Initial commit
Once again a weird place to commit, I have already done a lot of work, but I am just bad at using git, okay.
This commit is contained in:
1
packages/widget/src/entry.ts
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1
packages/widget/src/entry.ts
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export * from './pow-captcha';
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458
packages/widget/src/pow-captcha.ts
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458
packages/widget/src/pow-captcha.ts
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import { LitElement, html, css, isServer, type PropertyValues } from 'lit';
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import { customElement, property, state } from 'lit/decorators.js';
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import { type ChallengeSolveRequest, type SolutionMessage, WorkerMessageType, type WorkerRequest, WorkerResponseType } from './types/worker';
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import { type Challenge, ChallengeStrategy } from '@impost/lib';
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import { get_wasm_module } from '@impost/lib/solver';
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import ChallengeWorker from './solver-worker?worker&inline';
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@customElement('pow-captcha')
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export class PowCaptcha extends LitElement {
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static override styles = css`
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:host {
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display: block;
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width: var(--impost-widget-width, 250px);
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}
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.impost-widget {
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display: flex;
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flex-direction: column;
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border: 1px solid var(--impost-widget-border-color, #505050);
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font-family: sans-serif;
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background-color: var(--impost-widget-background-color, #070408);
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border-radius: var(--impost-widget-border-radius, 8px);
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}
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.impost-main {
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display: flex;
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align-items: center;
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gap: 0.375rem;
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padding: 0.75rem;
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}
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.impost-main span {
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height: min-content;
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}
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.impost-checkbox {
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display: flex;
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align-items: center;
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justify-content: center;
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width: 1.5rem;
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height: 1.5rem;
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color: var(--impost-widget-checkbox-color, #6e6e6eff);
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}
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.impost-checkbox input {
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height: 80%;
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width: 80%;
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margin: 0;
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}
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.impost-footer {
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display: flex;
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padding: 0.25rem 0.75rem;
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font-size: 0.75rem;
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color: var(--impost-widget-footer-color, #a2a2a2);
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justify-content: space-around;
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align-items: end;
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}
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.impost-footer div {
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height: min-content;
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}
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.impost-footer #provider-link {
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margin-left: auto;
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}
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.impost-footer div a {
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color: var(--impost-widget-footer-color, #a2a2a2);
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}
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.impost-footer div a:hover {
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text-decoration: none;
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}
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.hidden {
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display: none;
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}
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`;
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// one of: "load", "focus", "submit", "off"
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@property({ type: String })
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auto: "onload" | "onfocus" | "onsubmit" | "off" = "off";
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@property({ type: String })
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challengeUrl: string = 'http://localhost:3000/api/pow';
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@property({ type: String })
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challengejson: string = '';
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// needed to allow for multiple widgets on the same page if you wanted to
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// do that for some reason
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uid: string = Math.floor(Math.random() * 100000).toString();
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@state()
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private solution: string = '';
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@state()
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private errorMessage: string = '';
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@state()
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private challengeData: Challenge | null = null;
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@state()
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private solved: boolean = false;
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@state()
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private isSolving: boolean = false;
