fix: returning attachment preview when not annotated (#2192)

when the attachment does not have annotation derivative
calling /api/v1/attachments/{attachment id}/annotated_image raises


TODO: check why the calls are made for non annotated attachment

app/api/chemotion/attachment_api.rb

@@ -219,31 +219,19 @@ def remove_duplicated(att)
       desc 'get_annotated_image_of_attachment'
       get ':attachment_id/annotated_image' do
         content_type 'application/octet-stream'
-
         env['api.format'] = :binary
 
-        store = @attachment.attachment.storage.directory
-        file_location = store.join(
-          @attachment.attachment_data['derivatives']['annotation']['annotated_file_location'] || 'not available',
-        )
-
-        uploaded_file = if file_location.present? && File.file?(file_location)
-                          extension_of_annotation = File.extname(@attachment.filename)
-                          extension_of_annotation = '.png' if @attachment.attachment.mime_type == 'image/tiff'
-                          filename_of_annotated_image = @attachment.filename.gsub(
-                            File.extname(@attachment.filename),
-                            "_annotated#{extension_of_annotation}",
-                          )
-                          header['Content-Disposition'] = "attachment; filename=\"#{filename_of_annotated_image}\""
-                          File.open(file_location)
-                        else
-                          header['Content-Disposition'] = "attachment; filename=\"#{@attachment.filename}\""
-                          @attachment.attachment_attacher.file
-                        end
-        data = uploaded_file.read
-        uploaded_file.close
-
-        data
+        annotation = @attachment.annotated_file_location.presence
+        if annotation.present? && File.file?(annotation)
+          header['Content-Disposition'] = "attachment; filename=\"#{@attachment.annotated_filename}\""
+          file = File.open(annotation)
+        else
+          header['Content-Disposition'] = "attachment; filename=\"#{@attachment.filename}\""
+          file = @attachment.attachment_attacher.file
+        end
+        file.read
+      ensure
+        file&.close
       end
 
       desc 'update_annotation_of_attachment'
@@ -314,13 +302,12 @@ def remove_duplicated(att)
             next unless att.annotated?
 
             begin
-              annotated_file_name = "#{File.basename(att.filename, '.*')}_annotated#{File.extname(att.filename)}"
-              zip.put_next_entry annotated_file_name
+              zip.put_next_entry att.annotated_filename
               file = File.open(att.annotated_file_location)
               zip.write file.read
-              file_text += "#{annotated_file_name} #{file.size}\n"
+              file_text += "#{att.annotated_filename} #{file.size}\n"
             ensure
-              file.close
+              file&.close
             end
           end
 

app/models/attachment.rb

@@ -237,7 +237,7 @@ def type_image_tiff?
 
   def annotated?
     # attachment['derivatives'].present? && attachment['derivatives']['annotation'].present?
-    attachment_data&.dig('derivatives', 'annotation', 'annotated_file_location')&.present? || false
+    attachment_data&.dig('derivatives', 'annotation', 'annotated_file_location').present? || false
   end
 
   def annotated_image?
@@ -249,6 +249,7 @@ def type_pdf?
     attachment['mime_type'].to_s == 'application/pdf'
   end
 
+  # @return [String] the path to the combined image file on disk
   def annotated_file_location
     return '' unless annotated?
 
@@ -258,6 +259,15 @@ def annotated_file_location
     )
   end
 
+  # @return [String] build annotation file name based on the original file name
+  def annotated_filename
+    return '' unless annotated?
+
+    # NB: original tiff file are converted to png for the annotation background layer
+    extension_of_annotation = content_type == 'image/tiff' ? '.png' : File.extname(filename)
+    "#{File.basename(filename, '.*')}_annotated#{extension_of_annotation}"
+  end
+
   def preview
     "data:image/png;base64,#{Base64.encode64(read_thumbnail)}" if thumb
   end