SIP-165 Debt Orcale

contracts/BaseSingleNetworkAggregator.sol

@@ -0,0 +1,69 @@
+pragma solidity ^0.5.16;
+
+//import "@chainlink/contracts-0.0.10/src/v0.5/interfaces/AggregatorV2V3Interface.sol";
+
+import "./AddressResolver.sol";
+import "./interfaces/IDebtCache.sol";
+import "./interfaces/ISynthetixDebtShare.sol";
+import "./interfaces/AggregatorV2V3Interface.sol";
+
+import "./SafeDecimalMath.sol";
+
+// aggregator which reports the data from the system itself
+// useful for testing
+contract BaseSingleNetworkAggregator is Owned, AggregatorV2V3Interface {
+    using SafeDecimalMath for uint;
+
+    AddressResolver public resolver;
+
+    uint public overrideTimestamp;
+
+    constructor(AddressResolver _resolver) public Owned(msg.sender) {
+        resolver = _resolver;
+    }
+
+    function setOverrideTimestamp(uint timestamp) public onlyOwner {
+        overrideTimestamp = timestamp;
+    }
+
+    function latestRoundData()
+        external
+        view
+        returns (
+            uint80,
+            int256,
+            uint256,
+            uint256,
+            uint80
+        )
+    {
+        return getRoundData(uint80(latestRound()));
+    }
+
+    function latestRound() public view returns (uint256) {
+        return 1;
+    }
+
+    function decimals() external view returns (uint8) {
+        return 0;
+    }
+
+    function getAnswer(uint256 _roundId) external view returns (int256 answer) {
+        (,answer,,,) = getRoundData(uint80(_roundId));
+    }
+
+    function getTimestamp(uint256 _roundId) external view returns (uint256 timestamp) {
+        (,,timestamp,,) = getRoundData(uint80(_roundId));
+    }
+
+    function getRoundData(uint80)
+        public
+        view
+        returns (
+            uint80,
+            int256,
+            uint256,
+            uint256,
+            uint80
+        );
+}

contracts/BaseSynthetixBridge.sol

@@ -10,13 +10,15 @@ import "./interfaces/IBaseSynthetixBridge.sol";
 // Internal references
 import "./interfaces/ISynthetix.sol";
 import "./interfaces/IRewardEscrowV2.sol";
+import "./interfaces/IFeePool.sol";
 import "@eth-optimism/contracts/iOVM/bridge/messaging/iAbs_BaseCrossDomainMessenger.sol";
 
 contract BaseSynthetixBridge is Owned, MixinSystemSettings, IBaseSynthetixBridge {
     /* ========== ADDRESS RESOLVER CONFIGURATION ========== */
     bytes32 private constant CONTRACT_EXT_MESSENGER = "ext:Messenger";
     bytes32 internal constant CONTRACT_SYNTHETIX = "Synthetix";
     bytes32 private constant CONTRACT_REWARDESCROW = "RewardEscrowV2";
+    bytes32 private constant CONTRACT_FEEPOOL = "FeePool";
 
     bool public initiationActive;
 
@@ -40,6 +42,10 @@ contract BaseSynthetixBridge is Owned, MixinSystemSettings, IBaseSynthetixBridge
         return IRewardEscrowV2(requireAndGetAddress(CONTRACT_REWARDESCROW));
     }
 
+    function feePool() internal view returns (IFeePool) {
+        return IFeePool(requireAndGetAddress(CONTRACT_FEEPOOL));
+    }
+
     function initiatingActive() internal view {
         require(initiationActive, "Initiation deactivated");
     }
@@ -48,10 +54,11 @@ contract BaseSynthetixBridge is Owned, MixinSystemSettings, IBaseSynthetixBridge
 
     function resolverAddressesRequired() public view returns (bytes32[] memory addresses) {
         bytes32[] memory existingAddresses = MixinSystemSettings.resolverAddressesRequired();
-        bytes32[] memory newAddresses = new bytes32[](3);
+        bytes32[] memory newAddresses = new bytes32[](4);
         newAddresses[0] = CONTRACT_EXT_MESSENGER;
         newAddresses[1] = CONTRACT_SYNTHETIX;
         newAddresses[2] = CONTRACT_REWARDESCROW;
+        newAddresses[3] = CONTRACT_FEEPOOL;
         addresses = combineArrays(existingAddresses, newAddresses);
     }
 

contracts/FeePool.sol

@@ -11,6 +11,8 @@ import "./interfaces/IFeePool.sol";
 // Libraries
 import "./SafeDecimalMath.sol";
 
