Posted By : Yogesh
Smart contract development plays a crucial role in oracle development and enables the seamless integration of real-world data into blockchain networks. With smart contracts, oracles can securely and autonomously retrieve and verify external data. Let's explore the process of developing an oracle using an Ethereum smart contract.
Oracles were created to enhance the possibilities of collaboration on blockchains. They establish connections between blockchains and external systems, enabling access to data from off-chain sources. Oracles act as a trusted source of information for the blockchain, providing secure gateways to off-chain systems. This allows smart contract applications to verify external events and trigger actions on external services.
Oracles essentially function as a link between two environments: the on-chain environment representing the blockchain network and the off-chain environment representing external systems in the real world.
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pragma solidity >=0.7.0 <0.9.0;
import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";
contract EthPrice {
AggregatorV3Interface internal ethFeed;
bytes32 ethHash = keccak256(abi.encodePacked("ETH"));
constructor(_address) {
ethFeed = AggregatorV3Interface(_address);
}
function getEthPrice() public view returns (int) {(
uint80 roundID,
int price,
uint startedAt,
uint timeStamp,
uint80 answeredInRound
) = ethFeed.latestRoundData();
return price;
}
}
To get the address _address(Price feed contract address) of click here
Deploy the contract from the Deployment tab in Remix and run the function.
This code represents a Solidity smart contract called EthPrice
that retrieves the latest price of Ethereum (ETH) using a Chainlink price feed.
Here's a breakdown of the code:
pragma
statement defines the version range of Solidity that the contract is compatible with.import
statement imports the AggregatorV3Interface
from the Chainlink library. This interface provides functions to interact with Chainlink price feed contracts.EthPrice
contract has an internal variable ethFeed
of type AggregatorV3Interface
. It will be used to interact with the Chainlink price feed.ethHash
variable stores the keccak256 hash of the string "ETH". This can be used as an identifier or key for Ethereum.constructor
function is used to initialize the contract. It takes an _address
parameter representing the address of the Chainlink price feed contract. It assigns the provided address to ethFeed
.getEthPrice
function is a view function that retrieves the latest ETH price from the Chainlink price feed. It returns the price as an int
.
latestRoundData
function from the ethFeed
contract.latestRoundData
function fetches the latest round data from the Chainlink price feed.price
value is extracted from the tuple and returned.
In summary, the EthPrice
contract interacts with a Chainlink price feed to retrieve the latest price of Ethereum (ETH) and provides a function getEthPrice
to access this price from other contracts or externally.
Interested in Oracle development using smart contracts? Connect with our smart contract developers to get started.
November 19, 2024 at 12:29 pm
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