I want to calculate an average gas fee paid for all transactions on the RSK within the last three months. I tried to query the RSK blockchain using the Web3.js library. To get transaction data for just a single block height, I had to do:
const txsPerBlock = await web3.getBlockTransactionCount(block.height);
const txs = await Promise.all(
[...Array(txsPerBlock).keys()].map(
(i) => web3.eth.getTransactionFromBlock(block.height, i))
);
And then to calculate the average gas fee:
const averageGasFee = txs.reduce(
(p, c) => p + Number(c.gasPrice) * c.gas,
0
) / txs.length;
However, within 3 months there were about 230,000 blocks on RSK including about 3 transactions per block. So I had to poll about 600,000 transactions that would take forever to complete. I waited for an hour and then canceled the script. Is there a better to query the RSK blockchain and calculate the average transaction gas fee over such a large number of blocks and transactions?
You can use the getBlock() method (docs) that is able to return all transactions in the block at once if you pass true as the second param (returnTransactionObjects).
const block = await web3.eth.getBlock(blockNumber, true);
const averageGasFee = block.transactions.reduce(
(p, c) => p + Number(c.gasPrice) * c.gas,
0
) / block.transactions.length;
This results in "only" 230k requests instead the previous 600k.
It's much easier to accomplish this using Covalent. You can calculate the desired gas fees by performing a single PostgreSQL query:
SELECT AVG(t.gas_spent * t.gas_price) / 10^18 AS gas_paid
FROM chain_rsk_mainnet.block_transactions t
WHERE
t.signed_at > (NOW() - INTERVAL '3 month')
AND t.signed_at <= NOW()
;
The result of this query is 0.000009922904625 (RBTC),
and it took only 4.2 seconds to execute/ obtain the result.