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Interfaces

Data Streams require several interfaces in order to retrieve and verify reports.

In the current code example for using Data Streams with Automation, these interfaces are specified in the example itself. Imports for these interfaces will be available in the future.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.16;

import {Common} from "@chainlink/contracts/src/v0.8/libraries/Common.sol";
import {StreamsLookupCompatibleInterface} from "@chainlink/contracts/src/v0.8/automation/interfaces/StreamsLookupCompatibleInterface.sol";
import {ILogAutomation, Log} from "@chainlink/contracts/src/v0.8/automation/interfaces/ILogAutomation.sol";
import {IRewardManager} from "@chainlink/contracts/src/v0.8/llo-feeds/interfaces/IRewardManager.sol";
import {IVerifierFeeManager} from "@chainlink/contracts/src/v0.8/llo-feeds/interfaces/IVerifierFeeManager.sol";
import {IERC20} from "@chainlink/contracts/src/v0.8/vendor/openzeppelin-solidity/v4.8.0/contracts/interfaces/IERC20.sol";

/**
 * THIS IS AN EXAMPLE CONTRACT THAT USES UN-AUDITED CODE FOR DEMONSTRATION PURPOSES.
 * DO NOT USE THIS CODE IN PRODUCTION.
 */

// Custom interfaces for IVerifierProxy and IFeeManager
interface IVerifierProxy {
    function verify(
        bytes calldata payload,
        bytes calldata parameterPayload
    ) external payable returns (bytes memory verifierResponse);

    function s_feeManager() external view returns (IVerifierFeeManager);
}

interface IFeeManager {
    function getFeeAndReward(
        address subscriber,
        bytes memory unverifiedReport,
        address quoteAddress
    ) external returns (Common.Asset memory, Common.Asset memory, uint256);

    function i_linkAddress() external view returns (address);

    function i_nativeAddress() external view returns (address);

    function i_rewardManager() external view returns (address);
}

contract StreamsUpkeep is ILogAutomation, StreamsLookupCompatibleInterface {
    struct BasicReport {
        bytes32 feedId; // The feed ID the report has data for
        uint32 validFromTimestamp; // Earliest timestamp for which price is applicable
        uint32 observationsTimestamp; // Latest timestamp for which price is applicable
        uint192 nativeFee; // Base cost to validate a transaction using the report, denominated in the chain’s native token (WETH/ETH)
        uint192 linkFee; // Base cost to validate a transaction using the report, denominated in LINK
        uint32 expiresAt; // Latest timestamp where the report can be verified on-chain
        int192 price; // DON consensus median price, carried to 8 decimal places
    }

    struct PremiumReport {
        bytes32 feedId; // The feed ID the report has data for
        uint32 validFromTimestamp; // Earliest timestamp for which price is applicable
        uint32 observationsTimestamp; // Latest timestamp for which price is applicable
        uint192 nativeFee; // Base cost to validate a transaction using the report, denominated in the chain’s native token (WETH/ETH)
        uint192 linkFee; // Base cost to validate a transaction using the report, denominated in LINK
        uint32 expiresAt; // Latest timestamp where the report can be verified on-chain
        int192 price; // DON consensus median price, carried to 8 decimal places
        int192 bid; // Simulated price impact of a buy order up to the X% depth of liquidity utilisation
        int192 ask; // Simulated price impact of a sell order up to the X% depth of liquidity utilisation
    }

    struct Quote {
        address quoteAddress;
    }

    event PriceUpdate(int192 indexed price);

    IVerifierProxy public verifier;

    address public FEE_ADDRESS;
    string public constant DATASTREAMS_FEEDLABEL = "feedIDs";
    string public constant DATASTREAMS_QUERYLABEL = "timestamp";
    int192 public last_retrieved_price;

    // This example reads the ID for the basic ETH/USD price report on Arbitrum Sepolia.
    // Find a complete list of IDs at https://docs.chain.link/data-streams/stream-ids
    string[] public feedIds = [
        "0x00027bbaff688c906a3e20a34fe951715d1018d262a5b66e38eda027a674cd1b"
    ];

    constructor(address _verifier) {
        verifier = IVerifierProxy(_verifier);
    }

    // This function uses revert to convey call information.
    // See https://eips.ethereum.org/EIPS/eip-3668#rationale for details.
    function checkLog(
        Log calldata log,
        bytes memory
    ) external returns (bool upkeepNeeded, bytes memory performData) {
        revert StreamsLookup(
            DATASTREAMS_FEEDLABEL,
            feedIds,
            DATASTREAMS_QUERYLABEL,
            log.timestamp,
            ""
        );
    }

    // The Data Streams report bytes is passed here.
    // extraData is context data from feed lookup process.
    // Your contract may include logic to further process this data.
    // This method is intended only to be simulated off-chain by Automation.
    // The data returned will then be passed by Automation into performUpkeep
    function checkCallback(
        bytes[] calldata values,
        bytes calldata extraData
    ) external pure returns (bool, bytes memory) {
        return (true, abi.encode(values, extraData));
    }

    // function will be performed on-chain
    function performUpkeep(bytes calldata performData) external {
        // Decode the performData bytes passed in by CL Automation.
        // This contains the data returned by your implementation in checkCallback().
        (bytes[] memory signedReports, bytes memory extraData) = abi.decode(
            performData,
            (bytes[], bytes)
        );

        bytes memory unverifiedReport = signedReports[0];

        (, /* bytes32[3] reportContextData */ bytes memory reportData) = abi
            .decode(unverifiedReport, (bytes32[3], bytes));

        // Report verification fees
        IFeeManager feeManager = IFeeManager(address(verifier.s_feeManager()));
        IRewardManager rewardManager = IRewardManager(
            address(feeManager.i_rewardManager())
        );

        address feeTokenAddress = feeManager.i_linkAddress();
        (Common.Asset memory fee, , ) = feeManager.getFeeAndReward(
            address(this),
            reportData,
            feeTokenAddress
        );

        // Approve rewardManager to spend this contract's balance in fees
        IERC20(feeTokenAddress).approve(address(rewardManager), fee.amount);

        // Verify the report
        bytes memory verifiedReportData = verifier.verify(
            unverifiedReport,
            abi.encode(feeTokenAddress)
        );

        // Decode verified report data into BasicReport struct
        BasicReport memory verifiedReport = abi.decode(
            verifiedReportData,
            (BasicReport)
        );

        // Log price from report
        emit PriceUpdate(verifiedReport.price);

        // Store the price from the report
        last_retrieved_price = verifiedReport.price;
    }

    fallback() external payable {}
}

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