Node: Native support for loading environment variables

[itaied246]

Node based apps are working great with environment variables.
It is simple to modify the dynamic values based on the app purpose.
But when it comes to development environment I find it is coming short.

For example, for test and production environments,
my configuration file can be the same,
and read the variables from the automated building tool environment (gitlab-runner, travis ...).

But for the development phase, running on the local machine of the developers,
we want the developers to easily modify the values (like port, dbUrl ...).

dotenv is a great try, but you have to install it as a dependency,
though it's actually a devDependency.
I don't want to have something like this in my production app:

if (process.env.NODE_ENV != PRODUCTION)
    dotenv.config();

And while you could argue that I can remove the if statement,
my application still depends on the library.

I think it could be great if the platform (node) could have load the environment variables (like docker does).

And so my package.json would look something like this:

"start": "node build/index.js",
"start:dev": "node --env-file=env-vars.json build/index.js"

Developers now can easily commit and modify the env-vars.json,
and the environments are still provide great agility.

What do you guys think?

[mscdex]

-1 IMO this is best left to userland.

[Trott]

@itaied246 How would this work? Would npm start consult the NODE_ENV environment variable and choose between the start and start:dev tasks?

[devsnek]

@Trott he's talking about --env-file=env-vars.json

[Trott]

@Trott he's talking about --env-file=env-vars.json

Oh, I see, adding that as a CLI flag. Got it.

[devsnek]

I feel like this solves the problem

[itaied246]

@devsnek you are right, that'll do it.
But I still think that executing the environment with a file is necessary.
You didn't provide any reason to not implement it, so why do you suggest alternatives?

[itaied246]

Another thing came up to my mind is that exporting the env vars does change your desktop environment,
as opposed to dotenv and my suggestion.

[targos]

It's possible to use dotenv without polluting your production code. You can for example use Node's preload feature:

// env.js
require('dotenv').config();

and have in your package.json:

"start:dev": "node -r ./env.js build/index.js

It's not much more complicated than your suggestion and allows to do any kind of customization (like setting the env from a JSON file).

I also think this is best left to userland.

[itaied246]

You are right, this is much more elegant solution.
For now I think I'll use this, though I my opinion it could be awesome to enable more advanced options for running in the platform.

[cjihrig]

I agree with @targos as well. I'll close this out given the general sentiment to defer to userland.