rollup-plugin-variables

0.1.1 verified Mon Apr 27 auth: no javascript maintenance

A Rollup plugin that replaces custom markers (e.g., [[VARIABLE]]) in source files with values from a separate variables file (JS, JSON, or TXT). Stable version 0.1.1. Low activity; last release in 2019. Key differentiator: allows externalizing environment-specific values without a full-fledged env replacement plugin. Limited to rollup.

Common errors

error Error: Cannot find module './env.js' ↓

cause Variables file path is resolved relative to rollup.config.js; file missing or incorrect.

fix

Ensure env.js exists in the same directory as rollup.config.js or provide absolute path via fileName option.

error TypeError: variables is not a function ↓

cause Using named import { variables } instead of default import.

fix

Use default import: import variables from 'rollup-plugin-variables'.

error The marker format 'invalid' is not supported. ↓

cause Marker option string or function must return a valid format like '[[]]' or '{{}}'.

fix

Use supported marker format: '[[]]', '{{}}', or another string with matching brackets.

Warnings

gotcha Default marker is [[]]; double brackets required. ↓

fix Ensure source files use [[VARIABLE_NAME]] syntax, or configure marker option.

gotcha Variables file must export an object (module.exports = ...) when format is 'js'. ↓

fix Use module.exports = { KEY: 'value' } in .js file; for .json use JSON object directly.

deprecated Plugin is in maintenance mode; no updates expected. ↓

fix Consider migrating to @rollup/plugin-replace or similar.

gotcha Nested markers (e.g., [[[VAR]]]) not supported; will cause undefined replacement. ↓

fix Use flat variable names without nested brackets.

Install

npm install rollup-plugin-variables

yarn add rollup-plugin-variables

pnpm add rollup-plugin-variables

Imports

default

wrong

const variables = require('rollup-plugin-variables')

correct

import variables from 'rollup-plugin-variables'

ESM default import is only supported; CommonJS require may work if using a bundler

variables

wrong

import { variables } from 'rollup-plugin-variables'

correct

import variables from 'rollup-plugin-variables'

Named export does not exist; use default import

None (type import)

import type { RollupOptions } from 'rollup'; import variables from 'rollup-plugin-variables';

No dedicated type exports; types inferred from Rollup

Quickstart

Configures Rollup to replace [[variables]] with values from env.js during build.

// rollup.config.js
import variables from 'rollup-plugin-variables';

export default {
  input: 'src/index.js',
  output: {
    file: 'dist/bundle.js',
    format: 'iife'
  },
  plugins: [
    variables({
      fileName: 'env.js',
      format: 'js',
      marker: '[[]]'
    })
  ]
};