docker 支持使用 ENV_FILE 环境变量

docker-entrypoint.sh

#!/usr/bin/env bash

# set -v
set -e

file_env() {
  local var="$1"
  local fileVar="${var}_FILE"
  local def="${2:-}"

  if [ "${!var:-}" ] && [ "${!fileVar:-}" ]; then
    echo >&2 "error: both $var and $fileVar are set (but are exclusive)"
    exit 1
  fi
  local val="$def"
  if [ "${!var:-}" ]; then
    val="${!var}"
  elif [ "${!fileVar:-}" ]; then
    val="$(< "${!fileVar}")"
  fi
  export "$var"="$val"
  unset "$fileVar"
}

docker_setup_env() {
  file_env "DATABASE_USERNAME"
  file_env "DATABASE_PASSWORD"
}

docker_setup_env

exec /opt/datadata/_datadata "$@"