The operation attribute gives the status of the new file (where applicable) in relation to what has been submitted previously, and it has the following possible values:
- “new” – the file in question is a new file unrelated to anything submitted previously
- “append” – the file in question is being appended to a file submitted previously, at the location specified in the “modified-file” attribute
- “replace” – a file that replaces a file submitted previously, at the location specified in the “modified-file” attribute
- “delete” – a file submitted previously, at the location specified in the “modified-file” attribute, is being deleted without being replaced.