Cardano Node JS

Components:

1.Interceptor

It intercepts connection between two cardano-nodes. The communication is logged with decoded protocol messages.

example:

##
## [[ Node1 ]] ----->>  [127.0.0.1:3001  [[Interceptor]]] ----->> [172.31.0.15:3002  [[Node 2]]]
##
yarn interceptor 0.0.0.0:3001 172.31.0.15:3002

2.Client

Attempts connection to remote node and

• maintain connection with it with periodic ping
• log all the communication to/from the server

example:

yarn client preview-node.world.dev.cardano.org:30002

3. Using As a Library

3.1 Following a node for latest transactions.

import { createInMemoryClientWithPeer } from "libcardano/helper"
import {parseRawBlockBody} from "libcardano/cardano/ledger-serialization/transaction";
import * as process from "process";

const blockchain = createInMemoryClientWithPeer(process.argv[2]|| "sanchonet-node.play.dev.cardano.org:3001",{
    networkMagic: parseInt(process.argv[3]) || 4,
    startPoint:'Latest'
})

blockchain.on("extendBlock", (block) => {
    const transactions = parseRawBlockBody(block.body)
    console.log("RollForward :", block.headerHash.toString('hex'), "blockNo:", block.blockNo, "slotNo:", block.slotNo,"txCount:",transactions.length)
})

blockchain.pipeline("rollback",([[slot,headerHash], blockNo],_currentTip, cb)=>{
    console.log("Rollback    :",headerHash.toString('hex'), "blockNo:",blockNo,"slotNo:",slot )
    setImmediate(cb)
})