import { clearTimeout, setTimeout } from "timers"; import { pack, unpack } from "msgpackr"; export default class RpcQuery { constructor(network, query) { this._timeout = false; this._completed = false; this._responses = {}; this._network = network; this._query = query; this.init(); } get promise() { return this._promise; } handeTimeout() { this.resolve(false, true); } resolve(data, timeout = false) { clearTimeout(this._timeoutTimer); this._timeout = timeout; this._completed = true; // @ts-ignore this._promiseResolve(data); } async init() { this._promise = this._promise ?? new Promise((resolve) => { this._promiseResolve = resolve; }); this._timeoutTimer = this._timeoutTimer ?? setTimeout(this.handeTimeout.bind(this), this._network.queryTimeout * 1000); await this._network.ready; const promises = []; // tslint:disable-next-line:forin for (const relay of this._network.relays) { promises.push(this.queryRelay(relay)); } await Promise.allSettled(promises); this.checkResponses(); } async queryRelay(relay) { const socket = this._network.dht.connect(Buffer.from(relay, "hex")); return new Promise((resolve, reject) => { socket.on("data", (res) => { socket.end(); const response = unpack(res); if (response && response.error) { return reject(response); } this._responses[relay] = response; resolve(null); }); socket.on("error", (error) => reject({ error })); socket.write(pack(this._query)); }); } checkResponses() { const responses = {}; const responseStore = this._responses; const responseStoreKeys = Object.keys(responseStore); // tslint:disable-next-line:forin for (const peer in responseStore) { const responseIndex = responseStoreKeys.indexOf(peer); responses[responseIndex] = responses[responseIndex] ?? 0; responses[responseIndex]++; } for (const responseIndex in responses) { if (responses[responseIndex] / responseStoreKeys.length >= this._network.majorityThreshold) { const response = responseStore[responseStoreKeys[parseInt(responseIndex, 10)]]; // @ts-ignore if (null === response || null === response?.data) { this.retry(); return; } this.resolve(response?.data); } } } retry() { this._responses = {}; if (this._completed) { return; } this.init(); } }