From 9318998f9a1eb9b87aab4b3dcf4cc8572bb01776 Mon Sep 17 00:00:00 2001
From: Kevin Heneveld <1192102+kevinheneveld@users.noreply.github.com>
Date: Tue, 14 Jul 2026 10:53:40 -0800
Subject: [PATCH] fix(metadata): treat Audible's empty product stub as no
 answer so the provider chain can continue
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An ASIN missing from Audible's catalog resolves to a non-null but EMPTY
AudibleBookResponse (no title, no fields — the catalog API returns a
product node with every attribute null). The provider loop took that
shell as a successful answer: the caller received junk metadata
('source: Audible' with nothing in it) and every later source in the
chain (Audnexus, anything added in future) was silently skipped.

Live case: an Amazon-exclusive edition whose ASIN returns the empty
stub from all ten regional Audible catalogs — 'fill missing from
online' reported success while filling nothing. A titleless response
is now treated as no answer and the chain falls through.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 .../Metadata/Core/AudiobookMetadataService.cs        | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/listenarr.application/Metadata/Core/AudiobookMetadataService.cs b/listenarr.application/Metadata/Core/AudiobookMetadataService.cs
index 3181f7e1f..97bf0310b 100644
--- a/listenarr.application/Metadata/Core/AudiobookMetadataService.cs
+++ b/listenarr.application/Metadata/Core/AudiobookMetadataService.cs
@@ -115,6 +115,18 @@ public AudiobookMetadataService(
                         continue;
                     }
 
+                    // An ASIN missing from Audible's catalog comes back as a
+                    // non-null but EMPTY product stub (no title, no fields).
+                    // Treating that as an answer both returns junk to the
+                    // caller and blocks every later source in the chain.
+                    if (result is AudibleBookResponse shell && string.IsNullOrWhiteSpace(shell.Title))
+                    {
+                        _logger.LogInformation(
+                            "{SourceName} returned an empty product stub for ASIN {Asin}; treating as no answer",
+                            source.Name, asin);
+                        result = null;
+                    }
+
                     if (result != null)
                     {
                         _logger.LogInformation("Successfully fetched metadata from {SourceName} for ASIN: {Asin}", source.Name, asin);