Unable to subscribe mempool via websocket

[anggapur]

Hello, I'm currently working on a project that create a webhook, and this webhook will be able to listen to pending transactions (mempool). But I'm unable to find any clue about subscribe mempool on polygon edge.

I try to subscribe polygon edge's mempool with ethers js, here my code

const WS_URL = '{My Polygon Websocket Here}';
const provider =  new ethers.providers.WebSocketProvider(WS_URL);

provider.on("pending", (tx) => {
    // Emitted when any new pending transaction is noticed
});

Note: this code works on public chain (tested on mumbai & goerli)

But it return errors when I try to subscribe to polygon edge, here the error that I got :

Error : subscribe method newPendingTransactions not found

After a short research, I found that it seems like polygon edge not yet support subscription for pending transactions ( newPendingTransactions method not supported yet )

polygon-edge/jsonrpc/dispatcher.go

Lines 165 to 175 in cac8de6

	if subscribeMethod == "newHeads" {
	filterID = d.filterManager.NewBlockFilter(conn)
	} else if subscribeMethod == "logs" {
	logQuery, err := decodeLogQueryFromInterface(params[1])
	if err != nil {
	return "", NewInternalError(err.Error())
	}
	filterID = d.filterManager.NewLogFilter(logQuery, conn)
	} else {
	return "", NewSubscriptionNotFoundError(subscribeMethod)
	}

is there any other way or trick to listen to polygon edge mempool?

[laviniat1996]

Hi @anggapur ,

We support Tx Pool subscription through gRPC. You can find a list of flags for subcription here, in the txpool subscribe flags category.

[anggapur]

Hi @laviniat1996 Thank you for the answer.
But it seems better if we had Tx pool subscription on Websocket like other node provider on public chain

[anggapur]

Hi @laviniat1996 Thank you for the answer.
But it seems better if we had Tx pool subscription on Websocket like other node provider on public chain

[rachit77]

Hi @anggapur,
I was curious, Why is a Tx pool subscription on WebSocket better than Http2(gRPC)?