Fix: surface YouTube API errors instead of silently reporting no videos

bot/cogs/youtube_watcher.py

@@ -36,6 +36,7 @@
 import discord
 from discord import app_commands
 from discord.ext import commands, tasks
+from googleapiclient.errors import HttpError
 
 from utils.state import load_state, save_state
 from utils.youtube_api import YouTubeClient
@@ -221,6 +222,13 @@ async def youtubedigest(self, interaction: discord.Interaction) -> None:
                 f"✅ YouTube digest posted to <#{self.discord_channel_id}> ({len(videos)} video(s)).",
                 ephemeral=True,
             )
+        except HttpError as exc:
+            logger.error("YouTube API error during manual digest for %s: %s", interaction.user, exc)
+            await interaction.followup.send(
+                f"❌ YouTube API error (status {exc.status_code}): {exc.reason}\n"
+                "This is usually a quota issue or invalid API key — check the logs and your Google Cloud console.",
+                ephemeral=True,
+            )
         except Exception:
             logger.exception("Manual YouTube digest failed for %s.", interaction.user)
             await interaction.followup.send(

tests/test_youtube_api.py

@@ -1,6 +1,9 @@
 import unittest
 from datetime import datetime, timezone
 from unittest.mock import patch
+from unittest.mock import MagicMock
+
+from googleapiclient.errors import HttpError
 
 from utils.youtube_api import YouTubeClient
 
@@ -48,6 +51,31 @@ def videos(self):
 
 
 class YouTubeApiTests(unittest.TestCase):
+    def test_search_recent_propagates_http_error(self) -> None:
+        """HttpError from the API must propagate so callers can distinguish
+        a genuine empty result from an API failure (e.g. quota exceeded)."""
+        fake_resp = MagicMock()
+        fake_resp.status = 403
+        fake_resp.reason = "quotaExceeded"
+        error = HttpError(resp=fake_resp, content=b'{"error":{"message":"quotaExceeded"}}')
+
+        class _ErrorSearchResource:
+            def list(self, **kwargs):
+                raise error
+
+        class _ErrorService:
+            def search(self):
+                return _ErrorSearchResource()
+
+        client = YouTubeClient.__new__(YouTubeClient)
+        client._service = _ErrorService()
+
+        with self.assertRaises(HttpError):
+            client.search_recent(
+                channel_id="channel-id",
+                published_after=datetime(2026, 5, 1, tzinfo=timezone.utc),
+            )
+
     def test_search_recent_requires_timezone_aware_datetime(self) -> None:
         client = YouTubeClient.__new__(YouTubeClient)
         client._service = _FakeService()

utils/youtube_api.py

@@ -78,34 +78,27 @@ def search_recent(
         - ``thumbnail``   – URL of the high-quality thumbnail image
         - ``view_count``  – 0 (placeholder; populate with :meth:`get_video_statistics`)
 
-        Returns an empty list when the API call fails.
+        Raises :class:`googleapiclient.errors.HttpError` if the API call fails
+        so callers can distinguish a genuine empty result from an API error.
         """
         if published_after.tzinfo is None:
             raise ValueError(
                 "published_after must be a timezone-aware datetime (e.g. use timezone.utc)"
             )
 
         published_after_str = published_after.strftime("%Y-%m-%dT%H:%M:%SZ")
-        try:
-            response = (
-                self._service.search()
-                .list(
-                    part="snippet",
-                    channelId=channel_id,
-                    order="date",
-                    type="video",
-                    publishedAfter=published_after_str,
-                    maxResults=max_results,
-                )
-                .execute()
+        response = (
+            self._service.search()
+            .list(
+                part="snippet",
+                channelId=channel_id,
+                order="date",
+                type="video",
+                publishedAfter=published_after_str,
+                maxResults=max_results,
             )
-        except HttpError as exc:
-            logger.error(
-                "YouTube API search error (channel=%s): %s",
-                channel_id,
-                exc,
-            )
-            return []
+            .execute()
+        )
 
         videos: List[dict] = []
         for item in response.get("items", []):