+import "@chainlink/contracts-0.0.10/src/v0.5/interfaces/AggregatorV2V3Interface.sol";
+
 // Internal references
 import "./interfaces/IERC20.sol";
 import "./interfaces/ISynth.sol";
@@ -26,6 +28,7 @@ import "./interfaces/IRewardsDistribution.sol";
 import "./interfaces/ICollateralManager.sol";
 import "./interfaces/IEtherWrapper.sol";
 import "./interfaces/IWrapperFactory.sol";
+import "./interfaces/ISynthetixBridgeToOptimism.sol";
 
 // https://docs.synthetix.io/contracts/source/contracts/feepool
 contract FeePool is Owned, Proxyable, LimitedSetup, MixinSystemSettings, IFeePool {
@@ -44,6 +47,10 @@ contract FeePool is Owned, Proxyable, LimitedSetup, MixinSystemSettings, IFeePoo
     struct FeePeriod {
         uint64 feePeriodId;
         uint64 startTime;
+
+        uint allNetworksSnxBackedDebt;
+        uint allNetworksDebtSharesSupply;
+
         uint feesToDistribute;
         uint feesClaimed;
         uint rewardsToDistribute;
@@ -74,6 +81,12 @@ contract FeePool is Owned, Proxyable, LimitedSetup, MixinSystemSettings, IFeePoo
     bytes32 private constant CONTRACT_ETHER_WRAPPER = "EtherWrapper";
     bytes32 private constant CONTRACT_WRAPPER_FACTORY = "WrapperFactory";
 
+    bytes32 private constant CONTRACT_SYNTHETIX_BRIDGE_TO_OPTIMISM = "SynthetixBridgeToOptimism";
+    bytes32 private constant CONTRACT_SYNTHETIX_BRIDGE_TO_BASE = "SynthetixBridgeToBase";
+
+    bytes32 private constant CONTRACT_EXT_AGGREGATOR_ISSUED_SYNTHS = "ext:AggregatorIssuedSynths";
+    bytes32 private constant CONTRACT_EXT_AGGREGATOR_DEBT_RATIO = "ext:AggregatorDebtRatio";
+
     /* ========== ETERNAL STORAGE CONSTANTS ========== */
 
     bytes32 private constant LAST_FEE_WITHDRAWAL = "last_fee_withdrawal";
@@ -91,7 +104,7 @@ contract FeePool is Owned, Proxyable, LimitedSetup, MixinSystemSettings, IFeePoo
     /* ========== VIEWS ========== */
     function resolverAddressesRequired() public view returns (bytes32[] memory addresses) {
         bytes32[] memory existingAddresses = MixinSystemSettings.resolverAddressesRequired();
-        bytes32[] memory newAddresses = new bytes32[](11);
+        bytes32[] memory newAddresses = new bytes32[](13);
         newAddresses[0] = CONTRACT_SYSTEMSTATUS;
         newAddresses[1] = CONTRACT_SYNTHETIXDEBTSHARE;
         newAddresses[2] = CONTRACT_FEEPOOLETERNALSTORAGE;
@@ -103,6 +116,8 @@ contract FeePool is Owned, Proxyable, LimitedSetup, MixinSystemSettings, IFeePoo
         newAddresses[8] = CONTRACT_COLLATERALMANAGER;
         newAddresses[9] = CONTRACT_WRAPPER_FACTORY;
         newAddresses[10] = CONTRACT_ETHER_WRAPPER;
+        newAddresses[11] = CONTRACT_EXT_AGGREGATOR_ISSUED_SYNTHS;
+        newAddresses[12] = CONTRACT_EXT_AGGREGATOR_DEBT_RATIO;
         addresses = combineArrays(existingAddresses, newAddresses);
     }
 
@@ -162,6 +177,26 @@ contract FeePool is Owned, Proxyable, LimitedSetup, MixinSystemSettings, IFeePoo
         return getTargetThreshold();
     }
 
