Extend ERC677BridgeToken contract for xDai-POA bridge

contracts/ERC677BridgeToken.sol

@@ -75,7 +75,7 @@ contract ERC677BridgeToken is
     }
 
     function isContract(address _addr)
-        private
+        internal
         view
         returns (bool)
     {

contracts/ERC677BridgeTokenRewardable.sol

@@ -0,0 +1,66 @@
+pragma solidity 0.4.24;
+
+import "./ERC677BridgeToken.sol";
+
+
+contract ERC677BridgeTokenRewardable is ERC677BridgeToken {
+
+    address public blockRewardContract;
+    address public validatorSetContract;
+
+    constructor(
+        string _name,
+        string _symbol,
+        uint8 _decimals
+    ) public ERC677BridgeToken(_name, _symbol, _decimals) {}
+
+    function setBlockRewardContract(address _blockRewardContract) onlyOwner public {
+        require(_blockRewardContract != address(0) && isContract(_blockRewardContract));
+        blockRewardContract = _blockRewardContract;
+    }
+
+    function setValidatorSetContract(address _validatorSetContract) onlyOwner public {
+        require(_validatorSetContract != address(0) && isContract(_validatorSetContract));
+        validatorSetContract = _validatorSetContract;
+    }
+
+    modifier onlyBlockRewardContract() {
+        require(msg.sender == blockRewardContract);
+        _;
+    }
+
+    modifier onlyValidatorSetContract() {
+        require(msg.sender == validatorSetContract);
+        _;
+    }
+
+    function mintReward(address[] _receivers, uint256[] _rewards) external onlyBlockRewardContract {
+        for (uint256 i = 0; i < _receivers.length; i++) {
+            address to = _receivers[i];
+            uint256 amount = _rewards[i];
+
+            // Mint `amount` for `to`
+            totalSupply_ = totalSupply_.add(amount);
+            balances[to] = balances[to].add(amount);
+            emit Mint(to, amount);
+            emit Transfer(address(0), to, amount);
+        }
+    }
+
+    function stake(address _staker, uint256 _amount) external onlyValidatorSetContract {
+        // Transfer `_amount` from `_staker` to `validatorSetContract`
+        require(_amount <= balances[_staker]);
+        balances[_staker] = balances[_staker].sub(_amount);
+        balances[validatorSetContract] = balances[validatorSetContract].add(_amount);
+        emit Transfer(_staker, validatorSetContract, _amount);
+    }
+
+    function withdraw(address _staker, uint256 _amount) external onlyValidatorSetContract {
+        // Transfer `_amount` from `validatorSetContract` to `_staker`
+        require(_amount <= balances[validatorSetContract]);
+        balances[validatorSetContract] = balances[validatorSetContract].sub(_amount);
+        balances[_staker] = balances[_staker].add(_amount);
+        emit Transfer(validatorSetContract, _staker, _amount);
+    }
+
+}

contracts/test/ValidatorSet.sol

@@ -0,0 +1,6 @@
+pragma solidity 0.4.24;
+
+
+contract ValidatorSet {
+    constructor() {}
+}

deploy/.env.example

@@ -20,7 +20,7 @@ HOME_MIN_AMOUNT_PER_TX=500000000000000000
 HOME_REQUIRED_BLOCK_CONFIRMATIONS=1
 HOME_GAS_PRICE=1000000000
 
-#for bridge erc to native mode
+#for bridge erc_to_native and native_to_erc mode
 BLOCK_REWARD_ADDRESS=
 
 FOREIGN_RPC_URL=https://sokol.poa.network
@@ -39,3 +39,7 @@ REQUIRED_NUMBER_OF_VALIDATORS=1
 #If several validators are used, list them separated by space without quotes
 #E.g. VALIDATORS=0x 0x 0x
 VALIDATORS=0x
+
+#for bridge native_to_erc mode
+DEPLOY_REWARDABLE_TOKEN=false
+DPOS_VALIDATOR_SET_ADDRESS=

