react-native-kin

React Native wrapper for Kin ecosystem SDK for iOS and Android

---

Overall Kin doc: https://partners.kinecosystem.com/docs/server/jwt_service.html

Getting started

$ npm install react-native-kin --save

Mostly automatic installation - does not work for iOS

$ react-native link react-native-kin

Manual installation

iOS

1. Podfile should look like this:

# Uncomment the next line to define a global platform for your project
platform :ios, '9.0'

use_frameworks!
use_modular_headers!

workspace 'demo_pods.xcworkspace' # change to your name

def shared_pods
  pod 'KinEcosystem', '0.8.0' # always use latest version
  pod 'Alamofire'
end

target 'demo_pods' do
  # other pods...

  # RNKin:
  shared_pods

  target 'RNKin' do
    project '../node_modules/react-native-kin/ios/RNKin.xcodeproj'
    inherit! :search_paths
  end
end

2. pod install
3. In XCode, in the project navigator, select your project. Add libRNKin.a to your project's Build Phases ➜ Link Binary With Libraries
4. Run your project (Cmd+R)<

Android

1. Open up android/app/src/main/java/[...]/MainActivity.java
2. Add import com.kin.reactnative.RNKinPackage; to the imports at the top of the file
3. Add new RNKinPackage() to the list returned by the getPackages() method
4. Append the following lines to android/settings.gradle:

   include ':react-native-kin'
   project(':react-native-kin').projectDir = new File(rootProject.projectDir, 	'../node_modules/react-native-kin/android')
   

5. Insert the following lines inside the dependencies block in android/app/build.gradle:

     compile project(':react-native-kin')
   

Additional Installation/Setup:

iOS:

• if your iOS project is ObjC only, then add an empty swift file DummyToAvoidBuildProblem.swift to avoid building issues. And also add the bridge header. More infos: https://stackoverflow.com/a/50495316/2842800

Android:

• MainApplication.java: change to new RNKinPackage(MainApplication.this)
• add repository maven { url 'https://jitpack.io' } to your project gradle: (TODO: use repo from subproject)

allprojects {
    repositories {
        ...
        maven { url 'https://jitpack.io' }
        ...
    }
}

Usage

import kin from 'react-native-kin';

Android Only: Set ENVIRONMENT

Add to AndroidManifest.xml:

<meta-data android:name="com.kin.ecosystem.sdk.EnvironmentName" android:value="${kinEnvironmentName}" />

Add to app/build.gradle:

buildTypes { 
    debug {
        ...
        manifestPlaceholders = [kinEnvironmentName:"@string/kinecosystem_environment_beta"]
    }
    release {
        ...
        manifestPlaceholders = [kinEnvironmentName:"@string/kinecosystem_environment_production"]
    }
}

Set credentials & Start Kin SDK

As soon as you have a unique id from your user, start the Kin SDK

kin.setCredentials({
    "apiKey": "ABCD", // get from Kin
    "appId": "abcd", // get from Kin
    "jwtServiceUrl": "https://localhost...", // see "Setup JWT Service"
    "jwtServiceHeaderAuth": "xyz.." // will be sent as "authorization" header
  })
  .then((credentials) => {
    // successfully set credentials
    // now you can start listening on events:
    initEventHandler();
  })
  // Start Kin SDK
  .then(() => kin.start({
    userId: userId, // must be a unique id
    username: username, // used in 'payToUser()' as description who sent Kin
    environment: kin.ENVIRONMENT_BETA, // or kin.ENVIRONMENT_PRODUCTION // only needed for iOS
    darkMode: false, // default: false => light mode
  }))
  .then((start) => {
    // successfully SDK started
    console.log('start', start);
  })
  .catch((error) => {
    // error :(
    console.error('start', error);
  });

// Listeners
initEventHandler() {
  kin.events.addListener('onNativeOfferClicked', (offer) => {
    console.log('Listener: offer clicked', offer);
  });
  kin.events.addListener('onBalanceChanged', (balance) => {
    console.log('Listener: amount changed', balance);
  });
}

// Important: Remove listeners if you dont need them anymore

Logout user

kin.logout()
  .then((success) => {
    console.log({ success });
  })
  .catch((error) => {
    console.error('logout', error);
  });

Launch marketplace

kin.launchMarketplace()
  .then((marketPlace) => {
    console.log({ marketPlace });
  })
  .catch((error) => {
    console.error('launchMarketplace', error);
  });

Launch marketplace history

kin.launchMarketplaceHistory()
  .then((marketPlaceHistory) => {
    console.log({ marketPlaceHistory });
  })
  .catch((error) => {
    console.error('launchMarketplaceHistory', error);
  });

