rollup/rollup-plugin-node-resolve

README

Moved

This module has moved and is now available at @rollup/plugin-node-resolve. Please update your dependencies. This repository is no longer maintained.

rollup-plugin-node-resolve

This plugin used to be called rollup-plugin-npm

Locate modules using the Node resolution algorithm, for using third party modules in node_modules

Installation

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

Usage

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

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

      // the fields to scan in a package.json to determine the entry point
      // if this list contains "browser", overrides specified in "pkg.browser"
      // will be used
      mainFields: ['module', 'main'], // Default: ['module', 'main']

      // DEPRECATED: use "mainFields" instead
      // use "module" field for ES6 module if possible
      module: true, // Default: true

      // DEPRECATED: use "mainFields" instead
      // use "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
      jsnext: true,  // Default: false

      // DEPRECATED: use "mainFields" instead
      // use "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
      main: true,  // Default: true

      // some package.json files have a "browser" field which specifies
      // alternative files to load for people bundling for the browser. If
      // that's you, either use this option or add "browser" to the
      // "mainfields" option, otherwise pkg.browser will be ignored
      browser: true,  // Default: false

      // not all files you want to resolve are .js files
      extensions: [ '.mjs', '.js', '.jsx', '.json' ],  // Default: [ '.mjs', '.js', '.json', '.node' ]

      // whether to prefer built-in modules (e.g. `fs`, `path`) or
      // local ones with the same names
      preferBuiltins: false,  // Default: true

      // Lock the module search in this path (like a chroot). Module defined
      // outside this path will be marked as external
      jail: '/my/jail/path', // Default: '/'

      // Set to an array of strings and/or regexps to lock the module search
      // to modules that match at least one entry. Modules not matching any
      // entry will be marked as external
      only: [ 'some_module', /^@some_scope\/.*$/ ], // Default: null

      // If true, inspect resolved files to check that they are
      // ES2015 modules
      modulesOnly: true, // Default: false

      // 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: [ 'react', 'react-dom' ], // Default: []

      // Any additional options that should be passed through
      // to node-resolve
      customResolveOptions: {
        moduleDirectory: 'js_modules'
      }
    })
  ]
};

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: ...
})

Additional Plugin APIs

In addition to the standard hooks used by Rollup, this plugin exposes additional functionality useful for other plugins.

getPackageInfoForId (moduleId: string) => PackageInfo

Returns an object with metadata about the package containing the specified module. PackageInfo has the following fields:

packageJson: The package.json file for the package
packageJsonPath: The path to the package.json file
root: The root directory of the package
resolvedMainField: Which main field was used during resolution (see the mainFields option)
browserMappedMain: Whether the browser map was used to resolve the module's entry point
resolvedEntrypoint: The resolved entry point to the module with respect to the mainFields configuration and browser mappings.

This object is populated during the resolve hook, so plugins should only depend on this information being present in hooks that run after resolve.

Usage from Other Plugins

getPackageInfoForId is exposed as a method on the plugin object along side the other hooks expected of a Rollup plugin.

import resolve from 'rollup-plugin-node-resolve';
const resolve = resolve();

export default ({
  input: ...,
  plugins: [
    resolve(),
    // custom plugin
    {
      transform(code, id) {
        // get package info for this module id
        const info = resolve.getPackageInfoForId(id);

        // if it's the buffer shim, return nothing.
        if (info.packageJson.name === 'buffer') {
          return '';
        }

        return code;
      }
    }
  ],
  output: ...
})

If you're writing a standalone plugin, you can get access to the plugin object by pulling it out of the config provided to the buildStart hook:

export default function {
  let nodeResolvePlugin;

  function getPackageInfoForId(id) {
    // user config isn't using this plugin
    if (!nodeResolvePlugin) return;

    // user config has an older version without this API
    if (!nodeResolvePlugin.getPackageInfoForId) return;

    return nodeResolvePlugin.getPackageInfoForId(id);
  }

  return {
    buildStart (options) {
      nodeResolvePlugin = options.plugins && options.plugins.filter(p => p.name === 'node-resolve')[0];
    },
    transform (code, id) {
      const info = getPackageInfoForId(id);
      // ...
    }
  }
}

License

MIT