Kaleido sample code for Corda

Sample code for development components of a Corda App: contracts, flows and rpc-clients, based on JDK 8

© Copyright 2020 Kaleido

Pre-reqs

• JDK 8 (such as from https://adoptopenjdk.net/
• gradle (https://gradle.org/install/)

Set up the target Corda network

Go to kaleido.io, sign up and create a Corda blockchain environment with at least two user Corda nodes (the platform with create a 3rd node as the notary for you, as a fully managed setup).

Define users and role for each node you want to send transactions to.

Set up the Kaleido bridge and running it locally on your laptop, so that your RPC client program can communicate with your Corda node running in Kaleido.

Go to the next step to build the IoU contract and flow jars.

Build

The 3 components can be built together or separately.

To build everything:

./gradlew buildAll

The output are in these folders:

• iou-contract/build/libs/iou-contract-1.0.jar
• iou-flow/build/libs/iou-flow-1.0.jar
• rpc-client/build/install/bin/rpc-client

To build each component separately:

./gradlew :iou-contract:build
./gradlew :iou-flow:build
./gradlew :rpc-client:build
./gradlew :rpc-client:installDist

Deploy

Kaleido CorDapp management will automatically sign the contract and flow jars when you use the platform to deploy them to your Corda environment in Kaleido. If you are using this sample against a locally set up Corda network, you must sign the jars yourself in order to deploy them.

Deploying to Corda networks in Kaleido

Using the Kaleido Console UI or APIs, you can easily upload the unsigned jars into Kaleido's contract management and promote them to your Corda environment. Then you can decide when to accept them into your Corda nodes, and will be prompted to restart the Corda server to pick up the new jars. Kaleido will make sure the jars get properly signed.

Deploying to a local Corda network

You will need to sign the jars yourself with the node identity key. Below is a sample command to sign:

jarsigner -keystore /corda/certificates/nodekeystore.jks -storepass $PASS ./iou-contract/build/libs/iou-contract.jar identity-private-key

Run

The program supports the following commands and switches:

Command	Parameter	Usage
issue		Issue a new IoU
	-u, --url	URL of the target Corda node or the local Kaleido bridge endpoint
	-n, --username	username for authentiation
	-p, --password	password for authentiation
	-b, --borrower-id	Name of the borrower to issue the IoU to, can be a partial search string
	-v, --value	Value of the issued IoU contract
	-w, --workers	Number of concurrent workers, default 1
	-l, --loops	Loops each worker executes before exiting, default 1 (0=infinite)
query		Query a past IoU issuance transaction
	-u, --url	URL of the target Corda node or the local Kaleido bridge endpoint
	-n, --username	username for authentiation
	-p, --password	password for authentiation
	-i, --tx-id	Transaction id of an existing transaction

Test Issuance of an IOU

To create a new IoU from the lender and have the borrower sign it and for the notary to notarize it:

$ rpc-client/build/install/rpc-client/bin/rpc-client issue -u localhost:10011 -n user1 -p test

The client will discover all the participants in the network and prompt you for a node as the counterprise (borrower), make sure to pick the other node you created in the network, not the node you are connected to or the notary.

Query Past Transactions

To query a completed transaction, copy the transaction ID from the output above and use it as the value of -i:

$ rpc-client/build/install/rpc-client/bin/rpc-client query -u localhost:10011 -n user1 -p test -i 311E4723F5B1C647BCD3472BC6097E708487331100A36ACAC821C22D7DC46D22

[main] INFO net.corda.client.rpc.internal.RPCClient - Startup took 1197 msec
[main] INFO io.kaleido.ClientRpcExample - Calling node for current time...
[main] INFO io.kaleido.ClientRpcExample - 2020-04-06T15:48:07.444985Z
[main] INFO io.kaleido.ClientRpcExample - Calling node for node info...
[main] INFO io.kaleido.ClientRpcExample - NodeInfo(addresses=[zzmrepgprk.zzdrbkw7k1.kaleido.network:10000], legalIdentitiesAndCerts=[CN=Node of zzmrepgprk for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US], platformVersion=6, serial=1586061213623)
[main] INFO io.kaleido.ClientRpcExample - Calling node for notary information...
[main] INFO io.kaleido.ClientRpcExample - [CN=Node of zzmreppmqy for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US]
[main] INFO io.kaleido.ClientRpcExample - Number of IOU states returned from query: 3
[main] INFO io.kaleido.ClientRpcExample - Found state by transaction hash:
[main] INFO io.kaleido.ClientRpcExample -   Notary: CN=Node of zzmreppmqy for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US
[main] INFO io.kaleido.ClientRpcExample -   Value: 100
[main] INFO io.kaleido.ClientRpcExample -   IoU lender: CN=Node of zzmrepgprk for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US
[main] INFO io.kaleido.ClientRpcExample -   IoU borrower: CN=Node of zzabcdefgh for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US