deploy/README.md

@@ -123,6 +123,16 @@ REQUIRED_NUMBER_OF_VALIDATORS=1
 # the Foreign network to confirm that the finalized agreement was transferred
 # correctly to the Foreign network.
 VALIDATORS=0x 0x 0x
+
+# The flag defining whether to use ERC677BridgeTokenRewardable contract instead of
+# ERC677BridgeToken.
+DEPLOY_REWARDABLE_TOKEN=false
+# The address of ValidatorSet contract used by ERC677BridgeTokenRewardable contract.
+# Makes sense only when DEPLOY_REWARDABLE_TOKEN=true
+DPOS_VALIDATOR_SET_ADDRESS=0x
+# The address of BlockReward contract used by ERC677BridgeTokenRewardable contract.
+# Makes sense only when DEPLOY_REWARDABLE_TOKEN=true
+BLOCK_REWARD_ADDRESS=0x
 ```
 
 

deploy/src/loadEnv.js

@@ -61,7 +61,10 @@ if (BRIDGE_MODE === 'NATIVE_TO_ERC') {
     BRIDGEABLE_TOKEN_DECIMALS: envalid.num(),
     FOREIGN_DAILY_LIMIT: bigNumValidator(),
     FOREIGN_MAX_AMOUNT_PER_TX: bigNumValidator(),
-    FOREIGN_MIN_AMOUNT_PER_TX: bigNumValidator()
+    FOREIGN_MIN_AMOUNT_PER_TX: bigNumValidator(),
+    DEPLOY_REWARDABLE_TOKEN: envalid.bool(),
+    DPOS_VALIDATOR_SET_ADDRESS: addressValidator(),
+    BLOCK_REWARD_ADDRESS: addressValidator()
   }
 }
 if (BRIDGE_MODE === 'ERC_TO_ERC') {

deploy/src/native_to_erc/foreign.js

@@ -6,6 +6,7 @@ const { deployContract, privateKeyToAddress, sendRawTxForeign } = require('../de
 const { web3Foreign, deploymentPrivateKey, FOREIGN_RPC_URL } = require('../web3')
 
 const ERC677BridgeToken = require('../../../build/contracts/ERC677BridgeToken.json')
+const ERC677BridgeTokenRewardable = require('../../../build/contracts/ERC677BridgeTokenRewardable.json')
 const EternalStorageProxy = require('../../../build/contracts/EternalStorageProxy.json')
 const BridgeValidators = require('../../../build/contracts/BridgeValidators.json')
 const ForeignBridge = require('../../../build/contracts/ForeignBridgeNativeToErc.json')
@@ -27,7 +28,10 @@ const {
   BRIDGEABLE_TOKEN_SYMBOL,
   BRIDGEABLE_TOKEN_DECIMALS,
   HOME_DAILY_LIMIT,
-  HOME_MAX_AMOUNT_PER_TX
+  HOME_MAX_AMOUNT_PER_TX,
+  DEPLOY_REWARDABLE_TOKEN,
+  BLOCK_REWARD_ADDRESS,
+  DPOS_VALIDATOR_SET_ADDRESS
 } = env
 
 const DEPLOYMENT_ACCOUNT_ADDRESS = privateKeyToAddress(DEPLOYMENT_ACCOUNT_PRIVATE_KEY)
@@ -40,7 +44,7 @@ async function deployForeign() {
 
   console.log('\n[Foreign] deploying BRIDGEABLE_TOKEN_SYMBOL token')
   const erc677bridgeToken = await deployContract(
-    ERC677BridgeToken,
+    DEPLOY_REWARDABLE_TOKEN ? ERC677BridgeTokenRewardable : ERC677BridgeToken,
     [BRIDGEABLE_TOKEN_NAME, BRIDGEABLE_TOKEN_SYMBOL, BRIDGEABLE_TOKEN_DECIMALS],
     { from: DEPLOYMENT_ACCOUNT_ADDRESS, network: 'foreign', nonce: foreignNonce }
   )
@@ -212,6 +216,36 @@ async function deployForeign() {
   assert.strictEqual(Web3Utils.hexToNumber(setBridgeContract.status), 1, 'Transaction Failed')
   foreignNonce++
 
+  if (DEPLOY_REWARDABLE_TOKEN) {
+    console.log('\nset BlockReward contract on ERC677BridgeTokenRewardable')
+    const setBlockRewardContractData = await erc677bridgeToken.methods
+      .setBlockRewardContract(BLOCK_REWARD_ADDRESS)
+      .encodeABI({ from: DEPLOYMENT_ACCOUNT_ADDRESS })
+    const setBlockRewardContract = await sendRawTxForeign({
+      data: setBlockRewardContractData,
+      nonce: foreignNonce,
+      to: erc677bridgeToken.options.address,
+      privateKey: deploymentPrivateKey,
+      url: FOREIGN_RPC_URL
+    })
+    assert.equal(Web3Utils.hexToNumber(setBlockRewardContract.status), 1, 'Transaction Failed')
+    foreignNonce++
+
+    console.log('\nset ValidatorSet contract on ERC677BridgeTokenRewardable')
+    const setValidatorSetContractData = await erc677bridgeToken.methods
+      .setValidatorSetContract(DPOS_VALIDATOR_SET_ADDRESS)
+      .encodeABI({ from: DEPLOYMENT_ACCOUNT_ADDRESS })
+    const setValidatorSetContract = await sendRawTxForeign({
+      data: setValidatorSetContractData,
+      nonce: foreignNonce,
+      to: erc677bridgeToken.options.address,
+      privateKey: deploymentPrivateKey,
+      url: FOREIGN_RPC_URL
+    })
+    assert.equal(Web3Utils.hexToNumber(setValidatorSetContract.status), 1, 'Transaction Failed')
+    foreignNonce++
+  }
+
   console.log('transferring ownership of ERC677BridgeToken token to foreignBridge contract')
   const txOwnershipData = await erc677bridgeToken.methods
     .transferOwnership(foreignBridgeStorage.options.address)

test/mockContracts/ERC677BridgeTokenRewardableMock.sol

@@ -0,0 +1,22 @@
+pragma solidity 0.4.24;
+
+import '../../contracts/ERC677BridgeTokenRewardable.sol';
+
+
+contract ERC677BridgeTokenRewardableMock is ERC677BridgeTokenRewardable {
+
+    constructor(
+        string _name,
+        string _symbol,
+        uint8 _decimals
+    ) public ERC677BridgeTokenRewardable(_name, _symbol, _decimals) {}
+
+    function setBlockRewardContractMock(address _blockRewardContract) public {
+        blockRewardContract = _blockRewardContract;
+    }
+
+    function setValidatorSetContractMock(address _validatorSetContract) public {
+        validatorSetContract = _validatorSetContract;
+    }
+
+}