Feature request: Preferred download format

[Kakunas]

If a book have multiple formats like pdf, epub, azw3 you must chosse the right format in the download dropdown menue. Maybe it is possible to define a preferred format which one i mostly want to download. Like the look if only one format is available, but with the option to dropdown the download menue.

[pollitor]

Better than that, it would be great to allow the user to choose a preferred format and perform an automatic conversion on the fly on download if the book is not available in the calibre library in the chosen format.

• The preferred format would be configurable for each user of calibre-web.
• In the current web interface, conversion is only possible with the permission to edit the book's metadata in the library, which makes it cumbersome to download a book in another format than the one available in the library, and impossible if the user does not has permissions to change the book's metadata. This feature would not require permission to edit the metadata, unless you want to save the new format to the library.
• This feature would also be applicable to the OPDS catalog and would greatly facilitate the simple download of books in a suitable format for each user.
• It does not need to replace the existing download list of formats available in the caliber library in the web interface, it can be added if the library does not have the book in that format.
• The behavior could also be configured to do a conversion that would save the new format to the library or do the conversion on the fly without saving it to the library.
• As in the case of the format conversion that is already available, access to calibre software's ebook-convert tool needs to be configured correctly.