docker-compose creates directory instead of file

Question

I'm trying to setup my home server (Ubuntu 18.04 LTS) using some docker containers and docker-compose. While trying to setup the "transmission-rss" I get the following error:

/usr/local/lib/ruby/2.6.0/psych.rb:577:in `initialize': Is a directory @ io_fillbuf - fd:5 /etc/transmission-rss.conf (Errno::EISDIR)

And when I went to check if the transmission-rss.conf file had been created a directory with the same name was created in its place.

I have to run the docker-compose up command using sudo so I don't know if this has anything to do with permissions.

Here is my current docker-compose.yml file:

version: '3'
services:
  portainer:
    container_name: portainer
    image: portainer/portainer
    volumes:
      - '/home/miguel/docker/portainer/data/:/data'
      - '/home/miguel/docker/portainer/socket/:/var/run/docker.sock'
    ports:
      - "9000:9000"
    restart: always
  transmission-rss:
    container_name: transmission-rss
    image: nning2/transmission-rss:latest
    volumes:
      - '/home/miguel/docker/transmission-rss/transmission-rss.conf/:/etc/transmission-rss.conf/'
    restart: unless-stopped

The portainer container starts fine.

Thank you very much, Miguel

Answer 1

make sure that files exist in both side (inside host machine and inside container).

if one of them not exist then docker create a directory instead of a file

Answer 2

- '/home/miguel/docker/transmission-rss/transmission-rss.conf/:/etc/transmission-rss.conf/'

Please remove the trailing slashes (there are 2x!) and ensure transmission-rss.conf is a file and not a dir on your host source :).

To be slightly more comprehensive:

1. Follow this to avoid having to use sudo with docker-compose: https://docs.docker.com/install/linux/linux-postinstall ( this is not the cause of your issue , but it is annoying to have to preface every command with sudo, basically just need to add your user to the docker group)
2. Update docker-compose.yml , remove the trailing slashes from source and target for transmission-rss.conf
3. Remove your existing volumes ( docker volume ls + docker volume rm volume_name ) after backing up your data if needed
4. On your 'host' (machine you are running the docker-compose commands from), make sure the file exists, and is not a directory
5. docker-compose down
6. docker-compose build
7. docker-compose up

Let me know if it is still incorrectly being created as a dir, thank you.