feat: add Rewards Eligibility Oracle (REO)

Author: RembrandtK

packages/contracts/contracts/rewards/RewardsManager.sol

@@ -7,15 +7,17 @@ pragma abicoder v2;
 // solhint-disable gas-increment-by-one, gas-indexed-events, gas-small-strings, gas-strict-inequalities
 
 import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";
+import { IERC165 } from "@openzeppelin/contracts/introspection/IERC165.sol";
 
 import { GraphUpgradeable } from "../upgrades/GraphUpgradeable.sol";
 import { Managed } from "../governance/Managed.sol";
 import { MathUtils } from "../staking/libs/MathUtils.sol";
 import { IGraphToken } from "../token/IGraphToken.sol";
 
-import { RewardsManagerV5Storage } from "./RewardsManagerStorage.sol";
+import { RewardsManagerV6Storage } from "./RewardsManagerStorage.sol";
 import { IRewardsManager } from "@graphprotocol/interfaces/contracts/contracts/rewards/IRewardsManager.sol";
 import { IRewardsIssuer } from "./IRewardsIssuer.sol";
+import { IRewardsEligibilityOracle } from "@graphprotocol/interfaces/contracts/issuance/eligibility/IRewardsEligibilityOracle.sol";
 
 /**
  * @title Rewards Manager Contract
@@ -37,7 +39,7 @@ import { IRewardsIssuer } from "./IRewardsIssuer.sol";
  * until the actual takeRewards function is called.
  * custom:security-contact Please email security+contracts@ thegraph.com (remove space) if you find any bugs. We might have an active bug bounty program.
  */
-contract RewardsManager is RewardsManagerV5Storage, GraphUpgradeable, IRewardsManager {
+contract RewardsManager is RewardsManagerV6Storage, GraphUpgradeable, IRewardsManager {
     using SafeMath for uint256;
 
     /// @dev Fixed point scaling factor used for decimals in reward calculations
@@ -61,6 +63,14 @@ contract RewardsManager is RewardsManagerV5Storage, GraphUpgradeable, IRewardsMa
      */
     event RewardsDenied(address indexed indexer, address indexed allocationID);
 
+    /**
+     * @notice Emitted when rewards are denied to an indexer due to eligibility
+     * @param indexer Address of the indexer being denied rewards
+     * @param allocationID Address of the allocation being denied rewards
+     * @param amount Amount of rewards that would have been assigned
+     */
+    event RewardsDeniedDueToEligibility(address indexed indexer, address indexed allocationID, uint256 amount);
+
     /**
      * @notice Emitted when a subgraph is denied for claiming rewards
      * @param subgraphDeploymentID Subgraph deployment ID being denied
@@ -75,6 +85,16 @@ contract RewardsManager is RewardsManagerV5Storage, GraphUpgradeable, IRewardsMa
      */
     event SubgraphServiceSet(address indexed oldSubgraphService, address indexed newSubgraphService);
 
+    /**
+     * @notice Emitted when the rewards eligibility oracle contract is set
+     * @param oldRewardsEligibilityOracle Previous rewards eligibility oracle address
+     * @param newRewardsEligibilityOracle New rewards eligibility oracle address
+     */
+    event RewardsEligibilityOracleSet(
+        address indexed oldRewardsEligibilityOracle,
+        address indexed newRewardsEligibilityOracle
+    );
+
     // -- Modifiers --
 
     /**
@@ -151,6 +171,28 @@ contract RewardsManager is RewardsManagerV5Storage, GraphUpgradeable, IRewardsMa
         emit SubgraphServiceSet(oldSubgraphService, _subgraphService);
     }
 
+    /**
+     * @inheritdoc IRewardsManager
+     * @dev Note that the rewards eligibility oracle can be set to the zero address to disable use of an oracle, in
+     * which case no indexers will be denied rewards due to eligibility.
+     */
+    function setRewardsEligibilityOracle(address newRewardsEligibilityOracle) external override onlyGovernor {
+        if (address(rewardsEligibilityOracle) != newRewardsEligibilityOracle) {
+            // Check that the contract supports the IRewardsEligibilityOracle interface
+            // Allow zero address to disable the oracle
+            if (newRewardsEligibilityOracle != address(0)) {
+                require(
+                    IERC165(newRewardsEligibilityOracle).supportsInterface(type(IRewardsEligibilityOracle).interfaceId),
+                    "Contract does not support IRewardsEligibilityOracle interface"
+                );
+            }
+
+            address oldRewardsEligibilityOracle = address(rewardsEligibilityOracle);
+            rewardsEligibilityOracle = IRewardsEligibilityOracle(newRewardsEligibilityOracle);
+            emit RewardsEligibilityOracleSet(oldRewardsEligibilityOracle, newRewardsEligibilityOracle);
+        }
+    }
+
     // -- Denylist --
 
