Node app deployed on Heroku only has a few env vars, and none of the ones specified by config-CodePudding

I am trying to deploy a React app on heroku and even though I have multiple environment variables set in heroku's config, none of them are appearing at run time. I added a console.log(process.env) to my app and the output was this:

FAST_REFRESH: true
NODE_ENV: "production"
PUBLIC_URL: ""
WDS_SOCKET_HOST: undefined
WDS_SOCKET_PATH: undefined
WDS_SOCKET_PORT: undefined

My heroku config is this:

BACKEND_URL:          https://lz-comparables-manager-be-stg.herokuapp.com/
NODE_ENV:             staging
NODE_OPTIONS:         --max_old_space_size=1024
SKIP_PREFLIGHT_CHECK: true

How come none of those variables (or any of the other normal env vars of a Node app) are showing up in the app?

CodePudding user response：

The prefix REACT_APP_ is necessary when accessing env variables, try

{process.env.REACT_APP_SOMETHING}

Also should you write prefix when define.

https://create-react-app.dev/docs/adding-custom-environment-variables/