The Kaiko Oracle

This guide walks you through consuming our Robust Pair Prices through the Kaiko Oracle on Ethereum. Several asset pairs are publicly available, meaning you can access free hourly updates or update on-demand for a small fee. You can read more about the Kaiko Oracle here.

Read and update manually

Visit oracle.kaiko.com. Here, you can see the latest Kaiko price updates for all pairs.

To update the price:

1. Click "connect wallet"

2. Once you've connected your wallet, click "Update"

3. Authorize the payment of 0.01 ETH

4. Wait a few seconds for the prices to be updated

One price update request updates all Kaiko price feeds - there's no need to request them independently.

Update and read on-chain

To read and update on-chain, you'll need to set up an off-chain listening event using a node provider of your choice to connect to the blockchain.

To update the price:

This example script uses Typescript, but you can produce similar results using other coding languages. Running the script requests a price update and listens until it's been updated on-chain. When the update is detected, it alerts your on-chain smart contract.

1. Install ethers npm install ethers

2. Send a transaction with a value of 0.01 ETH to the refreshPriceFeeds contract address 0xff2743c44f820c64c94eccfc1b497a1019541097

import { ethers } from 'ethers';

// Set up your Ethereum provider
const provider = new ethers.providers.JsonRpcProvider("<YOUR_PROVIDER_URL>");

// Initialize wallet using private key and connect it to the provider
const wallet = new ethers.Wallet("<YOUR_PRIVATE_KEY>", provider);

// Smart contract address
const contractAddress = "0xff2743c44f820c64c94eccfc1b497a1019541097";

// ABI definition of the contract's refreshPriceFeeds method
const abi = [
    "function refreshPriceFeeds() payable external"
];

// Create an instance of the contract
const contract = new ethers.Contract(contractAddress, abi, wallet);

async function refreshPriceFeeds() {
    try {
        // Define the amount of ETH to send (0.01 ETH)
        const amountToSend = ethers.utils.parseEther("0.01");

        // Call the refreshPriceFeeds function, sending 0.01 ETH
        const tx = await contract.refreshPriceFeeds({
            value: amountToSend // Send 0.01 ETH
        });

        // Wait for the transaction to be mined
        console.log("Transaction sent. Waiting for confirmation...");
        const receipt = await tx.wait();

        console.log("Transaction confirmed, receipt:", receipt);
    } catch (error) {
        console.error("Error while calling refreshPriceFeeds:", error);
    }
}

// Call the function
refreshPriceFeeds();

1. Wait for at least one block for the price update to be reflected on-chain

One price update request updates all Kaiko price feeds - there's no need to request them independently.

Read the price on-chain:

This Solidity contract example is triggered by the refreshPriceFeeds function in the Typescript example above. When triggered, it ingests the updated prices on-chain.

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

interface IExternalContract {
    function latestUpdate() external view returns (uint256 price, uint256 decimals, uint256 updatedAt);
}

contract CallLatestUpdate {
    address public externalContractAddress = <PRICE_CONTRACT_ADDRESS>;

    // Function to call the latestUpdate() function on the external contract
    function getLatestUpdate() public view returns (uint256 price, uint256 decimals, uint256 updatedAt) {
        // Create an instance of the external contract using the interface
        IExternalContract externalContract = IExternalContract(externalContractAddress);
        
        // Call the latestUpdate() function on the external contract
        return externalContract.latestUpdate();
    }
}

Although one price update refreshes all prices on-chain, you must read each price feed individually. See the price feeds and their corresponding addresses at oracle.kaiko.com.