process.env does not expose its keys as expected

[jobi]

I'm not sure if this is expected, but it doesn't feel right.

If I run an app with

$ REACT_APP_FOO=bar npm start

I can access process.env.REACT_APP_FOO, but REACT_APP_FOO in process.env returns false, and process.env["REACT_APP_FOO"] is undefined.

I'm trying to have something like:

function getConfig(key) {
   if (key in process.env) {
     return process.env[key];
   }

   return defaults[key];
}

[tbillington]

If it's not there it will be undefined, your could write it like this.

function getConfig(key) {
   return process.env[key] || defaults[key];
}

[gaearon]

I think this might be possible to fix if we use

new DefinePlugin({
  'process.env': {
    NODE_ENV: ...,
    OTHER_VAR: ...,
    // ...
  }
})

form instead of

new DefinePlugin({
  'process.env.NODE_ENV': ...,
  'process.env.OTHER_VAR': ...,
  // ...
})

like we do now.

Would you like to give it a try and maybe submit a PR?

The relevant code is in packages/react-scripts/config/env.js.
(It gets imported from webpack configs in packages/react-scripts/config.)

The contributing instructions are here.

[thien-do]

Hey @gaearon I can do this.

[thien-do]

Please check the PR above. I hope it is what you explained

[gaearon]

Fixed in #807.

[mars]

This is amazing to find already merged!

I've been working on a solution for the env vars issue on the Heroku buildpack. The ability to enumerate process.env entries will directly contribute to that solution 😄🍻

[fson]

This is going to be included in 0.7.0, which will be out soon.