From 5c2466832c0d2ea305bdc9d6f712bd88840a13b2 Mon Sep 17 00:00:00 2001
From: Jon Allured <jon@jonallured.com>
Date: Sun, 22 Dec 2024 12:53:20 -0700
Subject: [PATCH] Improve enhancer sad path

---
 app/models/book/enhancer.rb       |  7 +++++--
 spec/models/book/enhancer_spec.rb | 14 ++++++++++++++
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/app/models/book/enhancer.rb b/app/models/book/enhancer.rb
index c387167..f270ab1 100644
--- a/app/models/book/enhancer.rb
+++ b/app/models/book/enhancer.rb
@@ -5,11 +5,14 @@ def update_from_api
     api_data = OpenLibraryApi.get_book(book.isbn)
     return unless api_data
 
+    isbns = api_data["isbn_13"] || []
+
     attrs = {
-      isbn: api_data["isbn_13"].first,
+      isbn: isbns.first,
       pages: api_data["number_of_pages"],
       title: api_data["title"]
-    }
+    }.compact
+    return unless attrs.any?
 
     book.update!(attrs)
   end
diff --git a/spec/models/book/enhancer_spec.rb b/spec/models/book/enhancer_spec.rb
index e8d5006..884d8df 100644
--- a/spec/models/book/enhancer_spec.rb
+++ b/spec/models/book/enhancer_spec.rb
@@ -25,6 +25,20 @@
       end
     end
 
+    context "with empty api data" do
+      let(:api_data) { {} }
+      let(:isbn) { "123456789" }
+
+      it "does nothing" do
+        expect(OpenLibraryApi).to receive(:get_book).and_return(api_data)
+        book.enhancer.update_from_api
+
+        expect(book.isbn).to eq "123456789"
+        expect(book.pages).to eq nil
+        expect(book.title).to eq nil
+      end
+    end
+
     context "with a book that has none for isbn" do
       let(:isbn) { "none" }