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Feed Registry

Feed Registry allows querying the prices on the chain from your smart contract using various endpoints. For a complete list of functions and parameters for the FeedRegistryInterface, see the Feed Registry API Reference.

Usages and Examples:

Querying all the existing feeds on-chain​

Binance FeedRegistry maintains a database of assets and their metadata on-chain. For your smart contract on the chain to fetch all the available feeds and their details, call:

getAllPairs()

You may also perform this query offchain. For instance using BSC Scan

Querying using Base and Quote addresses​

The FeedRegistry exposes a variant of AggregatorV3Interface for querying round data. Instead of using a pair specific smart contract, users may use token addresses to query the latest data from a single contract i.e. the FeedRegistry. To retrieve the latest data for ETH/USD from the registry using their token addresses, call:

latestRoundData(address base, address quote);

Ex: To query the latest ETH/USD price:

  • base: The ETH token address on BNB Chain ie "0x2170Ed0880ac9A755fd29B2688956BD959F933F8"
  • quote: The USD address representation "0x0000000000000000000000000000000000000348". This is based on ISO 4217
latestRoundData(0x2170Ed0880ac9A755fd29B2688956BD959F933F8, 0x0000000000000000000000000000000000000348)
caution

The USD token is not the same as stable coins such as BUSD, USDC etc. See guide for more details.

Querying using Token string names​

To make the process less error prone and to increase ease of use, FeedRegistry additionally allows users to query prices by using just the asset string names. In such a case, use

latestRoundDataByName(string memory base, string memory quote)

Code Examples​

Solidity​

PriceConsumer.sol
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "../interfaces/FeedRegistryInterface.sol";

contract PriceConsumer {
  FeedRegistryInterface internal s_feedRegistry;


  constructor(address _registry) {
    s_feedRegistry = FeedRegistryInterface(_registry);
  }

  function getLatestPrice(address base, address quote)
  external
  view
  returns (int256 answer)
  {
    return s_feedRegistry.latestAnswer(base, quote);
  }
}

Hardhat/ Ethers​

getPriceFromTestnetRegistry.ts
import { ethers } from "hardhat";

async function main() {
  const registryAddress = "0x1647a10D50e1Ebf84FF6E38e4c8dd1298E0E69cC"; //Testnet address
  //Pass the name or ABI of the contract
  const registry = await ethers.getContractAt("FeedRegistryInterface", registryAddress);
  const priceWithoutDecimals = await registry.latestAnswerByName("BTC", "USD");
  console.log("Answer for BTC/USD: ", priceWithoutDecimals.toString());
}

main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

JavaScript​

getPriceFromTestnetRegistry.js
import Web3 from 'web3'
import contract_abi from './contract_abi.json'

async function getSymbolPairPrice(baseAsset, quoteAsset) {
  const registryAddress = "0x1647a10D50e1Ebf84FF6E38e4c8dd1298E0E69cC"; //Testnet address
  const provider = new Web3.providers.HttpProvider('https://data-seed-prebsc-1-s1.binance.org:8545');
  const web3 = new Web3(provider);
  const contract = new web3.eth.Contract(contract_abi, registryAddress);
  const result = await contract.methods.latestRoundDataByName(baseAsset, quoteAsset).call();
  console.log(result)
}

getSymbolPairPrice("BTC", "USD")

/** Output
  Result {
    '0': '18446744073709551616',
    '1': '1936203781166',
    '2': '1666108882',
    '3': '1666108887',
    '4': '18446744073709551616',
    roundId: '18446744073709551616',
    answer: '1936203781166',
    startedAt: '1666108882',
    updatedAt: '1666108887',
    answeredInRound: '18446744073709551616'
  }
*/
Contract ABI

The ABI json can be exported from the BSC Scan from the 'Contract ABI' section at a specific address.

Contract addresses​

FeedRegistry is deployed on BNB Testnet and Mainnet. Please refer to the contract addresses