const start = async () => {
    ...

    node.subscribe(channel.SYNC_BLOCK, async (buffer) => {
        const data = JSON.parse(buffer.data.toString())
        const currentNodeId = node.node.peerInfo.id.toB58String()
        if(data.nodeId == currentNodeId) {
            await bc.saveBlock(data.block)
            await bc.saveLatestHash(data.block.hash)
            await bc.clearSuccessTransactions(data.block.transactions)

            setTimeout(() => {
                node.publish(channel.SYNC_REQUEST, JSON.stringify({
                    nodeId: currentNodeId,
                    latestHash: data.block.hash,
                }))
            }, 2000)
        }
    })
}