     /**
@@ -404,6 +446,13 @@ contract RewardsManager is RewardsManagerV5Storage, GraphUpgradeable, IRewardsMa
             rewards = accRewardsPending.add(
                 _calcRewards(tokens, accRewardsPerAllocatedToken, updatedAccRewardsPerAllocatedToken)
             );
+
+            // Do not reward if indexer is not eligible based on rewards eligibility
+            if (address(rewardsEligibilityOracle) != address(0) && !rewardsEligibilityOracle.isEligible(indexer)) {
+                emit RewardsDeniedDueToEligibility(indexer, _allocationID, rewards);
+                return 0;
+            }
+
             if (rewards > 0) {
                 // Mint directly to rewards issuer for the reward amount
                 // The rewards issuer contract will do bookkeeping of the reward and

packages/contracts/contracts/rewards/RewardsManagerStorage.sol

@@ -7,6 +7,7 @@
 
 pragma solidity ^0.7.6 || 0.8.27;
 
+import { IRewardsEligibilityOracle } from "@graphprotocol/interfaces/contracts/issuance/eligibility/IRewardsEligibilityOracle.sol";
 import { IRewardsIssuer } from "./IRewardsIssuer.sol";
 import { IRewardsManager } from "@graphprotocol/interfaces/contracts/contracts/rewards/IRewardsManager.sol";
 import { Managed } from "../governance/Managed.sol";
@@ -75,3 +76,13 @@ contract RewardsManagerV5Storage is RewardsManagerV4Storage {
     /// @notice Address of the subgraph service
     IRewardsIssuer public subgraphService;
 }
+
+/**
+ * @title RewardsManagerV5Storage
+ * @author Edge & Node
+ * @notice Storage layout for RewardsManager V6
+ */
+contract RewardsManagerV6Storage is RewardsManagerV5Storage {
+    /// @notice Address of the rewards eligibility oracle contract
+    IRewardsEligibilityOracle public rewardsEligibilityOracle;
+}

packages/contracts/contracts/tests/MockRewardsEligibilityOracle.sol

@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+// solhint-disable named-parameters-mapping
+
+pragma solidity 0.7.6;
+
+import { IRewardsEligibilityOracle } from "@graphprotocol/interfaces/contracts/issuance/eligibility/IRewardsEligibilityOracle.sol";
+import { ERC165 } from "@openzeppelin/contracts/introspection/ERC165.sol";
+
+/**
+ * @title MockRewardsEligibilityOracle
+ * @author Edge & Node
+ * @notice A simple mock contract for the RewardsEligibilityOracle interface
+ * @dev A simple mock contract for the RewardsEligibilityOracle interface
+ */
+contract MockRewardsEligibilityOracle is IRewardsEligibilityOracle, ERC165 {
+    /// @dev Mapping to store eligibility status for each indexer
+    mapping(address => bool) private eligible;
+
+    /// @dev Mapping to track which indexers have been explicitly set
+    mapping(address => bool) private isSet;
+
+    /// @dev Default response for indexers not explicitly set
+    bool private defaultResponse;
+
+    /**
+     * @notice Constructor
+     * @param newDefaultResponse Default response for isEligible
+     */
+    constructor(bool newDefaultResponse) {
+        defaultResponse = newDefaultResponse;
+    }
+
+    /**
+     * @notice Set whether a specific indexer is eligible
+     * @param indexer The indexer address
+     * @param eligibility Whether the indexer is eligible
+     */
+    function setIndexerEligible(address indexer, bool eligibility) external {
+        eligible[indexer] = eligibility;
+        isSet[indexer] = true;
+    }
+
+    /**
+     * @notice Set the default response for indexers not explicitly set
+     * @param newDefaultResponse The default response
+     */
+    function setDefaultResponse(bool newDefaultResponse) external {
+        defaultResponse = newDefaultResponse;
+    }
+
+    /**
+     * @inheritdoc IRewardsEligibilityOracle
+     */
+    function isEligible(address indexer) external view override returns (bool) {
+        // If the indexer has been explicitly set, return that value
+        if (isSet[indexer]) {
+            return eligible[indexer];
+        }
+
+        // Otherwise return the default response
+        return defaultResponse;
+    }
+
+    /**
+     * @inheritdoc ERC165
+     */
+    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
+        return interfaceId == type(IRewardsEligibilityOracle).interfaceId || super.supportsInterface(interfaceId);
+    }
+}

packages/contracts/test/tests/unit/rewards/rewards.test.ts

@@ -190,7 +190,7 @@ describe('Rewards', () => {
       })
     })
 
