找不到模块：在Heroku上部署时出错

Question

I have a react/ node app deployed on Heroku. When I try to deploy it, I am getting an error below.

ERROR in ./client/app.js
       Module not found: Error: Can't resolve './src/components/nav/navContainer' in '/tmp/build_1a01b67ad5e485946724b1ce1337f75b/client'

npm ERR! code ELIFECYCLE
npm ERR! errno 2
npm ERR! react-boilerplate@1.0.0 build:prod: `cross-env NODE_ENV=production webpack --config=webpack.prod.js`
npm ERR! Exit status 2
npm ERR! 
npm ERR! Failed at the react-boilerplate@1.0.0 build:prod script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR!     /tmp/npmcache.EDIfm/_logs/2019-09-01T06_09_08_862Z-debug.log
npm ERR! code ELIFECYCLE
npm ERR! errno 2
npm ERR! react-boilerplate@1.0.0 heroku-postbuild: `npm run build:prod`
npm ERR! Exit status 2
npm ERR! 
npm ERR! Failed at the react-boilerplate@1.0.0 heroku-postbuild script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR!     /tmp/npmcache.EDIfm/_logs/2019-09-01T06_09_08_877Z-debug.log

The path is correct. The app works fine in dev mode. I removed CaseSensitivePath plugin from webpack, in case if it causes an error. But it still fails with same error.

app.js

import NavContainer from './src/components/nav/navContainer';
...

export const App = ({ messageShow, children }) => (
  <div id="app absolute">
    <NavContainer />
    {messageShow !== null && (
      <div className="flex justify-center">
        <MessageBox />
      </div>
    )}
    {children}
  </div>
);

...

export default connect(
  mapPropsToState,
  null,
)(App);

const NavContainer = ({
...
}) => {
...

  return (
    <div className="nav relative">
...
    </div>
  );
};

...

export default withRouter(
  connect(
    mapStateToProps,
    mapDispatchToProps,
  )(NavContainer),
);

webpack.base.js

const webpack = require('webpack');
const path = require('path');
const CleanWebpackPlugin = require('clean-webpack-plugin');
const autoprefixer = require('autoprefixer');
const HTMLWebpackPlugin = require('html-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const { BundleAnalyzerPlugin } = require('webpack-bundle-analyzer');
const CopyWebpackPlugin = require('copy-webpack-plugin');

const NODE_ENV = process.env.NODE_ENV;
const devMode = NODE_ENV !== 'production';
const isTest = NODE_ENV === 'test';

const babelConfig = require('./.babelrc.js');

module.exports = {
  output: {
    filename: devMode ? 'bundle.js' : 'bundle.[hash].js',
    chunkFilename: devMode
      ? '[name].lazy-chunk.js'
      : '[name].lazy-chunk.[hash].js',
    path: path.resolve(__dirname, 'public/dist'),
    publicPath: '/',
  },
  resolve: {
    extensions: ['.js', '.jsx', '.json', '.scss', 'css'],
  },
  node: {
    fs: 'empty',
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /(node_modules|bower_components)/,
        use: [
          {
            loader: 'babel-loader',
            options: babelConfig,
          },
        ],
      },
      {
        test: /\.(sa|sc|c)ss$/,
        exclude: /node_modules/,
        use: [
          {
            loader: devMode ? 'style-loader' : MiniCssExtractPlugin.loader,
          },
          {
            loader: 'css-loader',
            options: {
              minimze: true,
              sourceMap: devMode,
              importLoaders: 1,
            },
          },
          {
            loader: 'postcss-loader',
            options: {
              indent: 'postcss',
              plugins: [
                autoprefixer({
                  browsers: ['last 1 versions', 'ie >= 11', '> 1%', 'not dead'],
                }),
              ],
              sourceMap: devMode,
            },
          },
          {
            loader: 'sass-loader',
            options: {
              sourceMap: devMode,
              includePaths: ['client/styles/main.scss'],
            },
          },
        ],
      },
      {
        test: /\.html$/,
        loader: 'html-loader',
        options: {
          attrs: ['img:src'],
        },
      },
      {
        test: /\.(jpe?g|png|gif|ico)$/,
        loader: 'file-loader',
        options: {
          name: devMode ? '[name].[ext]' : '[name].[hash].[ext]',
        },
      },
      {
        test: /\.svg$/,
        loader: 'file-loader',
        options: {
          name: devMode ? '[name].[ext]' : '[name].[hash].[ext]',
        },
      },
    ],
  },
  optimization: {
    runtimeChunk: 'single',
    splitChunks: {
      chunks: 'all',
      cacheGroups: {
        vendors: {
          test: /[\\/]node_modules[\\/]/,
          name: 'vendors',
          priority: -10,
        },
        default: {
          minChunks: 2,
          priority: -20,
          reuseExistingChunk: true,
        },
      },
    },
  },
  plugins: [
    new CleanWebpackPlugin(['public/dist']),
    new webpack.DefinePlugin({
      'process.env': {
        NODE_ENV: JSON.stringify(NODE_ENV),
      },
    }),
    new HTMLWebpackPlugin({
      template: './public/index.html',
      favicon: './static/favicons/favicon.ico',
    }),
    new MiniCssExtractPlugin({
      filename: devMode ? '[name].css' : '[name].[chunkhash].css',
      chunkFilename: devMode ? '[id].css' : '[id].[chunkhash].css',
    }),
    new CopyWebpackPlugin([
      { from: `${__dirname}/static`, to: `${__dirname}/public/dist` },
    ]),

    isTest
      ? new BundleAnalyzerPlugin({
          generateStatsFile: true,
        })
      : null,
  ].filter(Boolean),
};

webpack.prod.js

const merge = require('webpack-merge');
const OptimizeCssAssetsPlugin = require('optimize-css-assets-webpack-plugin');
const cssnano = require('cssnano');
const TerserPlugin = require('terser-webpack-plugin');
const BrotliPlugin = require('brotli-webpack-plugin');
const baseConfig = require('./webpack.base');

const config = {
  mode: 'production',
  entry: './client/index.js',
  devtool: 'source-map',
  optimization: {
    minimize: true,
    minimizer: [
      new OptimizeCssAssetsPlugin({
        assetNameRegExp: /\.optimize\.css$/g,
        cssProcessor: cssnano,
        cssProcessorOptions: {
          discardComments: { removeAll: true },
        },
        canPrint: true,
      }),
      new TerserPlugin({
        test: /\.js(\?.*)?$/i,
        exclude: /node_modules/,
        terserOptions: {
          ecma: 5,
          compress: true,
          output: {
            comments: false,
            beautify: false,
          },
        },
      }),
    ],
    runtimeChunk: {
      name: 'manifest',
    },
  },
  plugins: [new BrotliPlugin()],
};

module.exports = merge(baseConfig, config);
```

Answer 1

Please note that path directory configure in the cloud will be different from your local

So to solve this issue you have 2 ways:

• Build to prod mode before deploy everything to heroku

• Find a way to resolve path in the cloud so that webpack can run and build your code in cloud

Update: Delete a nav folder to fix an error.