feat(gateway): wip: Connect to the Discord Gateway

package.json

@@ -37,6 +37,7 @@
 	"dependencies": {
 		"@sapphire/async-queue": "^1.1.4",
 		"abort-controller": "^3.0.0",
+		"fast-zlib": "^2.0.1",
 		"form-data": "^4.0.0",
 		"lodash": "^4.17.21",
 		"node-fetch": "^2.6.1",
@@ -89,8 +90,7 @@
 	},
 	"optionalDependencies": {
 		"bufferutil": "^4.0.3",
-		"utf-8-validate": "^5.0.5",
-		"zlib-sync": "^0.1.7"
+		"utf-8-validate": "^5.0.5"
 	},
 	"lint-staged": {
 		"src/**/*": [

src/api/apiHandler.ts

@@ -10,7 +10,6 @@ import type { Client } from '../client/client';
 import type { IMakeRequestOptions, IRouteIdentifier } from '../utils/types';
 
 function calculateReset(reset: number, resetAfter: number, serverDate: number): number {
-	// Use direct reset time when available, server date becomes irrelevant in this case
 	if (resetAfter) {
 		return Date.now() + Number(resetAfter) * 1000;
 	}
@@ -21,7 +20,6 @@ function getAPIOffset(serverDate: number): number {
 	return new Date(serverDate).getTime() - Date.now();
 }
 
-
 export class ApiHandler {
 	public client: Client;
 	public hash: string;
@@ -35,7 +33,7 @@ export class ApiHandler {
 
 	private _token: string;
 
-	public constructor(client: Client, manager: ApiManager, token: string, hash: string, majorParameter: string) {
+	public constructor(client: Client, token: string, manager: ApiManager, hash: string, majorParameter: string) {
 		this.client = client;
 		this._token = token;
 

src/api/apiManager.ts

@@ -32,7 +32,7 @@ export class ApiManager {
 		let queue = this.queues.get(`${hash}:${routeId.majorParameter}`);
 
 		if (!queue) {
-			const apiHandler = new ApiHandler(this.client, this, this._token, hash, routeId.majorParameter);
+			const apiHandler = new ApiHandler(this.client, this._token, this, hash, routeId.majorParameter);
 			this.queues.set(apiHandler.id, apiHandler);
 
 			queue = this.queues.get(`${hash}:${routeId.majorParameter}`);

src/client/client.ts

@@ -1,20 +1,30 @@
 import _ from 'lodash';
+import EventEmitter from 'events';
 
 import { ApiHelper } from '../api/apiHelper';
+import { GatewayClient } from '../gateway/gatewayClient';
 import { defaults } from '../utils/defaults';
 
 import type { DeepRequired, IClientOptions } from '../utils/types';
 
-export class Client {
+export class Client extends EventEmitter {
 	public api: ApiHelper;
-	public options: DeepRequired<IClientOptions>;
+	public readonly options: DeepRequired<IClientOptions>;
+	public ws: GatewayClient;
 
 	private _token: string;
 
 	public constructor(token: string, options: IClientOptions = {}) {
+		super();
+
 		this.options = _.merge(defaults.clientOptions, options as DeepRequired<IClientOptions>);
 		this._token = token;
 
 		this.api = new ApiHelper(this, this._token);
+		this.ws = new GatewayClient(this);
+	}
+
+	public async login(): Promise<void> {
+		await this.ws.connect();
 	}
 }

src/gateway/gatewayClient.ts

@@ -0,0 +1,44 @@
+import zlib from 'fast-zlib';
+import WebSocket from 'ws';
+
+import type { Client } from '../client/client';
+import type { IGatewayMessage } from '../utils/types';
+
+export class GatewayClient {
+	public client: Client;
+	public connection: WebSocket | null;
+	public deflate: zlib.Deflate;
+	public inflate: zlib.Inflate;
+
+	private _sequence: number;
+
+	public constructor(client: Client) {
+		this.client = client;
+
+		this.connection = null;
+		this.deflate = new zlib.Deflate();
+		this.inflate = new zlib.Inflate();
+
+		this._sequence = 0;
+	}
+
+	public async close(): Promise<void> {
+		if (!this.connection) throw new Error('You are not connected to the Discord WebSocket Gateway!');
+
+		this.connection.close(1000);
+	}
+
+	public async connect(): Promise<void> {
+		if (this.connection) throw new Error('You are already connected to the Discord WebSocket Gateway!');
+
+		this.connection = new WebSocket(
+			`${this.client.options.ws.url}/?v=${this.client.options.ws.version}${this.client.options.ws.compression ? '&compress=zlib-stream' : ''}&encoding=${this.client.options.ws.encoding}`,
+		);
+
+		this.connection.on('message', async (msg: Buffer | string) => {
+			let parsedMessage: IGatewayMessage<null>;
+
+			if (this.client.options.ws.compression) parsedMessage = this.inflate.process(msg);
+		});
+	}
+}