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@state()
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private disabled: boolean = true;
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@state()
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private hashRate: number = 0;
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// stores the nonce and solution atomics
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private sab: SharedArrayBuffer = new SharedArrayBuffer(8);
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private solverWorkers: Worker[] | null = null;
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private solveStartTime: number | null = null;
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private hashRateInterval: number | null = null;
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override connectedCallback() {
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super.connectedCallback();
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this.fetchChallenge();
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this.initWorkers();
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switch (this.auto) {
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case 'onload':
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this.solveChallenge();
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break;
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case 'onfocus':
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this.addEventListener('focus', () => this.solveChallenge());
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break;
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case 'onsubmit':
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if (this.parentElement?.nodeName === 'FORM') {
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this.parentElement.addEventListener('submit', () => this.solveChallenge());
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}
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break;
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}
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}
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protected override firstUpdated(_changedProperties: PropertyValues): void {
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super.firstUpdated(_changedProperties);
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this.disabled = false;
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}
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override disconnectedCallback() {
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super.disconnectedCallback();
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if (this.hashRateInterval !== null) {
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clearInterval(this.hashRateInterval);
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this.hashRateInterval = null;
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}
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for (const worker of this.solverWorkers || []) {
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worker.terminate();
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this.solverWorkers = null;
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}
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}
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getCurrentWorkingNonce() {
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return Atomics.load(new Uint32Array(this.sab), 0);
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}
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async fetchChallenge() {
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this.errorMessage = '';
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if (this.challengeData !== null) {
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return;
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}
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if (this.challengejson !== '' && this.challengeData === null) {
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this.challengeData = JSON.parse(this.challengejson);
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this.challengejson = '';
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return;
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}
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if (isServer) {
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return;
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}
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await fetch(`${this.challengeUrl}/challenge`)
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.then(response => response.json())
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.then(data => {
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this.challengeData = data;
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})
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.catch(error => {
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console.error('Error fetching challenge:', error);
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this.errorMessage = 'Failed to fetch challenge. Please try again.';
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});
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}
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async initWorkers() {
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this.solverWorkers = [];
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const num_workers = navigator.hardwareConcurrency;
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for (let i = 0; i < num_workers; i++) {
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this.solverWorkers.push(new ChallengeWorker());
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}
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const atomics_view = new Int32Array(this.sab);
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Atomics.store(atomics_view, 0, 0);
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Atomics.store(atomics_view, 1, 0);
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let wasm_module = await get_wasm_module();
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let worker_promises: Promise<void>[] = [];
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for (let i = 0; i < this.solverWorkers.length; i++) {
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console.log('Worker', i);
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const worker = this.solverWorkers[i]!;
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worker_promises.push(new Promise<void>((resolve, reject) => {
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const message_handler = (event: MessageEvent<SolutionMessage>) => {
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console.log('Worker', i, 'got message', event.data);
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if (event.data.type === WorkerResponseType.Error) {
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console.error("Worker error:", event.data.error);
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reject(event.data.error);
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}
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if (event.data.type === WorkerResponseType.InitOk) {
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resolve();
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}
