refactor: avoid leaking fetch internals by introducing TimeoutError

src/error/TimeoutError.ts

@@ -0,0 +1 @@
+export class TimeoutError extends Error {}

src/error/index.ts

@@ -3,3 +3,4 @@ export * from './HttpError';
 export * from './NotFoundError';
 export * from './QueueIsFullError';
 export * from './TooManyRequestsError';
+export * from './TimeoutError';

src/types.ts

@@ -1,7 +1,5 @@
 import { Manifest, ManifestConfig } from 'stremio-addon-sdk';
 
-export const TIMEOUT = 'timeout';
-
 export interface Context {
   id: string;
   ip: string;

src/utils/Fetcher.test.ts

@@ -2,7 +2,7 @@ import winston from 'winston';
 import fetchMock from 'fetch-mock';
 import { Fetcher } from './Fetcher';
 import { Context } from '../types';
-import { BlockedError, HttpError, NotFoundError, QueueIsFullError, TooManyRequestsError } from '../error';
+import { BlockedError, HttpError, NotFoundError, QueueIsFullError, TimeoutError, TooManyRequestsError } from '../error';
 fetchMock.mockGlobal();
 
 const fetcher = new Fetcher(winston.createLogger({ transports: [new winston.transports.Console({ level: 'nope' })] }));
@@ -182,7 +182,7 @@ describe('fetch', () => {
   test('times out', async () => {
     fetchMock.get('https://some-timeout-url.test/', 200, { delay: 20 });
 
-    await expect(fetcher.text(ctx, new URL('https://some-timeout-url.test/'), { timeout: 10 })).rejects.toBeInstanceOf(DOMException);
+    await expect(fetcher.text(ctx, new URL('https://some-timeout-url.test/'), { timeout: 10 })).rejects.toBeInstanceOf(TimeoutError);
   });
 
   test('queues requests and throws if queue is full', async () => {

src/utils/Fetcher.ts

@@ -3,8 +3,8 @@ import TTLCache from '@isaacs/ttlcache';
 import winston from 'winston';
 import { Semaphore, SemaphoreInterface, withTimeout } from 'async-mutex';
 import { Cookie, CookieJar } from 'tough-cookie';
-import { BlockedReason, Context, TIMEOUT } from '../types';
-import { BlockedError, HttpError, NotFoundError, QueueIsFullError, TooManyRequestsError } from '../error';
+import { BlockedReason, Context } from '../types';
+import { BlockedError, HttpError, NotFoundError, QueueIsFullError, TimeoutError, TooManyRequestsError } from '../error';
 import { clearTimeout } from 'node:timers';
 import { envGet } from './env';
 
@@ -229,11 +229,17 @@ export class Fetcher {
     }
 
     const controller = new AbortController();
-    const timer = setTimeout(() => controller.abort(TIMEOUT), init?.timeout ?? this.DEFAULT_TIMEOUT);
+    const timer = setTimeout(() => controller.abort(), init?.timeout ?? this.DEFAULT_TIMEOUT);
 
     let response;
     try {
       response = await fetch(url, { ...init, keepalive: true, signal: controller.signal });
+    } catch (error) {
+      if (error instanceof DOMException && error.name === 'AbortError') {
+        throw new TimeoutError();
+      }
+
+      throw error;
     } finally {
       clearTimeout(timer);
     }

src/utils/StreamResolver.test.ts

@@ -3,8 +3,8 @@ import winston from 'winston';
 import { createExtractors, Extractor, ExtractorRegistry } from '../extractor';
 import { StreamResolver } from './StreamResolver';
 import { Source, SourceResult, MeineCloud, MostraGuarda } from '../source';
-import { BlockedReason, Context, CountryCode, TIMEOUT, UrlResult } from '../types';
-import { BlockedError, HttpError, NotFoundError, QueueIsFullError, TooManyRequestsError } from '../error';
+import { BlockedReason, Context, CountryCode, UrlResult } from '../types';
+import { BlockedError, HttpError, NotFoundError, QueueIsFullError, TimeoutError, TooManyRequestsError } from '../error';
 import { ImdbId } from './id';
 import { FetcherMock } from './FetcherMock';
 
@@ -128,7 +128,7 @@ describe('resolve', () => {
           {
             url: new URL('https://example2.com'),
             isExternal: true,
-            error: TIMEOUT,
+            error: new TimeoutError(),
             label: 'hoster.com',
             sourceId: '',
             meta: {

src/utils/StreamResolver.ts

@@ -1,9 +1,9 @@
 import { ContentType, Stream } from 'stremio-addon-sdk';
 import winston from 'winston';
 import bytes from 'bytes';
-import { Context, TIMEOUT, UrlResult } from '../types';
+import { Context, UrlResult } from '../types';
 import { Source } from '../source';
-import { BlockedError, HttpError, NotFoundError, QueueIsFullError, TooManyRequestsError } from '../error';
+import { BlockedError, HttpError, NotFoundError, QueueIsFullError, TimeoutError, TooManyRequestsError } from '../error';
 import { flagFromCountryCode, languageFromCountryCode } from './language';
 import { envGetAppName } from './env';
 import { Id } from './id';
@@ -169,7 +169,7 @@ export class StreamResolver {
       return '🚦 Request was rate-limited. Please try again later or consider self-hosting.';
     }
 
-    if (error === TIMEOUT) {
+    if (error instanceof TimeoutError) {
       this.logger.warn(`${source}: Request timed out.`, ctx);
 
       return '🐢 Request timed out.';