Update bundled yt-dlp and report source failures in chat

The image shipped a year-old yt-dlp, which YouTube now rejects with
"The page needs to be reloaded". Bumped to 2026.08.19 and documented
rebuilding as the standard fix, including how to pass a newer tag
without waiting for a repository update.

A downloader dying mid-stream also looked exactly like a very short
track: ffmpeg saw EOF, the player advanced, and the channel only got
"queue finished". The failure reason now reaches the chat.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Dockerfile

@@ -28,7 +28,10 @@ ENV HOME=/tmp
 WORKDIR /app
 
 # yt-dlp_linux is a self-contained binary, so no Python runtime is needed.
-ARG YTDLP_VERSION=2025.08.20
+# YouTube breaks extractors regularly, so keep this current: rebuilding with
+# --build-arg YTDLP_VERSION=<tag> (or bumping this default) is the usual fix for
+# "The page needs to be reloaded" and similar extraction errors.
+ARG YTDLP_VERSION=2026.08.19
 RUN apt-get update \
     && apt-get install -y --no-install-recommends ca-certificates curl \
     && curl -fsSL "https://github.com/yt-dlp/yt-dlp/releases/download/${YTDLP_VERSION}/yt-dlp_linux" -o /usr/local/bin/yt-dlp \

README.md

@@ -188,6 +188,24 @@ cd /opt/stoat-mbot && docker compose up -d --build && docker compose logs -f
 - `YTDLP_COOKIES` — путь к `cookies.txt`, см. раздел ниже.
 - `YTDLP_EXTRACTOR_ARGS` — дополнительные `--extractor-args` через `;`.
 
+## Обновление yt-dlp
+
+YouTube регулярно ломает экстракторы, и симптом всегда один: трек находится, но не играет, а в
+логах — `ERROR: [youtube] ...: The page needs to be reloaded` или подобное. Лечится обновлением
+yt-dlp: версия зашита в [Dockerfile](Dockerfile) как `ARG YTDLP_VERSION`.
+
+```bash
+cd /opt/stoat-mbot && git pull && docker compose up -d --build
+```
+
+Если свежая версия вышла, а обновления репозитория ещё нет — можно указать её сразу:
+
+```bash
+docker compose build --build-arg YTDLP_VERSION=$(date +%Y.%m.%d) && docker compose up -d
+```
+
+Актуальный тег — на [странице релизов yt-dlp](https://github.com/yt-dlp/yt-dlp/releases).
+
 ## Учётка YouTube (cookies)
 
 Логин и пароль для YouTube yt-dlp не поддерживает — единственный рабочий способ авторизоваться

src/core/player.ts

@@ -276,6 +276,14 @@ export class GuildPlayer extends EventEmitter<GuildPlayerEvents> {
       // stop() rebuilds the volume transformer, so volume is applied per track.
       media.setVolume(this.volume / 100);
       this.startTicker();
+
+      // A downloader that dies mid-stream just looks like a very short track, so
+      // say why instead of silently moving on.
+      void input.failure?.then((reason) => {
+        if (!reason || this.current?.id !== track.id) return;
+        this.log.warn({ reason, track: track.title }, "source failed while streaming");
+        this.notify(`⚠️ **${track.title}** — источник отдал ошибку: ${reason}`);
+      });
     } catch (err) {
       this.log.warn({ err, track: track.title }, "playback failed");
       const message = err instanceof UserFacingError ? err.message : "неизвестная ошибка";

src/sources/index.ts

@@ -110,6 +110,8 @@ export interface PlaybackInput {
   input: string | Readable;
   inputOptions: string[];
   cleanup(): void;
+  /** Resolves with a reason if the downloader died on its own, for reporting. */
+  failure?: Promise<string | null>;
 }
 
 const HTTP_RESILIENCE = [
@@ -139,5 +141,10 @@ export async function openPlayback(track: Track, seekSeconds = 0): Promise<Playb
   }
 
   const proc = ytdlp.openAudioStream(track.url);
-  return { input: proc.stream, inputOptions: [], cleanup: () => proc.kill() };
+  return {
+    input: proc.stream,
+    inputOptions: [],
+    cleanup: () => proc.kill(),
+    failure: proc.failure,
+  };
 }

src/sources/ytdlp.ts

@@ -209,6 +209,8 @@ export async function resolveStreamUrl(pageUrl: string): Promise<string> {
 export interface AudioProcess {
   stream: Readable;
   kill(): void;
+  /** Resolves with a reason when the download fails, or null when it was fine. */
+  failure: Promise<string | null>;
 }
 
 /** Spawns yt-dlp writing the best audio to stdout, for piping straight into ffmpeg. */
@@ -220,19 +222,29 @@ export function openAudioStream(pageUrl: string): AudioProcess {
   );
 
   let stderr = "";
+  let killed = false;
   child.stderr.setEncoding("utf8");
   child.stderr.on("data", (chunk: string) => {
     stderr = (stderr + chunk).slice(-2000);
   });
+
+  const failure = new Promise<string | null>((resolve) => {
     child.on("close", (code) => {
-    if (code !== 0 && code !== null && stderr.trim()) {
-      log.warn({ code, stderr: stderr.slice(0, 500) }, "yt-dlp stream exited with error");
+      if (killed || code === 0 || code === null) {
+        resolve(null);
+        return;
       }
+      log.warn({ code, stderr: stderr.slice(0, 500) }, "yt-dlp stream exited with error");
+      resolve(firstUsefulError(stderr));
+    });
+    child.on("error", (err: Error) => resolve(err.message));
   });
 
   return {
     stream: child.stdout,
+    failure,
     kill: () => {
+      killed = true;
       if (child.exitCode === null) child.kill("SIGKILL");
     },
   };