Copying files to a container with Docker Compose

Question

I have a Dockerfile where I copy an existing directory (with content) to the container which works fine:

Dockerfile

FRO         


        

Answer 1

Given

    volumes:
      - /dir/on/host:/var/www/html

if /dir/on/host doesn't exist, it is created on the host and the empty content is mounted in the container at /var/www/html. Whatever content you had before in /var/www/html inside the container is inaccessible, until you unmount the volume; the new mount is hiding the old content.