feat: coinbase api oracle and api adapter (#6)

Signed-off-by: Pablo Maldonado <pablo@umaproject.org>
Signed-off-by: Matt Rice <matthewcrice32@gmail.com>
Signed-off-by: Reinis Martinsons <reinis@umaproject.org>
Co-authored-by: Matt Rice <matthewcrice32@gmail.com>
Co-authored-by: Reinis Martinsons <reinis@umaproject.org>
Co-authored-by: chrismaree <christopher.maree@gmail.com>
Co-authored-by: Reinis Martinsons <77973553+Reinis-FRP@users.noreply.github.com>

src/adapters/source-adapters/CoinbaseSourceAdapter.sol

@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: BUSL-1.1
+pragma solidity 0.8.17;
+
+import {DecimalLib} from "../lib/DecimalLib.sol";
+import {IAggregatorV3SourceCoinbase} from "../../interfaces/coinbase/IAggregatorV3SourceCoinbase.sol";
+import {DiamondRootOval} from "../../DiamondRootOval.sol";
+
+/**
+ * @title CoinbaseSourceAdapter
+ * @notice A contract to read data from CoinbaseOracle and standardize it for Oval.
+ * @dev Can fetch information from CoinbaseOracle source at a desired timestamp for historic lookups.
+ */
+abstract contract CoinbaseSourceAdapter is DiamondRootOval {
+    IAggregatorV3SourceCoinbase public immutable COINBASE_SOURCE;
+    uint8 private immutable SOURCE_DECIMALS;
+    string public TICKER;
+
+    event SourceSet(address indexed sourceOracle, uint8 indexed sourceDecimals, string ticker);
+
+    constructor(IAggregatorV3SourceCoinbase _source, string memory _ticker) {
+        COINBASE_SOURCE = _source;
+        SOURCE_DECIMALS = _source.decimals();
+        TICKER = _ticker;
+
+        emit SourceSet(address(_source), SOURCE_DECIMALS, TICKER);
+    }
+
+    /**
+     * @notice Tries getting the latest data as of the requested timestamp.
+     * If this is not possible, returns the earliest data available past the requested timestamp within provided traversal limitations.
+     * @param timestamp The timestamp to try getting the latest data at.
+     * @param maxTraversal The maximum number of rounds to traverse when looking for historical data.
+     * @return answer The answer as of the requested timestamp, or the earliest available data if not available, in 18 decimals.
+     * @return updatedAt The timestamp of the answer.
+     */
+    function tryLatestDataAt(uint256 timestamp, uint256 maxTraversal)
+        public
+        view
+        virtual
+        override
+        returns (int256, uint256, uint256)
+    {
+        (int256 answer, uint256 updatedAt) = _tryLatestRoundDataAt(timestamp, maxTraversal);
+        return (DecimalLib.convertDecimals(answer, SOURCE_DECIMALS, 18), updatedAt, 1);
+    }
+
+    /**
+     * @notice Initiate a snapshot of the source data. This is a no-op for Coinbase.
+     */
+    function snapshotData() public virtual override {}
+
+    /**
+     * @notice Returns the latest data from the source.
+     * @return answer The latest answer in 18 decimals.
+     * @return updatedAt The timestamp of the answer.
+     */
+    function getLatestSourceData() public view virtual override returns (int256, uint256) {
+        (, int256 sourceAnswer,, uint256 updatedAt,) = COINBASE_SOURCE.latestRoundData(TICKER);
+        return (DecimalLib.convertDecimals(sourceAnswer, SOURCE_DECIMALS, 18), updatedAt);
+    }
+
+    function getSourceDataAtRound(uint256 /* roundId */ ) public view virtual override returns (int256, uint256) {
+        return (0, 0);
+    }
+
+    // Tries getting the latest data as of the requested timestamp. If this is not possible,
+    // returns the earliest data available past the requested timestamp considering the maxTraversal limitations.
+    function _tryLatestRoundDataAt(uint256 timestamp, uint256 maxTraversal) internal view returns (int256, uint256) {
+        (uint80 roundId, int256 answer,, uint256 updatedAt,) = COINBASE_SOURCE.latestRoundData(TICKER);
+
+        // If the latest update is older than or equal to the requested timestamp, return the latest data.
+        if (updatedAt <= timestamp) {
+            return (answer, updatedAt);
+        }
+
+        // Attempt traversing historical round data backwards from roundId.
+        (int256 historicalAnswer, uint256 historicalUpdatedAt) = _searchRoundDataAt(timestamp, roundId, maxTraversal);
+
+        // Validate returned data. If it is uninitialized, fall back to returning the current latest round data.
+        if (historicalUpdatedAt > 0) {
+            return (historicalAnswer, historicalUpdatedAt);
+        }
+
+        return (answer, updatedAt);
+    }
+
+    // Searches for the latest historical data not newer than the requested timestamp.
+    // Returns newer data than requested if it exceeds traversal limits or holds uninitialized data that should be handled by the caller.
+    function _searchRoundDataAt(uint256 timestamp, uint80 latestRoundId, uint256 maxTraversal)
+        internal
+        view
+        returns (int256, uint256)
+    {
+        int256 answer;
+        uint256 updatedAt;
+        for (uint80 i = 1; i <= maxTraversal && latestRoundId >= i; i++) {
+            (, answer,, updatedAt,) = COINBASE_SOURCE.getRoundData(TICKER, latestRoundId - i);
+            if (updatedAt <= timestamp) {
+                return (answer, updatedAt);
+            }
+        }
+
+        return (answer, updatedAt); // Did not find requested round. Return earliest round or uninitialized data.
+    }
+}