src/utils/defaults.ts

@@ -10,5 +10,11 @@ export const defaults: IDefaultOptions = {
 			url: 'https://discord.com/api',
 			version: 9,
 		},
+		ws: {
+			compression: true,
+			encoding: 'json',
+			url: 'wss://gateway.discord.gg',
+			version: 9,
+		},
 	},
 };

src/utils/types.ts

@@ -10,6 +10,7 @@ export interface IApiClientOptions {
 
 export interface IClientOptions {
 	api?: IApiClientOptions;
+	ws?: IWebSocketClientOptions;
 }
 
 export interface IDefaultOptions {
@@ -55,6 +56,13 @@ export interface IRouteIdentifier {
 	route: string;
 }
 
+export interface IWebSocketClientOptions {
+	compression?: boolean;
+	encoding?: 'json';
+	url?: string;
+	version?: number;
+}
+
 // Api Rest Request Interfaces
 // TODO: Add message components
 export interface IApiCreateMessage {
@@ -76,6 +84,14 @@ export interface IApiCreateMessage {
 	tts?: boolean;
 }
 
+// WebSocket Gateway Message Interfaces
+export interface IGatewayMessage<T> {
+	d?: T;
+	op: number;
+	s?: number;
+	t?: string;
+}
+
 // Enums
 
 // Type Aliases

yarn.lock

@@ -569,6 +569,7 @@ __metadata:
     eslint-plugin-header: ^3.1.1
     eslint-plugin-import: ^2.23.4
     eslint-plugin-unicorn: ^34.0.1
+    fast-zlib: ^2.0.1
     form-data: ^4.0.0
     husky: ^7.0.0
     inquirer: ^8.1.1
@@ -587,14 +588,11 @@ __metadata:
     typescript: ^4.3.5
     utf-8-validate: ^5.0.5
     ws: ^7.5.2
-    zlib-sync: ^0.1.7
   dependenciesMeta:
     bufferutil:
       optional: true
     utf-8-validate:
       optional: true
-    zlib-sync:
-      optional: true
   languageName: unknown
   linkType: soft
 
@@ -3503,6 +3501,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"fast-zlib@npm:^2.0.1":
+  version: 2.0.1
+  resolution: "fast-zlib@npm:2.0.1"
+  checksum: 5019499b8aea5dea805117944cdcd4f7bf06b8d922690d4dca6384b5d6c0cc73b6e3c1488ab5c0b8add486617a2b6b2a0230f719be84362943a348c55f864a5a
+  languageName: node
+  linkType: hard
+
 "fastq@npm:^1.6.0":
   version: 1.11.1
   resolution: "fastq@npm:1.11.1"
@@ -5907,15 +5912,6 @@ fsevents@~2.3.2:
   languageName: node
   linkType: hard
 
-"nan@npm:^2.14.0":
-  version: 2.14.2
-  resolution: "nan@npm:2.14.2"
-  dependencies:
-    node-gyp: latest
-  checksum: 7a269139b66a7d37470effb7fb36a8de8cc3b5ffba6e40bb8e0545307911fe5ebf94797ec62f655ecde79c237d169899f8bd28256c66a32cbc8284faaf94c3f4
-  languageName: node
-  linkType: hard
-
 "nanoid@npm:3.1.23":
   version: 3.1.23
   resolution: "nanoid@npm:3.1.23"
@@ -8802,13 +8798,3 @@ typescript@^4.3.5:
   checksum: f77b3d8d00310def622123df93d4ee654fc6a0096182af8bd60679ddcdfb3474c56c6c7190817c84a2785648cdee9d721c0154eb45698c62176c322fb46fc700
   languageName: node
   linkType: hard
-
-"zlib-sync@npm:^0.1.7":
-  version: 0.1.7
-  resolution: "zlib-sync@npm:0.1.7"
-  dependencies:
-    nan: ^2.14.0
-    node-gyp: latest
-  checksum: 8f6ef7bf5726b41fefffa4509f5679872b425ef47227a59d8c787b32518db6220961262f78b0f6eb1dcd9b52cd71bc8213d4f061b8b56a9b7e82c345a548e6f4
-  languageName: node
-  linkType: hard