feat(pulse): add pulse contracts (#2090)

* add initial contracts

* refactor

* fix

* fix test

* fix test

* fix

* fix

* add more tests

* add test for getFee

* add testWithdraw

* add testSetAndWithdrawAssFeeManager

* add testMaxNumPrices

* add testSetProviderUri

* add more test

* add testExecuteCallbackWithFutureTimestamp

* update tests

* remove provider

* address comments

* address comments

* prevent requests 60 mins in the future that could exploit gas price difference

* fix test

* add priceIds to PriceUpdateRequested event

* add 50% overhead to gas for cross-contract calls

* feat: add test for executing callback with gas overhead

* feat: add docs for requestPriceUpdatesWithCallback and executeCallback functions to IPulse interface

* fix: use fixed-length array for priceIds in req

* add test

* address comments

Author: cctdaniel

.gitignore

@@ -23,3 +23,4 @@ __pycache__
 .direnv
 .next
 .turbo/
+.cursorrules

target_chains/ethereum/contracts/contracts/pulse/IPulse.sol

@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: Apache 2
+
+pragma solidity ^0.8.0;
+
+import "@pythnetwork/pyth-sdk-solidity/IPyth.sol";
+import "./PulseEvents.sol";
+import "./PulseState.sol";
+
+interface IPulseConsumer {
+    function pulseCallback(
+        uint64 sequenceNumber,
+        address updater,
+        PythStructs.PriceFeed[] memory priceFeeds
+    ) external;
+}
+
+interface IPulse is PulseEvents {
+    // Core functions
+    /**
+     * @notice Requests price updates with a callback
+     * @dev The msg.value must be equal to getFee(callbackGasLimit)
+     * @param callbackGasLimit The amount of gas allocated for the callback execution
+     * @param publishTime The minimum publish time for price updates, it should be less than or equal to block.timestamp + 60
+     * @param priceIds The price feed IDs to update. Maximum 10 price feeds per request.
+     *        Requests requiring more feeds should be split into multiple calls.
+     * @return sequenceNumber The sequence number assigned to this request
+     * @dev Security note: The 60-second future limit on publishTime prevents a DoS vector where
+     *      attackers could submit many low-fee requests for far-future updates when gas prices
+     *      are low, forcing executors to fulfill them later when gas prices might be much higher.
+     *      Since tx.gasprice is used to calculate fees, allowing far-future requests would make
+     *      the fee estimation unreliable.
+     */
+    function requestPriceUpdatesWithCallback(
+        uint256 publishTime,
+        bytes32[] calldata priceIds,
+        uint256 callbackGasLimit
+    ) external payable returns (uint64 sequenceNumber);
+
+    /**
+     * @notice Executes the callback for a price update request
+     * @dev Requires 1.5x the callback gas limit to account for cross-contract call overhead
+     * For example, if callbackGasLimit is 1M, the transaction needs at least 1.5M gas + some gas for some other operations in the function before the callback
+     * @param sequenceNumber The sequence number of the request
+     * @param updateData The raw price update data from Pyth
+     * @param priceIds The price feed IDs to update, must match the request
+     */
+    function executeCallback(
+        uint64 sequenceNumber,
+        bytes[] calldata updateData,
+        bytes32[] calldata priceIds
+    ) external payable;
+
+    // Getters
+    /**
+     * @notice Gets the base fee charged by Pyth protocol
+     * @dev This is a fixed fee per request that goes to the Pyth protocol, separate from gas costs
+     * @return pythFeeInWei The base fee in wei that every request must pay
+     */
+    function getPythFeeInWei() external view returns (uint128 pythFeeInWei);
+
+    /**
+     * @notice Calculates the total fee required for a price update request
+     * @dev Total fee = base Pyth protocol fee + gas costs for callback
+     * @param callbackGasLimit The amount of gas allocated for callback execution
+     * @return feeAmount The total fee in wei that must be provided as msg.value
+     */
+    function getFee(
+        uint256 callbackGasLimit
+    ) external view returns (uint128 feeAmount);
+
+    function getAccruedFees() external view returns (uint128 accruedFeesInWei);
+
+    function getRequest(
+        uint64 sequenceNumber
+    ) external view returns (PulseState.Request memory req);
+
+    // Add these functions to the IPulse interface
+    function setFeeManager(address manager) external;
+
+    function withdrawAsFeeManager(uint128 amount) external;
+}