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reject(new Error("Unexpected message from worker"));
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};
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const error_handler = (error: ErrorEvent) => {
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console.error("Worker error:", error);
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reject(error);
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};
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worker.addEventListener('message', message_handler);
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worker.addEventListener('error', error_handler);
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worker.postMessage({
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type: WorkerMessageType.Init,
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module: wasm_module,
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sab: this.sab,
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} as WorkerRequest);
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}));
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}
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const timeoutMs = 10 * 1000;
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let timeout: number;
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const timeoutPromise = new Promise((_, reject) => {
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timeout = setTimeout(() => {
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this.errorMessage = 'Failed to initialize workers in time. Please refresh the page.';
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reject(new Error(`Function timed out after ${timeoutMs}ms`));
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}, timeoutMs);
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});
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await Promise.race([
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Promise.allSettled(worker_promises).then(() => {
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console.log('All workers initialized');
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}),
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timeoutPromise,
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]).then(() => {
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clearTimeout(timeout);
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});
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}
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async issueChallengeToWorker(worker: Worker, request: ChallengeSolveRequest): Promise<SolutionMessage> {
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return new Promise<SolutionMessage>((resolve, reject) => {
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const message_handler = (event: MessageEvent<SolutionMessage>) => {
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worker.removeEventListener('message', message_handler);
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worker.removeEventListener('error', error_handler);
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resolve(event.data);
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};
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const error_handler = (error: ErrorEvent) => {
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worker.removeEventListener('error', error_handler);
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worker.removeEventListener('message', message_handler);
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console.error("Worker error:", error);
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reject(error);
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};
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worker.addEventListener('message', message_handler);
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worker.addEventListener('error', error_handler);
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switch (request.strategy) {
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case ChallengeStrategy.LeadingZeroes:
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worker.postMessage({
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strategy: ChallengeStrategy.LeadingZeroes,
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salt: request.salt,
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difficulty: request.difficulty,
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} as WorkerRequest);
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break;
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case ChallengeStrategy.TargetNumber:
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worker.postMessage({
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strategy: ChallengeStrategy.TargetNumber,
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target: request.target,
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salt: request.salt,
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} as WorkerRequest);
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break;
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}
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});
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}
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async solveChallenge() {
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if (!this.challengeData || this.solverWorkers === null) {
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this.errorMessage = 'Captcha is not ready. Please wait or refresh.';
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return;
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}
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if (this.solution !== '') {
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return;
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}
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this.solveStartTime = performance.now();
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this.hashRateInterval = setInterval(async () => {
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const nonce = this.getCurrentWorkingNonce();
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this.hashRate = (nonce / ((performance.now() - this.solveStartTime!) / 1000));
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}, 250);
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this.dispatchEvent(new CustomEvent('impost:solve', {
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detail: {
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solution: this.solution,
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},
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bubbles: true,
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composed: true,
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}))
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console.log(this.challengeData);
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this.isSolving = true;
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this.errorMessage = '';
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this.solution = '';
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const atomics_view = new Int32Array(this.sab);
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Atomics.store(atomics_view, 0, 0);
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Atomics.store(atomics_view, 1, -1);
