fix #526 - add upgrade mechanism to registry (#625)

* fix #526

* address pr comments

* s/latest/current,add comments

* change currentVersion to track numberOfVersions to behave like a counter.

l1-contracts/src/core/Rollup.sol

@@ -61,9 +61,11 @@ contract Rollup is Decoder {
     rollupStateHash = newStateHash;
 
     // @todo (issue #605) handle fee collector
+    // @todo: (issue #624) handle different versions
     IInbox inbox = REGISTRY.getInbox();
     inbox.batchConsume(l1ToL2Msgs, msg.sender);
 
+    // @todo: (issue #624) handle different versions
     IOutbox outbox = REGISTRY.getOutbox();
     outbox.sendL1Messages(l2ToL1Msgs);
 

l1-contracts/src/core/interfaces/messagebridge/IRegistry.sol

@@ -7,11 +7,16 @@ import {IInbox} from "./IInbox.sol";
 import {IOutbox} from "./IOutbox.sol";
 
 interface IRegistry {
-  function getL1L2Addresses() external view returns (DataStructures.L1L2Addresses memory);
-
   function getRollup() external view returns (IRollup);
 
   function getInbox() external view returns (IInbox);
 
   function getOutbox() external view returns (IOutbox);
+
+  function getSnapshot(uint256 _version)
+    external
+    view
+    returns (DataStructures.RegistrySnapshot memory);
+
+  function getCurrentSnapshot() external view returns (DataStructures.RegistrySnapshot memory);
 }

l1-contracts/src/core/libraries/DataStructures.sol

@@ -65,14 +65,16 @@ library DataStructures {
   }
 
   /**
-   * @notice Struct for storing address of cross communication components
+   * @notice Struct for storing address of cross communication components and the block number when it was updated
    * @param rollup - The address of the rollup contract
    * @param inbox - The address of the inbox contract
    * @param outbox - The address of the outbox contract
+   * @param blockNumber - The block number of the snapshot
    */
-  struct L1L2Addresses {
+  struct RegistrySnapshot {
     address rollup;
     address inbox;
     address outbox;
+    uint256 blockNumber;
   }
 }

l1-contracts/src/core/messagebridge/Inbox.sol

@@ -24,6 +24,7 @@ contract Inbox is IInbox {
   mapping(address account => uint256 balance) public feesAccrued;
 
   modifier onlyRollup() {
+    // @todo: (issue #624) handle different versions
     if (msg.sender != address(REGISTRY.getRollup())) revert Errors.Inbox__Unauthorized();
     _;
   }

l1-contracts/src/core/messagebridge/Outbox.sol

@@ -24,6 +24,7 @@ contract Outbox is IOutbox {
   mapping(bytes32 entryKey => DataStructures.Entry entry) internal entries;
 
   modifier onlyRollup() {
+    // @todo: (issue #624) handle different versions
     if (msg.sender != address(REGISTRY.getRollup())) revert Errors.Outbox__Unauthorized();
     _;
   }

l1-contracts/src/core/messagebridge/Registry.sol

@@ -14,28 +14,73 @@ import {DataStructures} from "@aztec/core/libraries/DataStructures.sol";
  * @notice Keeps track of important information for L1<>L2 communication.
  */
 contract Registry is IRegistry {
-  // TODO(rahul) - https://github.com/AztecProtocol/aztec-packages/issues/526
-  // Need to create a snashot of addresses per version!
+  uint256 public numberOfVersions;
+  DataStructures.RegistrySnapshot internal currentSnapshot;
+  mapping(uint256 version => DataStructures.RegistrySnapshot snapshot) internal snapshots;
 
-  DataStructures.L1L2Addresses public addresses;
-
-  function setAddresses(address _rollup, address _inbox, address _outbox) public {
-    addresses = DataStructures.L1L2Addresses(_rollup, _inbox, _outbox);
-  }
-
-  function getL1L2Addresses() external view override returns (DataStructures.L1L2Addresses memory) {
-    return addresses;
+  // todo: this function has to be permissioned.
+  /**
+   * @notice Creates a new snapshot of the registry
+   * @param _rollup - The address of the rollup contract
+   * @param _inbox - The address of the inbox contract
+   * @param _outbox - The address of the outbox contract
+   */
+  function upgrade(address _rollup, address _inbox, address _outbox) external {
+    DataStructures.RegistrySnapshot memory newSnapshot =
+      DataStructures.RegistrySnapshot(_rollup, _inbox, _outbox, block.number);
+    currentSnapshot = newSnapshot;
+    snapshots[numberOfVersions++] = newSnapshot;
   }
 
