add method to merge unique values of JSON results

app/services/ams/missing_instantiations_locator.rb

@@ -92,5 +92,23 @@ def write_results
         f.puts results.to_json
       end
     end
+
+    def merge_all_results
+      results_files = Dir.glob(WORKING_DIR.join('i16-AMS1Importer*.json'))
+      base_hash = JSON.parse(File.read(results_files.shift))
+      progressbar = ProgressBar.create(total: results_files.size, format: '%a %e %P% Processed: %c from %C')
+
+      results_files.each do |file|
+        merging_hash = JSON.parse(File.read(file))
+        base_hash.merge!(merging_hash) do |_inst_id, base_asset_id, merging_asset_id|
+          base_asset_id | merging_asset_id
+        end
+        progressbar.increment
+      end
+
+      File.open(WORKING_DIR.join('i16-combined-results.json', 'w')) do |file|
+        file.puts base_hash.to_json
+      end
+    end
   end
 end