getValue Method

Using DIAOracleV2 Interface

The following is an example of how to retrieve price value from a standard DIA price oracle. For the purpose of this example, we will be using the following demo oracle on Ethereum: 0xCD5F…f3cB.

Access any DIA price 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 2 values:

The current asset’s price in USD with a fix-comma notation of 8 decimals.
The UNIX timestamp of the last oracle update.

pragma solidity ^0.8.13;

interface IDIAOracleV2 {
    function getValue(string memory) external view returns (uint128,
             uint128);
}

contract DIAOracleSample {

    address diaOracle;

    constructor(address _oracle) {
        diaOracle = _oracle;
    }

    function getPrice(string memory key)
    external
    view
    returns (
        uint128 latestPrice,
        uint128 timestampOflatestPrice
    ) {
        (latestPrice, timestampOflatestPrice) =
                 IDIAOracleV2(diaOracle).getValue(key);
    }
}

Always check the returned timestamp before using the price. DIA oracles do not revert on old data. Use getPriceIfNotOlderThan below, or see Check Price Freshness.

Find the detailed description of the functions and how to run tests on our GitHub page:

GitHub - diadata-org/DIA-integration-sample

Solidity integration example

Using Solidity Library

DIA has a dedicated Solidity library to facilitate the integration of DIA price oracles in your own contracts. The library consists of two functions, getPrice and getPriceIfNotOlderThan.

Access the library

import { DIAOracleLib } from "./libraries/DIAOracleLib.sol";

Methods

getPrice

function getPrice(
        address oracle,
        string memory key
        )
        public
        view
        returns (uint128 latestPrice, uint128 timestampOflatestPrice);

Returns the price of a specified asset along with the update timestamp. Parameters:

Name	Type	Description
oracle	address	Address of the oracle that we want to use
key	string	The asset that we want to use e.g. “ETH/USD”

Return Values:

Name	Type	Description
latestPrice	uint128	Price of the specified asset returned by the DIAOracle
timestampOflatestPrice	uint128	The update timestamp of the latest price

getPriceIfNotOlderThan

function getPriceIfNotOlderThan(
        address oracle,
        string memory key,
        uint128 maxTimePassed
        )
        public
        view
        returns (uint128 price, bool inTime)
    {

Checks if the oracle price is older than maxTimePassed Parameters:

Name	Type	Description
oracle	address	Address of the oracle that we want to use
key	string	The asset that we want to use e.g. “ETH/USD”
maxTimePassed	uint128	The maximum acceptable time passed in seconds since the the price was updated

Return Values:

Name	Type	Description
price	uint128	Price of the specified asset returned by the DIAOracle
inTime	bool	A boolian that is `true` if the price was updated at most maxTimePassed seconds ago, otherwise `false`

Find a detailed integration example and how to run a test on our GitHub page:

GitHub - diadata-org/DIAOracleLib

Sample contract

pragma solidity ^0.8.13;

import { DIAOracleLib } from "./libraries/DIAOracleLib.sol";

contract DIAOracleSample {
    error PriceTooOld();

    address diaOracle;

    constructor(address _oracle) {
        diaOracle = _oracle;
    }

    function getPrice(
        string memory key
    ) external view returns (uint128 latestPrice) {
        (latestPrice, ) = DIAOracleLib.getPrice(diaOracle, key);
    }

    function checkPriceAge(
        string memory key,
        uint128 maxTimePassed
    ) external view returns (uint128 price) {
        bool inTime;
        (price, inTime) = DIAOracleLib.getPriceIfNotOlderThan(
            diaOracle,
            key,
            maxTimePassed
        );

        if (!inTime) revert PriceTooOld();
    }
}

How-to Guides

Chain-specific Guides

Methodologies

General Guides

Resources

Using DIAOracleV2 Interface

GitHub - diadata-org/DIA-integration-sample

Using Solidity Library

Access the library

Methods

getPrice

getPriceIfNotOlderThan

GitHub - diadata-org/DIAOracleLib

Sample contract

​Using DIAOracleV2 Interface

GitHub - diadata-org/DIA-integration-sample

​Using Solidity Library

​Access the library

​Methods

​getPrice

​getPriceIfNotOlderThan

GitHub - diadata-org/DIAOracleLib

​Sample contract

Using DIAOracleV2 Interface

Using Solidity Library

Access the library

Methods

getPrice

getPriceIfNotOlderThan

Sample contract