THIS ISSUE ONLY OCCURS ON ANDROID (SETTING UP IOS IS NOT MANDATORY)

Environment Setup

Follow the guide to setup your PC from React-Native Environment Setup

OR:

• Install node using brew brew install node but it's preferred to manage node using nvm nvm installation guide
• brew install watchman
• For mac system, install XCode

Required to run android

• Download Java Development Kit brew tap homebrew/cask-versions && brew install --cask zulu11
• Download and Install Android Studio
• Install Android SDK
  • To do that, open Android Studio, click on "More Actions" button and select "SDK Manager".
  • Select the "SDK Platforms" tab from within the SDK Manager, then check the box next to "Show Package Details" in the bottom right corner. Look for and expand the Android 12 (S) entry, then make sure the following items are checked:
    • Android SDK Platform 31
    • Intel x86 Atom_64 System Image or Google APIs Intel x86 Atom System Image or (for Apple M1 Silicon) Google APIs ARM 64 v8a System Image
• Create a new Virtual Device
  • Click More Actions on Android Studio
  • Select Virtual Device Manager
  • Select Any of the google arm packages and click next
  • Give the device a name or leave the default name and click Next
  • Select Portrait orientation and click finish
• Configure the ANDROID_HOME environment variable
  • Add the following lines to your ~/.zprofile or ~/.zshrc config file:
    • Open your terminal
    • run vim ~/.zshrc or vim ~/.zprofile
    • Press i on your keyboard and use your arrow keys to navigate to the last line of the editor
    • Add the following files to the last line of the opened editor

      export ANDROID_HOME=$HOME/Library/Android/sdk
      export PATH=$PATH:$ANDROID_HOME/emulator
      export PATH=$PATH:$ANDROID_HOME/platform-tools
  

  • Press Esc key key then type :wq to save and quit the editor
  • run source ~/.zshrc or source ~/.zprofile OR restart your terminal

To run the project

• Clone the project
• Run yarn && yarn run link && npx pod-install

To run on android:

• Run yarn run android

To run on iOS

• Run yarn run ios

Possible Error

• 144 duplicate symbols for architecture arm64 (This happens mostly on Apple Silicon chip machines)

Fix:

• Open ios directory and open BufferProject.xcworkspace
• Tap on the folder icon by the top left of XCode
• Select Pods from the left pane on XCode
• Under Targets, locate and select react-native-udp
  • Select Build Phases and expand Compile Sources
  • Delete GCDASyncUdpSocket.m from the list
• Under Targets again, locate and select TcpSockets
  • Select Build Phases and expand Compile Sources
  • Delete GCDASyncUdpSocket.m from the list
• Click the Play icon by the top left of Xcode

Problem

• Click the encrypt button on the initial screen
• Currently, the encrypt function uses the HashWasm.argon2id to encrypt

const hashOptions = {
        password: 'password',
        salt: salt,
        parallelism: 1,
        iterations: 256,
        memorySize: 2024,
        hashLength: 32, // we use output size = 32 bytes
        outputType: 'binary', // we use output binary
      };

      const result = await HashWasm.argon2id(hashOptions);

• This throws an error: [TypeError: undefined is not an object (evaluating 'buffer.toString')]
• NB: This happens only when debugger mode is disabled. If you're debugging with chrome, the function works fine without any errors

Adding more packages

• Stop the metro-bundler i.e. the terminal that opened after you started the application
• Install the package with yarn add package-name
• Run yarn run android
• For ios you might need to run npx pod-install again before running yarn run ios. You can check if you need the pod install from the npm page of the module you're adding. If not sure, always run npx pod-install first before yarn run ios

Files to note:

• App.js contains the function used for the encryption
• shim.js file is used to add to the global environment methods that are not supported by the mobile device. This includes (Buffer, BigInt, WebAssembly)

My Opinion

I feel the difference in node environment used by chrome-debug mode plays a role to this error.