Node JS Bootstrap Run Environment w/ run script that can inject secret env vars locally or into Docker or Kubernetes

docker-compose.yml

version: '3'
services:
  webapp:
    container_name: webapp
    build: .
    volumes:
      - .:/opt/app
    ports:
      - 8080:8080
      - 5858:5858
    env_file:
      - ./secrets.env
    restart: always

Dockerfile

# NodeJS v6 official image
FROM node:boron

EXPOSE 8080
EXPOSE 9229

WORKDIR /opt/app

RUN npm install -g node-sass grunt grunt-cli grunt-sass

COPY . /opt/app/.

RUN npm install
RUN grunt sass
RUN grunt concat

# RUN CONTAINER
ENV DOCKER true
RUN chmod +x /opt/app/run.sh
CMD ["/opt/app/run.sh"]

run.sh

#!/bin/bash

HOME_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )" # get the relative path to the script's dir

function injectSecrets {
    # Inject secrets.env into env and run the application
    if [ -f "${HOME_DIR}/secrets.env" ]; then

        while IFS='' read -r line || [[ -n "$line" ]]; do
            splitLine=(${line//=/ })
            echo "Loading env var ${splitLine[0]}..."
            eval "export ${line}"
        done < "${HOME_DIR}/secrets.env"

    fi
}

function main {
    if ! [[ -z "${DOCKER}" ]]; then
        # if script is executed inside docker container cd into target app path first
        echo "Loading Docker profile..."
        cd /opt/app
    else
        # script is running locally/natively without docker so secrets need to added to env manually
        echo "Loading native/local profile..."
        injectSecrets
    fi

    if [ "$NODE_ENV" = "dev" ]; then
        eval "npm run-script debug"
    else
        eval "npm start"
    fi
}

main

secrets.env.example

NODE_ENV="dev" # or prod
SERVER_PORT=8080
AUTHOR=""
SITE_NAME=""
FB_APP_ID=""
GS_TRACKING_ID=""
GA_TRACKING_ID=""
GM_API_KEY=""
APP_URL_DOMAIN=""
MAILGUN_API_KEY=""
MAILGUN_DOMAIN=""
SALES_EMAIL=""
SUPPORT_EMAIL=""