@rollup/plugin-node-resolve

🍣 A Rollup plugin which locates modules using the Node resolution algorithm, for using third party modules in node_modules

Requirements

This plugin requires an LTS Node version (v8.0.0+) and Rollup v1.20.0+.

Install

Using npm:

npm install @rollup/plugin-node-resolve --save-dev

Usage

Create a rollup.config.js configuration file and import the plugin:

import resolve from '@rollup/plugin-node-resolve';

export default {
  input: 'src/index.js',
  output: {
    dir: 'output',
    format: 'cjs'
  },
  plugins: [resolve()]
};

Then call rollup either via the CLI or the API.

Options

mainFields

Type: Array[...String]
Default: ['module', 'main']
Valid values: ['browser', 'jsnext', 'module', 'main']

Specifies the properties to scan within a package.json, used to determine the bundle entry point. The order of property names is significant, as the first-found property is used as the resolved entry point. If the array contains 'browser', key/values specified in the package.json browser property will be used.

module

DEPRECATED: use "mainFields" instead

Use pkg.module field for ES6 module if possible. This option takes precedence over both "jsnext" and "main" in the list if such are present.

jsnext

DEPRECATED: use "mainFields" instead

Use pkg['jsnext:main'] if possible, legacy field pointing to ES6 module in third-party libraries, deprecated in favor of pkg.module, see: https://github.com/rollup/rollup/wiki/pkg.module. This option takes precedence over "main" in the list if such is present.

main

DEPRECATED: use "mainFields" instead

Use pkg.main field or index.js, even if it's not an ES6 module (needs to be converted from CommonJS to ES6), see https://github.com/rollup/rollup-plugin-commonjs.

browser

Type: Boolean
Default: false

If true, instructs the plugin to use the "browser" property in package.json files to specify alternative files to load for bundling. This is useful when bundling for a browser environment. Alternatively, a value of 'browser' can be added to the mainFields option. If false, any "browser" properties in package files will be ignored. This option takes precedence over mainFields.

extensions

Type: Array[...String]
Default: ['.mjs', '.js', '.json', '.node']

Resolve extensions other than .js in the order specified.

preferBuiltins

Type: Boolean
Default: true

Whether to prefer built-in modules (e.g. fs, path) or local ones with the same names

jail

Type: String
Default: '/'

Lock the module search in this path (like a chroot). Modules defined outside this path will be marked as external.

only

Type: Array[...String|RegExp]
Default: null

Example: only: ['some_module', /^@some_scope\/.*$/]

modulesOnly

Type: Boolean
Default: false

If true, inspect resolved files to check that they are ES2015 modules.

dedupe

Type: Array[...String]
Default: []

Force resolving for these modules to root's node_modules that helps to prevent bundling the same package multiple times if package is imported from dependencies.

dedupe: [ 'my-package', '@namespace/my-package' ]

This will deduplicate bare imports such as:

import 'my-package';
import '@namespace/my-package';

And it will deduplicate deep imports such as:

import 'my-package/foo.js';
import '@namespace/my-package/bar.js';

customResolveOptions

Type: Boolean
Default: null

Any additional options that should be passed through to node-resolve.

customResolveOptions: {
  moduleDirectory: 'js_modules'
}

rootDir

Type: String
Default: process.cwd()

Root directory to resolve modules from. Used when resolving entrypoint imports, and when resolving deduplicated modules. Useful when executing rollup in a package of a monorepository.

// Set the root directory to be the parent folder
rootDir: path.join(process.cwd(), '..')

Using with @rollup/plugin-commonjs

Since most packages in your node_modules folder are probably legacy CommonJS rather than JavaScript modules, you may need to use @rollup/plugin-commonjs:

// rollup.config.js
import resolve from '@rollup/plugin-node-resolve';
import commonjs from '@rollup/plugin-commonjs';

export default {
  input: 'main.js',
  output: {
    file: 'bundle.js',
    format: 'iife',
    name: 'MyModule'
  },
  plugins: [resolve(), commonjs()]
};

Resolving Built-Ins (like fs)

This plugin won't resolve any builtins (e.g. fs). If you need to resolve builtins you can install local modules and set preferBuiltins to false, or install a plugin like rollup-plugin-node-builtins which provides stubbed versions of these methods.

If you want to silence warnings about builtins, you can add the list of builtins to the externals option; like so:

import resolve from '@rollup/plugin-node-resolve';
import builtins from 'builtin-modules'
export default ({
  input: ...,
  plugins: [resolve()],
  external: builtins,
  output: ...
})

Meta

CONTRIBUTING

LICENSE (MIT)