Run npm script with environment variable from package.json

Question

I am using a specific task runner to execute my node scripts called Yoshi. I want to run a script from package.json, for example, yoshi test but with a custom environment variable (for example special_variable):

"scripts": {
    "start": "yoshi start", 
    "test":  "special_variable=value yoshi test // this case"
}

Possible duplicate of [How to set Environment variables from within package.json \[Node.js\]](https://stackoverflow.com/questions/25112510/how-to-set-environment-variables-from-within-package-json-node-js) — RobC, Jun 26 '18 at 09:28
They are explicitly speaking about the NODE_ENV variable and not a custom one... — Technotronic, Jun 26 '18 at 11:39
The solution in the linked answer equally applies to custom variables too. E.g. `FOO=bar` - I fail to see what makes your variable any more _special_ than `NODE_ENV`? If you're using a Bash shell you can check this by using [`printenv`](https://ss64.com/bash/printenv.html) in an _npm-script_. For instance: `"list-env-vars" : "FOO=bar printenv"`, then run `npm run list-env-vars` and you'll see `FOO=bar` listed as an env variable. — RobC, Jun 26 '18 at 12:50
Weird, I tried it before and it didn't work, but now, looks like you are right. I'm closing this one. — Technotronic, Jun 27 '18 at 10:31

score 3 · Answer 1 · edited Feb 12 '19 at 13:22

3

Apparently, I can pass an environment variable using the ENV prefix in my npm-script like this:

"scripts": {
    "start": "yoshi start", 
    "test":  "ENV special_variable=value yoshi test"
}

edited Feb 12 '19 at 13:22

RobC

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answered Jun 24 '18 at 16:24

Technotronic

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score 2 · Answer 2 · answered Jun 24 '18 at 16:42

2

I think you can create .env file and add your variables there.

answered Jun 24 '18 at 16:42

Aliaksandr Sushkevich

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Run npm script with environment variable from package.json

2 Answers2