Oracles

ThunderCore oracle provides a series of asset prices on the chain to make your smart contract connect with real world.

For projects already integrated with Chainlink data feed , we are providing the same function interfaces to make your project cross-chain onto ThunderCore instantly.

Pending for Review

This is pre-release version section. Contents can be changed anytime, please use in your caution.

Get Started

You can get the latest contract interfaces and ABIs through npm:

$ npm install @thundercore/oracle

or Yarn:

$ yarn add @thundercore/oracle

And just a few lines of code, so you can get the latest price:

import { FeedRegistryConsumerInterface } from '@thundercore/oracle/TTOracle.sol';

contract MyProject {
    address public constant TT_ORACLE = 0xD477d4d8132C6fce38f0bf38f46FcB62D6c5ddaE;

    function getThunderTokenPrice() public view returns (int256) {
        (
            /* uint80 roundId */,
            int256 answer,
            /* uint256 startedAt */,
            /* uint256 updatedAt */,
            /* uint80 answeredInRound */
        ) = FeedRegistryConsumerInterface(TT_ORACLE)
                .latestRoundData('TT/USDT');

        return answer;
    }
}

import { FeedRegistryInterface } from "@chainlink/contracts/src/v0.8/interfaces/FeedRegistryInterface.sol";
import { Denominations } from '@thundercore/oracle/TTOracle.sol';

contract MyProject {
    address public constant TT_ORACLE = 0xD477d4d8132C6fce38f0bf38f46FcB62D6c5ddaE;

    function getThunderTokenPrice() public view returns (int256) {
        (
            /* uint80 roundId */,
            int256 answer,
            /* uint256 startedAt */,
            /* uint256 updatedAt */,
            /* uint80 answeredInRound */
        ) = FeedRegistryInterface(TT_ORACLE)
                .latestRoundData(
                    Denominations.TT,
                    Denominations.USDT
                );

        return answer;
    }
}

# npm exec -- truffle console --network thundercore
# or
# yarn truffle console --network thundrcore
truffle(thundercore)> const abi = require('@thundercore/oracle/abi/FeedRegistryConsumerInterface.json')

truffle(thundercore)> const oracle = new web3.eth.Contract(abi, TT_ORACLE)

truffle(thundercore)> oracle.methods.latestRoundData('TT/USDT').call().then(res => res.answer).then(web3.utils.fromWei)
'0.01663655'

# npm exec -- hardhat console --network thundercore
# or
# yarn truffle console --network thundrcore
> const abi = require('@thundercore/oracle/abi/FeedRegistryConsumerInterface.json')

> const oracle = new hre.ethers.Contract(TT_ORACLE, abi, hre.ethers.provider)

> await oracle.latestRoundData('TT/USDT').then(res => res.answer).then(hre.ethers.utils.formatEther)
'0.01663655'

You can try it on ThunderCore testnet:

Using Data Feeds

Data Feeds are the quickest way to connect with the real-world asset prices.

Feed Registry

You can use the Feed Registry to reference data feed assets by pair name or currency identifier.

Solidity

To consume price data, your smart contract should reference DataFeedConsumerInterface, which defines the external functions implemented by Data Feeds.

If you've applied Chainlink aggregator in your service, i.e. AggregatorInterface, AggregatorV3Interface, or AggregatorV2V3Interface, you don't have to change the interface. The only difference is the feed address, just change it and test the result on the fly.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8;

import { DataFeedConsumerInterface } from "@thundercore/oracle/TTOracle.sol";

contract PriceConsumer {

    DataFeedConsumerInterface internal priceFeed;

    /**
     * Network: ThunderCore testnet [18]
     * Pair: TT/USDT
     * Address: 0x1Ce18a95C56Db619C070AeF58918EaB09FE2634c
     */
    constructor() {
        priceFeed = DataFeedConsumerInterface(0x1Ce18a95C56Db619C070AeF58918EaB09FE2634c);
    }

    /**
     * Returns the latest price
     */
    function getLatestPrice() public view returns (int256) {
        (
            /* uint80 roundID */,
            int256 price,
            /* uint256 startedAt */,
            /* uint256 updatedAt */,
            /* uint80 answeredInRound */
        ) = priceFeed.latestRoundData();

        return price;
    }
}

The latestRoundData function returns five values representing information about the latest price data. See the Data Feeds API Reference for more details.

