How to know block where contact deployed in smart contact?

[vietnguyen09]

Hi guys,

I want to build a price chart, and my approach to this is using getReserves({ blockTag: "earliest" }) to fetch a token price in each block.
But the problem is I don't know where is the block from which the contact is deployed when I use getReserves with blockTag override.

I also come up with filter too but it still fails if I start with the earliest block.

const filter = tokenContract0.filters.Transfer()
filter.fromBlock = "earliest";
filter.toBlock = "latest";
provider.getLogs(filter).then((logs) => {
  //
});

Any idea?

[ricmoo]

Tha "earliest" block tag is just an alias for 0. Most backends will fail if the range is too large or if the number of results is too many.

You can try using services like Etherscan to narrow your search, but this isn’t something built-in to the Ethereum RPC. :(

[vietnguyen09]

Thank you for your answer, ok. I'm using Bscscan now. But there is one more problem, getReserves too slow if I put it in a loop to get token's price on each block :(, I'm trying to use parseLog but it still missing too much information to calculate the token's price :(.

const params = {
	module: 'logs',
	action: 'getLogs',
	fromBlock: 0,
	toBlock: latestBlock,
	address: tokenAddress,
	topic2: '0x000000000000000000000000b6696ee42ca9f216296ea9c8a5aa388e94fd7132',
	apiKey: 'API_KEY'
};
const api = `https://api.bscscan.com/api?${new URLSearchParams(params).toString()}`
const json = await fetch(api).then((result) => result.json());

const iface = new ethers.utils.Interface(pancakePair);
json.result.map((trans) => {
	trans.decode = iface.parseLog({ data: trans.data, topics: trans.topics });
})

Can you point me to something else to calculate the token's price for each transaction?

Thanks a lot.