Webpack Upgrade - Module not found: Can't resolve node_modules

Question

I'm currently working on a upgrade from Webpack 1 to 2, and then to 3. Within this upgrade, I've adhered to the migration instructions as per the instructions for 1 => 2 and for 2 => 3.

The issue I'm having is that none of the installed packages within my node_modules seem to be getting resolved within my code inside client/app/bundles. The error I'm getting for all the node_modules are in the following structure:

ERROR in ./node_modules/alt/lib/store/StoreMixin.js || Module not found: Error: Can't resolve 'transmitter' in 'client/node_modules/alt/lib/store'

My theory is that somewhere I have a mismatch on the file-loader, expose-loader, or imports-loader versions since it makes sense that without the proper versions, the modules wouldn't get imported. I've ensured that all the module.rules have loaders that end in the -loader pattern. yarn install also succeeds without errors.

My dependencies and Webpack configurations are as follows:

Package.json

"dependencies": {
    "ajv": "^5.1.5",
    "alt": "^0.17.8",
    "alt-container": "^1.0.2",
    "autoprefixer": "^6.4.0",
    "axios": "^0.7.0",
    "babel-cli": "^6.10.1",
    "babel-core": "^6.3.26",
    "babel-loader": "^7.1.2",
    "babel-plugin-syntax-decorators": "^6.3.13",
    "babel-polyfill": "^6.3.14",
    "babel-preset-es2015": "^6.3.13",
    "babel-preset-react": "^6.3.13",
    "babel-preset-stage-0": "^6.3.13",
    "babel-types": "^6.4.5",
    "body-parser": "^1.14.1",
    "chai": "^3.4.1",
    "chai-enzyme": "^0.6.1",
    "css-loader": "^0.23.1",
    "enzyme": "^2.5.0",
    "es5-shim": "^4.1.14",
    "es6-promise": "^3.0.2",
    "expose-loader": "^0.7.1",
    "fbjs": "^0.8.16",
    "file-loader": "^1.1.5",
    "fixed-data-table-2": "^0.7.11",
    "immutable": "^3.7.5",
    "imports-loader": "^0.6.5",
    "jade": "^1.11.0",
    "jquery": "^2.1.4",
    "jquery-ujs": "^1.1.0-1",
    "jsdom": "^7.0.2",
    "loader-utils": "^0.2.11",
    "lodash": "^4.11.1",
    "lodash-uuid": "^0.0.3",
    "mocha-jsdom": "^1.0.0",
    "moment": "^2.11.1",
    "postcss-loader": "^0.10.1",
    "react": "^15.6.1",
    "react-addons-test-utils": "15.4.0",
    "react-bootstrap": "^0.30.3",
    "react-dnd": "^2.5.4",
    "react-dnd-html5-backend": "^2.0.0",
    "react-dnd-test-backend": "^1.0.0",
    "react-dom": "^15.6.1",
    "react-fa": "^4.1.2",
    "react-height": "^3.0.0",
    "react-json-tree": "^0.10.9",
    "react-on-rails": "10.0.0",
    "react-onclickoutside": "^5.7.0",
    "react-overlays": "^0.6.2",
    "react-select": "^1.0.0-rc.3",
    "react-table": "^6.0.5",
    "react-textarea-autosize": "^4.0.5",
    "sass-loader": "^6.0.6",
    "sinon": "^1.17.2",
    "sinon-chai": "^2.8.0",
    "sleep": "^3.0.0",
    "source-map": "^0.6.1",
    "uglify-js": "^2.8.29",
    "url-loader": "^0.5.6",
    "webpack": "^3.1.0",
    "webpack-dev-server": "^2.9.2"
  },
  "devDependencies": {
    "babel-eslint": "^6.1.0",
    "babel-istanbul": "^0.11.0",
    "babel-plugin-react-transform": "^2.0.0",
    "bootstrap-loader": "^2.0.0",
    "bootstrap-sass": "^3.3.6",
    "eslint": "^3.3.0",
    "eslint-config-airbnb": "^10.0.1",
    "eslint-config-shakacode": "^0.0.1",
    "eslint-plugin-import": "^1.13.0",
    "eslint-plugin-jsx-a11y": "^2.1.0",
    "eslint-plugin-react": "^6.0.0",
    "esprima-fb": "^15001.1001.0-dev-harmony-fb",
    "express": "^4.13.3",
    "extract-text-webpack-plugin": "3.0.1",
    "image-webpack-loader": "^3.1.0",
    "mocha": "^2.3.3",
    "mocha-jenkins-reporter": "^0.1.9",
    "mocha-jsdom": "^1.0.0",
    "node-sass": "4.0.0",
    "react-loadable": "^5.3.0",
    "react-transform-hmr": "^1.0.1",
    "resolve-url-loader": "^1.4.3",
    "style-loader": "^0.19.0",
    "stylelint": "^7.1.0",
    "stylelint-config-standard": "^12.0.0"
}

