Allow tmp dir overriding

[johnallen3d]

Currently the temporary directory used by the "history" feature of nib is hard-coded (as /tmp/nib/config). This works great for the default installation of Docker for Mac as this directory is available to volume mount. However for alternative Docker on Mac solutions (e.g. Colima) this is not always the case. Consider allowing the user to specify an alternative location (or perhaps disable this feature 😱).

[johnallen3d]

This report was based on an inaccurate assumption. 🤦‍♂️ I did have an issue related to running Docker in Colima but it has to do with env_file and the fact that we augment existing docker-compose.yml (injecting a volume to persist history). When we do this we use docker-compose config to get the existing configuration in a consistent form, inject volume configuration and then write a temporary compose file to a temporary directory.

When I set up Colima I configured it to create a mount point with my "development directory" (e.g. where I store source code). For me this looks like:

vm:
  mounts:
    - /Users/johna/development:w
  ...

However when Nib creates a temporary compose file it is written to and executed from a system temp directory (for me, on macOS it's /var/folders/...).

Interestingly, the docker-compose config command will expand most paths but will not automatically for env_file paths.

❯ cat docker-compose.yml
version: "2"
services:
  gem:
    build:
      context: .
    env_file:
      - secrets.foo

❯ docker-compose config
services:
  gem:
    build:
      context: /Users/johna/development/technekes/src/gems/incent-gem
      dockerfile: Dockerfile
    env_file:
    - secrets.foo
    networks:
      default: null
networks:
  default:
    name: incent-gem_default

It works fine if I prefix env_file with $PWD the path is expanded and everything works.

❯ cat docker-compose.yml
version: "2"
services:
  gem:
    build:
      context: .
    env_file:
      - $PWD/secrets.foo

❯ docker-compose config
services:
  gem:
    build:
      context: /Users/johna/development/technekes/src/gems/incent-gem
      dockerfile: Dockerfile
    env_file:
    - /Users/johna/development/technekes/src/gems/incent-gem/secrets.foo
    networks:
      default: null
networks:
  default:
    name: incent-gem_default

... but it's not ideal to change project configuration because some users are using an alternative Docker host.

I was able to workaround this issue by also creating a mount for /var/folders in my Colima configuration.

vm:
  mounts:
    - /Users/johna/development:w
    - /var/folders/:w
  ...

EDIT: turns out this 👆 was not a solution. When I tested the change to Colima I still had $PWD/secrets.foo in my docker-compose.yml. 🤦‍♂️

[johnallen3d]

It turns out that when you brew install docker-compose you get the v2 version (Go based Docker plugin). There are some slight differences between v2 and v1 (Python implementation) and one of those is the output of docker-compose config. For now, I have downgraded to v1 and am back in business.

Re-opening this because other users will, at some point, be upgrading to v2 as well.