Custom external commands in the GUI
I have several custom scripts that perform some (ebook/ereader related) actions that Calibre does not implement on its own. I was wondering whether there exists a mechanism to integrate them in the Calibre GUI. It could simply mean adding a button with user specified name to user specified group which would simply run a user specified command and return information about success/failure (through or besides the Calibre job management).
In case there is no mechanism for custom commands from GUI: it should not be difficult for me to write Calibre GUI plugins that would do what I describe above. But is there a way to set things up so that the custom plugins survive a binary Calibre update while all the remaining 'stock' Calibre functionality comes in binary form? I have read about the development environment but I am not sure it would enable this?