src/interfaces/coinbase/IAggregatorV3SourceCoinbase.sol

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+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.17;
+
+interface IAggregatorV3SourceCoinbase {
+    function decimals() external view returns (uint8);
+
+    function latestRoundData(string memory ticker)
+        external
+        view
+        returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound);
+
+    function getRoundData(string memory ticker, uint80 _roundId)
+        external
+        view
+        returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound);
+}

src/oracles/CoinbaseOracle.sol

@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: BUSL-1.1
+pragma solidity 0.8.17;
+
+import {IAggregatorV3SourceCoinbase} from "../interfaces/coinbase/IAggregatorV3SourceCoinbase.sol";
+
+/**
+ * @title CoinbaseOracle
+ * @notice A smart contract that serves as an oracle for price data reported by a designated reporter.
+ */
+contract CoinbaseOracle is IAggregatorV3SourceCoinbase {
+    address immutable reporter;
+
+    uint8 public immutable decimals;
+
+    struct PriceData {
+        uint80 lastRoundId;
+        mapping(uint80 => int256) roundAnswers;
+        mapping(uint80 => uint256) roundTimestamps;
+    }
+
+    mapping(string => PriceData) private prices;
+
+    event PricePushed(string indexed ticker, uint80 indexed roundId, int256 price, uint256 timestamp);
+
+    /**
+     * @notice Constructor to initialize the CoinbaseOracle contract.
+     * @param _decimals The number of decimals in the reported price.
+     * @param _reporter The address of the reporter allowed to push price data.
+     */
+    constructor(uint8 _decimals, address _reporter) {
+        decimals = _decimals;
+        reporter = _reporter;
+    }
+
+    /**
+     * @notice Returns the latest round data for a given ticker.
+     * @param ticker The ticker symbol to retrieve the data for.
+     * @return roundId The ID of the latest round.
+     * @return answer The latest price.
+     * @return startedAt The timestamp when the round started.
+     * @return updatedAt The timestamp when the round was updated.
+     * @return answeredInRound The round ID in which the answer was computed.
+     */
+    function latestRoundData(string memory ticker)
+        external
+        view
+        returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound)
+    {
+        PriceData storage priceData = prices[ticker];
+        int256 latestAnswer = priceData.roundAnswers[priceData.lastRoundId];
+        uint256 latestTimestamp = priceData.roundTimestamps[priceData.lastRoundId];
+        return (priceData.lastRoundId, latestAnswer, latestTimestamp, latestTimestamp, priceData.lastRoundId);
+    }
+
+    /**
+     * @notice Returns the data for a specific round for a given ticker.
+     * @param ticker The ticker symbol to retrieve the data for.
+     * @param roundId The round ID to retrieve the data for.
+     * @return roundId The ID of the round.
+     * @return answer The price of the round.
+     * @return startedAt The timestamp when the round started.
+     * @return updatedAt The timestamp when the round was updated.
+     * @return answeredInRound The round ID in which the answer was computed.
+     */
+    function getRoundData(string memory ticker, uint80 roundId)
+        external
+        view
+        returns (uint80, int256, uint256, uint256, uint80)
+    {
+        PriceData storage priceData = prices[ticker];
+        int256 latestAnswer = priceData.roundAnswers[roundId];
+        uint256 latestTimestamp = priceData.roundTimestamps[roundId];
+        return (roundId, latestAnswer, latestTimestamp, latestTimestamp, roundId);
+    }
+
+    /**
+     * @notice Pushes a new price to the oracle for a given ticker.
+     * @param priceData The encoded price data.
+     * @param signature The signature to verify the authenticity of the data.
+     */
+    function pushPrice(bytes memory priceData, bytes memory signature) external {
+        (
+            string memory kind, // e.g. "price"
+            uint256 timestamp, // e.g. 1629350000
+            string memory ticker, // e.g. "BTC"
+            uint256 price // 6 decimals
+        ) = abi.decode(priceData, (string, uint256, string, uint256));
+
+        require(keccak256(abi.encodePacked(kind)) == keccak256(abi.encodePacked("price")), "Invalid kind.");
+
+        PriceData storage priceDataStruct = prices[ticker];
+        uint256 latestTimestamp = priceDataStruct.roundTimestamps[priceDataStruct.lastRoundId];
+
+        require(timestamp > latestTimestamp, "Invalid timestamp.");
+        require(recoverSigner(priceData, signature) == reporter, "Invalid signature.");
+        require(price < uint256(type(int256).max), "Price exceeds max value.");
+
+        priceDataStruct.lastRoundId++;
+        priceDataStruct.roundAnswers[priceDataStruct.lastRoundId] = int256(price);
+        priceDataStruct.roundTimestamps[priceDataStruct.lastRoundId] = timestamp;
+
+        emit PricePushed(ticker, priceDataStruct.lastRoundId, int256(price), timestamp);
+    }
+
+    /**
+     * @notice Internal function to recover the signer of a message.
+     * @param message The message that was signed.
+     * @param signature The signature to recover the signer from.
+     * @return The address of the signer.
+     */
+    function recoverSigner(bytes memory message, bytes memory signature) internal pure returns (address) {
+        (bytes32 r, bytes32 s, uint8 v) = abi.decode(signature, (bytes32, bytes32, uint8));
+        bytes32 hash = keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", keccak256(message)));
+        return ecrecover(hash, v, r, s);
+    }
+}