-    describe.skip('rewards eligibility oracle', function () {
+    describe('rewards eligibility oracle', function () {
       it('should reject setRewardsEligibilityOracle if unauthorized', async function () {
         const MockRewardsEligibilityOracleFactory = await hre.ethers.getContractFactory(
           'contracts/tests/MockRewardsEligibilityOracle.sol:MockRewardsEligibilityOracle',
@@ -893,7 +893,7 @@ describe('Rewards', () => {
         await expect(tx).emit(rewardsManager, 'RewardsDenied').withArgs(indexer1.address, allocationID1)
       })
 
-      it.skip('should deny rewards due to rewards eligibility oracle', async function () {
+      it('should deny rewards due to rewards eligibility oracle', async function () {
         // Setup rewards eligibility oracle that denies rewards for indexer1
         const MockRewardsEligibilityOracleFactory = await hre.ethers.getContractFactory(
           'contracts/tests/MockRewardsEligibilityOracle.sol:MockRewardsEligibilityOracle',
@@ -923,7 +923,7 @@ describe('Rewards', () => {
           .withArgs(indexer1.address, allocationID1, expectedIndexingRewards)
       })
 
-      it.skip('should allow rewards when rewards eligibility oracle approves', async function () {
+      it('should allow rewards when rewards eligibility oracle approves', async function () {
         // Setup rewards eligibility oracle that allows rewards for indexer1
         const MockRewardsEligibilityOracleFactory = await hre.ethers.getContractFactory(
           'contracts/tests/MockRewardsEligibilityOracle.sol:MockRewardsEligibilityOracle',

packages/interfaces/contracts/contracts/rewards/IRewardsManager.sol

@@ -43,6 +43,12 @@ interface IRewardsManager {
      */
     function setSubgraphService(address subgraphService) external;
 
+    /**
+     * @notice Set the rewards eligibility oracle address
+     * @param newRewardsEligibilityOracle The address of the rewards eligibility oracle
+     */
+    function setRewardsEligibilityOracle(address newRewardsEligibilityOracle) external;
+
     // -- Denylist --
 
     /**

packages/interfaces/contracts/issuance/eligibility/IRewardsEligibilityOracle.sol

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+pragma solidity ^0.7.6 || ^0.8.0;
+
+/**
+ * @title IRewardsEligibilityOracle
+ * @author Edge & Node
+ * @notice Interface to check if an indexer is eligible to receive rewards
+ */
+interface IRewardsEligibilityOracle {
+    /**
+     * @notice Check if an indexer is eligible to receive rewards
+     * @param indexer Address of the indexer
+     * @return True if the indexer is eligible to receive rewards, false otherwise
+     */
+    function isEligible(address indexer) external view returns (bool);
+}

packages/interfaces/contracts/toolshed/IRewardsManagerToolshed.sol

@@ -36,4 +36,7 @@ interface IRewardsManagerToolshed is IRewardsManager {
     event SubgraphServiceSet(address indexed oldSubgraphService, address indexed newSubgraphService);
 
     function subgraphService() external view returns (address);
+
+    /// @inheritdoc IRewardsManager
+    function setRewardsEligibilityOracle(address newRewardsEligibilityOracle) external;
 }

packages/issuance/.markdownlint.json

@@ -0,0 +1,3 @@
+{
+  "extends": "../../.markdownlint.json"
+}

packages/issuance/.solcover.js

@@ -0,0 +1,19 @@
+module.exports = {
+  skipFiles: ['test/'],
+  providerOptions: {
+    mnemonic: 'myth like bonus scare over problem client lizard pioneer submit female collect',
+    network_id: 1337,
+  },
+  istanbulFolder: './test/reports/coverage',
+  configureYulOptimizer: true,
+  mocha: {
+    grep: '@skip-on-coverage',
+    invert: true,
+  },
+  reporter: ['html', 'lcov', 'text'],
+  reporterOptions: {
+    html: {
+      directory: './test/reports/coverage/html',
+    },
+  },
+}

packages/issuance/.solhint.json

@@ -0,0 +1,3 @@
+{
+  "extends": ["solhint:recommended", "./../../.solhint.json"]
+}