如何将文件从 docker 图像移动到计算机上的文件夹中

Question

I'm building a docker image which I need to copy a file added to the image into a write-protected location on a Linux machine (/opt).

so far I have tried doing this by adding the file to the docker image and then using a cp command to move it into /opt as shown below:

FROM ubuntu:latest
ADD test.txt / 
CMD ["cp", "./test.txt", '/opt']

this doesn't work at all even when trying to move the file just into the desktop so I would appreciate at explanation about how to do it properly.

Answer 1

It looks like you need to share a volume between the container and the host.

If that is the case probably your best approach is to create a docker compose file, similar to the one below.

---
version: "3.3"
services:
  fileserver:
    image: "your-docker-image"
    volumes:
      - /opt

You can find more information in here