Installation

CorDapp

Let's run through how to install the solution. If you experience any issues here contact me at eric.mcevoy@r3.com

Gradle

Add to your Cordapp’s Gradle dependencies:

dependencies{
    // CorDapp dependency
    cordaCompile "com.cgraph:cgraph-core:1.0.0"
} 

Alternatively, you might want to fetch CGraph as a Cordapp fat JAR, in which case use compile instead of cordaCompile and skip the step below.

Add CGraph as Cordapps to your deployNodes task:

cordapp("com.cgraph:cgraph-core:1.0.0")

Config

You need to tell CGraph in CorDapp config where the node's corresponding GraphQL server lies. For development, you can configure this in both DriverDSL testing and in Cordformation.

Cordformation

node {
        name "O=Lender,L=London,C=GB"
        cordapp(project(':cgraph-core')) {
            config '''
                graphQLUrl="<INSERT_GRAPHQL_SERVER_URL>"
                graphQLToken="<INSERT_GRAPHQL_SERVER_X_AUTH_TOKEN>"
                graphBraidServerPort=8080
             '''
        }
        cordapp(project("cgraph-example")) {
            config '''
                braidServerPort=9090
             '''
        }
       ...
    }

or DriverDSL

startNode(
    parameters = NodeParameters(
        providedName = DUMMY_LENDER_NAME,
        rpcUsers = listOf(user),
        additionalCordapps = setOf(
            CGraph.Cordapps.Example.withConfig(
                mapOf(
                    "braidServerPort" to 9090
                )
            ),
            CGraph.Cordapps.Core.withConfig(
                mapOf(
                    "graphQLUrl" to DGRAPH_URL_LENDER,
                    "graphQLToken" to DGRAPH_TOKEN_LENDER,
                    "graphBraidServerPort" to 8080
                )
            )
        )
    )
)

Set up your graph

You need to specify the GraphQL server that CGraph will connect to. I chose DGraph as a first integration since the GraphQL server and KV store are in one process. However any GraphQL server should work. For each node you can either set up DGraph locally or remote.

Remote

DGraph has a free, one click deployable, instance that's super easy to get set-up over at DGraph Cloud. I use two premium (lender, borrower) instances for the demo and test. I'll add a version that works with a single instance for developer convenience in the future.

Locally

Golang set up golang and fetch binaries at DGraph Downloads

$GOPATH/bin/dgraph zero
$GOPATH/bin/dgraph alpha --port_offset 1 //notary clash

Docker

docker run --rm -it -p "8080:8080" -p "9080:9080" -p "8000:8000" -v ~/dgraph:/dgraph "dgraph/standalone:v21.03.0"

Edit the URL and Auth Token in deployCGraph gradle task in root build.gradle You can also edit the testing config in CGraphIOUDriverTesting to run the sample DriverDSL test. This is the URL Corda will write to and, the URL clients will read from.

Running CGraph

Hit a terminal in the project root directory:

./gradlew clean deployCGraph TODO
./build/nodes/runnodes

This brings up 3 nodes (Lender, Borrower and a Notary)

You then need to connect each Nodejs client to its corresponding node

cd cgraph/cgraph-js/
node.js cgraph-example-client.js 3000 8080
// new terminal tab
node.js cgraph-example-client.js 3001 8081

• You can interact with this HTTP API by using the Insomnia HTTP client json script CGraphInsomnia.json in the resources/scripts folder.
• The order in which you seed the data should go like this: Will provide mutations.
  • Member both goes directly into their own and each other's graph.
  • Currency written to ledger and then graph via lib. Hit node.js server over http.
  • Balance written to ledger. References currency and holder member, from above
  • IOU written to ledger. References all of above. IOU in both ledgers and graphs.

In future versions, there could be a more modular architecture for extending and integrating with more graph technologies, for example:

cgraph-cordapp 
cgraph-client
cgraph-schema-generator 
cgraph-testing
cgraph-sample-client
cgraph-sample-cordapp