If you use the super useful node-config module, it can be a helpful solution for you.
node-config-examiner will show you all the differences between the default (default.json) configuration and the one with which you launched your nodejs application with NODE_ENV or NODE_CONFIG_ENV.
npm install node-config-examiner --dev
yarn add node-config-examiner --dev
Now open your main script and call the examinate method from node-config-examiner module.
const examiner = ;examiner;
By default it will output the result with old schoold console.log but if you want, you can simply attache your favorite logger (e.g. winston):
const examiner = ;const winston = ;examiner;
May be freely distributed under the MIT license.