BookSync-a web page to access Calibre Libraries on Dropbox

[slm]

BookSync is a rough-and-ready solution for accessing your Calibre Libraries stored on Dropbox from the internet. It is a simple web page, accessible from any device with an internet connection and a browser. It was prompted by the various Android and iOS apps that access Calibre’s books through Dropbox, collect a nice following and then don’t keep up with changes to Androi, iOS or Calibre.

Basically, BookSync shows you of list of your books by title and author and lets you do simple searches. Tapping a book title will bring up a standard “details” page—author, title, book cover and blurb. It will also provide a download button for downloading the book to the device your browser is running on.

BookSync is a simple web page: it doesn’t collect any information, and it doesn’t need to be “installed” into iOS or Android to run. Although it reads files and folders in your DropBox account, it does not write to them. BookSync is a “PWA” , which means that if you use the right Browser, it can be “installed” on you device and pretend to be an app.

Book Sync is fairly robust because, although it uses the Calibre library database, it does so on minimal assumptions. Basically, so long as the database continues to have a table called “books” that continues to have columns called “title”, “author_sort” and “path” that contain what the title says, the program should be indifferent to changes in the structure of the Calibre database.

BookSync should not require any author intervention in the future: it doesn’t relay on anything in Android or iOS code other than basic Browser functionality. (The source code is available to anyone who wants to run it (with necessary changes) from their own server.)
The decision to make limited assumptions about the Calibre database does slow things down. It takes about 5 seconds to build the list of my 3500 books. Larger libraries make take longer to load, but probably not an immense amount of time

[slm]

Fixed a stupid choice, now scans all 3500 books in 2 seconds!
(I've changed some of the text in the first post)

[Sirtel]

Hmm. For some reason it only shows books from one of my libraries (the largest), but not from others. And filtering seems to be very buggy - when I try to filter by the name of the author, several duplicate entries are displayed and many entries aren't displayed.

[slm]

Thanks for trying this out.


I can replicate the filtering problem, but it isn't actually the filtering but the file list--for some reason, some books are "found" more than once in the search. This is "supposed" to happen, according to my very limited understanding.
I'm trying to figure out why is does.

As to missing your other library, a couple of questions may help:
1. how may books are in each library?
2. Can you open the folder for one of the books in the library that was missed and check that that folder does in fact contain a file whose name is "metadata.opf" (I can't imaging why it wouldn't but that is what the program searches for).
3. Finally, what OS are you on and what Browser? (Neither of these should matter, but it might be a place to start)

[Sirtel]

You mean metadata.db, I think? Yes, they all have it. And all the books have metadata.opf files as well.

The largest is over 35 000 books and alphabetically the first one. The other two (that the app couldn't find) are about 5000 and 3000.

And the issue with filtering is not only duplicates, it's also that many books for the filtered author(s) aren't shown at all. I think the app may have problems with huge libraries - maybe it's unable to process such a number of books and that's the reason for both missing libraries and missing books.

I'm on Windows 11, the browser is Thorium (a Chromium fork. It's the only one where I'm logged in to Dropbox).

[slm]

Originally Posted by Sirtel

You mean metadata.db, I think? Yes, they all have it. And all the books have metadata.opf files as well.

Actually, I really did mean "metadata.opf". Each library has a metadata.db file but each book has a metadata.opf file. (the "opf" file contains information, or references to the information that Calibre uses for the book. Calibre uses this to rebuild the database if it gets corrupted.)

[slm]

By the way, how long does it take to search 35,000 books?

[Sirtel]

Originally Posted by slm

By the way, how long does it take to search 35,000 books?

Less than a minute, but I suspect it's stopping long before it has scanned all of them. The list is displayed after it found 9000. So maybe that's the limit.

[slm]

Your guess turns out to be correct: I verified it empircally and then did a search of the documentation, which does state this limit.

I've modified the initial post to warn that the program does not work correctly with large libraries.

I've actually found the recommended approach for larger searches but (because I tried using this technique at one point), I think it will be too slow to be reasonable for large libraries. I'm going to play with it a bit more to be sure.

Thank you very much for your help.

[slm]

@sirtel: The duplicated files issue has been solved. Not that it will do you can good, of course, since the 10,000 books limit is still present.

[Sirtel]

Thanks.

It's a pity there's no option to select a library. I'd give it a go at one of my smaller ones.

[slm]

Current version now checks for multiple libraries and offers a choice of them if more than one is found. (Some of the offered libraries may be spurious.)

First Post will be updated to reflect this

[Sirtel]

Originally Posted by slm

Current version now checks for multiple libraries and offers a choice of them if more than one is found. (Some of the offered libraries may be spurious.)

First Post will be updated to reflect this

Doesn't work. Yes, it offers a choice, but it still only scans the books from the alphabetically first library, not the one selected.

[slm]

@sirtel: stupid typing error. Fixed (I hope). Should work now--seems to work on mine.

[Sirtel]

Originally Posted by slm

@sirtel: stupid typing error. Fixed (I hope). Should work now--seems to work on mine.

Nope, no change. Still scanning the wrong library.