SenShaMart/app/p2p-server.js
2022-11-24 12:03:27 +11:00

104 lines
No EOL
2.5 KiB
JavaScript

const Websocket = require('ws');
const P2P_PORT = process.env.P2P_PORT || 5000;
const peers = process.env.PEERS ? process.env.PEERS.split(',') : [];
const MESSAGE_TYPES = {
chain: 'CHAIN',
transaction: 'TRANSACTION',
clear_transactions: 'CLEAR_TRANSACTIONS',
metadata: 'METADATA'
};
class P2pServer {
constructor(blockchain, transactionPool) {
this.blockchain = blockchain;
this.transactionPool = transactionPool;
this.sockets = [];
}
listen() {
const server = new Websocket.Server({ port: P2P_PORT });
server.on('connection', socket => this.connectSocket(socket));
this.connectToPeers();
console.log(`Listening for peer-to-peer connections on: ${P2P_PORT}`);
}
connectToPeers() {
peers.forEach(peer => {
const socket = new Websocket(peer);
socket.on('open', () => this.connectSocket(socket));
});
}
connectSocket(socket) {
this.sockets.push(socket);
console.log('Socket connected');
this.messageHandler(socket);
this.sendChain(socket);
}
messageHandler(socket) {
socket.on('message', message => {
const data = JSON.parse(message);
switch(data.type) {
case MESSAGE_TYPES.chain:
this.blockchain.replaceChain(data.chain);
break;
case MESSAGE_TYPES.transaction:
this.transactionPool.updateOrAddTransaction(data.transaction);
break;
case MESSAGE_TYPES.metadata:
this.transactionPool.updateOrAddMetadata(data.metadata);
break;
case MESSAGE_TYPES.clear_transactions:
this.transactionPool.clear();
break;
}
});
}
sendChain(socket) {
socket.send(JSON.stringify({
type: MESSAGE_TYPES.chain,
chain: this.blockchain.chain
}));
}
sendTransaction(socket, transaction) {
socket.send(JSON.stringify({
type: MESSAGE_TYPES.transaction,
transaction
}));
}
sendMetadata(socket, metadata) {
socket.send(JSON.stringify({
type: MESSAGE_TYPES.metadata,
metadata
}));
}
syncChains() {
this.sockets.forEach(socket => this.sendChain(socket));
}
broadcastTransaction(transaction) {
this.sockets.forEach(socket => this.sendTransaction(socket, transaction));
}
broadcastMetadata(metadata) {
this.sockets.forEach(socket => this.sendMetadata(socket, metadata));
}
broadcastClearTransactions() {
this.sockets.forEach(socket => socket.send(JSON.stringify({
type: MESSAGE_TYPES.clear_transactions
})));
}
}
module.exports = P2pServer;