Partner Workshop: DIA

Ecosystem Price Oracles, powered by DIA

Introduction to DIA Oracles

DIA is a cross-chain oracle provider that sources granular market data from diverse exchanges, including CEXs, DEXs, and NFT marketplaces. Its data sourcing is thorough, enabling unparalleled transparency and customizability for resilient price feeds for 20,000+ assets. Its versatile data processing and delivery ensures adaptability and reliability for any decentralized application.

Usage of DIA Oracles on CrossFi

dApps building on CrossFi can utilize DIA oracles to obtain up-to-date asset price information. These deployed oracles are suitable for use in production environments. They come with a list of supported assets and settings. However, if dApps require a custom oracle with a different set of assets and configurations, they should contact DIA on Telegram.

Token Price Oracle

Deployed contracts

Access the oracles in the smart contracts below:

• CrossFi Testnet Oracle: 0x33df80cdf0c9ff686261b11263d9f4a3ccc3d07f

Included price feeds + data sources

The CrossFi oracle includes the following price feeds:

Asset Ticker	Asset Blockchain	Asset Address	Asset Sources Overview

WETH	Ethereum	0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2	WETH Sources
WBTC	Ethereum	0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599	WBTC Sources
USDT	Ethereum	0xdAC17F958D2ee523a2206206994597C13D831ec7	USDT Sources
DAI	Ethereum	0x6B175474E89094C44Da98b954EedeAC495271d0F	DAI Sources
USDC	Ethereum	0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48	USDC Sources
FRAX	Ethereum	0x853d955aCEf822Db058eb8505911ED77F175b99e	FRAX Sources
LINK	Ethereum	0x514910771AF9Ca656af840dff83E8264EcF986CA	LINK Sources
WBNB	Binance Smart Chain	0xbb4CdB9CBd36B01bD1cBaEBF2De08d9173bc095c	WBNB Sources
EURO	N/A	N/A	EURO Sources
XFI	Ethereum	0xC8CeED65E236F7d6fB378b8715f9e6912e486A54	XFI Sources

Learn more about DIA’s data sourcing and data computation architecture.

Oracle configuration settings

Oracle specifications:

Methodology: VWAPIR

The final price point for each asset is calculated by computing the assets' trade information across multiple DEXs and CEXs. This is done using a Volume Weighted Average Price with Interquartile Range (VWAPIR) methodology. Learn more about VWAPIR.

Update frequency: 24-hour heartbeat + 0.5% deviation threshold

A consistent heartbeat refreshes all asset prices every 2 minutes. Moreover, if the oracle detects a price fluctuation exceeding 0.5% from the last published rate, it promptly sends an update on-chain.

How to access DIA oracles?

Here is an example of how to access a price value on DIA oracles:

1. Access your custom oracle smart contract on CrossFi.

2. Call getValue(pair_name) with pair_name being the full pair name such as BTC/USD. You can use the "Read" section on the explorer to execute this call.

3. The response of the call contains two values:

4. 1. The current asset price in USD with a fix-comma notation of 8 decimals.

   2. The UNIX timestamp of the last oracle update.

You can find DIA's oracle integration samples in Solidity and Vyper languages by visiting:

→ Access the Oracle | DIA Documentation

Randomness Oracle

Deployed contracts

Access the oracles in the smart contracts below:

• CrossFi Testnet Oracle: 0xad19b5b3a0bf2bacf028ed6cc9e3fc153cb405b6

How to access the oracle

Anyone can access published random values via round ID.

{

"round": 1597683,

"randomness": "24138936fcbf7fc3951c928158be6998cee3af622142d0790333608d17a5c5f6",

"signature": "8c04905c0adf34f1fb007915d9ccc7d07b97305fc63952726f9367c87f36ab687c5e190c151f6ac4d760a9e009fc54230adb8513885449d649a229bc727be9ff347bdbce1c609cebf993b6ae57133fbcf23f96b15dbd3510cb5f2ade6b30b647",

"previous_signature": "ada42197a2db89866da4c44348f77f7868e41e961ec32e636b912d43c625386afae9e54944ac573047dbd227ee495b52059586c8d8cd0edfe18cc15ca0666a66651da1d62b12af2d0fac19735bed9298690a593571965c3ad7c7b11947e76ec0"

}

The DIA randomness smart contract is structured as follows:

pragma solidity ^0.8.0;

contract DIARandomOracle {

struct Random {

string randomness;

string signature;

string previousSignature;

}

mapping (uint256 => Random) public values;

uint256 public lastRound = 0;

address public oracleUpdater;

event OracleUpdate(string key, uint128 value, uint128 timestamp);

event UpdaterAddressChange(address newUpdater);

constructor() {

oracleUpdater = msg.sender;

}

function setRandomValue(uint256 _round, string memory _randomness, string memory _signature, string memory _previousSignature) public {

require(msg.sender == oracleUpdater,"not a updater");

require(lastRound<_round, "old round");

lastRound = _round;

values[_round] = Random(_randomness, _signature, _previousSignature);

}

function getValue(uint256 _round) external view returns (Random memory) {

return values[_round];

}

function updateOracleUpdaterAddress(address newOracleUpdaterAddress) public {

require(msg.sender == oracleUpdater,"not a updater");

oracleUpdater = newOracleUpdaterAddress;

emit UpdaterAddressChange(newOracleUpdaterAddress);

}

function getRandomValueFromRound(uint256 _round) external view returns (string memory) {

return values[_round].randomness;

}

function getRandomValueFromRoundWithSignature(uint256 _round) external view returns (Random memory) {

return values[_round];

}

function getLastRound() public view returns(uint256) {

return lastRound;

}

}

Users can call getLastRound() to obtain the ID of the latest published round. To obtain the randomness of a certain round, users can call getRandomValueFromRound(uint256 _round) using the obtaines round ID.

The signature can also be requested by calling getRandomValueFromRoundWithSignature(uint256 _round).

Please be aware that you should always let all inputs commit before any randomness is used in a later round. For example, if you build a lottery, only call randomness after the last participant has committed their stake. To show this in an example, we will build a simple dice game.

Make sure to never directly query the latest randomness value, otherwise the miner and the randomness oracle can interfere with the result. Always commit values before the randomness is used in a later round.

Support

For developer assistance, connect with the DIA team directly on Discord or Telegram.

Developers seeking other specialized, production-grade oracle with tailored price feeds and configurations can initiate the request by contacting the DIA BD Team via Telegram.