HealthCoinsApplication

Sample Corda Application on Token SDK based on Health coin use case .

CorDapp Nodes:

• Admin: This party issues fungible tokens to the employee when employee logs thier activity.
• Employee: This party initially log thier health activity like running ,cycling along with calories burned on that activity .Once employee log their activity they recieve fungible tokens that they redeem with partner merchants(HealthCoin) from the Admin.
• Merchant:This party recieve's token in exchange of an equivalant off ledger thing ,the merchant can then redeem these tokens on their side.
• Notary: notary node to check double-spend of input states then verify and sign final transaction.

This CorDapp example business-logic flows as below:

• 1. The Employee party logs the Activity state of type HealthCoinActivityState on ledger.
• 2. There would be Corda Service running in the background on the Admin Node which would listen to HealthCoinActivityState created by Employee and for every HealthCoinActivityState it would issue FungibleToken with Token Name as HealthCoin.
• 3. The Employee party can then review and view the HealthCoins issued by Admin and redeem those by transfering those to the Merchant party.
• 4. The Merchant party - offline review and validate the HealthCoins data received along with FungibleToken state. If everything is good, he can initiate the RedeemHealthCoinFlow flow to redeem the tokens .

Running the Health Coin Application.

First clone the source code from the git repository.

git clone https://github.com/amitpitambare/HealthCoinApplication.git
cd HealthCoinApplication

Once you have cloned the repository, you should open it with Eclipse/STS/IntelliJ. You can deployNodes to create four nodes (Admin.Employee,Merchant and Notary):

./gradlew clean deployNodes
./build/nodes/runnodes

Interacting with the CorDapp via Corda Shell

Use relevant node's Shell console to initiate the flows.

Let's start flows from each Corda node's shell console step-by-step:

1. To create HealthCoinActivityState - run below command on Employee node's console:

flow start HealthActivityLoggerFlow completedBy: Employee ,activityName: "Running" , caloriesBurned: 2000

To see state created run below command:

run vaultQuery contractStateType: com.healthcoin.state.HealthCoinActivityState

Now we have on ledger Health Activity of type HealthCoinActivityState.

2. Service running on background will initiate HealthCoinIssuanceFlow which will create Tokens with token name as "HealthCoin" and quantity based on the Calories burned in the health activity and it will create FungibleToken of type .

To see FungibleToken state created run below command again:

run vaultQuery contractStateType: com.r3.corda.lib.tokens.contracts.states.FungibleToken

You can see the FungibleToken data and copy the tokenName field value of it and save it with you as we required it in next step. If the Employee wants to redeem this token it can do it by transfering this to the merchant.

3. The Employee party can transfer any quantity of tokens that the 'Employee' is holder of.
Running below command on party Employee node's console:

flow start HealthCoinTransferFlow tokenName: "HealthCoin" ,holderName: "Employee" , quantity: 20 ,recipient: Merchant"

This flow will transfer the FungibleToken to Merchant.

4. The Merchant party can redeem the Tokens he holds:

flow start RedeemHealthCoinFlow tokenName: "HealthCoin" ,issuerName: Admin , quantity: 20 "

If we check and query the states we can find that the tokens are consumed and not available now.

run vaultQuery contractStateType: com.r3.corda.lib.tokens.contracts.states.FungibleToken

Future Scope

• Make use of Corda Accounts in Employee Node so that every employee's data is logically segregated in ledger.
• Create a Custom Token type so that we can custom token properties.