Update cache naming

Use appropriate naming for files downloaded via yt-dlp.

src/video-types/youtube/clipper.ts

@@ -8,6 +8,7 @@ import {
 import { VIDEO_TYPE } from './common';
 import { constructDefaultDownloadArgs, getFileExtension } from './downloader';
 import { DownloaderFailedToStartError, DownloaderNotFoundError } from './errors';
+import {retrieveVideoId} from './url';
 
 export interface CreateClipperParams extends CreateBaseClipperParams {
   type: typeof VIDEO_TYPE;
@@ -24,7 +25,8 @@ export const createVideoClipper = (createClipperParams: Omit<CreateClipperParams
     createClipperParams.downloaderExecutablePath,
     clipVideoParams.url,
   );
-  const cacheFilename = `output.${fileExtension}`; // todo label this on the cache
+  const videoId = retrieveVideoId(clipVideoParams.url);
+  const cacheFilename = `output.${encodeURIComponent(videoId)}.${fileExtension}`;
   const downloadArgs = constructDefaultDownloadArgs(
     cacheFilename,
     clipVideoParams.url,

src/video-types/youtube/downloader.ts

@@ -51,6 +51,12 @@ export const getFileExtension = (downloaderExecutablePath: string, url: string)
     throw result.error;
   }
 
+  const errorMessage = result.stderr.toString('utf-8').trim();
+
+  if (errorMessage.length > 0) {
+    throw new Error(errorMessage);
+  }
+
   return result.stdout.toString('utf-8').trim();
 };
 

src/video-types/youtube/errors.ts

@@ -1,3 +1,5 @@
 export class DownloaderNotFoundError extends Error {}
 
 export class DownloaderFailedToStartError extends Error {}
+
+export class InvalidVideoIdError extends Error {}

src/video-types/youtube/url.ts

@@ -0,0 +1,19 @@
+import { InvalidVideoIdError } from './errors';
+
+const STANDARD_YOUTUBE_VIDEO_ID_LENGTH = 11 as const;
+
+export const RE_YOUTUBE = /^.*(?:(?:youtu\.be\/|v\/|vi\/|u\/\w\/|embed\/)|(?:(?:watch)?\?v?:i?=|&v?:i?=))([^#&?]*).*/im;
+
+export const retrieveVideoId = (videoId: string): string => {
+  if (typeof (videoId as unknown) !== 'string') {
+    throw new InvalidVideoIdError('The video ID must be a string.');
+  }
+  if (videoId.length === STANDARD_YOUTUBE_VIDEO_ID_LENGTH) {
+    return videoId;
+  }
+  const matchId = videoId.match(RE_YOUTUBE);
+  if (matchId && matchId.length > 1) {
+    return matchId[1];
+  }
+  throw new InvalidVideoIdError('Impossible to retrieve Youtube video ID.');
+};