Docker COPY from ubuntu absolute path
The absolute path of your resources refers to an absolute path within the build context, not an absolute path on the host. So all the resources must be copied into the directory where you run the docker build and then provide the path of those resources within your Dockerfiles before building the image. (This refers to the location where you run your Dockerfile)
There is a closed issue for this as well.
You can't. You have to copy/hardlink the files/folders inside the directory where you build the docker image.