feat: @discordjs/ws (#8260)

Co-authored-by: Parbez <imranbarbhuiya.fsd@gmail.com>

packages/ws/src/utils/IdentifyThrottler.ts

@@ -0,0 +1,29 @@
+import { setTimeout as sleep } from 'node:timers/promises';
+import type { WebSocketManager } from '../ws/WebSocketManager';
+
+export class IdentifyThrottler {
+	private identifyState = {
+		remaining: 0,
+		resetsAt: Infinity,
+	};
+
+	public constructor(private readonly manager: WebSocketManager) {}
+
+	public async waitForIdentify(): Promise<void> {
+		if (this.identifyState.remaining <= 0) {
+			const diff = this.identifyState.resetsAt - Date.now();
+			if (diff <= 5_000) {
+				const time = diff + Math.random() * 1_500;
+				await sleep(time);
+			}
+
+			const info = await this.manager.fetchGatewayInformation();
+			this.identifyState = {
+				remaining: info.session_start_limit.max_concurrency,
+				resetsAt: Date.now() + 5_000,
+			};
+		}
+
+		this.identifyState.remaining--;
+	}
+}

packages/ws/src/utils/constants.ts

@@ -0,0 +1,68 @@
+import { readFileSync } from 'node:fs';
+import { join } from 'node:path';
+import { Collection } from '@discordjs/collection';
+import { APIVersion, GatewayOpcodes } from 'discord-api-types/v10';
+import { lazy } from './utils';
+import type { OptionalWebSocketManagerOptions, SessionInfo } from '../ws/WebSocketManager';
+
+/**
+ * Valid encoding types
+ */
+export enum Encoding {
+	JSON = 'json',
+}
+
+/**
+ * Valid compression methods
+ */
+export enum CompressionMethod {
+	ZlibStream = 'zlib-stream',
+}
+
+const packageJson = readFileSync(join(__dirname, '..', '..', 'package.json'), 'utf8');
+// eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+const Package = JSON.parse(packageJson);
+
+// eslint-disable-next-line @typescript-eslint/restrict-template-expressions, @typescript-eslint/no-unsafe-member-access
+export const DefaultDeviceProperty = `@discordjs/ws ${Package.version}`;
+
+const getDefaultSessionStore = lazy(() => new Collection<number, SessionInfo | null>());
+
+/**
+ * Default options used by the manager
+ */
+export const DefaultWebSocketManagerOptions: OptionalWebSocketManagerOptions = {
+	shardCount: null,
+	shardIds: null,
+	largeThreshold: null,
+	initialPresence: null,
+	identifyProperties: {
+		browser: DefaultDeviceProperty,
+		device: DefaultDeviceProperty,
+		os: process.platform,
+	},
+	version: APIVersion,
+	encoding: Encoding.JSON,
+	compression: null,
+	retrieveSessionInfo(shardId) {
+		const store = getDefaultSessionStore();
+		return store.get(shardId) ?? null;
+	},
+	updateSessionInfo(shardId: number, info: SessionInfo | null) {
+		const store = getDefaultSessionStore();
+		if (info) {
+			store.set(shardId, info);
+		} else {
+			store.delete(shardId);
+		}
+	},
+	handshakeTimeout: 30_000,
+	helloTimeout: 60_000,
+	readyTimeout: 15_000,
+};
+
+export const ImportantGatewayOpcodes = new Set([
+	GatewayOpcodes.Heartbeat,
+	GatewayOpcodes.Identify,
+	GatewayOpcodes.Resume,
+]);

packages/ws/src/utils/utils.ts

@@ -0,0 +1,20 @@
+import type { ShardRange } from '../ws/WebSocketManager';
+
+export type Awaitable<T> = T | Promise<T>;
+
+/**
+ * Yields the numbers in the given range as an array
+ * @example
+ * range({ start: 3, end: 5 }); // [3, 4, 5]
+ */
+export function range({ start, end }: ShardRange): number[] {
+	return Array.from({ length: end - start + 1 }, (_, i) => i + start);
+}
+
+/**
+ * Lazily evaluate a callback, storing its result
+ */
+export function lazy<T>(cb: () => T): () => T {
+	let defaultValue: T;
+	return () => (defaultValue ??= cb());
+}