While trying to download a youtube video: No such file or directory: 'lb-wrapper'

[Akatama]

Describe the bug/problem

While writing some integration tests for Calibre-Web, I have decided to test downloading videos from Youtube. I submitted 3 such videos, and after waiting for 10 minutes, I saw no change in behavior. I clicked the Tasks button and saw this error for my video:

Admin Metadata Fetch: https://www.youtube.com/watch?v=mUxzKVrSAjs failed: [Errno 2] No such file or directory: 'lb-wrapper'

To Reproduce

Steps to reproduce the behavior:

1. Create a Python virtual environment
2. pip install -r requirements.txt
3. Run nohup python3 cps.py & to enable the application
4. Open the browser to http://localhost:8083
5. Click on 'Download to IIAB'
6. Enter in the Youtube video URL
7. Click Submit
8. Wait a few minutes, then click on the Tasks button

Logfile

 688   │ [2025-09-07 20:40:32,939] DEBUG {uploader.py:392} Temporary file: /tmp/calibre_web/afccbdf30b8a56883b178f783e39cd9f
 689   │ [2025-09-07 20:40:33,135] DEBUG {helper.py:536} Moving title: /tmp/calibre_web/afccbdf30b8a56883b178f783e39cd9f to /library/calibre-web/Robert W. Chambers/The King in Yellow (5)
 690   │ [2025-09-07 20:40:33,148] DEBUG {worker.py:91} Add Task for user: Admin - Upload The King in Yellow
 691   │ [2025-09-07 20:40:33,719] DEBUG {uploader.py:392} Temporary file: /tmp/calibre_web/898973dc73bd98269d5747aeaafffbc6
 692   │ [2025-09-07 20:40:33,883] DEBUG {helper.py:536} Moving title: /tmp/calibre_web/898973dc73bd98269d5747aeaafffbc6 to /library/calibre-web/Alexandre Dumas/The Count of Monte Cristo (6)
 693   │ [2025-09-07 20:40:33,898] DEBUG {worker.py:91} Add Task for user: Admin - Upload The Count of Monte Cristo
 694   │ [2025-09-07 21:06:48,309] DEBUG {worker.py:91} Add Task for user: Admin - Metadata fetch task for https://www.youtube.com/watch?v=mUxzKVrSAjs
 695   │ [2025-09-07 21:06:48,309]  INFO {metadata_extract.py:155} Starting to fetch metadata for URL: https://www.youtube.com/watch?v=mUxzKVrSAjs
 696   │ [2025-09-07 21:06:48,310] ERROR {metadata_extract.py:54} An error occurred during subprocess execution: [Errno 2] No such file or directory: 'lb-wrapper'
 697   │ [2025-09-07 21:08:56,110] DEBUG {worker.py:91} Add Task for user: Admin - Metadata fetch task for https://www.youtube.com/watch?v=mUxzKVrSAjs
 698   │ [2025-09-07 21:08:56,326]  INFO {metadata_extract.py:155} Starting to fetch metadata for URL: https://www.youtube.com/watch?v=mUxzKVrSAjs
 699   │ [2025-09-07 21:08:56,326] ERROR {metadata_extract.py:54} An error occurred during subprocess execution: [Errno 2] No such file or directory: 'lb-wrapper'
 700   │ [2025-09-07 21:17:00,961] DEBUG {worker.py:91} Add Task for user: Admin - Metadata fetch task for https://www.youtube.com/watch?v=mUxzKVrSAjs
 701   │ [2025-09-07 21:17:00,961]  INFO {metadata_extract.py:155} Starting to fetch metadata for URL: https://www.youtube.com/watch?v=mUxzKVrSAjs
 702   │ [2025-09-07 21:17:00,962] ERROR {metadata_extract.py:54} An error occurred during subprocess execution: [Errno 2] No such file or directory: 'lb-wrapper'

Expected behavior

I expect the video to be downloaded and available in Calibre-Web with as little delay as possible,

Environment (please complete the following information):

• OS: OpenSUSE Tumbleweed 20250829
• Python version: 3.13.7
• Calibre-Web version: 0.6.26 Beta
• Docker container: [None/LinuxServer]: None
• Special Hardware: This is just my computer
• Browser: Firefox 141.0.2

[holta]

@chapmanjacobd any idea what's happening here?

