Raise if unknown mimetype

As part of this I've registered the 'wav' mimetype as some scratch assets are wav files.

Author: zetter-rpf

config/initializers/mime_types.rb

@@ -0,0 +1,3 @@
+# frozen_string_literal: true
+
+Mime::Type.register 'audio/vnd.wav', :wav

lib/scratch_asset_importer.rb

@@ -34,7 +34,7 @@ def initialize(asset_name, asset_base_url)
   def import
     create_scratch_asset
     save_to_editor_asset_bucket
-  rescue StandardError => e
+  rescue Faraday::Error => e
     Rails.logger.error("Failed to import asset #{asset_name}: #{e.message}")
   end
 
@@ -84,7 +84,10 @@ def asset_key
 
   def asset_content_type
     extension = File.extname(asset_name).delete('.')
-    Mime::Type.lookup_by_extension(extension).to_s
+    mime_type = Mime::Type.lookup_by_extension(extension)
+    raise "Unknown content type for extension: #{extension}" unless mime_type
+
+    mime_type.to_s
   end
 
   def s3_client

spec/fixtures/files/unknown_mime_type.xyz

@@ -105,6 +105,17 @@
         described_class.import_all(['123abc.png'], 'https://example.net/internalapi/asset/')
         expect(s3_client).not_to have_received(:put_object)
       end
+
+      it 'raises if asset is an unknown mimetype' do
+        image = Rails.root.join('spec/fixtures/files/unknown_mime_type.xyz').read
+        stub_request(:get, 'https://example.net/internalapi/asset/unknown_mime_type.xyz/get/').to_return(status: 200, body: image)
+
+        expect do
+          described_class.import_all(['unknown_mime_type.xyz'], 'https://example.net/internalapi/asset/')
+        end.to raise_error('Unknown content type for extension: xyz')
+
+        expect(s3_client).not_to have_received(:put_object)
+      end
     end
   end
 end