+    function allNetworksSnxBackedDebt() internal view returns (uint256 debt, uint256 updatedAt) {
+        (, int256 rawData, , uint timestamp, ) = AggregatorV2V3Interface(requireAndGetAddress(CONTRACT_EXT_AGGREGATOR_ISSUED_SYNTHS))
+            .latestRoundData();
+
+        debt = uint(rawData);
+        updatedAt = timestamp;
+    }
+
+    function allNetworksDebtSharesSupply() internal view returns (uint256 sharesSupply, uint256 updatedAt) {
+        (, int256 rawIssuedSynths, , uint issuedSynthsUpdatedAt, ) = AggregatorV2V3Interface(requireAndGetAddress(CONTRACT_EXT_AGGREGATOR_ISSUED_SYNTHS))
+            .latestRoundData();
+
+        (, int256 rawRatio, , uint ratioUpdatedAt, ) = AggregatorV2V3Interface(requireAndGetAddress(CONTRACT_EXT_AGGREGATOR_DEBT_RATIO))
+            .latestRoundData();
+
+        uint debt = uint(rawIssuedSynths);
+        sharesSupply = rawRatio == 0 ? 0 : debt.divideDecimalRoundPrecise(uint(rawRatio));
+        updatedAt = issuedSynthsUpdatedAt < ratioUpdatedAt ? issuedSynthsUpdatedAt : ratioUpdatedAt;
+    }
+
     function recentFeePeriods(uint index)
         external
         view
@@ -216,9 +251,32 @@ contract FeePool is Owned, Proxyable, LimitedSetup, MixinSystemSettings, IFeePoo
         require(getFeePeriodDuration() > 0, "Fee Period Duration not set");
         require(_recentFeePeriodsStorage(0).startTime <= (now - getFeePeriodDuration()), "Too early to close fee period");
 
+        // get current oracle values
+        (uint snxBackedDebt, ) = allNetworksSnxBackedDebt();
+        (uint debtSharesSupply, ) = allNetworksDebtSharesSupply();
+
+        // close on this chain
+        _closeSecondary(snxBackedDebt, debtSharesSupply);
+
+        // inform other chain of the chosen values
+        ISynthetixBridgeToOptimism(resolver.requireAndGetAddress(CONTRACT_SYNTHETIX_BRIDGE_TO_OPTIMISM, "Missing contract: SynthetixBridgeToOptimism")).closeFeePeriod(snxBackedDebt, debtSharesSupply);
+    }
+
+    function closeSecondary(uint allNetworksSnxBackedDebt, uint allNetworksDebtSharesSupply) external onlyRelayer {
+        _closeSecondary(allNetworksSnxBackedDebt, allNetworksDebtSharesSupply);
+    }
+
+    /**
+     * @notice Close the current fee period and start a new one.
+     */
+    function _closeSecondary(uint allNetworksSnxBackedDebt, uint allNetworksDebtSharesSupply) internal {
         etherWrapper().distributeFees();
         wrapperFactory().distributeFees();
 
+        // before closing the current fee period, set the recorded snxBackedDebt and debtSharesSupply
+        _recentFeePeriodsStorage(0).allNetworksDebtSharesSupply = allNetworksDebtSharesSupply;
+        _recentFeePeriodsStorage(0).allNetworksSnxBackedDebt = allNetworksSnxBackedDebt;
+
         // Note:  when FEE_PERIOD_LENGTH = 2, periodClosing is the current period & periodToRollover is the last open claimable period
         FeePeriod storage periodClosing = _recentFeePeriodsStorage(FEE_PERIOD_LENGTH - 2);
         FeePeriod storage periodToRollover = _recentFeePeriodsStorage(FEE_PERIOD_LENGTH - 1);
@@ -340,7 +398,9 @@ contract FeePool is Owned, Proxyable, LimitedSetup, MixinSystemSettings, IFeePoo
             feesToDistribute: feesToDistribute,
             feesClaimed: feesClaimed,
             rewardsToDistribute: rewardsToDistribute,
-            rewardsClaimed: rewardsClaimed
+            rewardsClaimed: rewardsClaimed,
+            allNetworksSnxBackedDebt: 0,
+            allNetworksDebtSharesSupply: 0
         });
 