target_chains/ethereum/contracts/contracts/pulse/Pulse.sol

@@ -0,0 +1,291 @@
+// SPDX-License-Identifier: Apache 2
+
+pragma solidity ^0.8.0;
+
+import "@openzeppelin/contracts/utils/math/SafeCast.sol";
+import "@pythnetwork/pyth-sdk-solidity/IPyth.sol";
+import "./IPulse.sol";
+import "./PulseState.sol";
+import "./PulseErrors.sol";
+
+abstract contract Pulse is IPulse, PulseState {
+    function _initialize(
+        address admin,
+        uint128 pythFeeInWei,
+        address pythAddress,
+        bool prefillRequestStorage
+    ) internal {
+        require(admin != address(0), "admin is zero address");
+        require(pythAddress != address(0), "pyth is zero address");
+
+        _state.admin = admin;
+        _state.accruedFeesInWei = 0;
+        _state.pythFeeInWei = pythFeeInWei;
+        _state.pyth = pythAddress;
+        _state.currentSequenceNumber = 1;
+
+        if (prefillRequestStorage) {
+            for (uint8 i = 0; i < NUM_REQUESTS; i++) {
+                Request storage req = _state.requests[i];
+                req.sequenceNumber = 0;
+                req.publishTime = 1;
+                req.callbackGasLimit = 1;
+                req.requester = address(1);
+                req.numPriceIds = 0;
+                // Pre-warm the priceIds array storage
+                for (uint8 j = 0; j < MAX_PRICE_IDS; j++) {
+                    req.priceIds[j] = bytes32(0);
+                }
+            }
+        }
+    }
+
+    function requestPriceUpdatesWithCallback(
+        uint256 publishTime,
+        bytes32[] calldata priceIds,
+        uint256 callbackGasLimit
+    ) external payable override returns (uint64 requestSequenceNumber) {
+        // NOTE: The 60-second future limit on publishTime prevents a DoS vector where
+        //      attackers could submit many low-fee requests for far-future updates when gas prices
+        //      are low, forcing executors to fulfill them later when gas prices might be much higher.
+        //      Since tx.gasprice is used to calculate fees, allowing far-future requests would make
+        //      the fee estimation unreliable.
+        require(publishTime <= block.timestamp + 60, "Too far in future");
+        if (priceIds.length > MAX_PRICE_IDS) {
+            revert TooManyPriceIds(priceIds.length, MAX_PRICE_IDS);
+        }
+        requestSequenceNumber = _state.currentSequenceNumber++;
+
+        uint128 requiredFee = getFee(callbackGasLimit);
+        if (msg.value < requiredFee) revert InsufficientFee();
+
+        Request storage req = allocRequest(requestSequenceNumber);
+        req.sequenceNumber = requestSequenceNumber;
+        req.publishTime = publishTime;
+        req.callbackGasLimit = callbackGasLimit;
+        req.requester = msg.sender;
+        req.numPriceIds = uint8(priceIds.length);
+
+        // Copy price IDs to storage
+        for (uint8 i = 0; i < priceIds.length; i++) {
+            req.priceIds[i] = priceIds[i];
+        }
+
+        _state.accruedFeesInWei += SafeCast.toUint128(msg.value);
+
+        emit PriceUpdateRequested(req, priceIds);
+    }
+
+    function executeCallback(
+        uint64 sequenceNumber,
+        bytes[] calldata updateData,
+        bytes32[] calldata priceIds
+    ) external payable override {
+        Request storage req = findActiveRequest(sequenceNumber);
+
+        // Verify priceIds match
+        require(
+            priceIds.length == req.numPriceIds,
+            "Price IDs length mismatch"
+        );
+        for (uint8 i = 0; i < req.numPriceIds; i++) {
