Better error handling

Author: whomingbird

lib/seek/doi/parser.rb

@@ -7,6 +7,7 @@ class Parser
       DOI_ENDPOINT = 'https://doi.org'.freeze
 
       def self.parse(doi)
+
         agency = get_doi_ra(doi)
 
         case agency

lib/seek/doi/parsers/base_parser.rb

@@ -12,26 +12,24 @@ def parse(doi)
           Rails.logger.info("Fetching metadata for DOI #{doi} from #{url}")
 
           response = perform_request(url)
-          return nil unless response.is_a?(Net::HTTPSuccess)
-
-          begin
-            data = parse_response_body(response)
-            raise "Missing metadata in response" unless data
-
-            data = decode_html_entities_in_hash(data)
-            metadata = extract_metadata(data)
-            metadata[:citation] ||= build_citation(metadata)
-
-            build_struct(metadata)
-          rescue JSON::ParserError => e
-            Rails.logger.error("JSON parse error for DOI #{doi}: #{e.message}")
-            nil
-          rescue StandardError => e
-            Rails.logger.error("Unexpected error parsing DOI #{doi}: #{e.message}")
-            nil
-          end
+          data = parse_response_body(response)
+
+          raise Seek::Doi::ParseException, "Empty metadata response for DOI #{doi}" if data.blank?
+
+          metadata = decode_html_entities_in_hash(extract_metadata(data))
+          metadata[:citation] ||= build_citation(metadata)
+
+          build_struct(metadata)
+
+        rescue JSON::ParserError => e
+          raise Seek::Doi::ParseException, "Error parsing JSON for DOI #{doi}: #{e.message}"
+        rescue Seek::Doi::BaseException
+          raise
+        rescue StandardError => e
+          raise Seek::Doi::ParseException, "Unexpected error while parsing DOI #{doi}: #{e.message}"
         end
 
+
         protected
 
         def normalize_metadata(raw)
@@ -79,12 +77,22 @@ def perform_request(uri, accept_header: 'application/json')
             request = Net::HTTP::Get.new(uri)
             request['Accept'] = accept_header
             response = http.request(request)
-            Rails.logger.debug("HTTP #{response.code} #{response.message} for #{uri}")
-            response
+
+            case response.code.to_i
+            when 200
+              response
+            when 204
+              raise Seek::Doi::FetchException, "No metadata available for DOI #{uri}"
+            when 404
+              raise Seek::Doi::NotFoundException, "DOI not found: #{uri}"
+            else
+              raise Seek::Doi::FetchException, "Unexpected HTTP #{response.code} #{response.message} for #{uri}"
+            end
           end
-        rescue SocketError, Timeout::Error, StandardError => e
-          Rails.logger.error("Network error fetching #{uri}: #{e.message}")
-          nil
+        rescue SocketError, Timeout::Error => e
+          raise Seek::Doi::FetchException, "Network error fetching DOI metadata: #{e.message}"
+        rescue URI::InvalidURIError => e
+          raise Seek::Doi::MalformedDOIException, "Invalid DOI or malformed URI: #{e.message}"
         end
 
 

lib/seek/doi/parsers/crossref_parser.rb

@@ -50,8 +50,8 @@ def extract_date(data)
           end
 
           date_parts = get_date_parts.call('issued') ||
-            get_date_parts.call('published') ||
-            get_date_parts.call('published-print')
+                       get_date_parts.call('published') ||
+                       get_date_parts.call('published-print')
           date_parts ? (Date.new(*date_parts) rescue nil) : nil
         end
 

lib/seek/doi/parsers/datacite_parser.rb

@@ -43,7 +43,11 @@ def extract_date(data)
           if data['publicationYear']
             Date.new(data['publicationYear'].to_i)
           elsif (issued = Array(data['dates']).find { |d| d['dateType'] == 'Issued' })
-            Date.parse(issued['date']) rescue nil
+            begin
+              Date.parse(issued['date'])
+            rescue
+              nil
+            end
           end
         end
 

test/unit/doi/crossref_parser_test.rb

@@ -41,6 +41,18 @@ class DoiParserExceptionTest < ActiveSupport::TestCase
     end
   end
 
+
+  test 'raises ParseException when Crossref returns invalid JSON' do
+    doi = '10.1016/j.patter.2025.101345'
+
+    VCR.use_cassette('doi/invalid_json_response') do
+      error = assert_raises(Seek::Doi::ParseException) do
+        Seek::Doi::Parser.parse(doi)
+      end
+      assert_match /Error parsing JSON for DOI/, error.message
+    end
+  end
+
 end