httphttps區塊鏈

Ⅰ 如何用JavaScript實現區塊鏈

<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();

Ⅱ 目前比較火熱的區塊鏈交易所有哪些

目前中心化的交易所比較火熱的有幣安、GATE、火幣，GATE出入金比較方便。但去中心化交易是未來的一個趨勢，現在在去中心化交易這一塊國內做得比較好的是路印協議。

Ⅲ http://gg.mzh1.com這個網站：叫謎知網 是區塊鏈技術的嗎

是一個區塊鏈技術的綜合門戶網站

Ⅳ 國內最大的區塊鏈交易平台是哪裡

國盾區塊鏈交易中心是世界最權威的工信部頒發通用積 分應用試點單位工信部頒發互聯 網金融試點單位

Ⅳ 比特幣和區塊鏈是一樣的嗎有沒有什麼網站可以學習區塊鏈知識，也可以了解比特幣的。

比特幣是區塊鏈技術的一個應用，比特幣屬於數字貨幣，而數字貨幣僅僅是區塊鏈技術在金融領域的一個應用，歸屬於區塊鏈1.0領域。現在是處於區塊鏈2.0時代屬於智能合約的時代，據說區塊鏈3.0是底層公鏈開發。平時關注這些區塊鏈的知識是從幣眾裡面看到的，有很多區塊鏈的內容知識，學起來挺方便的，可以關注一下。

Ⅵ 小白適合什麼區塊鏈交易平台

幣易交易平台還不錯，我就在這上面玩.支持法幣交易，提現速度快，幣種優質，現在還有分紅送幣活動.

Ⅶ 區塊鏈如何在現實中起作用

區塊鏈不是萬能的，目前落地的基本沒有多少，你非想要和超市掛鉤，我只能想到現在支付用的是支付寶或者微信，硬要用區塊鏈手段支付的話唯一可能的好處是不需要第三方機構做擔保(阿里巴巴和騰訊)節省了成本，並且阿里巴巴和騰訊有跑路風險(雖然目前看幾乎不可能)，用區塊鏈不會擔心程序叛變

Ⅷ 區塊鏈如何開發

分享區視網：

區塊鏈技術的應用范圍還是很廣的，基於去中心化，去信任，集體維護，可靠資料庫等特點，其在金融行業的應用是先行一步的。
區塊鏈是比特幣的底層技術，區塊鏈在數字貨幣的應用開發已經是成熟的了。

像英唐眾創提供的基於區塊鏈的交易系統開發方案，開發出來的軟體系統有很大的安全系數和透明度。