Env Variables

The plugin exposes env variables on the special import.meta.env object.

Config

const env = require("rollup-plugin-import-meta-env");

env({
    PROD: true,
    DEV: false
})

Before

console.log(import.meta.env.DEV);

After

console.log(false);

Remove unuse variables by tree-shaking.

To prevent accidentally leaking env variables to the client, it is therefore recommend to always reference them using the full static string. For example, dynamic key access will not recommend.

DB_PASSWORD=foobar
VITE_SOME_KEY=123

Before

// GOOD
console.log(import.meta.env.VITE_SOME_KEY);

After

// GOOD
console.log("123");

Before

// BAD
var env=import.meta.env;
console.log(env.VITE_SOME_KEY);

After

// BAD
var env={
	DB_PASSWORD: "foobar",
	VITE_SOME_KEY: "123"
};
console.log(env.VITE_SOME_KEY);

Filter exposed variables

To prevent accidentally leaking env variables to the client, config function to filter exposed variables. Only variables prefixed with VITE_ are exposed by e.g. the following config.

env(Object.fromEntries(
    Object.entries(process.env).filter(([key, value]) => {
        if(!(/^[a-zA-Z_$][a-zA-Z0-9_$]*$/.test(key))) {
            return false;
        }
        return key.startsWith("VITE_");
    })
))

Other Options

• include
• exclude
• sourcemap