Any downside for mounting the drive root as temporary?

Drone Support
1

I’ve began using those nifty temporary volumes, with PHP the modules and such lie in many different directories.

So my question is: Is it smart/stupid/inefficient to mount the drive root temporarily?

The major issue is I do not know which files are used by the hundreds of dependencies I have to install.

steps:
- name: Install Stuff
  image: debian:buster
  volumes:
  - name: root
    path: /
  commands:
  - apt-get update
  - apt-get install somelibrary

- name: Use Stuff
  image: debian:buster
  volumes:
  - name: root
    path: /
  commands:
  - some_executable

volumes:
- name: root
  temp: {}
2

If you mount the root directory, you would override the contents of the debian:buster image, and you would be left with an empty os. Instead of trying to mount a volume to share apt packages, we would generally recommend building and publishing an image to dockerhub with everything you need installed, and then using that image in your yaml.

3

I see thanks! Did not know that the temporary volume overwrites. Thought it would create a bridge between the steps.

4

It does create a bridge in between steps and can be useful for sharing state between steps [1], however, when you mount a volume you effectively overwrite the original contents of the target mount path. If you overwrite the root directory, you effectively overwrite the entire docker image, resulting in an empty image.

[1] https://docs.drone.io/pipeline/docker/examples/languages/golang/#dependencies