webpack template production and develop

webpack.config.js

const path = require('path');
const ExtractTextPlugin = require('extract-text-webpack-plugin');
const CleanWebpackPlugin = require('clean-webpack-plugin');


module.exports = (env) => {
  const plugins = [
    new ExtractTextPlugin("css/[name].[hash].css")
  ]

  if (env.NODE_ENV === 'production') {
    plugins.push(
      new CleanWebpackPlugin(['dist'], {root: __dirname})
    )
  }

  return {

    entry: {
      "santo": path.resolve(__dirname, 'src/index.js'),
    },
    output: {
      path: path.resolve(__dirname, 'dist'),
      filename: 'js/[name].[hash].js',
      publicPath: path.resolve(__dirname, 'dist')+"/",
      chunkFilename: 'js/[id].[chunkhash].js',
    },
    devServer: {
      port: 9000,
    },
    module: {
      rules: [
        {
          // test: que tipo de archivo quiero reconocer,
          // use: que loader se va a encargar del archivo
          test: /\.(js|jsx)$/,
          exclude: /(node_modules)/,
          use: {
            loader: 'babel-loader',
            options: {
              presets: ['es2015', 'react', 'stage-2'],
            }
          },
        },
        {
          test: /\.css$/,
          use: ExtractTextPlugin.extract({
            use: [
              {
                loader: 'css-loader',
                options: {
                  minimize: true,
                }
              }
            ]
          })
        },
        {
          test: /\.(jpg|png|gif|svg)$/,
          use: {
            loader: 'url-loader',
            options: {
              limit: 10000,
              fallback: 'file-loader',
              name: 'images/[name].[hash].[ext]',
            }
          }
        },
      ]
    },
    plugins
  }
}

webpack.dev.config.js

const path = require('path');

module.exports = {
  entry: {
    "santo": path.resolve(__dirname, 'src/index.js'),
  },
  output: {
    path: path.resolve(__dirname, 'dist'),
    filename: 'js/[name].js'
  },
  devServer: {
    port: 9000,
  },
  devtool:'eval-source-map',
  module: {
    rules: [
      {
        // test: que tipo de archivo quiero reconocer,
        // use: que loader se va a encargar del archivo
        test: /\.(js|jsx)$/,
        exclude: /(node_modules)/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: ['es2015', 'react', 'stage-2'],
          }
        },
      },
      {
        test: /\.css$/,
        use: ['style-loader', 'css-loader']
      },
      {
        test: /\.(jpg|png|gif|svg)$/,
        use: {
          loader: 'url-loader',
          options: {
            limit: 1000000,
            fallback: 'file-loader',
            name: 'images/[name].[hash].[ext]',
          }
        }
      },
    ]
  }
}