test/unit/CoinbaseOracle.sol

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+// SPDX-License-Identifier: BUSL-1.1
+pragma solidity 0.8.17;
+
+import {CommonTest} from "../Common.sol";
+import {BaseController} from "../../src/controllers/BaseController.sol";
+import {CoinbaseSourceAdapter} from "../../src/adapters/source-adapters/CoinbaseSourceAdapter.sol";
+import {DecimalLib} from "../../src/adapters/lib/DecimalLib.sol";
+import {IAggregatorV3SourceCoinbase} from "../../src/interfaces/coinbase/IAggregatorV3SourceCoinbase.sol";
+import {CoinbaseOracle} from "../../src/oracles/CoinbaseOracle.sol";
+
+contract CoinbaseSourceAdapterTest is CommonTest {
+    CoinbaseOracle coinbaseOracle;
+
+    address public reporter;
+    uint256 public reporterPk;
+    string public constant ethTicker = "ETH";
+    string public constant btcTicker = "BTC";
+
+    function setUp() public {
+        (address _reporter, uint256 _reporterPk) = makeAddrAndKey("reporter");
+        reporter = _reporter;
+        reporterPk = _reporterPk;
+        coinbaseOracle = new CoinbaseOracle(6, reporter);
+    }
+
+    function testPushPriceETH() public {
+        _testPushPrice(ethTicker, 10e6);
+    }
+
+    function testPushPriceBTC() public {
+        _testPushPrice(btcTicker, 20e6);
+    }
+
+    function testPushPriceBothTickers() public {
+        _testPushPrice(ethTicker, 10e6);
+        vm.warp(block.timestamp + 1);
+        _testPushPrice(btcTicker, 20e6);
+    }
+
+    function _testPushPrice(string memory ticker, uint256 price) internal {
+        string memory kind = "price";
+        uint256 timestamp = block.timestamp;
+
+        bytes memory encodedData = abi.encode(kind, timestamp, ticker, price);
+
+        bytes32 hash = keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", keccak256(encodedData)));
+
+        (uint8 v, bytes32 r, bytes32 s) = vm.sign(reporterPk, hash);
+
+        bytes memory signature = abi.encode(r, s, v);
+
+        coinbaseOracle.pushPrice(encodedData, signature);
+
+        (, int256 answer, uint256 updatedAt,,) = coinbaseOracle.latestRoundData(ticker);
+
+        assertEq(uint256(answer), price);
+        assertEq(updatedAt, timestamp);
+    }
+}