         // make sure recording is aware of the actual period id
@@ -645,6 +705,20 @@ contract FeePool is Owned, Proxyable, LimitedSetup, MixinSystemSettings, IFeePoo
         _;
     }
 
+    modifier onlyIssuer {
+        bool isIssuer = msg.sender == address(issuer());
+        require(isIssuer, "Issuer only");
+        _;
+    }
+
+    modifier onlyRelayer {
+        require(
+            msg.sender == address(this) ||
+            msg.sender == resolver.getAddress(CONTRACT_SYNTHETIX_BRIDGE_TO_BASE)
+        , "Only valid relayer can call");
+        _;
+    }
+
     modifier notFeeAddress(address account) {
         require(account != FEE_ADDRESS, "Fee address not allowed");
         _;

contracts/Issuer.sol

@@ -21,11 +21,12 @@ import "./interfaces/IExchangeRates.sol";
 import "./interfaces/IHasBalance.sol";
 import "./interfaces/IERC20.sol";
 import "./interfaces/ILiquidations.sol";
-import "./interfaces/ICollateralManager.sol";
 import "./interfaces/IRewardEscrowV2.sol";
 import "./interfaces/ISynthRedeemer.sol";
 import "./Proxyable.sol";
 
+import "@chainlink/contracts-0.0.10/src/v0.5/interfaces/AggregatorV2V3Interface.sol";
+
 interface IProxy {
     function target() external view returns (address);
 }
@@ -88,12 +89,15 @@ contract Issuer is Owned, MixinSystemSettings, IIssuer {
     bytes32 private constant CONTRACT_DEBTCACHE = "DebtCache";
     bytes32 private constant CONTRACT_SYNTHREDEEMER = "SynthRedeemer";
 
+    bytes32 private constant CONTRACT_EXT_AGGREGATOR_ISSUED_SYNTHS = "ext:AggregatorIssuedSynths";
+    bytes32 private constant CONTRACT_EXT_AGGREGATOR_DEBT_RATIO = "ext:AggregatorDebtRatio";
+
     constructor(address _owner, address _resolver) public Owned(_owner) MixinSystemSettings(_resolver) {}
 
     /* ========== VIEWS ========== */
     function resolverAddressesRequired() public view returns (bytes32[] memory addresses) {
         bytes32[] memory existingAddresses = MixinSystemSettings.resolverAddressesRequired();
-        bytes32[] memory newAddresses = new bytes32[](11);
+        bytes32[] memory newAddresses = new bytes32[](13);
         newAddresses[0] = CONTRACT_SYNTHETIX;
         newAddresses[1] = CONTRACT_EXCHANGER;
         newAddresses[2] = CONTRACT_EXRATES;
@@ -105,6 +109,8 @@ contract Issuer is Owned, MixinSystemSettings, IIssuer {
         newAddresses[8] = CONTRACT_LIQUIDATIONS;
         newAddresses[9] = CONTRACT_DEBTCACHE;
         newAddresses[10] = CONTRACT_SYNTHREDEEMER;
+        newAddresses[11] = CONTRACT_EXT_AGGREGATOR_ISSUED_SYNTHS;
+        newAddresses[12] = CONTRACT_EXT_AGGREGATOR_DEBT_RATIO;
         return combineArrays(existingAddresses, newAddresses);
     }
 
@@ -152,6 +158,20 @@ contract Issuer is Owned, MixinSystemSettings, IIssuer {
         return ISynthRedeemer(requireAndGetAddress(CONTRACT_SYNTHREDEEMER));
     }
 
+    function allNetworksDebtInfo() public view returns (uint256 debt, uint256 sharesSupply, bool isStale) {
+
+        (, int256 rawIssuedSynths, , uint issuedSynthsUpdatedAt, ) = AggregatorV2V3Interface(requireAndGetAddress(CONTRACT_EXT_AGGREGATOR_ISSUED_SYNTHS))
+            .latestRoundData();
+
+        (, int256 rawRatio, , uint ratioUpdatedAt, ) = AggregatorV2V3Interface(requireAndGetAddress(CONTRACT_EXT_AGGREGATOR_DEBT_RATIO))
+            .latestRoundData();
+
+        debt = uint(rawIssuedSynths);
+        sharesSupply = rawRatio == 0 ? 0 : debt.divideDecimalRoundPrecise(uint(rawRatio));
+        isStale = block.timestamp - getRateStalePeriod() > issuedSynthsUpdatedAt ||
+                block.timestamp - getRateStalePeriod() > ratioUpdatedAt;
+    }
+
     function issuanceRatio() external view returns (uint) {
         return getIssuanceRatio();
     }
@@ -216,14 +236,19 @@ contract Issuer is Owned, MixinSystemSettings, IIssuer {
     {
 
