Add retry function (#574)

* Add retry method

* Add retry method test

contracts/Bridge.sol

@@ -58,6 +58,8 @@ contract Bridge is Pausable, AccessControl {
 
     event KeyRefresh();
 
+    event Retry(string txHash);
+
     modifier onlyAdmin() {
         _onlyAdmin();
         _;
@@ -301,6 +303,14 @@ contract Bridge is Pausable, AccessControl {
       emit KeyRefresh();
     }
 
+    /**
+        @notice This method is used to trigger the process for retrying failed deposits on the MPC side.
+        @param txHash Transaction hash which contains deposit that should be retried
+     */
+    function retry(string memory txHash) external {
+      emit Retry(txHash);
+    }
+
     /**
         @notice Returns a boolean value.
         @param domainID ID of chain deposit originated from.

test/contractBridge/publicMethods.js

@@ -0,0 +1,38 @@
+/**
+ * Copyright 2020 ChainSafe Systems
+ * SPDX-License-Identifier: LGPL-3.0-only
+ */
+ const TruffleAssert = require('truffle-assertions');
+ const Ethers = require('ethers');
+
+ const Helpers = require('../helpers');
+
+ const BridgeContract = artifacts.require("Bridge");
+
+ // This test does NOT include all getter methods, just
+ // getters that should work with only the constructor called
+ contract('Bridge - [public]', async (accounts) => {
+     const domainID = 1;
+
+     const txHash = "0x59d881e01ca682130e550e3576b6de760951fb45b1d5dd81342132f57920bbfa";
+
+     let BridgeInstance;
+
+
+     beforeEach(async () => {
+         BridgeInstance = await BridgeContract.new(domainID);
+
+        // set MPC address to unpause the Bridge
+        await BridgeInstance.endKeygen(Helpers.mpcAddress);
+     });
+
+     // Testing public methods
+
+     it('Should successfully emit Retry event', async () => {
+         const eventTx = await BridgeInstance.retry(txHash);
+
+         TruffleAssert.eventEmitted(eventTx, 'Retry', (event) => {
+          return event.txHash === txHash
+      });
+     });
+ });