Command line Flag to specify the Docker Daemon data directory

[jetlime]

Act version

0.2.56

Feature description

As the docker images that ACT pull are quite voluminous it would be helpful to define in which data directory the docker daemon shall store its files.

For example, If I would like to store all act related files to an external media (because the docker images I use normally I quite smaller), I need to modify the configuration of the dockerd as follows,

I either need to temporarly modify the data-root parameter of dockerd to the external media, by running this command simultaneously in another shell.

mkdir /media/user/external-media/docker-data/
/usr/bin/dockerd --data-root /media/user/external-media/docker-data/

Otherwise I could, as defined in this doc, I could modify the data-root parameter in the daemon.json config file,

{
  "data-root": "/media/user/external-media/docker-data"
}

It would be very useful if as a user, I could specify the dockerd data-root with a CLI flag, e.g, act --data-root /media/user/external-media/