Ability to lookup data on RChain

convolutedLookup.js

// When listening for data (or continuation) at a name, the returned
// blockResults contain only blocks in which data was actually sent on
// the specified name. HOWEVER, each block in the blockResults contains
// a postBlockData which contains ALL previous sends on the name, not
// only the sends in that block. This code demonstrates that behavior
// by sending on the public name @"testChan" in blocks 1, 3, and 5, but
// not in blocks 2, 4, and 6.
//
// Run this shit on a fresh node if you care about your sanity.
//
// This behaviour is clear enough now that I've figured it out, but it
// is not at all intuitive. Worse, it means that the data sent on @"testChan"
// is present in ALL future blocks (assuming it isn't consumed), but it
// cannot be queried unless the query depth extends back to at least
// the most recent send.

const { RNode } = require('rchain-api');
const grpc = require('grpc');

const myNode = RNode(grpc, {host: 'localhost', port: 40401});

function deployWithSend() {
  return {
    term: '@"testChan"!("data sent on testChan")',
    timestamp: (new Date()).valueOf(),
    phloLimit: { value: 999999 },
    phloPrice: { value: 1 },
  };
}

function deployWithoutSend() {
  return {
    term: '"Nothing to see here."',
    timestamp: (new Date()).valueOf(),
    phloLimit: { value: 999999 },
    phloPrice: { value: 1 },
  };
}

main();
async function main() {

  // Add blocks to DAG in pairs
  for (let x = 0; x < 3; x++) {
    console.log(await myNode.doDeploy(deployWithSend(), false));
    console.log(await myNode.createBlock());

    console.log(await myNode.doDeploy(deployWithoutSend(), false));
    console.log(await myNode.createBlock());
  }

  // Grab all blocks in which data was sent on @"testChan"
  // Change depth to observe trippy behavior
  const blockResults = await myNode.listenForDataAtPublicName('testChan', depth=1);
  console.log(`we got ${blockResults.length} blocks.`)
  // Uncomment for detailed logging of blocks
  //console.log(blockResults);

  // Investigate the most recent block with a send
  const data = blockResults[0].postBlockData;
  console.log(`We got ${data.length} sends in the latest block`);
  // Uncomment for detailed logging of sends in latest block
  //for (let datum of data) { console.log(datum.exprs); }
}