How to share file from docker container to host

Question

I have a docker container which is running fine. It generates a few files in the directory /Project/userfiles.txt. I need these files for some testing purpose. But when this container is stopped everything is deleted. So I need to copy this file from the container to host.

I have a python application running in the container which is generating the file. I want some command or any way through which I can send the userfiles.txt to host at the end when the container is stopped.

To do this I can use docker cp command and I tried it but it gave me an error docker not found as docker is not installed.

How can I share files from container to host?

Answer 1

Use a volume (a bind mount one) to make sure the files written in /Project are persisted.

That means you need to docker run your image with a -v /host/path:/Project option.
See "Use bind mounts" for the simplest approach (which is to share a host folder with your container)