Cancel book import from inside a FileTypePlugin

Leseratte_10 · 09-04-2021, 03:00 PM

Hello,

is there a way for a Calibre FileTypePlugin to completely abort importing the current book (and ideally return an error message to the user)?

If I have a FileTypePlugin that's supposed to parse a custom file type and convert that into a format that Calibre understands, I'd like to be able to be like "Okay, this file the user is trying to import *is* in my custom file format (so don't try other file import plugins), but it's damaged / corrupted or otherwise unsuitable to use (so also don't import it into the database).

When I just return the original unmodified file path, or when I throw an Exception in the "run" function of my plugin class, Calibre just hands that book down to the next FileTypePlugin in line, or if there is none, imports it as-is. That results in an unusable book entry in Calibre that the user has to manually delete again.

Is there a way I can convey to calibre that the file is broken and to stop importing it and instead display a custom error message to the user?

I have read the plugin documentation and the plugin creation guide but I was unable to find that functionality in there.

Is that hidden somewhere, or is that something that Calibre doesn't support?

BetterRed · 09-04-2021, 06:42 PM

Moderator Notice
Moved from Plugins forum to Development forum

BR

kovidgoyal · 09-04-2021, 10:10 PM

There isn't, filetype plugins cannot abort the input process and they definitely cannot interact witht he user, since they can be run in worker processes, in parallel, from the CLI, from the content server, etc.

I am assuming that your plugin is converting some custom format to a format calibre understands, so just have it return the original and that should be a good enough indication that your plugin failed.

09-04-2021, 03:00 PM	#1
Leseratte_10 Groupie Posts: 183 Karma: 3587000 Join Date: Sep 2021 Device: PB Era, PB InkPad 3 Pro	Cancel book import from inside a FileTypePlugin Hello, is there a way for a Calibre FileTypePlugin to completely abort importing the current book (and ideally return an error message to the user)? If I have a FileTypePlugin that's supposed to parse a custom file type and convert that into a format that Calibre understands, I'd like to be able to be like "Okay, this file the user is trying to import is in my custom file format (so don't try other file import plugins), but it's damaged / corrupted or otherwise unsuitable to use (so also don't import it into the database). When I just return the original unmodified file path, or when I throw an Exception in the "run" function of my plugin class, Calibre just hands that book down to the next FileTypePlugin in line, or if there is none, imports it as-is. That results in an unusable book entry in Calibre that the user has to manually delete again. Is there a way I can convey to calibre that the file is broken and to stop importing it and instead display a custom error message to the user? I have read the plugin documentation and the plugin creation guide but I was unable to find that functionality in there. Is that hidden somewhere, or is that something that Calibre doesn't support?

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Searching inside the book	Sirtel	Barnes & Noble NOOK	5	07-23-2019 07:24 PM
Import on Filename changes mid import due to book error	Vortex	Calibre	3	12-05-2014 11:49 AM
FileTypePlugin, config_widget, JSONConfig and Cancel	Apprentice Alf	Development	3	02-28-2013 12:41 PM
How to cancel 'book' generation if no articles found	Big Al	Recipes	3	01-31-2011 07:13 PM
Cover inside book	luthar28	ePub	3	08-04-2010 05:32 PM

09-04-2021, 06:42 PM	#2
BetterRed null operator (he/him) Posts: 21,717 Karma: 29711016 Join Date: Mar 2012 Location: Sydney Australia Device: none	Moderator Notice Moved from Plugins forum to Development forum BR

09-04-2021, 10:10 PM	#3
kovidgoyal creator of calibre Posts: 45,342 Karma: 27182818 Join Date: Oct 2006 Location: Mumbai, India Device: Various	There isn't, filetype plugins cannot abort the input process and they definitely cannot interact witht he user, since they can be run in worker processes, in parallel, from the CLI, from the content server, etc. I am assuming that your plugin is converting some custom format to a format calibre understands, so just have it return the original and that should be a good enough indication that your plugin failed.

Advert