Fix: Randomizer.ai contract upgrade and callback signature change

contracts/deploy/00-home-chain-arbitration.ts

@@ -15,7 +15,7 @@ const pnkByChain = new Map<HomeChains, string>([
 
 const randomizerByChain = new Map<HomeChains, string>([
   [HomeChains.ARBITRUM_ONE, "0x00"],
-  [HomeChains.ARBITRUM_GOERLI, "0xE1B6CcAc0BB0355C01A049e78909231Bfa13620B"],
+  [HomeChains.ARBITRUM_GOERLI, "0x57F7a8aA8291A04B325F3f0d2c4d03353d3Ef25f"],
 ]);
 
 const deployArbitration: DeployFunction = async (hre: HardhatRuntimeEnvironment) => {

contracts/deploy/00-rng.ts

@@ -0,0 +1,72 @@
+import { HardhatRuntimeEnvironment } from "hardhat/types";
+import { DeployFunction } from "hardhat-deploy/types";
+import { BigNumber } from "ethers";
+import { DisputeKitClassic, RandomizerRNG } from "../typechain-types";
+
+enum HomeChains {
+  ARBITRUM_ONE = 42161,
+  ARBITRUM_GOERLI = 421613,
+  HARDHAT = 31337,
+}
+
+const pnkByChain = new Map<HomeChains, string>([
+  [HomeChains.ARBITRUM_ONE, "0x330bD769382cFc6d50175903434CCC8D206DCAE5"],
+  [HomeChains.ARBITRUM_GOERLI, "0x4DEeeFD054434bf6721eF39Aa18EfB3fd0D12610"],
+]);
+
+const randomizerByChain = new Map<HomeChains, string>([
+  [HomeChains.ARBITRUM_ONE, "0x00"],
+  [HomeChains.ARBITRUM_GOERLI, "0x57F7a8aA8291A04B325F3f0d2c4d03353d3Ef25f"],
+]);
+
+const deployArbitration: DeployFunction = async (hre: HardhatRuntimeEnvironment) => {
+  const { deployments, getNamedAccounts, getChainId } = hre;
+  const { deploy, execute } = deployments;
+  const { AddressZero } = hre.ethers.constants;
+  const RNG_LOOKAHEAD = 20;
+
+  // fallback to hardhat node signers on local network
+  const deployer = (await getNamedAccounts()).deployer ?? (await hre.ethers.getSigners())[0].address;
+  const chainId = Number(await getChainId());
+  console.log("deploying to %s with deployer %s", HomeChains[chainId], deployer);
+
+  if (chainId === HomeChains.HARDHAT) {
+    pnkByChain.set(
+      HomeChains.HARDHAT,
+      (
+        await deploy("PNK", {
+          from: deployer,
+          log: true,
+        })
+      ).address
+    );
+    randomizerByChain.set(
+      HomeChains.HARDHAT,
+      (
+        await deploy("RandomizerMock", {
+          from: deployer,
+          args: [],
+          log: true,
+        })
+      ).address
+    );
+  }
+
+  const randomizer = randomizerByChain.get(Number(await getChainId())) ?? AddressZero;
+  const rng = await deploy("RandomizerRNG", {
+    from: deployer,
+    args: [randomizer, deployer],
+    log: true,
+  });
+
+  const disputeKit = (await hre.ethers.getContract("DisputeKitClassic")) as DisputeKitClassic;
+  await disputeKit.changeRandomNumberGenerator(rng.address, RNG_LOOKAHEAD);
+};
+
+deployArbitration.tags = ["HomeChain", "RNG"];
+deployArbitration.skip = async ({ getChainId }) => {
+  const chainId = Number(await getChainId());
+  return !HomeChains[chainId];
+};
+
+export default deployArbitration;

contracts/src/rng/IRandomizer.sol

@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8;
+
 // Randomizer protocol interface
 interface IRandomizer {
     function request(uint256 callbackGasLimit) external returns (uint256);

contracts/src/rng/RandomizerRNG.sol

@@ -10,12 +10,16 @@ import "./IRandomizer.sol";
  *  https://randomizer.ai/
  */
 contract RandomizerRNG is RNG {
-    uint256 public constant CALLBACK_GAS_LIMIT = 50000;
     address public governor; // The address that can withdraw funds.
+    uint256 public callbackGasLimit = 50000; // Gas limit for the randomizer callback
 