Get wallet address

kin.getWalletAddress()
  .then((walletAddress) => {
    console.log({ walletAddress });
  })
  .catch((error) => {
    console.error('getWalletAddress', error);
  });

Get balance

kin.getCurrentBalance()
  .then((currentBalance) => {
    console.log({ currentBalance });
  })
  .catch((error) => {
    console.error('getCurrentBalance', error);
  });

Earn

Before you can use this function, the user has to launch the marketplace and click on "get started" to initialize everything.

kin.earn({
    offerId: 'unique-id',
    offerAmount: 100,
    offerTitle: 'This is a demo earn',
    offerDescription: 'earn: demo',
    recipientUserId: userId,
  })
  .then((jwtConfirmation) => {
    console.log(`https://jwt.io/#debugger-io?token=${jwtConfirmation}`);
  })
  .catch((error) => {
    console.error('earn', error);
  });

Spend

Before you can use this function, the user has to launch the marketplace and click on "get started" to initialize everything.

kin.spend({
    offerId: 'unique-id',
    offerAmount: 10,
    offerTitle: 'This is a demo spend',
    offerDescription: 'spend: demo',
    recipientUserId: userId, // current user id
  })
  .then((jwtConfirmation) => {
    console.log(`https://jwt.io/#debugger-io?token=${jwtConfirmation}`);
  })
  .catch((error) => {
    console.error('spend', error);
  });

Pay to other user

Before you use this function, make sure the other user has an account

kin.hasAccount({
    userId: userId,
  })
  .then((hasAccount) => {
    alert(`hasAccount: ${hasAccount}`);
  })
  .catch((error) => {
    console.error('hasAccount', error);
  });

kin.payToUser({
    offerId: `pay-to-user-${userId}-${toUserId}`,
    offerAmount: 10,
    toUserId: toUserId,
    toUsername: toUsername,
    fromUsername: 'tester' // customize name here, or it will use the 'username' from start()
  })
  .then((jwtConfirmation) => {
    console.log(`https://jwt.io/#debugger-io?token=${jwtConfirmation}`);
    alert(`payToUser: ${jwtConfirmation}`);
  })
  .catch((error) => {
    console.error('payToUser', error);
  });

Add spend offer to marketplace

Use this before you launch the marketplace.

kin.addSpendOffer({
    offerId: offerId,
    offerAmount: 10,
    offerTitle: 'offer title',
    offerDescription: 'offer description',
    offerImageURL: 'https://via.placeholder.com/300x225',
    isModal: true, // close on tap = true; should always be true
  })
  .then((success) => {
    console.log(`addSpendOffer: ${offerId}: ${success}`);
  })
  .catch((error) => {
    console.error('addSpendOffer', error);
  });

Add earn offer to marketplace

Use this before you launch the marketplace.

kin.addEarnOffer({
    offerId: offerId,
    offerAmount: 10,
    offerTitle: 'offer title',
    offerDescription: 'offer description',
    offerImageURL: 'https://via.placeholder.com/300x225',
    isModal: true, // close on tap = true; should always be true
  })
  .then((success) => {
    console.log(`addSpendOffer: ${offerId}: ${success}`);
  })
  .catch((error) => {
    console.error('addSpendOffer', error);
  });

Remove earn/spend offer from marketplace

Use this before you launch the marketplace.

kin.removeOffer({
    offerId: offerId,
  })
  .then((success) => {
    console.log(`removeOffer: ${offerId}: ${success}`);
  })
  .catch((error) => {
    console.error('removeOffer', error);
  });

Setup JWT Service

1. clone: https://github.com/kinecosystem/jwt-service
2. create .sh file create_keys.sh + chmod +x create_keys.sh

#!/bin/sh
# usage:   program <DIR>
# example: program /tmp/out

if [ $# -ge 1 ]
then
    DIR=$1
else
    DIR=.
fi

for i in `seq 1 10`; do
    uuid=$(uuidgen)

    pub=es256_$uuid.pem
    priv=es256_$uuid-priv.pem

    openssl ecparam -name secp256k1 -genkey -noout -out $DIR/keys/$priv
    openssl ec -in $DIR/keys/$priv -pubout -out $DIR/keys/$pub

done

3. and create keys ./create_keys.sh
4. send public keys to kin team (tell them kid = es256_UUID)
5. npm run transpile
6. npm start

Add security layer with "authorization" header.

Native Module Reads

• https://facebook.github.io/react-native/docs/native-modules-ios.html
• https://facebook.github.io/react-native/docs/native-modules-android
• https://teabreak.e-spres-oh.com/swift-in-react-native-the-ultimate-guide-part-1-modules-9bb8d054db03#d267

Demo - Start the example app

see example/demo_pods/README.md