ECMAScript (JavaScript)

const Web3 = require('web3')
const web3 = new Web3('https://testnet-rpc.thundercore.com')
const abi = require('@thundercore/oracle/abi/DataFeedConsumerInterface.json')
const address = '0x1Ce18a95C56Db619C070AeF58918EaB09FE2634c'
const priceFeed = new web3.eth.Contract(abi, address)

priceFeed.methods.latestRoundData().call()
    .then(res => res.answer)
    .then(web3.utils.fromWei)
    .then((price) => { console.log(price) })

const { ethers } = require('ethers')
const provider = new ethers.providers.JsonRpcProvider('https://testnet-rpc.thundercore.com')
const abi = require('@thundercore/oracle/abi/DataFeedConsumerInterface.json')
const address = '0x1Ce18a95C56Db619C070AeF58918EaB09FE2634c'
const priceFeed = new ethers.Contract(address, abi, provider)

priceFeed.latestRoundData()
    .then(({ answer }) => { console.log(ethers.utils.formatEther(answer)) })

Python

This example uses Web3.py to retrieve feed data from the TT/USDT feed on the ThunderCore testnet network.

from web3 import Web3
web3 = Web3(Web3.HTTPProvider('https://testnet-rpc.thundercore.com'))
abi = '[{"anonymous":false,"inputs":[{"indexed":true,"internalType":"int256","name":"current","type":"int256"},{"indexed":true,"internalType":"uint256","name":"roundId","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"updatedAt","type":"uint256"}],"name":"AnswerUpdated","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"uint256","name":"roundId","type":"uint256"},{"indexed":true,"internalType":"address","name":"startedBy","type":"address"},{"indexed":false,"internalType":"uint256","name":"startedAt","type":"uint256"}],"name":"NewRound","type":"event"},{"inputs":[],"name":"decimals","outputs":[{"internalType":"uint8","name":"","type":"uint8"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"description","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"version","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint80","name":"roundId","type":"uint80"}],"name":"hasRoundData","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint80","name":"_roundId","type":"uint80"}],"name":"getRoundData","outputs":[{"internalType":"uint80","name":"roundId","type":"uint80"},{"internalType":"int256","name":"answer","type":"int256"},{"internalType":"uint256","name":"startedAt","type":"uint256"},{"internalType":"uint256","name":"updatedAt","type":"uint256"},{"internalType":"uint80","name":"answeredInRound","type":"uint80"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"latestRoundData","outputs":[{"internalType":"uint80","name":"roundId","type":"uint80"},{"internalType":"int256","name":"answer","type":"int256"},{"internalType":"uint256","name":"startedAt","type":"uint256"},{"internalType":"uint256","name":"updatedAt","type":"uint256"},{"internalType":"uint80","name":"answeredInRound","type":"uint80"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint80","name":"roundId","type":"uint80"}],"name":"getPreviousRoundId","outputs":[{"internalType":"uint80","name":"","type":"uint80"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint80","name":"roundId","type":"uint80"}],"name":"getNextRoundId","outputs":[{"internalType":"uint80","name":"","type":"uint80"}],"stateMutability":"view","type":"function"}]'
addr = '0x1Ce18a95C56Db619C070AeF58918EaB09FE2634c'
contract = web3.eth.contract(address=addr, abi=abi)
latestData = contract.functions.latestRoundData().call()
print(latestData)

Getting a different price denomination

If you require a denomination other than what we have provided, you can use two data feeds to derive the pair that you need. For example, if you need a TT/ETH price, you could take the TT/USDT feed and the ETH/USDT feed and derive TT/ETH using division.

\frac{TT / USDT}{ETH / USDT} = \frac{TT / \sout{USDT}}{ETH / \sout{USDT}} = TT / ETH

Historical Price Data

The most common use case for data feeds is to get the latest price. However, we also exposes functions which can be used to retrieve price data of a previous round ID.

Never over rely on previous round data of oracle

If your project requires price before one week or longer ago, always store those prices inside your smart contract.

In ThunderCore oracle, we guarantee to keeps one recent week prices. And after one week, those data could be purged anytime.

