metro-minify-obfuscator

A metro minifier based on javascript-obfuscator for React Native

Installation

yarn add -D metro-minify-obfuscator

or

npm i --save-dev metro-minify-obfuscator

Usage

• update metro.config.js on your project

module.exports = {
  transformer: {
    ...
    minifierPath: 'metro-minify-obfuscator', // <- add this
    minifierConfig: {
      defaultMinifierPath: require('metro-minify-uglify'), // required if filter/includeNodeModules options is set, can be metro-minify-uglify or metro-minify-terser dependes on RN version / available installed minifier
      filter: (filename) => true, // return true to obfuscate
      includeNodeModules: true, // set false to ignore node_modules from obfuscation
      trace: false, // show output log
      obfuscatorOptions: {
        // put additional javscript-obfuscator configuration here
      }
    },
  },
};

• you can add additional obfuscation config to the minifierConfig properties (⚠️ NOT ALL OPTION IS GUARANTEED WORKING ON REACT-NATIVE, IT MIGHT BREAK YOUR APPS 🙈 )
• run packager with --reset-cache argument to clear metro cache

Default Options

{
  "stringArray": false,
  "compact": true,
  "controlFlowFlattening": true,
  "controlFlowFlatteningThreshold": 0.75,
  "identifierNamesGenerator": "hexadecimal",
  "numbersToExpressions": true,
  "splitStrings": true,
  "splitStringsChunkLength": 3,
  "transformObjectKeys": true,
  "simplify": true,
  "disableConsoleOutput": true,
  "log": false,
  "selfDefending": true,
  "unicodeEscapeSequence": true
}

Comparison with other libraries

• metro-minify-obfuscator, obfuscate on minification step, can generate correct source maps
• obfuscator-io-metro-plugin, obfuscate on transformation, doesn't give 'working' source maps for now, if you don't care with source maps you can use use it
• react-native-obfuscating-transformer, obfuscate on transformation, if you combine it with --minify true it will shown that code looks doesn't obfuscated

Release History

• v1.0.x - Add additional option to filter / exclude node_modules file from obfuscation. ⚠️ upgrading to this version need update to your metro.config.js please be aware

// before
module.exports = {
  transformer: {
    ...
    minifierPath: 'metro-minify-obfuscator', // <- add this
    minifierConfig: {
      // put additional javscript-obfuscator configuration here
    },
  },
};

// after
module.exports = {
  transformer: {
    ...
    minifierPath: 'metro-minify-obfuscator', // <- add this
    minifierConfig: {
      defaultMinifierPath: require('metro-minify-uglify'), // required if filter/includeNodeModules options is set, can be metro-minify-uglify or metro-minify-terser dependes on RN version / available installed minifier
      filter: (filename) => true, // return true to obfuscate
      includeNodeModules: true, // set false to ignore node_modules from obfuscation
      trace: false, // show output log
      obfuscatorOptions: {
        // put additional javscript-obfuscator configuration here
      }
    },
  },
};

• v0.x.x - Initial fork from metro-minify-uglify configured with JSO library