Reference

Here's a print out of the saved State objects inside a Corda node's state database (called "Vault"):

Page(
  states=[
    StateAndRef(
      state=TransactionState(
        data=IOUState(
          value=100,
          lender=CN=Node of zzmrepgprk for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US,
          borrower=CN=Node of zzabcdefgh for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US,
          linearId=093ac716-8594-4650-a893-419d6e6893b2
        ),
        contract=io.kaleido.contract.IOUContract,
        notary=CN=Node of zzmreppmqy for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US,
        encumbrance=null,
        constraint=SignatureAttachmentConstraint(
          key=(Public key: DLCTymWiNxvGWE117QUKSjeW71yaaGc5tNL2i8Zp8dFUvE, weight: 1, Public key: DLEoyzE6Y6Jyw5rRP2yqzGdJpBGCqGsZWD19u6BJdVgVr4, weight: 1)
        )
      ),
      ref=DA263D8AB3225C0F4BC81FB7512F3D9A416BFAC89832CCB8D054AEE0CC91BF59(0)
    ),
    StateAndRef(
      state=TransactionState(
        data=IOUState(
          value=100,
          lender=CN=Node of zzmrepgprk for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US,
          borrower=CN=Node of zzabcdefgh for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US,
          linearId=aa6a3f4d-a5eb-45de-9412-3df76b634638
        ),
        contract=io.kaleido.contract.IOUContract,
        notary=CN=Node of zzmreppmqy for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US,
        encumbrance=null,
        constraint=SignatureAttachmentConstraint(
          key=(Public key: DLCTymWiNxvGWE117QUKSjeW71yaaGc5tNL2i8Zp8dFUvE, weight: 1, Public key: DLEoyzE6Y6Jyw5rRP2yqzGdJpBGCqGsZWD19u6BJdVgVr4, weight: 1)
        )
      ),
      ref=311E4723F5B1C647BCD3472BC6097E708487331100A36ACAC821C22D7DC46D22(0)
    )
  ],
  statesMetadata=[
    StateMetadata(
      ref=DA263D8AB3225C0F4BC81FB7512F3D9A416BFAC89832CCB8D054AEE0CC91BF59(0),
      contractStateClassName=io.kaleido.state.IOUState,
      recordedTime=2020-04-05T15:41:35.881766Z,
      consumedTime=null,
      status=UNCONSUMED,
      notary=CN=Node of zzmreppmqy for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US,
      lockId=null,
      lockUpdateTime=null,
      relevancyStatus=RELEVANT,
      constraintInfo=ConstraintInfo(
        constraint=SignatureAttachmentConstraint(
          key=(Public key: DLCTymWiNxvGWE117QUKSjeW71yaaGc5tNL2i8Zp8dFUvE, weight: 1, Public key: DLEoyzE6Y6Jyw5rRP2yqzGdJpBGCqGsZWD19u6BJdVgVr4, weight: 1)
        )
      )
    ),
    StateMetadata(
      ref=311E4723F5B1C647BCD3472BC6097E708487331100A36ACAC821C22D7DC46D22(0),
      contractStateClassName=io.kaleido.state.IOUState,
      recordedTime=2020-04-06T14:21:51.889793Z,
      consumedTime=null,
      status=UNCONSUMED,
      notary=CN=Node of zzmreppmqy for zzdrbkw7k1, O=Kaleido, L=Raleigh, C=US,
      lockId=null,
      lockUpdateTime=null,
      relevancyStatus=RELEVANT,
      constraintInfo=ConstraintInfo(
        constraint=SignatureAttachmentConstraint(
          key=(Public key: DLCTymWiNxvGWE117QUKSjeW71yaaGc5tNL2i8Zp8dFUvE, weight: 1, Public key: DLEoyzE6Y6Jyw5rRP2yqzGdJpBGCqGsZWD19u6BJdVgVr4, weight: 1)
        )
      )
    )
  ],
  totalStatesAvailable=-1,
  stateTypes=UNCONSUMED,
  otherResults=[]
)