此是这样理解的,第一,开源是区块链项目的一个必选项,而不是可选项,不论是公有链还是联盟项目都需要进行开源;第二,开源和交付源代码,是两个不同的概念,交付源代码并非是公开、透明,大家共同参与的一个过程。
比如在以太坊中,曾经因为在其平台上运行的某个平台币,存在漏洞,需要进行修改,这种修改是直接体现在代码上的,阅读代码的过程中,就发现有多处出现该币的相关代码,就是用于处理一旦碰见了这个问题,节点应如何处理,这些处理方法都是开源代码里写的,每个人都可以阅读,如果节点的负责人认可这种解决方案,他就会运行这个程序,相当于支持这种代码的决定,事实上区块链也就是通过这种机制来实现。
❺ 比特币区块链的前端到后端的工作处理流程
比特区块连接的前端到后端的工作流程,应该是一个非常详细的流程。
❻ 有靠谱的区块链宠物游戏源码吗
可以去github看一下eth上姨太猫的源码
❼ 如何用JavaScript实现区块链
<span style="font-family:Arial, Helvetica, sans-serif;">'use strict';</span>var CryptoJS = require("crypto-js");var express = require("express");var bodyParser = require('body-parser');var WebSocket = require("ws");var http_port = process.env.HTTP_PORT || 3001;var p2p_port = process.env.P2P_PORT || 6001;var initialPeers = process.env.PEERS ? process.env.PEERS.split(',') : [];class Block { constructor(index, previousHash, timestamp, data, hash) { this.index = index; this.previousHash = previousHash.toString(); this.timestamp = timestamp; this.data = data; this.hash = hash.toString(); }}var sockets = [];var MessageType = { QUERY_LATEST: 0, QUERY_ALL: 1, RESPONSE_BLOCKCHAIN: 2};var getGenesisBlock = () => { return new Block(0, "0", 1465154705, "my genesis block!!", "");};var blockchain = [getGenesisBlock()];var initHttpServer = () => { var app = express(); app.use(bodyParser.json()); app.get('/blocks', (req, res) => res.send(JSON.stringify(blockchain))); app.post('/mineBlock', (req, res) => { var newBlock = generateNextBlock(req.body.data); addBlock(newBlock); broadcast(responseLatestMsg()); console.log('block added: ' + JSON.stringify(newBlock)); res.send(); }); app.get('/peers', (req, res) => { res.send(sockets.map(s => s._socket.remoteAddress + ':' + s._socket.remotePort)); }); app.post('/addPeer', (req, res) => { connectToPeers([req.body.peer]); res.send(); }); app.listen(http_port, () => console.log('Listening http on port: ' + http_port));};var initP2PServer = () => { var server = new WebSocket.Server({port: p2p_port}); server.on('connection', ws => initConnection(ws)); console.log('listening websocket p2p port on: ' + p2p_port);};var initConnection = (ws) => { sockets.push(ws); initMessageHandler(ws); initErrorHandler(ws); write(ws, queryChainLengthMsg());};var initMessageHandler = (ws) => { ws.on('message', (data) => { var message = JSON.parse(data); console.log('Received message' + JSON.stringify(message)); switch (message.type) { case MessageType.QUERY_LATEST: write(ws, responseLatestMsg()); break; case MessageType.QUERY_ALL: write(ws, responseChainMsg()); break; case MessageType.RESPONSE_BLOCKCHAIN: handleBlockchainResponse(message); break; } });};var initErrorHandler = (ws) => { var closeConnection = (ws) => { console.log('connection failed to peer: ' + ws.url); sockets.splice(sockets.indexOf(ws), 1); }; ws.on('close', () => closeConnection(ws)); ws.on('error', () => closeConnection(ws));};var generateNextBlock = (blockData) => { var previousBlock = getLatestBlock(); var nextIndex = previousBlock.index + 1; var nextTimestamp = new Date().getTime() / 1000; var nextHash = calculateHash(nextIndex, previousBlock.hash, nextTimestamp, blockData); return new Block(nextIndex, previousBlock.hash, nextTimestamp, blockData, nextHash);};var calculateHashForBlock = (block) => { return calculateHash(block.index, block.previousHash, block.timestamp, block.data);};var calculateHash = (index, previousHash, timestamp, data) => { return CryptoJS.SHA256(index + previousHash + timestamp + data).toString();};var addBlock = (newBlock) => { if (isValidNewBlock(newBlock, getLatestBlock())) { blockchain.push(newBlock); }};var isValidNewBlock = (newBlock, previousBlock) => { if (previousBlock.index + 1 !