Solidity

// SPDX-License-Identifier: MIT
pragma solidity ^0.8;

import { DataFeedConsumerInterface } from "@thundercore/oracle/TTOracle.sol";

contract HistoricalPriceConsumer {

    DataFeedConsumerInterface internal priceFeed;

    /**
     * Network: ThunderCore testnet [18]
     * Pair: TT/USDT
     * Address: 0x1Ce18a95C56Db619C070AeF58918EaB09FE2634c
     */
    constructor() {
        priceFeed = DataFeedConsumerInterface(0x1Ce18a95C56Db619C070AeF58918EaB09FE2634c);
    }

    /**
     * Returns historical price for a round id
     */
    function getHistoricalPrice(uint80 roundId) public view returns (int256) {
        require(priceFeed.hasRoundData(roundId), 'No this round data');

        (
            /* uint80 roundID */,
            int256 price,
            /* uint256 startedAt */,
            /* uint256 updatedAt */,
            /* uint80 answeredInRound */
        ) = priceFeed.getRoundData(roundId);

        return price;
    }
}

ECMAScript (JavaScript)

const Web3 = require('web3')
const web3 = new Web3('https://testnet-rpc.thundercore.com')
const abi = require('@thundercore/oracle/abi/DataFeedConsumerInterface.json')
const address = '0x1Ce18a95C56Db619C070AeF58918EaB09FE2634c'
const priceFeed = new web3.eth.Contract(abi, address)

priceFeed.methods.getRoundData(1).call()
    .then(res => res.answer)
    .then(web3.utils.fromWei)
    .then((price) => { console.log(price) })

const { ethers } = require('ethers')
const provider = new ethers.providers.JsonRpcProvider('https://testnet-rpc.thundercore.com')
const abi = require('@thundercore/oracle/abi/DataFeedConsumerInterface.json')
const address = '0x1Ce18a95C56Db619C070AeF58918EaB09FE2634c'
const priceFeed = new ethers.Contract(address, abi, provider)

priceFeed.getRoundData(1)
    .then(({ answer }) => { console.log(ethers.utils.formatEther(answer)) })

Python

from web3 import Web3
web3 = Web3(Web3.HTTPProvider('https://testnet-rpc.thundercore.com'))
abi = '[{"anonymous":false,"inputs":[{"indexed":true,"internalType":"int256","name":"current","type":"int256"},{"indexed":true,"internalType":"uint256","name":"roundId","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"updatedAt","type":"uint256"}],"name":"AnswerUpdated","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"uint256","name":"roundId","type":"uint256"},{"indexed":true,"internalType":"address","name":"startedBy","type":"address"},{"indexed":false,"internalType":"uint256","name":"startedAt","type":"uint256"}],"name":"NewRound","type":"event"},{"inputs":[],"name":"decimals","outputs":[{"internalType":"uint8","name":"","type":"uint8"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"description","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"version","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint80","name":"roundId","type":"uint80"}],"name":"hasRoundData","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint80","name":"_roundId","type":"uint80"}],"name":"getRoundData","outputs":[{"internalType":"uint80","name":"roundId","type":"uint80"},{"internalType":"int256","name":"answer","type":"int256"},{"internalType":"uint256","name":"startedAt","type":"uint256"},{"internalType":"uint256","name":"updatedAt","type":"uint256"},{"internalType":"uint80","name":"answeredInRound","type":"uint80"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"latestRoundData","outputs":[{"internalType":"uint80","name":"roundId","type":"uint80"},{"internalType":"int256","name":"answer","type":"int256"},{"internalType":"uint256","name":"startedAt","type":"uint256"},{"internalType":"uint256","name":"updatedAt","type":"uint256"},{"internalType":"uint80","name":"answeredInRound","type":"uint80"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint80","name":"roundId","type":"uint80"}],"name":"getPreviousRoundId","outputs":[{"internalType":"uint80","name":"","type":"uint80"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint80","name":"roundId","type":"uint80"}],"name":"getNextRoundId","outputs":[{"internalType":"uint80","name":"","type":"uint80"}],"stateMutability":"view","type":"function"}]'
addr = '0x1Ce18a95C56Db619C070AeF58918EaB09FE2634c'
contract = web3.eth.contract(address=addr, abi=abi)
roundData = contract.functions.getRoundData(1).call()
print(roundData)

Feed Registry

The Feed Registry is an on-chain mapping of assets to feeds. It enables you to query data feeds from asset addresses directly, without needing to know the feed contract addresses.

