Custom oauth lib

The package used is deprecated. And I want to be able to debug oauth errors better.

src/utils/index.ts

@@ -16,6 +16,7 @@ export * from './message-utils';
 export * from './ms-to-human';
 export * from './name-sync';
 export * from './note-utils';
+export * from './oauth2';
 export * from './record-utils';
 export * from './refresh-commands';
 export * from './search-regex';

src/utils/oauth2.ts

@@ -0,0 +1,124 @@
+type ClientOptions = {
+  clientId: string
+  clientSecret: string
+  clientToken: string
+  redirectUri: string
+  credentials: string
+};
+
+type GenerateUrlParameters = {
+  state: string
+  scope: string[]
+  type: 'code' | 'token'
+};
+
+type TokenResponse = {
+  access_token: string
+  token_type: string
+  expires_in: number
+  refresh_token: string
+  scope: string
+}
+
+type DiscordUser = {
+  id: string
+  username: string
+  // bunch of other stuff we don't use
+}
+
+type AddMemberOptions = {
+  accessToken: string
+  botToken?: string
+  guildId: string
+  userId: string
+  nickname?: string
+}
+
+const OAUTH_BASE_URL = 'https://discord.com/oauth2';
+const OAUTH_API_BASE_URL = 'https://discord.com/api/oauth2';
+const API_BASE_URL = 'https://discord.com/api';
+
+export class DiscordOAuth2 {
+  constructor(private options: ClientOptions) { }
+
+  generateOauth2Url(options: GenerateUrlParameters) {
+    const url = new URL(`${OAUTH_BASE_URL}/authorize`);
+
+    const params = new URLSearchParams({
+      client_id: this.options.clientId,
+      response_type: options.type,
+      redirect_uri: this.options.redirectUri,
+      scope: options.scope.join('+'),
+      state: options.state
+    });
+
+    url.search = params.toString();
+
+    return url.toString();
+  }
+
+  async getAccessToken(code: string, scope: string[]): Promise<TokenResponse> {
+    const res = await fetch(`${OAUTH_API_BASE_URL}/token`, {
+      method: 'POST',
+      body: new URLSearchParams({
+        client_id: this.options.clientId,
+        client_secret: this.options.clientSecret,
+        code,
+        grant_type: 'authorization_code',
+        redirect_uri: this.options.redirectUri,
+        scope: scope.join(' ')
+      }).toString(),
+      headers: {
+        'Content-Type': 'application/x-www-form-urlencoded',
+        Accept: 'application/json'
+      }
+    });
+
+    const data = await res.json();
+    return data as TokenResponse;
+  }
+
+  async getUser(accessToken: string): Promise<DiscordUser> {
+    const res = await fetch(`${API_BASE_URL}/users/@me`, {
+      headers: {
+        Authorization: `Bearer ${accessToken}`,
+        Accept: 'application/json'
+      }
+    });
+
+    return await res.json() as DiscordUser;
+  }
+
+  async addMember(options: AddMemberOptions) {
+    const res = await fetch(`${API_BASE_URL}/guilds/${options.guildId}/members/${options.userId}`, {
+      method: 'PUT',
+      body: JSON.stringify({
+        nick: options.nickname,
+        access_token: options.accessToken
+      }),
+      headers: {
+        'Content-Type': 'application/json',
+        Authorization: `Bot ${this.options.clientToken}`,
+        Accept: 'application/json'
+      }
+    });
+
+    return await res.json();
+  }
+
+  async revokeToken(token: string) {
+    const res = await fetch(`${OAUTH_API_BASE_URL}/token/revoke`, {
+      method: 'POST',
+      body: new URLSearchParams({
+        token
+      }).toString(),
+      headers: {
+        'Content-Type': 'application/x-www-form-urlencoded',
+        Authorization: `Basic ${this.options.credentials}`,
+        Accept: 'application/json'
+      }
+    });
+
+    return await res.json();
+  }
+}