     IRandomizer public randomizer; // Randomizer address.
-    mapping(uint128 => uint256) public randomNumbers; // randomNumbers[requestID] is the random number for this request id, 0 otherwise.
-    mapping(address => uint128) public requesterToID; // Maps the requester to his latest request ID.
+    mapping(uint256 => uint256) public randomNumbers; // randomNumbers[requestID] is the random number for this request id, 0 otherwise.
+    mapping(address => uint256) public requesterToID; // Maps the requester to his latest request ID.
+
+    // ************************************* //
+    // *        Function Modifiers         * //
+    // ************************************* //
 
     modifier onlyByGovernor() {
         require(governor == msg.sender, "Governor only");
@@ -31,44 +35,70 @@ contract RandomizerRNG is RNG {
         governor = _governor;
     }
 
+    // ************************ //
+    // *      Governance      * //
+    // ************************ //
+
     /** @dev Changes the governor of the contract.
      *  @param _governor The new governor.
      */
     function changeGovernor(address _governor) external onlyByGovernor {
         governor = _governor;
     }
 
+    /** @dev Change the Randomizer callback gas limit.
+     *  @param _callbackGasLimit the new limit.
+     */
+    function setCallbackGasLimit(uint256 _callbackGasLimit) external onlyByGovernor {
+        callbackGasLimit = _callbackGasLimit;
+    }
+
+    /** @dev Change the Randomizer address.
+     *  @param _randomizer the new Randomizer address.
+     */
+    function setRandomizer(address _randomizer) external onlyByGovernor {
+        randomizer = IRandomizer(_randomizer);
+    }
+
     /**
-     *  @dev Request a random number. The id of the request is tied to the sender.
+     *  @dev Allows the governor to withdraw randomizer funds.
+     *  @param _amount Amount to withdraw in wei.
      */
-    function requestRandomness(uint256 /*_block*/) external override {
-        uint128 id = uint128(randomizer.request(CALLBACK_GAS_LIMIT));
-        requesterToID[msg.sender] = id;
+    function randomizerWithdraw(uint256 _amount) external onlyByGovernor {
+        randomizer.clientWithdrawTo(msg.sender, _amount);
     }
 
+    // ************************************* //
+    // *         State Modifiers           * //
+    // ************************************* //
+
     /**
-     *  @dev Return the random number.
-     *  @return randomNumber The random number or 0 if it is not ready or has not been requested.
+     *  @dev Request a random number. The id of the request is tied to the sender.
      */
-    function receiveRandomness(uint256 /*_block*/) external view override returns (uint256 randomNumber) {
-        // Get the latest request ID for this requester.
-        uint128 id = requesterToID[msg.sender];
-        randomNumber = randomNumbers[id];
+    function requestRandomness(uint256 /*_block*/) external override {
+        uint256 id = randomizer.request(callbackGasLimit);
+        requesterToID[msg.sender] = id;
     }
 
     /**
      *  @dev Callback function called by the randomizer contract when the random value is generated.
      */
-    function randomizerCallback(uint128 _id, bytes32 _value) external {
-        require(msg.sender == address(randomizer), "Caller not Randomizer");
+    function randomizerCallback(uint256 _id, bytes32 _value) external {
+        require(msg.sender == address(randomizer), "Randomizer only");
         randomNumbers[_id] = uint256(_value);
     }
 
+    // ************************************* //
+    // *           Public Views            * //
+    // ************************************* //
+
     /**
-     *  @dev Allows the governor to withdraw randomizer funds.
-     *  @param _amount Amount to withdraw in wei.
+     *  @dev Return the random number.
+     *  @return randomNumber The random number or 0 if it is not ready or has not been requested.
      */
-    function randomizerWithdraw(uint256 _amount) external onlyByGovernor {
-        randomizer.clientWithdrawTo(msg.sender, _amount);
+    function receiveRandomness(uint256 /*_block*/) external view override returns (uint256 randomNumber) {
+        // Get the latest request ID for this requester.
+        uint256 id = requesterToID[msg.sender];
+        randomNumber = randomNumbers[id];
     }
 }

contracts/src/rng/mock/RandomizerMock.sol

@@ -15,7 +15,7 @@ contract RandomizerMock is IRandomizer {
         revert("Not Implemented");
     }
 
-    function relay(RandomizerRNG _rng, uint128 _id, bytes32 _value) external {
+    function relay(RandomizerRNG _rng, uint256 _id, bytes32 _value) external {
         _rng.randomizerCallback(_id, _value);
     }
 }