Made drip rate configurable in the ComptrollerV2 (#250)

contracts/comptroller/ComptrollerV2.sol

@@ -7,6 +7,7 @@ import "@openzeppelin/contracts-upgradeable/utils/SafeCastUpgradeable.sol";
 import "@openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol";
 import "@openzeppelin/contracts-upgradeable/proxy/Initializable.sol";
 import "@pooltogether/fixed-point/contracts/FixedPoint.sol";
+import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
 
 import "../utils/ExtendedSafeCast.sol";
 import "../token/TokenListener.sol";
@@ -15,7 +16,7 @@ import "../token/TokenListener.sol";
 /// @notice The tokens are dripped at a "drip rate per second".  This is the number of tokens that
 /// are dripped each second.  A user's share of the dripped tokens is based on how many 'measure' tokens they hold.
 /* solium-disable security/no-block-members */
-contract ComptrollerV2 is Initializable, TokenListener {
+contract ComptrollerV2 is OwnableUpgradeable, TokenListener {
   using SafeMathUpgradeable for uint256;
   using SafeCastUpgradeable for uint256;
   using ExtendedSafeCast for uint256;
@@ -35,6 +36,10 @@ contract ComptrollerV2 is Initializable, TokenListener {
     uint256 newTokens
   );
 
+  event DripRateChanged(
+    uint256 dripRatePerSecond
+  );
+
   struct UserState {
     uint128 lastExchangeRateMantissa;
     uint128 balance;
@@ -70,11 +75,11 @@ contract ComptrollerV2 is Initializable, TokenListener {
     IERC20Upgradeable _measure,
     uint256 _dripRatePerSecond
   ) public initializer {
-    require(_dripRatePerSecond > 0, "ComptrollerV2/dripRate-gt-zero");
+    __Ownable_init();
+    lastDripTimestamp = _currentTime();
     asset = _asset;
     measure = _measure;
-    dripRatePerSecond = _dripRatePerSecond;
-    lastDripTimestamp = _currentTime();
+    setDripRatePerSecond(_dripRatePerSecond);
 
     emit Initialized(
       asset,
@@ -136,6 +141,17 @@ contract ComptrollerV2 is Initializable, TokenListener {
     return newTokens;
   }
 
+  function setDripRatePerSecond(uint256 _dripRatePerSecond) public onlyOwner {
+    require(_dripRatePerSecond > 0, "ComptrollerV2/dripRate-gt-zero");
+
+    // ensure we're all caught up
+    drip();
+
+    dripRatePerSecond = _dripRatePerSecond;
+
+    emit DripRateChanged(dripRatePerSecond);
+  }
+
   /// @notice Captures new tokens for a user
   /// @dev This must be called before changes to the user's balance (i.e. before mint, transfer or burns)
   /// @param user The user to capture tokens for

contracts/comptroller/ComptrollerV2ProxyFactory.sol

@@ -31,6 +31,7 @@ contract ComptrollerV2ProxyFactory is ProxyFactory {
     comptroller.initialize(
       _asset, _measure, _dripRatePerSecond
     );
+    comptroller.transferOwnership(msg.sender);
     return comptroller;
   }
 

test/ComptrollerV2.test.js

@@ -295,4 +295,22 @@ describe('ComptrollerV2', () => {
       expect(await dripToken.balanceOf(wallet._address)).to.equal(toWei('5'))
     })
   })
+
+  describe('setDripRatePerSecond()', () => {
+    it('should allow the owner to change the drip rate', async () => {
+      await expect(comptroller.setDripRatePerSecond('1'))
+        .to.emit(comptroller, 'DripRateChanged')
+        .withArgs('1')
+    })
+
+    it('should not allow anyone else to set drip rate', async () => {
+      await expect(comptroller.connect(wallet2).setDripRatePerSecond('1'))
+        .to.be.revertedWith('Ownable: caller is not the owner')
+    })
+
+    it('requires that the rip rate be greater than zero', async () => {
+      await expect(comptroller.setDripRatePerSecond('0'))
+        .to.be.revertedWith('ComptrollerV2/dripRate-gt-zero')
+    })
+  })
 })

test/ComptrollerV2ProxyFactory.test.js

@@ -37,6 +37,7 @@ describe('ComptrollerV2ProxyFactory', () => {
       expect(await comptrollerV2.asset()).to.equal(asset.address)
       expect(await comptrollerV2.measure()).to.equal(measure.address)
       expect(await comptrollerV2.dripRatePerSecond()).to.equal(ethers.utils.parseEther('0.01'))
+      expect(await comptrollerV2.owner()).to.equal(wallet._address)
 
     })
   })