How to define array/object in .env file?

Question

The following is my Javascript object:

window.options = {
    VAR1: VAL1,
    VAR2: VAL2,
    VA31: VAL3,
};

I want it (either object or array) to be defined in a .env file. How can I do that?

Answer 1

value in .env value can only be string.

Simple workaround is to just store the env value as a comma separated value, like:

SOME_VAR=VAL1,VAL2,VAL3

and split it on your js file:

const someVar = process.env.SOME_VAR.split(",");

console.log(someVar); // [ 'VAL1', 'VAL2', 'VAL3' ]

Or use whatever delimiter you want.

---

If you want to store object, (unclean) workaround is to store JSON string as the env value, for example

OBJECT_VAL={ "VAR1": "VAL1", "VAR2": "VAL2", "VA31": "VAL3" }

and on your js code, you can parse the JSON:

const objectVal= JSON.parse(process.env.OBJECT_VAL);
console.log(objectVal); // { VAR1: 'VAL1', VAR2: 'VAL2', VA31: 'VAL3' }

---

I personally don't think storing JSON string inside .env is a good idea, so I would like to give my recommendation on better way to store .env value and use it on your js code.

1. Store env with normal string value, or delimiter separated value

For example:

ARRAY=VAL1,VAL2,VAL3

VAR1=VALl1
VAR2=VALl2
VAR3=VALl3

2. Make a js file to handle env variable

I will call it env.js, and on this file I will export object containing all env variable

module.exports = {
    array: process.env.ARRAY.split(","),
    object: {
       var1: process.env.VAR1,
       var2: process.env.VAR2,
       var3: process.env.VAR3,
    }
}

And on other file, you can just import env.js and call the env value

const env = require("path/to/env.js");

console.log(env.array); // [ 'VAL1', 'VAL2', 'VAL3' ]
console.log(env.object.var1); // "VAL1"

If your project often call process.env, this solution might make your code a bit cleaner since you don't need to call process. everytime you want to access your env variable.

Answer 2

Two ways you can define an array in an .env file they are

1. // In the .env file:
   SOME_ARRAY = A , B ,C
   

2. //In the .env file: 
   SOME_ARRAY = '["A","B","C"]'
   

// In the code: 
const convertedArray = JSON.parse(process.env.SOME_ARRAY)

In order to covert objects, unfortunately, objects are not supported in .env files because they do not understand anything other than strings, but we can keep an object in JSON format and then we can parse it in our folder where ever we want

MY_OBJECT = { "A":"One","B":"two","C":"three" } 

//we can access it in our code by follows 
const myObject = JSON.parse(process.env.MY_OBJECT)

//we can also access a certain property of that object like follows
const myObject = (JSON.parse(process.env.MY_OBJECT)).A   

Answer 3

Try this out, in.env file store

OBJ='{"alpha":"1","beta":"2"}'

like this, you can easily parse it to an object:

let obj=JSON.parse(process.env.OBJ)
console.log(obj.alpha)