== newBlock.index) { console.log('invalid index'); return false; } else if (previousBlock.hash !== newBlock.previousHash) { console.log('invalid previoushash'); return false; } else if (calculateHashForBlock(newBlock) !== newBlock.hash) { console.log(typeof (newBlock.hash) + ' ' + typeof calculateHashForBlock(newBlock)); console.log('invalid hash: ' + calculateHashForBlock(newBlock) + ' ' + newBlock.hash); return false; } return true;};var connectToPeers = (newPeers) => { newPeers.forEach((peer) => { var ws = new WebSocket(peer); ws.on('open', () => initConnection(ws)); ws.on('error', () => { console.log('connection failed') }); });};var handleBlockchainResponse = (message) => { var receivedBlocks = JSON.parse(message.data).sort((b1, b2) => (b1.index - b2.index)); var latestBlockReceived = receivedBlocks[receivedBlocks.length - 1]; var latestBlockHeld = getLatestBlock(); if (latestBlockReceived.index > latestBlockHeld.index) { console.log('blockchain possibly behind. We got: ' + latestBlockHeld.index + ' Peer got: ' + latestBlockReceived.index); if (latestBlockHeld.hash === latestBlockReceived.previousHash) { console.log("We can append the received block to our chain"); blockchain.push(latestBlockReceived); broadcast(responseLatestMsg()); } else if (receivedBlocks.length === 1) { console.log("We have to query the chain from our peer"); broadcast(queryAllMsg()); } else { console.log("Received blockchain is longer than current blockchain"); replaceChain(receivedBlocks); } } else { console.log('received blockchain is not longer than received blockchain. Do nothing'); }};var replaceChain = (newBlocks) => { if (isValidChain(newBlocks) && newBlocks.length > blockchain.length) { console.log('Received blockchain is valid. Replacing current blockchain with received blockchain'); blockchain = newBlocks; broadcast(responseLatestMsg()); } else { console.log('Received blockchain invalid'); }};var isValidChain = (blockchainToValidate) => { if (JSON.stringify(blockchainToValidate[0]) !== JSON.stringify(getGenesisBlock())) { return false; } var tempBlocks = [blockchainToValidate[0]]; for (var i = 1; i < blockchainToValidate.length; i++) { if (isValidNewBlock(blockchainToValidate[i], tempBlocks[i - 1])) { tempBlocks.push(blockchainToValidate[i]); } else { return false; } } return true;};var getLatestBlock = () => blockchain[blockchain.length - 1];var queryChainLengthMsg = () => ({'type': MessageType.QUERY_LATEST});var queryAllMsg = () => ({'type': MessageType.QUERY_ALL});var responseChainMsg = () =>({ 'type': MessageType.RESPONSE_BLOCKCHAIN, 'data': JSON.stringify(blockchain)});var responseLatestMsg = () => ({ 'type': MessageType.RESPONSE_BLOCKCHAIN, 'data': JSON.stringify([getLatestBlock()])});var write = (ws, message) => ws.send(JSON.stringify(message));var broadcast = (message) => sockets.forEach(socket => write(socket, message));connectToPeers(initialPeers);initHttpServer();initP2PServer();
❽ 哪里有区块链网站模板
没有的,模板是骗人的,都要自己开发,你可以看看资讯站,找区块链资讯类型的网站特别容易,你可以网络一下“区块链网”便可,“区块链XX网”之类的资讯站,国内至少上千家。不介绍了,你自己网络一下吧。
❾ 区块链开源技术有哪些
我只说我较为了解的吧,一个是基于比特币系统做的开源项目,叫cravecoin ,另外一个就是以太坊。我们一开始选择cravecoin来进行源码分析想在它之上进行二次开发,但因为以太坊开放性更好,而且很好地支持智能合约,所以分析了一段时间就放弃了。
然后进入以太坊的研究,一开始也想从底层源码进行动刀,但是整个过程比较艰辛,重新分析我们的需求后觉得利用其现有接口,也能进行一定开发,满足一些需要,所以把源码的注释都翻译完,基本搞清楚每个模块的作用后也不再进行进一步的修改工作了,毕竟以太坊也是几十个大牛花了很长时间才做出来的项目,
我们很难段时间内成功地把它改造成我们想要的样子,能实现目的,还是越快越容易越好。
而且有一个很重要的问题,要是把以太坊改了,就连不上它的公网了,用不了它世界第二的算力总量,这是一个本末倒置的问题。好像答非所问,但是主要想表达的是,题主如果想做开发,还是认真分析好一个项目就够了,
毕竟逻辑差不多。要学习更多的区块链知识,关注『区视网』
❿ node.js可以开发区块链吗
好一个母老虎!”林惇夫人大叫,把她放开,痛得直甩她的手。“看在上帝的份上,