Remove console.logs with Webpack & Uglify

With UglifyJsPlugin we can handle comments, warnings, console logs but it will not be a good idea to remove all these in development mode. First check whether you are running webpack for prod env or dev env, if it is prod env then you can remove all these, like this:

var debug = process.env.NODE_ENV !== "production";plugins: !debug ? [   new webpack.optimize.UglifyJsPlugin({     // Eliminate comments        comments: false,    // Compression specific options       compress: {         // remove warnings            warnings: false,         // Drop console statements            drop_console: true       },    })]: []

Reference: https://github.com/mishoo/UglifyJS2#compressor-options

UPDATE 2019Need to use terser plugin now for ES6 support in webpack v4https://github.com/webpack-contrib/terser-webpack-plugin#terseroptions

webpack.config.js

module.exports = {  optimization: {    minimizer: [      new TerserPlugin({        sourceMap: true, // Must be set to true if using source-maps in production        terserOptions: {          compress: {            drop_console: true,          },        },      }),    ],  },};

Try drop_console:

plugins: [    new Webpack.optimize.UglifyJsPlugin({      compress: {        drop_console: true,      }    }]

Update: For webpack v4 it has changed a little:

const UglifyJSPlugin = require('uglifyjs-webpack-plugin');...optimization: {  minimizer: [    new UglifyJSPlugin({      uglifyOptions: {        compress: {          drop_console: true,        }      }    })  ]}

I personally think console logs (especially console.error) are very useful on prod and think it's a good idea to keep them. If you really want to drop specific console functions such as just console.log you should use pure_funcs option e.g. pure_funcs: ['console.log'] and this will drop console.log since pure functions do not produce side effects then Uglify can discard ones not assigned to anything.

optimization: {  minimizer: [    new UglifyJSPlugin({      uglifyOptions: {        compress: {          // Drop only console.logs but leave others          pure_funcs: ['console.log'],        },        mangle: {          // Note: I'm not certain this is needed.          reserved: ['console.log']        }      }    })  ]}

For TerserJS (Uglify is deprecated and does not support new JS features you should NOT use it)

optimization: {  minimizer: [    new TerserPlugin({      terserOptions: {        compress: {            drop_console: true        }      }    })  ]}

As discussed you can also use pure_funcs alternatively.

This is the new syntax for Webpack v4:

optimization: {  minimizer: [    new UglifyJSPlugin({      uglifyOptions: {        compress: {          drop_console: true        },        output: {          comments: false        }      },    }),  ],},