Feed Registry

The Feed Registry serves as a blockchain-based directory that links assets to their corresponding data feeds. This system allows for direct querying of Blocksense data feeds using asset addresses, eliminating the need-to-know specific feed contract addresses. As a result, smart contracts can efficiently retrieve up-to-date asset prices through a single function call to a unified contract interface.

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The Feed Registry exclusively includes feeds associated with canonical token addresses on a given network. Feeds without a corresponding token address, such as those for stock indices, are not included in the registry due to the lack of a canonical token representation.

For a complete list of functions and parameters for the FeedRegistry contract, see the Feed Registry Reference Documentation.

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For a complete list of functions and parameters for the FeedRegistry contract, see the Feed Registry Reference Documentation.

Base and Quote

The Feed Registry maps feeds from base and quote address pairs. To get the latest WETH / USDC round data from the registry, call:

solidity

latestRoundData(address base, address quote)

For example, to get the latest WETH / USDC price:

base: The WETH token address on that network e.g. 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2 for WETH on Ethereum mainnet
quote: The USDC token address on Ethereum mainnet 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48

solidity

latestRoundData(0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2, 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48)

Code Examples

Solidity

To consume price data from the Feed Registry, your smart contract should reference IFeedRegistry, which defines the external functions implemented by the Feed Registry.

RegistryConsumer.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;
/**
 * THIS IS AN EXAMPLE CONTRACT THAT USES HARDCODED VALUES FOR CLARITY.
 * THIS IS AN EXAMPLE CONTRACT THAT USES UN-AUDITED CODE.
 * DO NOT USE THIS CODE IN PRODUCTION.
 */
contract RegistryConsumer {
  IFeedRegistry public immutable registry;
 
  constructor(address _registry) {
    registry = IFeedRegistry(_registry);
  }
 
  function getLatestPrice(
    address base,
    address quote
  ) external view returns (uint256) {
    return uint256(registry.latestAnswer(base, quote));
  }
 
  function getRoundData(
    address base,
    address quote,
    uint80 roundId
  ) external view returns (int256 _price, uint256 _lastUpdate) {
    (/*uint80 _roundId*/, _price, /*uint startedAt*/, _lastUpdate, /*uint80 answeredInRound*/) = registry.getRoundData(base, quote, roundId);
  }
}

Solidity Hardhat Example

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You can find a working Hardhat project here. Clone the repo and follow the setup instructions to run the example locally.

Ethers.js v6.x

To get latest price:

javascript

const registry = new ethers.Contract(contractAddress, abiJson, provider);
const price = await registry.latestAnswer(base, quote);

To get round data:

javascript

const registry = new ethers.Contract(contractAddress, abiJson, provider);
const [roundID, answer, startedAt, updatedAt, answeredInRound] =
  await registry.getRoundData(base, quote, roundId);

To get the ChainlinkProxy address responsible for a given feed:

javascript

const registry = new ethers.Contract(contractAddress, abiJson, provider);
const chainlinkProxyAddress = await registry.getFeed(base, quote);

Overview Chainlink Proxy