Pigtail

A simple Braid service and JS client example.

Braid allows you to easily define a server running on your node that serves up flow and other endpoints that can be consumed in either Java or JavaScript.

We define our Braid server as follows:

@CordaService
class BootstrapBraidService(val serviceHub: AppServiceHub) : SingletonSerializeAsToken() {
    init {
        BraidConfig()
                // Include a flow on the Braid server.
                .withFlow(WhoAmIFlow::class.java)
                // Include a service on the Braid server.
                .withService("myService", BraidService(serviceHub))
                // The port the Braid server listens on.
                .withPort(8080)
                // Using http instead of https.
                .withHttpServerOptions(HttpServerOptions().setSsl(false))
                // Start the Braid server.
                .bootstrapBraid(serviceHub)
    }
}

After starting the node as normal, we consume its endpoints using a Node.js client.

Pre-requisites:

See https://docs.corda.net/getting-set-up.html.

Usage

Running the node:

See https://docs.corda.net/tutorial-cordapp.html#running-the-example-cordapp.

Running the client:

• Install npm and Node.js by following the instructions here: https://www.npmjs.com/get-npm
• Open a command-line terminal window
• Move into the client-js folder
• Install the dependencies using npm install
• Run the client using node client.js

Interacting with the node:

The client exposes three endpoints:

• localhost:3000/whoami-flow-callback, which uses Braid to call the WhoAmI flow on the node, and handles the response using callbacks
• localhost:3000/whoami-flow-promise, which uses Braid to call the WhoAmI flow on the node, and handles the response using promises
• localhost:3000/whoami-service, which uses Braid to call the BraidService on the node, and handles the response using callbacks