Blockchain oracles are third-party services or agents that provide smart contracts with external information and serve as bridges between blockchains and the external world. Because blockchains cannot access external data (outside of their network) due to their secure and deterministic nature, oracles are used to fetch, verify, and relay real-world data to smart contracts in a way that's trustworthy.
Oracles provide price feeds, enabling DeFi platforms to calculate token values, manage collateral, and execute liquidations. By sourcing data from various exchanges and financial platforms, oracles contribute to the robustness of DeFi applications.
Blockchain-based gaming and betting platforms use oracles to determine the outcomes of events, such as sports matches or random number generation. By connecting to various data sources and verifying results, oracles ensure fair and transparent gaming experiences.
Oracles can be employed in the insurance industry to automate claims processing and underwriting. They can fetch data related to weather conditions, flight delays, or health records, enabling insurers to create parametric insurance products. This reduces fraud and ensures quicker payouts based on predefined triggers.
and much more...
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DIA token price feeds provide smart contract real-time price information of 3,000+ cryptocurrencies, transparently sourced from 80+ trusted, high-volume DEXs and CEXs.
The feeds facilitate the development of DeFi use cases such as money markets, lending/borrowing, synthetic asset issuance, options, derivatives and futures markets, and many more.
Here is an example of how to retrieve price value from a standard DIA oracle. For the purpose of this example, we will be using the following demo oracle on Ethereum: 0xa935...5856.
Access any DIA oracle smart contract.
Call getValue(pair_name) with pair_name being the full pair name such as BTC/USD. You can use the "Read" section on Etherscan to execute this call.
The response of the call contains four values:
The current asset price in USD with a fix-comma notation of 8 decimals.
the UNIX timestamp of the last update.
Here is an example on how you can integrate DIA's oracle into your smart contract with Solidity:
Find more detailed description of the functions and how to run test in this
DIA has a dedicated Solidity library to facilitate integration of DIA oracles in your own contracts. The library consists of two functions, getPrice and getPriceIfNotOlderThan. You can learn more about the library and how to use it in the .
pragma solidity ^0.8.13;
interface IDIAOracleV2{
function getValue(string memory) external returns (uint128, uint128);
}
contract IntegrationSample{
address immutable ORACLE = 0xa93546947f3015c986695750b8bbEa8e26D65856;
uint128 public latestPrice;
uint128 public timestampOflatestPrice;
function getPriceInfo(string memory key) external {
(latestPrice, timestampOflatestPrice) = IDIAOracleV2(ORACLE).getValue(key);
}
function checkPriceAge(uint128 maxTimePassed) external view returns (bool inTime){
if((block.timestamp - timestampOflatestPrice) < maxTimePassed){
inTime = true;
} else {
inTime = false;
}
}
}