+            if (priceIds[i] != req.priceIds[i]) {
+                revert InvalidPriceIds(priceIds[i], req.priceIds[i]);
+            }
+        }
+
+        // Parse price feeds first to measure gas usage
+        PythStructs.PriceFeed[] memory priceFeeds = IPyth(_state.pyth)
+            .parsePriceFeedUpdates(
+                updateData,
+                priceIds,
+                SafeCast.toUint64(req.publishTime),
+                SafeCast.toUint64(req.publishTime)
+            );
+
+        clearRequest(sequenceNumber);
+
+        // Check if enough gas remains for callback + events/cleanup
+        // We need extra gas beyond callbackGasLimit for:
+        // 1. Emitting success/failure events
+        // 2. Error handling in catch blocks
+        // 3. State cleanup operations
+        if (gasleft() < (req.callbackGasLimit * 3) / 2) {
+            revert InsufficientGas();
+        }
+
+        try
+            IPulseConsumer(req.requester).pulseCallback{
+                gas: req.callbackGasLimit
+            }(sequenceNumber, msg.sender, priceFeeds)
+        {
+            // Callback succeeded
+            emitPriceUpdate(sequenceNumber, priceIds, priceFeeds);
+        } catch Error(string memory reason) {
+            // Explicit revert/require
+            emit PriceUpdateCallbackFailed(
+                sequenceNumber,
+                msg.sender,
+                priceIds,
+                req.requester,
+                reason
+            );
+        } catch {
+            // Out of gas or other low-level errors
+            emit PriceUpdateCallbackFailed(
+                sequenceNumber,
+                msg.sender,
+                priceIds,
+                req.requester,
+                "low-level error (possibly out of gas)"
+            );
+        }
+    }
+
+    function emitPriceUpdate(
+        uint64 sequenceNumber,
+        bytes32[] memory priceIds,
+        PythStructs.PriceFeed[] memory priceFeeds
+    ) internal {
+        int64[] memory prices = new int64[](priceFeeds.length);
+        uint64[] memory conf = new uint64[](priceFeeds.length);
+        int32[] memory expos = new int32[](priceFeeds.length);
+        uint256[] memory publishTimes = new uint256[](priceFeeds.length);
+
+        for (uint i = 0; i < priceFeeds.length; i++) {
+            prices[i] = priceFeeds[i].price.price;
+            conf[i] = priceFeeds[i].price.conf;
+            expos[i] = priceFeeds[i].price.expo;
+            publishTimes[i] = priceFeeds[i].price.publishTime;
+        }
+
+        emit PriceUpdateExecuted(
+            sequenceNumber,
+            msg.sender,
+            priceIds,
+            prices,
+            conf,
+            expos,
+            publishTimes
+        );
+    }
+
+    function getFee(
+        uint256 callbackGasLimit
+    ) public view override returns (uint128 feeAmount) {
+        uint128 baseFee = _state.pythFeeInWei;
+        uint256 gasFee = callbackGasLimit * tx.gasprice;
+        feeAmount = baseFee + SafeCast.toUint128(gasFee);
+    }
+
+    function getPythFeeInWei()
+        public
+        view
+        override
+        returns (uint128 pythFeeInWei)
+    {
+        pythFeeInWei = _state.pythFeeInWei;
+    }
+
+    function getAccruedFees()
+        public
+        view
+        override
+        returns (uint128 accruedFeesInWei)
+    {
+        accruedFeesInWei = _state.accruedFeesInWei;
+    }
+
+    function getRequest(
+        uint64 sequenceNumber
+    ) public view override returns (Request memory req) {
+        req = findRequest(sequenceNumber);
+    }