Even if (FWIW!) OpenSUSE is not one of IIAB's ~5 mainline OS's:

https://wiki.iiab.io/go/FAQ#What_OS_should_I_use%3F

[holta]

failed: [Errno 2] No such file or directory: 'lb-wrapper'

@Akatama for CI testing things might be different (?) — but does the standard installation path (https://github.com/iiab/calibre-web/wiki#wrench-installation) onto an Ubuntu VM at least work?

[Akatama]

@holta I'll test with a mutlipass vm on my laptop when I get a chance. My suspicion, however, is that there is a dependency missing from requirements.txt.

[chapmanjacobd]

I'm familiar with OpenSUSE and Fedora. But I'm having trouble installing IIAB on OpenSUSE

@Akatama How did you install IIAB? Or did you only install iiab/calibre-web?

[Akatama]

I only ran iiab/calibre-web, as I explained in the report with nohup python3 cps.py &.

I have not installed IIAB on openSUSE Tumbleweed and do not intend to do so.

[chapmanjacobd]

I think I understand what's going on a bit more now. I think you'll need to add the calibre-web/scripts folder to the PATH of the environment that is running calibre-web.

$ rg -i --no-heading --no-line-number -j1 lb_executable
cps/tasks/download.py:        lb_executable = os.getenv("LB_WRAPPER", "lb-wrapper")
cps/tasks/download.py:            subprocess_args = [lb_executable, "dl", self.media_url]

or set LB_WRAPPER to the absolute path of the file calibre-web/scripts/lb-wrapper as an environment variable in the environment that is running calibre-web

[Akatama]

@chapmanjacobd Thanks! I will try this out after I put my daughter to bed.

If we haven't already, can we please put these instructions in the README once I confirm it works? I see you have a README related PR today so you may have already done it.

We have two workflows that run tests, and one of them only runs Calibre-Web without installing IIAB, so we need to know how to set up stuff like this for that workflow.

[Akatama]

@chapmanjacobd This didn't fully work, but it seems to be on the right path.

I now have this error: no such table: media

Looking at the task itself, it looks like the video completed downloading but we couldn't store it in the database.

The database file is app.db from IIAB's master branch. It's located in the Calibre-Web role, so presumably it is the same database file that ends up being used in IIAB itself:
wget -O app.db https://github.com/iiab/iiab/raw/refs/heads/master/roles/calibre-web/files/app.db

Although I did get this particular one last week. I may try a fresh download of that file and see if it helps.

[chapmanjacobd]

can you run $ library sdb /library/calibre-web/xklb-metadata.db media mUxzKVrSAjs

?

You may need to run pip install library first (or pipx)

[Akatama]

@chapmanjacobd I did have to install library.

The output of that command was this:

ValueError: Table media does not exist in /library/calibre-web/xklb-metadata.db

Then I wiped out app.db and xklb-metadata.db, redownloaded app.db and started over. This time I got a bit farther.

Output of the command now:
{"id": 1, "playlists_id": null, "time_created": 1757393196, "time_modified": 0, "time_deleted": 0, "time_uploaded": 1684759504, "time_downloaded": 0, "size": 0, "duration": 574, "view_count": 101776, "path": "https://www.youtube.com/watch?v=mUxzKVrSAjs", "webpath": "https://www.youtube.com/watch?v=mUxzKVrSAjs", "extractor_id": "mUxzKVrSAjs", "float": null, "title": "Nature | Waterfalls | Drone | Free HD Videos - No Copyright footage", "fps": 0.0, "live_status": "not_live", "uploader": "UCJ0BmJOn_bRKiApjc45QZ1w", "error": null}

It finished the metadata fetch, but failed to download still:

Output of echo $LB_WRAPPER is:
/home/jimmy/Documents/repos/calibre-web/scripts/lb-wrapper

That's the correct full path for $LB_WRAPER for my computer.

[chapmanjacobd]

That's weird that it just has one row? I'm not too familiar with the lb-wrapper.

@deldesir Is the output of the Tasks table from app.db? Or where?

Also, what does failed to download: None mean? is it just that the output_path doesn't exist but no error message?

I'll try to download some things tomorrow and see if I can get the same behavior. It would be good if we could bubble up the original error match

Without the logs I don't have a hunch for what is going on. It could be any number of things

[Akatama]

@chapmanjacobd I will try to look into this further tomorrow too. It's almost time for me to head to bed. I appreciate your help, Jacob, all of this will be good to add to both the README and the Integration test workflow.

