Add newPendingTransactions and syncing To RSKj Eth_subscribe RPC Method

[elmol]

Add NewPendingTransactions To RSKj Eth_subscribe RPC Method

According to   rsk-gitcoin-hackathon-2021 - Add NewPendingTransactions To RSKj Eth_subscribe RPC Method , I worked on newPendingTransactions subscription event

Code Coverage

Attached coverage.zip you can find all the code coverage reports.

You can find the main change in coverage/ns-33/sources/source-e.html in the attached coverage reports.

Demonstration

Here you can see a demonstration about a new pending transactions notification.

new transaction created

rskj-node initialization

The following code was used for the demo.

const urlRSK = "ws://localhost:4445/websocket";

// Using web3js
const web3 = new Web3(urlRSK);

web3.eth.getBlockNumber().then((result) => {
  console.log("Latest Ethereum Block is ", result);
});

console.log("newPendingTxs...");

var subscription = web3.eth
  .subscribe("pendingTransactions", function (error, result) {
    if (!error) {
      console.log(result);
    } 
});

setTimeout(() => {
  console.log("unsubscribe");
  // unsubscribes the subscription
  subscription.unsubscribe(function (error, success) {
    if (success) console.log("Successfully unsubscribed!");
  });
}, 60000);


setTimeout(() => {
  console.log("GoodBye!");
  process.exit();
}, 61000); 

[elmol]

Add Syncing To RSKj Eth_subscribe RPC Method

This pull request was updated with the rsksmart/rsk-gitcoin-hackathon-2021#16 implementation .

[Vovchyk]

pipeline: run

[Vovchyk]

pipeline: run

[Vovchyk]

pipeline: run

[Vovchyk]

@elmol thanks for your submission. Good work. There are a few comments. Please check.

[Vovchyk]

according to the docs, result could either be false or an object with sync statistics. Could you please return false, if syncing is not active? Please refer to the examples of responses below:

< {"jsonrpc":"2.0","method":"eth_subscription","params":{"subscription":"0x8a70b5d09d8284c507b1cd1340330f73","result":false}}

< {"jsonrpc":"2.0","method":"eth_subscription","params":{"subscription":"0x8a70b5d09d8284c507b1cd1340330f73","result":{"syncing": true, "status": { "startingBlock": 0, "currentBlock": 0, "highestBlock": 24255}}}

pay attention that in the first example result is false, not {"syncing":false}

as reference, you can also check what the eth_syncing method does

[elmol]

Thanks Vovchyk, I've fixed.

[Vovchyk]

not sure this is a good place to emit start / stop events for the case of syncing. This SyncPool service is being started even if a node is already fully synced. I guess we should mimic the behaviour of the eth_syncing method

I believe a good candidate where this can be done is the SyncProcessor class. E.g. emitting start event in the startDownloadingBodies and stop - in stopSyncing. What do you think?

[elmol]

Yes, totally agreed! I've moved from the events from SyncPool to SyncProcessor.

[Vovchyk]

pipeline: run

[Vovchyk]

pipeline: run

[Vovchyk]

thanks @elmol for your corrections. Just posted a few minor comments. In general, LGTM

[elmol]

Thank you very much @Vovchyk for your comments and corrections.

[Vovchyk]

pipeline: run