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let request: ChallengeSolveRequest;
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switch (this.challengeData.strategy) {
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case ChallengeStrategy.LeadingZeroes:
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request = {
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strategy: ChallengeStrategy.LeadingZeroes,
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salt: this.challengeData.salt,
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difficulty: this.challengeData.difficulty,
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};
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break;
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case ChallengeStrategy.TargetNumber:
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request = {
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strategy: ChallengeStrategy.TargetNumber,
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target: this.challengeData.target,
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salt: this.challengeData.salt,
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};
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break;
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}
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console.log('Sending challenge to workers...');
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// TODO: the first response is not always the solution, due to cmpxchg
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// blocking, some workers may block on the read, and as soon as they
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// unblock, they return 0 since the challenge is already solved.
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//
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// We need to do a better job of tracking solvers, so if one worker
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// errors out, we only error out if all workers have errored out.
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let worker_promises: Promise<SolutionMessage>[] = [];
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for (let worker of this.solverWorkers) {
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// dispatch to all workers, func is async so it will not block
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worker_promises.push(this.issueChallengeToWorker(worker, request));
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}
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let solution = await Promise.race(worker_promises);
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if (solution.type === WorkerResponseType.Error) {
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this.errorMessage = solution.error;
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return;
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}
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if (solution.type !== WorkerResponseType.Solution) {
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this.errorMessage = "Something went wrong, please try again later.";
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return;
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}
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this.solution = Atomics.load(atomics_view, 1).toString();
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this.isSolving = false;
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this.solved = true;
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if (this.hashRateInterval !== null) {
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clearInterval(this.hashRateInterval);
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this.hashRateInterval = null;
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}
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this.dispatchEvent(new CustomEvent('impost:solved', {
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detail: {
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solution: this.solution,
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},
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bubbles: true,
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composed: true,
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}))
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}
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solvePreventDefault(event: Event) {
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event.preventDefault();
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this.solveChallenge();
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}
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override render() {
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if (this.challengejson !== '' && this.challengeData === null) {
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this.challengeData = JSON.parse(this.challengejson);
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this.challengejson = '';
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}
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if (this.errorMessage) {
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return html`
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<div class="error-message">${this.errorMessage}</div>
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`;
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}
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if (this.challengeData === null) {
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return html`
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<div class="loading-message">Loading captcha challenge...</div>
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`;
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}
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return html`
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<div class="impost-widget">
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<div class="impost-main">
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<div class="impost-checkbox">
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${!this.isSolving ? html`
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<input type="checkbox" id="impost-checkbox-${this.uid}" @click=${this.solvePreventDefault} @change=${this.solvePreventDefault} ?disabled=${this.disabled} ?checked=${this.solved}>
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` : html`
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<svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 24 24">
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<!-- Icon from SVG Spinners by Utkarsh Verma - https://github.com/n3r4zzurr0/svg-spinners/blob/main/LICENSE -->
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<g stroke="currentColor">
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<circle cx="12" cy="12" r="9.5" fill="none" stroke-linecap="round" stroke-width="3">
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<animate attributeName="stroke-dasharray" calcMode="spline" dur="1.5s" keySplines="0.42,0,0.58,1;0.42,0,0.58,1;0.42,0,0.58,1" keyTimes="0;0.475;0.95;1" repeatCount="indefinite" values="0 150;42 150;42 150;42 150"/>
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<animate attributeName="stroke-dashoffset" calcMode="spline" dur="1.5s" keySplines="0.42,0,0.58,1;0.42,0,0.58,1;0.42,0,0.58,1" keyTimes="0;0.475;0.95;1" repeatCount="indefinite" values="0;-16;-59;-59"/>
