[Feature] Docker Secrets Implementation

[TheSpartan18k]

What’s the feature?

Enable Docker Secrets for sensitive variables like OIDC_CLIENT_SECRET

Why is it useful?

Add the ability to use _FILE to mount sensitive environment variables as docker secrets. Below is a script that I use for other containers and is based off of the official MariaDB/Postgres entrypoint.

Example: OIDC_CLIENT_SECRET_FILE: "/run/secrets/tugtainer_client_secret

#!/bin/sh

set -eu

file_env() {
  var="$1"
  fileVar="${var}_FILE"
  varValue="$(printenv "$var" 2>/dev/null || true)"
  fileVarValue="$(printenv "$fileVar" 2>/dev/null || true)"
  if [ -n "$varValue" ] && [ -n "$fileVarValue" ]; then
    echo "Both $var and $fileVar are set (but are exclusive)" >&2
    exit 1
  fi
  if [ -n "$fileVarValue" ]; then
    [ -f "$fileVarValue" ] || {
      echo "Secret file not readable: $fileVarValue" >&2
      exit 1
    }
    export "$var"="$(cat "$fileVarValue")"
    unset "$fileVar"
  fi
}

for var in \
  AGENT_SECRET \
  OIDC_CLIENT_ID \
  OIDC_CLIENT_SECRET
do
  file_env "$var"
done

[ $# -gt 0 ] || { echo "Error: no command provided to exec" >&2; exit 1; }
exec "$@"

Any extra thoughts?

No response