docker-volume-plugin-helloworld

A Hello world Docker Volume Plugin, that shows how to write a simple Docker Volume Plugin.

Look at fordemo.js for a very simple (not practical) volume plugin, only for demonstration purposes.

The app.js is a more complete Volume Plugin, that uses SSHFS for underlying filesystem, instantied from Docker through the Volume Plugin.

How to setup

• Create a file helloworld.json and place it in /etc/docker/plugins

{
    "Name": "plugin-helloworld",
    "Addr": "http://localhost:7010"
}

• Install SSHFS

sudo apt-get install sshfs

• Download this volume plugin and start it

git clone https://github.com/rsmoorthy/docker-volume-plugin-helloworld.git
cd docker-volume-plugin-helloworld
npm install .
node app.js

• Now start a docker container, and use this volume-plugin

docker run --rm -v "ssh-//user@passwd-host/":/data \
        --volume-driver=helloworld busybox ls -l /data

• Mount in one container and share it with others. Note that the first container needs to be started, for other containers to access the files

docker run -d --name first -v "ssh-//user@passwd-host/":/data \
        --volume-driver=helloworld ubuntu

docker start first
docker run --rm --volumes-from first busybox ls -l /data
# Shows the remote files
docker stop first
docker run --rm --volumes-from first busybox ls -l /data
# Empty files

• Unmount Issues

Please refer to Unmount Issues for an explanation of the problem faced during the Docker Meetup.