src/webserver/index.ts

@@ -1,5 +1,4 @@
 import express, { Request, Response } from 'express';
-import DiscordOAuth2 from 'discord-oauth2';
 import { config } from '../config';
 import { Database } from '../shared/Database';
 import crypto from 'crypto';
@@ -11,7 +10,7 @@ import { Client } from 'discord.js';
 import bodyParser from 'body-parser';
 import { fixPings, removeIssueLinks } from '../utils/github-user-utils';
 import { logDebug } from '../utils/debug-utils';
-import { AltData, comprehensiveAltLookupFromE621 } from '../utils';
+import { AltData, comprehensiveAltLookupFromE621, DiscordOAuth2 } from '../utils';
 
 declare module 'express-session' {
   interface SessionData {
@@ -25,12 +24,15 @@ const GITHUB_REPO_ID = 169334303;
 const DEV_BASE_URL = `http://localhost:${config.PORT}`;
 const PROD_BASE_URL = 'https://discord.e621.net';
 
+const OAUTH_SCOPES = ['identify', 'guilds.join'];
+
 const PAGE_TEMPLATE = fs.readFileSync(path.join(__dirname, 'templates', 'page.html'), { encoding: 'utf-8' });
 
 const oauth = new DiscordOAuth2({
   clientId: config.DISCORD_CLIENT_ID!,
   clientSecret: config.DISCORD_CLIENT_SECRET!,
   redirectUri: `${config.DEV_MODE ? DEV_BASE_URL : PROD_BASE_URL}/callback`,
+  clientToken: config.DISCORD_TOKEN!,
   credentials: Buffer.from(`${config.DISCORD_CLIENT_ID!}:${config.DISCORD_CLIENT_SECRET!}`).toString('base64')
 });
 
@@ -48,11 +50,7 @@ async function joinGuild(code: string, userId: string, username: string): Promis
 
     const id = Number(userId);
 
-    tokenResponse = await oauth.tokenRequest({
-      code,
-      scope: 'identify guilds.join',
-      grantType: 'authorization_code'
-    });
+    tokenResponse = await oauth.getAccessToken(code, OAUTH_SCOPES);
 
     const user = await oauth.getUser(tokenResponse.access_token);
 
@@ -64,7 +62,6 @@ async function joinGuild(code: string, userId: string, username: string): Promis
 
     await oauth.addMember({
       accessToken: tokenResponse.access_token,
-      botToken: config.DISCORD_TOKEN!,
       guildId: config.DISCORD_GUILD_ID!,
       userId: user.id,
       nickname: username
@@ -103,6 +100,12 @@ async function handleInitial(req: Request, res: Response): Promise<any> {
 
   const oauthState = crypto.randomBytes(16).toString('hex');
 
+  const oauthUrl = await oauth.generateOauth2Url({
+    state: oauthState,
+    scope: OAUTH_SCOPES,
+    type: 'code'
+  });
+
   req.session.username = username as string;
   req.session.userId = user_id as string;
   req.session.oauthState = oauthState;
@@ -114,10 +117,7 @@ async function handleInitial(req: Request, res: Response): Promise<any> {
       return sendInteralServerError(res);
     }
 
-    res.redirect(oauth.generateAuthUrl({
-      state: oauthState,
-      scope: ['identify', 'guilds.join']
-    }));
+    res.redirect(oauthUrl);
   });
 }
 
@@ -146,7 +146,7 @@ async function handleCallback(req: Request, res: Response): Promise<any> {
     const response = await joinGuild(code, userId, username);
     if (response == JoinResponse.Error) {
       console.error(`Error joining user: ${username} (${userId})`);
-      return sendInteralServerError(res, 'Unable to join user to guild.');
+      return sendInteralServerError(res, 'Unable to join user to guild. Retry later. If issue persists, please contact staff.');
     } else if (response == JoinResponse.Banned) {
       return sendForbidden(res, 'User is banned.');
     }