I re-ran library sdb /library/calibre-web/xklb-metadata.db media mUxzKVrSAjs. It is the same output, but just for completeness sake:

{"id": 1, "playlists_id": null, "time_created": 1757393196, "time_modified": 0, "time_deleted": 0, "time_uploaded": 1684759504, "time_downloaded": 0, "size": 0, "duration": 574, "view_count": 101776, "path": "https://www.youtube.com/watch?v=mUxzKVrSAjs", "webpath": "https://www.youtube.com/watch?v=mUxzKVrSAjs", "extractor_id": "mUxzKVrSAjs", "float": null, "title": "Nature | Waterfalls | Drone | Free HD Videos - No Copyright footage", "fps": 0.0, "live_status": "not_live", "uploader": "UCJ0BmJOn_bRKiApjc45QZ1w", "error": null}

I did not see a Tasks table in app.db. I did poke around there a little bit to see if I could find where the Tasks are stored.

Here are the relevant log entries for the metadata fetch and failed download:

  44   │ [2025-09-08 21:46:30,425] DEBUG {worker.py:91} Add Task for user: Admin - Metadata fetch task for https://www.youtube.com/watch?v=mUxzKVrSAjs
  45   │ [2025-09-08 21:46:30,426]  INFO {metadata_extract.py:155} Starting to fetch metadata for URL: https://www.youtube.com/watch?v=mUxzKVrSAjs
  46   │ [2025-09-08 21:46:37,079] DEBUG {worker.py:91} Add Task for user: Admin - Download task for https://www.youtube.com/watch?v=mUxzKVrSAjs
  47   │ [2025-09-08 21:46:37,086]  INFO {download.py:43} Subprocess args: ['/home/jimmy/Documents/repos/calibre-web/scripts/lb-wrapper', 'dl', 'https://www.youtube.com/watch?v=mUxzKVrSAjs']
  48   │ [2025-09-08 21:46:47,259] ERROR {download.py:131} An error occurred during the subprocess execution: 'NoneType' object is not subscriptable

[chapmanjacobd]

hmm yeah it looks like the lb-wrapper has quite a few reasonable assumptions about the IIAB environment that it was built to run inside of. I think a few edits might need to be made before it will be portable

scripts/lb-wrapper dl https://www.youtube.com/watch?v=mUxzKVrSAjs
mkdir: cannot create directory ‘/library’: Permission denied
/home/xk/.local/bin/lb
/home/xk/.local/bin/yt-dlp
tee: /var/log/xklb.log: Permission denied
2025-09-09 00:48:02 - [Info] Using yt-dlp 2025.09.08.232917
tee: /var/log/xklb.log: Permission denied
2025-09-09 00:48:02 - [Info] Running xklb command: lb dl '/library/calibre-web/xklb-metadata.db' --video --search 'https://www.youtube.com/watch?v=mUxzKVrSAjs' --subs --write-thumbnail --live --live-from-start -o'/library/downloads/calibre-web/%(extractor_key,extractor)s/%(uploader,uploader_id)s/%(title).170B_%(view_count)3.2D_[%(id).64B].%(ext)s' --format=best --format-sort='tbr~1000' -vv
tee: /var/log/xklb.log: Permission denied
2025-09-09 00:48:02 - [Debug] library v3.0.120 :: /home/xk/.local/bin
tee: /var/log/xklb.log: Permission denied
2025-09-09 00:48:02 - [Debug] ['/home/xk/.local/bin/lb', 'dl', '/library/calibre-web/xklb-metadata.db', '--video', '--search', 'https://www.youtube.com/watch?v=mUxzKVrSAjs', '--subs', '--write-thumbnail', '--live', '--live-from-start', '-o/library/downloads/calibre-web/%(extractor_key,extractor)s/%(uploader,uploader_id)s/%(title).170B_%(view_count)3.2D_[%(id).64B].%(ext)s', '--format=best', '--format-sort=tbr~1000', '-vv']
tee: /var/log/xklb.log: Permission denied
2025-09-09 00:48:02 - [Debug] {'include': ['https://www.youtube.com/watch?v=mUxzKVrSAjs'], 'subs': True, 'live': True, 'ext': (), 'paths': []}
tee: /var/log/xklb.log: Permission denied

...

[holta]

Incredible progress! Great news @Akatama & @chapmanjacobd that you were able to push this far. 🎯

Hopefully @deldesir too, might have recommendations in coming days. 😀