Read and API3 dAPI Price feed to your contract

This project covers two topics.

How to get your smart contract to read a price feed from a proxy available from https://market.api3.org/dapis
How to deploy an adaptor to utilize API3 dAPIs without having to refactor your code if you use another library.

Files

API3PriceFeed.sol - Base contract setup to receive an API3 price feed
OtherOracle.sol - Simple contract that receives other popular oracles in their native format
Adaptor.sol - The adaptor contract the converts the API3 price feed data to match the format that is required by the other oracle contract.
Mock Folders - Contracts that just return fake data in API3 oracle format and AggregatorV3 format

How to Execute a Price Feed Read

Deploy the API3PriceFeed.sol contract. Once deployed, you want to choose the price feed you want to read in your contract by going to https://market.api3.org/dapis

Call the setProxyAddress with the address for the price feed. You can then read the data by calling readDataFeed

npx hardhat ignition deploy ignition/modules/API3PriceFeed.js --network sepolia

You also have the option to verify all deployed contracts after deployment with:

npx hardhat ignition verify chain-11155111

Using API3 price oracle with other Oracle formats

Deploy the other oracle smart contract

You will need to deploy the OtherOracle contract using the other oracle setup. We have it set to default the ETH/USD price feed on Sepolia

npx hardhat ignition deploy ignition/modules/OtherOracle.js --network sepolia

How to use the adaptor

Deploy the Adaptor.sol contract with the the proxy contract address (API3 Marketplace) that you want it to adapt to the deployed OtherOracle contract. For this demo, we are using ETH/USD price feed on Sepolia.

npx hardhat ignition deploy ignition/modules/Adaptor.js --network sepolia

Once you have deployed your Adaptor contract, you will use that deployed contract address

Example:
Deploy#Api3AggregatorAdaptor - 0xBf35d6060d828E573bf10cB0a30D2dab710D5075

Input the deployed Api3AggregatorAdaptor address onto the updateOracleSource function of the OtherOracle contract.

Once that is completed, your OtherOracle contract will be able to read API3 Price Feeds without a refactor

Testing

You can test the scenario locally with

npx hardhat test

It will take you through the mock tests and show you the flow of setting the adaptor as mentions above and the ability to look a the price feed data intregaton.

it("Reads from API3 Oracle through adapter", async function () {
        const { api3oracle, otherOracle, adaptor, mockDapi, owner } = await loadFixture(deployBefore);
        await otherOracle.updateOracleSource(adaptor.getAddress());
        let { roundId, answer, startedAt, timestamp, answeredInRound } = await otherOracle.getLatestAnswer();
        console.log("Answer: ", answer.toString());
        console.log("Answered in Round: ", answeredInRound.toString());
    });

It will console out the original price feed data from the other oracle format and then console log the adjusted format need to be used by the other oracle contract

    Other Oracle
Answer:  1000
      ✔ Read Other Oracle
Answer:  100000000000
Answered in Round:  18446744073709562881
      ✔ Reads from API3 Oracle through adapter