+
+    function requestKey(
+        uint64 sequenceNumber
+    ) internal pure returns (bytes32 hash, uint8 shortHash) {
+        hash = keccak256(abi.encodePacked(sequenceNumber));
+        shortHash = uint8(hash[0] & NUM_REQUESTS_MASK);
+    }
+
+    function withdrawFees(uint128 amount) external {
+        require(msg.sender == _state.admin, "Only admin can withdraw fees");
+        require(_state.accruedFeesInWei >= amount, "Insufficient balance");
+
+        _state.accruedFeesInWei -= amount;
+
+        (bool sent, ) = msg.sender.call{value: amount}("");
+        require(sent, "Failed to send fees");
+
+        emit FeesWithdrawn(msg.sender, amount);
+    }
+
+    function findActiveRequest(
+        uint64 sequenceNumber
+    ) internal view returns (Request storage req) {
+        req = findRequest(sequenceNumber);
+
+        if (!isActive(req) || req.sequenceNumber != sequenceNumber)
+            revert NoSuchRequest();
+    }
+
+    function findRequest(
+        uint64 sequenceNumber
+    ) internal view returns (Request storage req) {
+        (bytes32 key, uint8 shortKey) = requestKey(sequenceNumber);
+
+        req = _state.requests[shortKey];
+        if (req.sequenceNumber == sequenceNumber) {
+            return req;
+        } else {
+            req = _state.requestsOverflow[key];
+        }
+    }
+
+    function clearRequest(uint64 sequenceNumber) internal {
+        (bytes32 key, uint8 shortKey) = requestKey(sequenceNumber);
+
+        Request storage req = _state.requests[shortKey];
+        if (req.sequenceNumber == sequenceNumber) {
+            req.sequenceNumber = 0;
+        } else {
+            delete _state.requestsOverflow[key];
+        }
+    }
+
+    function allocRequest(
+        uint64 sequenceNumber
+    ) internal returns (Request storage req) {
+        (, uint8 shortKey) = requestKey(sequenceNumber);
+
+        req = _state.requests[shortKey];
+        if (isActive(req)) {
+            (bytes32 reqKey, ) = requestKey(req.sequenceNumber);
+            _state.requestsOverflow[reqKey] = req;
+        }
+    }
+
+    function isActive(Request storage req) internal view returns (bool) {
+        return req.sequenceNumber != 0;
+    }
+
+    function setFeeManager(address manager) external override {
+        require(msg.sender == _state.admin, "Only admin can set fee manager");
+        address oldFeeManager = _state.feeManager;
+        _state.feeManager = manager;
+        emit FeeManagerUpdated(_state.admin, oldFeeManager, manager);
+    }
+
+    function withdrawAsFeeManager(uint128 amount) external override {
+        require(msg.sender == _state.feeManager, "Only fee manager");
+        require(_state.accruedFeesInWei >= amount, "Insufficient balance");
+
+        _state.accruedFeesInWei -= amount;
+
+        (bool sent, ) = msg.sender.call{value: amount}("");
+        require(sent, "Failed to send fees");
+
+        emit FeesWithdrawn(msg.sender, amount);
+    }
+}

target_chains/ethereum/contracts/contracts/pulse/PulseErrors.sol

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: Apache 2
+
+pragma solidity ^0.8.0;
+
+error NoSuchProvider();
+error NoSuchRequest();
+error InsufficientFee();
+error Unauthorized();
+error InvalidCallbackGas();
+error CallbackFailed();
+error InvalidPriceIds(bytes32 providedPriceIdsHash, bytes32 storedPriceIdsHash);
+error InvalidCallbackGasLimit(uint256 requested, uint256 stored);
+error ExceedsMaxPrices(uint32 requested, uint32 maxAllowed);
+error InsufficientGas();
+error TooManyPriceIds(uint256 provided, uint256 maximum);