Update refreshKey event (#596)

* Update refreshKey event to emit hash string

* Update refreshKey signature

* Update refreshKey tests

contracts/Bridge.sol

@@ -67,7 +67,7 @@ contract Bridge is Pausable, Context {
 
     event EndKeygen();
 
-    event KeyRefresh();
+    event KeyRefresh(string hash);
 
     event Retry(string txHash);
 
@@ -364,9 +364,10 @@ contract Bridge is Pausable, Context {
         It's used to trigger the belonging process on the MPC side which also handles keygen function calls order.
         @notice Only callable by address that has the right to call the specific function,
         which is mapped in {functionAccess} in AccessControlSegregator contract.
+        @param hash Topology hash which prevents changes during refresh process.
      */
-    function refreshKey() external onlyAllowed {
-        emit KeyRefresh();
+    function refreshKey(string memory hash) external onlyAllowed {
+        emit KeyRefresh(hash);
     }
 
     /**

test/contractBridge/admin.js

@@ -22,6 +22,7 @@ contract('Bridge - [admin]', async (accounts) => {
     const expectedBridgeAdmin = accounts[0];
     const someAddress = "0xcafecafecafecafecafecafecafecafecafecafe";
     const nullAddress = "0x0000000000000000000000000000000000000000";
+    const topologyHash = "549f715f5b06809ada23145c2dc548db";
 
     const bytes32 = "0x0";
     let ADMIN_ROLE;
@@ -103,14 +104,16 @@ contract('Bridge - [admin]', async (accounts) => {
         await TruffleAssert.reverts(BridgeInstance.endKeygen(someAddress), "MPC address can't be updated");
     });
 
-    it('Should successfully emit "KeyRefresh" event if called by admin', async () => {
-        const startKeygenTx = await BridgeInstance.refreshKey();
+    it('Should successfully emit "KeyRefresh" event with expected hash value if called by admin', async () => {
+        const startKeygenTx = await BridgeInstance.refreshKey(topologyHash);
 
-        TruffleAssert.eventEmitted(startKeygenTx, 'KeyRefresh');
+        TruffleAssert.eventEmitted(startKeygenTx, 'KeyRefresh', (event) => {
+            return event.hash = topologyHash;
+        });
     });
 
     it('Should fail if "refreshKey" is called by non admin', async () => {
-        await assertOnlyAdmin(BridgeInstance.refreshKey);
+        await assertOnlyAdmin(BridgeInstance.refreshKey, topologyHash);
     });
 
     // Set Handler Address

test/helpers.js

@@ -235,7 +235,7 @@ const deployBridge = async (domainID, admin) => {
             "0xbd2a1820", // adminWithdraw
             "0x6ba6db6b", // startKeygen
             "0xd2e5fae9", // endKeygen
-            "0xf5f63b39", // refreshKey
+            "0xd8236744", // refreshKey
 
         ],
         Array(13).fill(admin)