|
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</circle>
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<animateTransform attributeName="transform" dur="2s" repeatCount="indefinite" type="rotate" values="0 12 12;360 12 12"/>
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</g>
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</svg>
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`}
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</div>
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<label for="impost-checkbox-${this.uid}">${this.solved ? 'Verified' : html`${this.isSolving ? 'Verifying...' : 'I am not a robot'}`}</label>
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</div>
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<div class="impost-footer">
|
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${this.isSolving && this.hashRate > 0 ? html`
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<div>
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<span>H/s:</span>
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<span>${this.hashRate.toFixed(2)}</span>
|
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</div>
|
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` : ``}
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<div id="provider-link">
|
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Protected by <a href="https://github.com/impost/pow-captcha" target="_blank">Impost</a>
|
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</div>
|
||||
</div>
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||||
</div>
|
||||
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<input
|
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type = "text"
|
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id = "impost-solution"
|
||||
class="hidden"
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||||
.value = ${this.solution}
|
||||
/>
|
||||
`;
|
||||
}
|
||||
}
|
||||
91
packages/widget/src/solver-worker.ts
Normal file
91
packages/widget/src/solver-worker.ts
Normal file
@@ -0,0 +1,91 @@
|
||||
// This worker just sits on another thread and waits for message to solve
|
||||
// challenges so that we dont block the render thread
|
||||
|
||||
import {
|
||||
type WorkerRequest,
|
||||
type SolutionMessage,
|
||||
WorkerMessageType,
|
||||
WorkerResponseType,
|
||||
} from "./types/worker";
|
||||
|
||||
import { ChallengeStrategy } from "@impost/lib";
|
||||
|
||||
import { type SolverModule, init_solver, solve_leaading_zeroes_challenge, solve_target_number_challenge } from '@impost/lib/solver';
|
||||
|
||||
let solver: SolverModule | null = null;
|
||||
|
||||
let atomic_nonce: Int32Array | null = null;
|
||||
let atomic_solution: Int32Array | null = null;
|
||||
|
||||
onmessage = async (event: MessageEvent<WorkerRequest>) => {
|
||||
if (event.data.type === WorkerMessageType.Init) {
|
||||
atomic_nonce = new Int32Array(event.data.sab, 0, 1);
|
||||
atomic_solution = new Int32Array(event.data.sab, 4, 1);
|
||||
let module = event.data.module;
|
||||
|
||||
try {
|
||||
solver = await init_solver({
|
||||
__get_solution: () => Atomics.load(atomic_solution!, 0),
|
||||
__set_solution: (value: number) => Atomics.store(atomic_solution!, 0, value),
|
||||
__cmpxchg_solution: (expected: number, replacement: number) => Atomics.compareExchange(atomic_solution!, 0, expected, replacement),
|
||||
__fetch_add_nonce: (value: number) => Atomics.add(atomic_nonce!, 0, value),
|
||||
}, module);
|
||||
} catch (error: any) {
|
||||
postMessage({
|
||||
type: WorkerResponseType.Error,
|
||||
error: `Could not load WASM solver: ${error.message}`,
|
||||
} as SolutionMessage);
|
||||
return;
|
||||
}
|
||||
|
||||
if (!solver) {
|
||||
postMessage({
|
||||
type: WorkerResponseType.Error,
|
||||
error: "Failed to load WASM solver",
|
||||
} as SolutionMessage);
|
||||
return;
|
||||
}
|
||||
|
||||
postMessage({
|
||||
type: WorkerResponseType.InitOk,
|
||||
} as SolutionMessage);
|
||||
return;
|
||||
}
|
||||
|
||||
if (!solver) {
|
||||
postMessage({
|
||||
type: WorkerResponseType.Error,
|
||||
error: "WASM solver not loaded",
|
||||
} as SolutionMessage);
|
||||
return;
|
||||
}
|
||||
|
||||
if (atomic_nonce === null || atomic_solution === null) {
|
||||
throw new Error("Atomics not initialized");
|
||||
}
|
||||
|
||||
const { strategy } = event.data;
|
||||
|
||||
let solution: number;
|
||||
switch (strategy) {
|
||||
case ChallengeStrategy.LeadingZeroes:
|
||||
solution = solve_leaading_zeroes_challenge(solver, event.data)
|
||||
break;
|
||||
case ChallengeStrategy.TargetNumber:
|
||||
solution = solve_target_number_challenge(solver, event.data)
|
||||
break;
|
||||
}
|
||||
|
||||
// we are just assuming that if its less than -1, its the min i32
|
||||
if (solution < 0) {
|
||||
return postMessage({
|
||||
type: WorkerResponseType.Error,
|
||||
error: "failed to solve challenge",
|
||||
} as SolutionMessage);
|
||||
}
|
||||
|
||||
postMessage({
|
||||
type: WorkerResponseType.Solution,
|
||||
nonce: solution === -1 ? null : solution.toString()
|
||||
} as SolutionMessage);
|
||||
};
|
||||
60
packages/widget/src/types/worker.ts
Normal file
60
packages/widget/src/types/worker.ts
Normal file
@@ -0,0 +1,60 @@
|
||||
import { ChallengeStrategy } from "@impost/lib";
|
||||
|
||||
export enum WorkerMessageType {
|
||||
Init = "init",
|
||||
Challenge = "challenge",
|
||||
}
|
||||
|
||||
interface WorkerInitRequest {
|
||||
type: WorkerMessageType.Init;
|
||||
module: WebAssembly.Module;
|
||||
|
||||
sab: SharedArrayBuffer;
|
||||
}
|
||||
|
||||
interface ChallengeLeadingZeroesSolveRequest {
|
||||
strategy: ChallengeStrategy.LeadingZeroes;
|
||||
salt: string;
|
||||
difficulty: number;
|
||||
}
|
||||
|
||||
interface WorkerChallengeLeadingZeroesSolveRequest extends ChallengeLeadingZeroesSolveRequest {
|
||||
type: WorkerMessageType.Challenge;
|
||||
}
|
||||
|
||||
interface ChallengeTargetNumberSolveRequest {
|
||||
strategy: ChallengeStrategy.TargetNumber;
|
||||
target: string;
|
||||
salt: string;
|
||||
}
|
||||
|
||||
interface WorkerChallengeTargetNumberSolveRequest extends ChallengeTargetNumberSolveRequest {
|
||||
type: WorkerMessageType.Challenge;
|
||||
}
|
||||
|
||||
export type ChallengeSolveRequest = ChallengeLeadingZeroesSolveRequest | ChallengeTargetNumberSolveRequest;
|
||||
type WorkerChallengeSolveRequest = WorkerChallengeLeadingZeroesSolveRequest | WorkerChallengeTargetNumberSolveRequest;
|
||||
|
||||
export type WorkerRequest = WorkerInitRequest | WorkerChallengeSolveRequest;
|
||||
|
||||
export enum WorkerResponseType {
|
||||
Error = "error",
|
||||
InitOk = "init_ok",
|
||||
Solution = "solution",
|
||||
}
|
||||
|
||||
interface ErrorMessageResponse {
|
||||
type: WorkerResponseType.Error;
|
||||
error: string;
|
||||
}
|
||||
|
||||
interface SolutionMessageResponse {
|
||||
type: WorkerResponseType.Solution;
|
||||
nonce: string;
|
||||
}
|
||||
|
||||
interface InitOkMessageResponse {
|
||||
type: WorkerResponseType.InitOk;
|
||||
}
|
||||
|
||||
export type SolutionMessage = ErrorMessageResponse | SolutionMessageResponse | InitOkMessageResponse;
|
||||
1
packages/widget/src/vite-env.d.ts
vendored
Normal file
1
packages/widget/src/vite-env.d.ts
vendored
Normal file
@@ -0,0 +1 @@
|
||||
/// <reference types="vite/client" />
|
||||
Reference in New Issue
Block a user