Base and Quote

You are free to choose querying feeds from their pair names, e.g. TT/USDT; or you can keep Chainlink style by token addresses.

registry.latestRoundData('TT/USDT');

registry.latestRoundData(
    Denominations.TT,
    Denominations.USDT
);

Solidity example code

// SPDX-License-Identifier: MIT
pragma solidity ^0.8;

import { FeedRegistryInterface } from '@thundercore/oracle/TTOracle.sol';

contract PriceConsumer {
    FeedRegistryInterface internal registry;

    /**
     * Network: ThunderCore testnet
     * Feed Registry: 0xD477d4d8132C6fce38f0bf38f46FcB62D6c5ddaE
     */
    constructor(address _registry) {
        registry = FeedRegistryInterface(_registry);
    }

    /**
     * Returns the TT / USDT price
     */
    function getTTPrice() public view returns (int) {
        (
            uint80 roundID,
            int256 price,
            uint256 startedAt,
            uint256 timeStamp,
            uint80 answeredInRound
        ) = registry.latestRoundData('TT/USDT');
        return price;
    }
}

ECMAScript (JavaScript) example

const Web3 = require('web3')
const web3 = new Web3('https://testnet-rpc.thundercore.com')
const abi = require('@thundercore/oracle/abi/FeedRegistryConsumerInterface.json')
const address = '0xD477d4d8132C6fce38f0bf38f46FcB62D6c5ddaE'
const registry = new web3.eth.Contract(abi, address)

registry.methods.latestRoundData('TT/USDT').call()
    .then(res => res.answer)
    .then(web3.utils.fromWei)
    .then((price) => { console.log(price) })

API Reference

API reference for DataFeedConsumerInterface.

Name

Description

decimals

Get the decimals of "answer" in responsed round data

function decimals() external view returns (uint8)

RETURN: The number of decimals.

description

Get the feed pair name, format "${BASE}/${QUOTE}"

function description() external view returns (string memory);

RETURN: The pair name of data feed.

version

Get the code version of the feed proxy points to

function version() external view returns (uint256);

RETURN: The code version.

hasRoundData

Check if the round data existed

function hasRoundData(uint80 roundId) external view returns (bool);

Petermeters
- roundId: The round ID to check if round data existed in data feed.
Return Values
- RETURN: Round data exists or not.

getRoundData

Get data from a specific round

function getRoundData(uint80 _roundId)
    external
    view
    returns (
        uint80 roundId,
        int256 answer,
        uint256 startedAt,
        uint256 updatedAt,
        uint80 answeredInRound
    );

Petermeters
- roundId: The round ID
Return Values
- roundId: The round ID.
- answer: The price.
- startedAt: Timestamp of when the round started.
- updatedAt: Timestamp of when the round was last updated.
- answeredInRound: The round ID of the round in which the answer was computed.

latestRoundData

Get data from the latest round

function latestRoundData()
    external
    view
    returns (
        uint80 roundId,
        int256 answer,
        uint256 startedAt,
        uint256 updatedAt,
        uint80 answeredInRound
    );

Return Values
- roundId: The round ID.
- answer: The price.
- startedAt: Timestamp of when the round started.
- updatedAt: Timestamp of when the round was last updated.
- answeredInRound: The round ID of the round in which the answer was computed.

getPreviousRoundId

Get previous data existed round ID

function getPreviousRoundId(uint80 roundId) external view returns (uint80);

Petermeters
- roundId: The round ID to look up closest previous valid round ID.
Return Values
- RETURN: The previous valid round ID to parameter specified round ID; return 0 if no valid round ID before.

getNextRoundId

Get next data existed round ID

function getNextRoundId(uint80 roundId) external view returns (uint80);

Petermeters
- roundId: The round ID to look up closest next valid round ID.
Return Values
- RETURN: The next valid round ID to parameter specified round ID; return 0 if no valid round ID after.

Contract Addresses

FeedRegistry: 0x70B3B30066b4F7B927f26C408461b3F176AA07Dc

Pair

Dec

Proxy

FeedRegistry: 0xD477d4d8132C6fce38f0bf38f46FcB62D6c5ddaE

Pair

Dec

Proxy

Last updated 1 year ago