File Structure

webpack.client.rails.config.js
app
    /assets
        /javascripts
            /generated
            -- app-bundle.js
            -- vendor-bundle.js
client
    /app
        /bundles
            /[APP ENTRY]...
    /node_modules
    webpack.client.rails.config.js
    webpack.client.base.config.js

webpack.client.rails.config.js

const webpack = require('webpack');
const path = require('path');
const config = require('./webpack.client.base.config');

const devBuild = process.env.NODE_ENV !== 'production';

const autoprefixer = require('autoprefixer');

config.output = {
  filename: '[name]-bundle.js',
  path: path.resolve('../app/assets/javascripts/generated'),
  publicPath: path.resolve('/assets/generated/'),
};

config.entry.vendor.unshift(
  'es5-shim/es5-shim',
  'es5-shim/es5-sham'
);

config.entry.vendor.push('jquery-ujs');

config.module.rules.push(
  {
    test: /\.jsx?$/,
    loader: 'babel-loader',
    exclude: /node_modules/,
  },
  {
    test: require.resolve('react'),
    loader: 'imports-loader?shim=es5-shim/es5-shim&sham=es5-shim/es5-sham',
  },
  {
    test: require.resolve('jquery-ujs'),
    loader: 'imports-loader?jQuery=jquery',
  },
  {
    test: /\.css$/,
    loader: 'style-loader!css-loader',
  },
  {
    test: /\.scss$/,
    use: [
      'style-loader',
      'css-loader',
      {
        loader: 'postcss-loader',
        options: {
          plugins: function() {
            return [autoprefixer]
          }
        }
      },
      'sass-loader',
    ],
    exclude: /assets\/stylesheets\/common\/packages\/DocumentEditor/,
  },
  {
    test: /\.scss$/,
    use: [
      'style-loader?{"singleton":true,"attrs":{"id":"document-content-stylesheet"}}',
      'css-loader',
      {
        loader: 'postcss-loader',
        options: {
          plugins: function() {
            return [autoprefixer]
          }
        }
      },
      'sass-loader',
    ],
    include: /assets\/stylesheets\/common\/packages\/DocumentEditor/,
  },
  {
    test: /\.(ttf|eot|svg)(\?v=[0-9]\.[0-9]\.[0-9])?$/,
    loader: 'file-loader',
  },
  {
    test: /\.woff(2)?(\?v=[0-9]\.[0-9]\.[0-9])?$/,
    loader: 'url-loader?limit=10000&mimetype=application/font-woff',
  }
);

module.exports = config;

if (devBuild) {
  console.log('Webpack dev build for Rails'); // eslint-disable-line no-console
  module.exports.devtool = 'eval-source-map';
} else {
  config.plugins.push(
    new webpack.optimize.DedupePlugin()
  );
  console.log('Webpack production build for Rails'); // eslint-disable-line no-console
}

webpack.client.base.config.js

const webpack = require('webpack');
const path = require('path');
const aliases = require('./aliases');

const devBuild = process.env.NODE_ENV !== 'production';
const nodeEnv = devBuild ? 'development' : 'production';

module.exports = {

  context: __dirname,
  entry: {

    vendor: [
      'babel-polyfill',
      'jquery',
    ],

    app: [
      './app/bundles/BundleOne/startup/clientRegistration',
      './app/bundles/BundleTwo/startup/clientRegistration',
      './app/bundles/BundleThree/startup/clientRegistration',
      './app/bundles/BundleFour/startup/clientRegistration',
      './app/bundles/BundleFive/startup/clientRegistration',
      './app/bundles/BundleSix/startup/clientRegistration',
      './app/bundles/BundleSeven/startup/clientRegistration',
    ],
  },
  resolve: {
    modules: [
      path.resolve('./app/bundles'),
    ],
    extensions: ['.js', '.jsx'],
    alias: aliases,
  },
  plugins: [
    new webpack.DefinePlugin({
      'process.env': {
        NODE_ENV: JSON.stringify(nodeEnv),
      },
    }),

    new webpack.optimize.CommonsChunkPlugin({
      name: 'vendor',
      filename: 'vendor-bundle.js',
      minChunks: Infinity,
    }),
  ],
  module: {
    rules: [
      { test: require.resolve('jquery'), loader: 'expose-loader?jQuery' },
      { test: require.resolve('jquery'), loader: 'expose-loader?$' },
    ],
  },
};

Solution

I think the problem is that when you set the following option in your webpack.client.base.config.js:

resolve: {
  modules: [
    path.resolve('./app/bundles'),
  ],
  extensions: ['.js', '.jsx'],
  alias: aliases,
},

You override the default resolve modules option which is

resolve: { modules: ['node_modules'] }.

If you want webpack to find modules in your bundles folder aswell as your node modules folder, you should try something like the following:

resolve: {
  modules: [
    path.resolve('./app/bundles'),
    'node_modules'
  ],
  extensions: ['.js', '.jsx'],
  alias: aliases,
},

EDIT: Also, you shouldn't look at webpack 1 docs if you're trying to upgrade to webpack 2. See the latest documentation instead.