From 28be571d61c447349906b325f20b5ed230e80c86 Mon Sep 17 00:00:00 2001
From: Alexander Adam <alexander.adam@vade.io>
Date: Sat, 16 May 2026 19:08:54 +0100
Subject: [PATCH] back off bulk metadata when API fails

getMetadataFor runs on every UI poll. for each uncached track in
the playlist we collected ids and called the data api. when the
call failed (bad key, quota, private video, network blip, whatever)
nothing was cached, so the next poll did the same thing again. a
long playlist turns this into a request storm that drags the whole
server down.

cache a tiny fail marker per id. 5 min for hard errors, 1 day for
ids the api never returns (most likely deleted or private). next
poll skips them so we stop hammering.
---
 plugin/ProtocolHandler.pm | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/plugin/ProtocolHandler.pm b/plugin/ProtocolHandler.pm
index 15ac0e0..356a65c 100644
--- a/plugin/ProtocolHandler.pm
+++ b/plugin/ProtocolHandler.pm
@@ -1156,7 +1156,8 @@ sub getMetadataFor {
 			if ( $trackURL =~ m{youtube:/*(.+)} ) {
 				my $trackId = $class->getId($trackURL);
 
-				if ( $trackId && !$cache->get("yt:meta-$trackId") ) {
+				# skip ids we already gave up on, dont hammer the api
+				if ( $trackId && !$cache->get("yt:meta-$trackId") && !$cache->get("yt:meta-fail-$trackId") ) {
 					push @need, $trackId;
 				} elsif (!$trackId) {
 					$log->warn("No id found: $trackURL");
@@ -1170,7 +1171,7 @@ sub getMetadataFor {
 		if (scalar @need && !$abort) {
 			my $list = join( ',', @need );
 			main::INFOLOG && $log->is_info && $log->info( "Need to fetch metadata for: $list");
-			_getBulkMetadata($client, $pageCall, $list);
+			_getBulkMetadata($client, $pageCall, $list, \@need);
 		} else {
 			$client->master->pluginData(fetchingYTMeta => 0);
 			unless ($abort) {
@@ -1198,13 +1199,19 @@ sub getMetadataFor {
 }
 
 sub _getBulkMetadata {
-	my ($client, $cb, $ids) = @_;
+	my ($client, $cb, $ids, $requestedIds) = @_;
 
 	Plugins::YouTube::API->getVideoDetails( sub {
 		my $result = shift;
 
 		if ( !$result || $result->{error} || !$result->{pageInfo}->{totalResults} || !scalar @{$result->{items}} ) {
 			$log->error($result->{error} || 'Failed to grab track information');
+			# mark these failed for 5 min. enough to break the request storm,
+			# short enough that a fixed api key or transient blip recovers
+			# soon after.
+			if ($requestedIds) {
+				$cache->set("yt:meta-fail-$_", 1, 300) for @$requestedIds;
+			}
 			$cb->(1) if defined $cb;
 			return;
 		}
@@ -1241,6 +1248,15 @@ sub _getBulkMetadata {
 			$cache->set("yt:meta-" . $item->{id}, $meta, 86400);
 		}
 
+		# ids we asked for but didnt get back are usually deleted or private.
+		# cache as failed for a day so the UI poll stops asking.
+		if ($requestedIds) {
+			my %got = map { $_->{id} => 1 } @{$result->{items}};
+			for my $id (@$requestedIds) {
+				$cache->set("yt:meta-fail-$id", 1, 86400) unless $got{$id};
+			}
+		}
+
 		$cb->() if defined $cb;
 
 	}, $ids);