Thanks, I was thinking of saving the attachment ids with a scheme such as:
Code:
mr:epub_12345&mobi_23456&pdf_34567
I've written a metadata source plugin that picks up one of the formats (configurable) in the identifier and generates an url, with the get_book_url() method. Would it be possible to extend the feature such that it can return a list of 3-tuples instead of a single one (and use all the returned urls)?