BORG_PASSPHRASE_FILE does not set BORG_PASSPHRASE environment variable

[valfur03]

I have the following borgmatic service in my compose.yaml file:

services:
  borgmatic:
    image: ghcr.io/borgmatic-collective/borgmatic:1.8.10
    environment:
      # BORG_PASSPHRASE: 'heremypassphrase'
      BORG_PASSPHRASE_FILE: /run/secrets/BORGMATIC_ENCRYPTION_PASSPHRASE
    volumes:
      - borg-config:/root/.config/borg
      - ./borgmatic/config:/etc/borgmatic.d:ro
      - /backup/borg/docker:/backup
    secrets:
      - BORGMATIC_ENCRYPTION_PASSPHRASE
    restart: unless-stopped

When using the BORGMATIC_PASSPHRASE_FILE, the BORGMATIC_PASSPHRASE is not set inside the container. Initializing repositories or creating archives also asks for my passphrase.

$ docker compose exec borgmatic borgmatic create --verbosity 1 --stats --list
local: Creating archive
Enter passphrase for key /backup/repo:

However, BORGMATIC_PASSPHRASE works as expected when passed as is to the container. It seems that the _FILE variable is not working in my case.

The logs still print this message when starting up:

Setting BORG_PASSPHRASE from the content of /run/secrets/BORGMATIC_ENCRYPTION_PASSPHRASE
Unsetting BORG_PASSPHRASE_FILE

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OS: Fedora Linux version 38 (Server Edition)
Docker version: Docker version 25.0.2, build 29cf629
Compose version: Docker Compose version v2.24.5

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This issue might be related to #320.

[valfur03]

After taking a look at the docker entrypoint, I realized my mistake.

The environment variable is meant to be used by crond, not subprocesses like docker compose exec ....