[It broke]: Downloaded issues from Tranga show a "can not read" error in kavita

[Paraxes]

What is broken?

Hello, I have a bizarre issue. I am using "Tranga" as software to download chapters and then trigger a manual scan of the library in Kavita.

However, every time Kavita shows me the "cannot read" error and tells me "There are no pages". However, if I simply copy and paste the same folder with the chapters in them on my NAS and overwrite the original files with the same files (and change nothing else, same folder and everything) and rescan via Kavita again it doesn't display any errors.

I originally thought that Kavita was maybe picking up chapters while they are downloading, hence the error, but since I have not enabled an automatic library scan, this isn't the issue.

I also tried it with Tranga being connected to Kavita and without being connected - same error.

The chapters are acutally working if I manually open them with something like CDisplayEX for example. It almost feels like there's some kind of "flag/hidden file" (for a lack of a better term) that makes Kavita not being able to read the chapters/files initially until they are overwritten once.

Other useres in the Kavita discord have the same issues and the Kavita developer doesn't really know what the issue is, so I thought I'd ask here.

Thank you!

[C9Glax]

I originally thought that Kavita was maybe picking up chapters while they are downloading, hence the error, but since I have not enabled an automatic library scan, this isn't the issue.

Correct, Tranga copies the completed archive.

From your description it sounds like a permission thing. Can you check after change the owner/group of the files, if it works then?

[Paraxes]

First of all, thank you for the quick answer.

I freely admit that I am a bit of a newbie when it comes to docker. The permission issue would make sense, though since Kavita is actually assigned to the PUID/PGID "1024:100" and tranga previously was not.

I deploy tranga via docker compose in portainer and just tried to add my PGID/PUID since you mentioned the permissions via the "USER_ID" and "GROUP_ID" environmental variable (which is hopefully the correct way to do it, otherwise I will gladly listen to you on how to do it otherwise) and tried it again but sadly the issue persists.

Other than via the "USER_ID/GROUP_ID" variable I am not sure how I'd go about changing the owner/group of the files to be honest.

version: '3'
services:
  tranga-api:
    image: glax/tranga-api:cuttingedge
    container_name: tranga-api
    volumes:
      - /volume1/Multimedia/zzzKavitaBib/Manga/Englisch:/Manga
      - /volume1/docker/tranga:/usr/share/tranga-api
    environment:
      - USER_ID=1024
      - GROUP_ID=100
    ports:
      - "6531:6531"
    restart: unless-stopped
  tranga-website:
    image: glax/tranga-website:cuttingedge
    container_name: tranga-website
    environment:
      - USER_ID=1024
      - GROUP_ID=100
    ports:
      - "9555:80"
    depends_on: 
      - tranga-api
    restart: unless-stopped

[C9Glax]

It's been a while since I wrote the file-code, can you just confirm that the files are actually user:group 1024:100? ls -la As far as I can remember, I don't actually use the user and group to assign perms...

[Paraxes]

You seem to be correct. I used the console in portainer on the tranga-api container and can't see the assigned user permissions

Your hunch about permissions seems to be right, though. I guess Kavita doesn't have permission to actually view the files inside the downloaded chapters by Tranga. It sees the folder and the .cbz files but as soon as it starts to scan it can't access them and thus reports that there are no pages in them. This also explains why in a new folder created by me through the normal windows explorer everything works just fine even though the files are the same.

This is the Kavita log btw.

I don't know how to sort that permission issue out, though (except for assigning the groups in the compose which didn't work since, like you said, you don't assign permissions that way).

Like I said in my original comment, another user on the Kavita discord has the exact same issue, so it isn't an exclusive issue on my end.

[C9Glax]

I think you created the docker container with the root user, so files will all be owned by root. Try giving your standard user docker perms (groupadd docker or something like that, don't know off the top of my head) and recreate the container.

Edit: Or even better have a docker-user

[Paraxes]

Thank you. Since it seems to be an error on my part in terms of permissions then and is not directly related to a fault with tranga I'll try to sort it out and will mark this closed then.

[C9Glax]

If it isn't resolved feel free to reopen ofc :)