Rewards/MyRewards: add etherscan link

WIP claim hash persistence

apps/rewards/app/components/App/App.js

@@ -199,6 +199,7 @@ class App extends React.Component {
   claimReward = reward => {
     this.props.api.claimReward(reward.rewardId + reward.claims)
       .subscribe(claimHash => {
+        console.log(claimHash) 
         const { claimHashes } = this.state
         claimHashes[reward.rewardId] = claimHash
         this.setState({ claimHashes })

apps/rewards/app/components/Content/MyRewards.js

@@ -163,6 +163,10 @@ const StyledIcon = ({ Icon }) => (
   }}/>
 )
 
+StyledIcon.propTypes = {
+  Icon: PropTypes.node.isRequired,
+}
+
 const OverviewMain = styled.div`
   background-color: #f8fcfd;
 `

apps/rewards/contracts/Rewards.sol

@@ -31,7 +31,11 @@ contract Rewards is AragonApp {
     string private constant ERROR_MAX_OCCURRENCES = "OCURRENCES_LIMIT_REACHED";
     string private constant ERROR_START_BLOCK = "START_PERIOD_BEFORE_TOKEN_CREATION";
     string private constant ERROR_REWARD_CLAIMED = "REWARD_ALREADY_CLAIMED";
+    string private constant ERROR_REWARD_NOT_CLAIMED = "REWARD_NOT_YET_CLAIMED";
+    string private constant ERROR_CLAIM_HASH_EXISTS = "CLAIM_HASH_ALREADY_EXISTS";
+    string private constant ERROR_CLAIM_HASH_NONEXISTENT = "CLAIM_HASH_DOES_NOT_EXIST";
     string private constant ERROR_ZERO_DURATION = "DURATION_MUST_BE_AT_LEAST_ONE_BLOCK";
+
     string private constant ERROR_ZERO_OCCURRENCE = "OCCURRENCES_LESS_THAN_ONE";
     string private constant ERROR_ZERO_REWARD = "NO_REWARD_TO_CLAIM";
     string private constant ERROR_EXISTS = "REWARD_DOES_NOT_EXIST";
@@ -61,9 +65,14 @@ contract Rewards is AragonApp {
     /// Public vault that holds the funds
     Vault public vault;
 
+    /// Claim hashes by reward and claimant
+    /// reward -> user -> hash
+    mapping(uint256 => mapping(address => string)) claimHashes;
+
     /// Events
     event RewardAdded(uint256 rewardId); /// Emitted when a new reward is created
     event RewardClaimed(uint256 rewardId); /// Emitted when a reward is claimed
+    event ClaimHashSet(uint256 rewardID, address claimant, string claimHash);
 
     /**
      * @notice Initialize Rewards app for Vault at `_vault`
@@ -101,6 +110,44 @@ contract Rewards is AragonApp {
         return rewardAmount;
     }
 
+    /**
+     * @notice Stores proof of a user claiming a reward
+     * @dev Updates `userclaimHashes` with the hash of a claim transaction for a 
+     * specific reward that has been claimed by the current user
+     * @param _rewardID The ID of the reward
+     * @param _claimHash The hash of the reward's claim transaction
+     */
+    function setClaimHash(uint256 _rewardID, string _claimHash)
+        external isInitialized
+    {
+        require(_rewardID < rewardsRegistryLength, ERROR_EXISTS);
+        Reward storage reward = rewards[_rewardID];
+        require(reward.timeClaimed[msg.sender] != 0, ERROR_REWARD_NOT_CLAIMED);
+        require(claimHashes[_rewardID][msg.sender] == 0,
+                ERROR_CLAIM_HASH_EXISTS);
+        claimHashes[_rewardID][msg.sender] = _claimHash;
+        emit ClaimHashSet(_rewardID, msg.sender, _claimHash);
+    }
+
+    /**
+     * @notice Retrieves proof of a user claiming a reward
+     * @dev Gets a claim hash from `userClaimHashes` given its claimant and 
+     * reward id
+     * @param _rewardID The ID of the claimed reward
+     * @param _claimant The address of the user who claimed the reward
+     * @return claimHash The claim hash for that particular reward and claimant
+     */
+    function getClaimHash(address _claimant, uint256 _rewardID)
+        external view isInitialized returns (string claimHash)
+    {
+        require(_rewardID < rewardsRegistryLength, ERROR_EXISTS);
+        Reward storage reward = rewards[_rewardID];
+        require(reward.timeClaimed[msg.sender] != 0, ERROR_REWARD_NOT_CLAIMED);
+        require(claimHashes[_rewardID][msg.sender] != 0,
+                ERROR_CLAIM_HASH_NONEXISTENT);
+        claimHash = claimHashes[_rewardID][_claimant];
+    }
+
     /**
      * @notice Get total rewards count
      * @dev Gets the lenght of the rewards registry array

apps/rewards/test/Rewards.test.js

@@ -195,6 +195,10 @@ contract('Rewards', accounts => {
         assert.notEqual(rewardInformation[10].toNumber(), 0, 'reward should have nonzero timestamp')
       })
 
+      it('sets the claim hash', async () => {
+        await app.setClaimHash()
+      })
+
       it('receives rewards merit', async () => {
         await app.claimReward(meritRewardIds[0])
         const balance = await rewardToken.balanceOf(root)