         // What's the total value of the system excluding ETH backed synths in their requested currency?
-        (totalSystemValue, anyRateIsInvalid) = _totalIssuedSynths(currencyKey, true);
+        (uint snxBackedAmount, uint debtSharesAmount, bool debtInfoStale) = allNetworksDebtInfo();
 
-        // If it's zero, they haven't issued, and they have no debt.
-        // Note: it's more gas intensive to put this check here rather than before _totalIssuedSynths
-        // if they have 0 SNX, but it's a necessary trade-off
-        if (debtShareBalance == 0) return (0, totalSystemValue, anyRateIsInvalid);
+        if (debtShareBalance == 0) {
+            return (0, snxBackedAmount, debtInfoStale);
+        }
+
+        // existing functionality requires for us to convert into the exchange rate specified by `currencyKey`
+        (uint currencyRate, bool currencyRateInvalid) = exchangeRates().rateAndInvalid(currencyKey);
+
+        debtBalance = _debtSharesToIssuedSynth(debtShareBalance, snxBackedAmount, debtSharesAmount).divideDecimalRound(currencyRate);
+        totalSystemValue = snxBackedAmount;
 
-        debtBalance = _debtSharesToIssuedSynth(debtShareBalance, totalSystemValue, synthetixDebtShare().totalSupply());
+        anyRateIsInvalid = currencyRateInvalid || debtInfoStale;
     }
 
     function _canBurnSynths(address account) internal view returns (bool) {

contracts/MixinSystemSettings.sol

@@ -34,6 +34,7 @@ contract MixinSystemSettings is MixinResolver {
     bytes32 internal constant SETTING_CROSS_DOMAIN_ESCROW_GAS_LIMIT = "crossDomainEscrowGasLimit";
     bytes32 internal constant SETTING_CROSS_DOMAIN_REWARD_GAS_LIMIT = "crossDomainRewardGasLimit";
     bytes32 internal constant SETTING_CROSS_DOMAIN_WITHDRAWAL_GAS_LIMIT = "crossDomainWithdrawalGasLimit";
+    bytes32 internal constant SETTING_CROSS_DOMAIN_FEE_PERIOD_CLOSE_GAS_LIMIT = "crossDomainCloseGasLimit";
     bytes32 internal constant SETTING_CROSS_DOMAIN_RELAY_GAS_LIMIT = "crossDomainRelayGasLimit";
     bytes32 internal constant SETTING_ETHER_WRAPPER_MAX_ETH = "etherWrapperMaxETH";
     bytes32 internal constant SETTING_ETHER_WRAPPER_MINT_FEE_RATE = "etherWrapperMintFeeRate";
@@ -53,7 +54,7 @@ contract MixinSystemSettings is MixinResolver {
 
     bytes32 internal constant CONTRACT_FLEXIBLESTORAGE = "FlexibleStorage";
 
-    enum CrossDomainMessageGasLimits {Deposit, Escrow, Reward, Withdrawal, Relay}
+    enum CrossDomainMessageGasLimits {Deposit, Escrow, Reward, Withdrawal, CloseFeePeriod, Relay}
 
     struct DynamicFeeConfig {
         uint threshold;
@@ -84,6 +85,8 @@ contract MixinSystemSettings is MixinResolver {
             return SETTING_CROSS_DOMAIN_WITHDRAWAL_GAS_LIMIT;
         } else if (gasLimitType == CrossDomainMessageGasLimits.Relay) {
             return SETTING_CROSS_DOMAIN_RELAY_GAS_LIMIT;
+        } else if (gasLimitType == CrossDomainMessageGasLimits.CloseFeePeriod) {
+            return SETTING_CROSS_DOMAIN_FEE_PERIOD_CLOSE_GAS_LIMIT;
         } else {
             revert("Unknown gas limit type");
         }