+  /**
+   * @notice Returns the rollup contract
+   * @return The rollup contract (of type IRollup)
+   */
   function getRollup() external view override returns (IRollup) {
-    return IRollup(addresses.rollup);
+    return IRollup(currentSnapshot.rollup);
   }
 
+  /**
+   * @notice Returns the inbox contract
+   * @return The inbox contract (of type IInbox)
+   */
   function getInbox() external view override returns (IInbox) {
-    return IInbox(addresses.inbox);
+    return IInbox(currentSnapshot.inbox);
   }
 
+  /**
+   * @notice Returns the outbox contract
+   * @return The outbox contract (of type IOutbox)
+   */
   function getOutbox() external view override returns (IOutbox) {
-    return IOutbox(addresses.outbox);
+    return IOutbox(currentSnapshot.outbox);
+  }
+
+  /**
+   * @notice Fetches a snapshot of the registry indicated by `version`
+   * @dev the version is 0 indexed, so the first snapshot is version 0.
+   * @param _version - The version of the rollup to return (i.e. which snapshot)
+   * @return the snapshot
+   */
+  function getSnapshot(uint256 _version)
+    external
+    view
+    override
+    returns (DataStructures.RegistrySnapshot memory)
+  {
+    return snapshots[_version];
+  }
+
+  /**
+   * @notice Returns the current snapshot of the registry
+   * @return The current snapshot
+   */
+  function getCurrentSnapshot()
+    external
+    view
+    override
+    returns (DataStructures.RegistrySnapshot memory)
+  {
+    return currentSnapshot;
   }
 }

l1-contracts/test/Inbox.t.sol

@@ -31,7 +31,7 @@ contract InboxTest is Test {
     address rollup = address(this);
     Registry registry = new Registry();
     inbox = new Inbox(address(registry));
-    registry.setAddresses(rollup, address(inbox), address(0x0));
+    registry.upgrade(rollup, address(inbox), address(0x0));
   }
 
   function _fakeMessage() internal view returns (DataStructures.L1ToL2Msg memory) {

l1-contracts/test/Outbox.t.sol

@@ -20,7 +20,7 @@ contract OutboxTest is Test {
     address rollup = address(this);
     Registry registry = new Registry();
     outbox = new Outbox(address(registry));
-    registry.setAddresses(rollup, address(0x0), address(outbox));
+    registry.upgrade(rollup, address(0x0), address(outbox));
   }
 
   function _fakeMessage() internal view returns (DataStructures.L2ToL1Msg memory) {

l1-contracts/test/Rollup.t.sol

@@ -32,7 +32,7 @@ contract RollupTest is DecoderTest {
     outbox = new Outbox(address(registry));
     rollup = new Rollup(registry);
 
-    registry.setAddresses(address(rollup), address(inbox), address(outbox));
+    registry.upgrade(address(rollup), address(inbox), address(outbox));
   }
 
   function testEmptyBlock() public override(DecoderTest) {

l1-contracts/test/portals/RNA.t.sol

@@ -34,7 +34,7 @@ contract RNATest is Test {
     inbox = new Inbox(address(registry));
     rollup = new Rollup(registry);
 
-    registry.setAddresses(address(rollup), address(inbox), address(outbox));
+    registry.upgrade(address(rollup), address(inbox), address(outbox));
 
     rna = new RollupNativeAsset();
     // Essentially deploying the rna contract on the 0xbeef address to make matching entry easy.

l1-contracts/test/portals/RollupNativeAsset.sol

@@ -27,6 +27,7 @@ contract RollupNativeAsset is ERC20 {
         )
     });
 
+    // @todo: (issue #624) handle different versions
     bytes32 entryKey = registry.getOutbox().consume(message);
 
     _mint(_recipient, _amount);

l1-contracts/test/portals/TokenPortal.sol

@@ -36,6 +36,7 @@ contract TokenPortal {
     returns (bytes32)
   {
     // Preamble
+    // @todo: (issue #624) handle different versions
     IInbox inbox = registry.getInbox();
     DataStructures.L2Actor memory actor = DataStructures.L2Actor(l2TokenAddress, 1);
 

l1-contracts/test/portals/TokenPortal.t.sol

@@ -45,7 +45,7 @@ contract TokenPortalTest is Test {
     outbox = new Outbox(address(registry));
     rollup = new Rollup(registry);
 
-    registry.setAddresses(address(rollup), address(inbox), address(outbox));
+    registry.upgrade(address(rollup), address(inbox), address(outbox));
 
     portalERC20 = new PortalERC20();
     tokenPortal = new TokenPortal();

yarn-project/end-to-end/src/deploy_l1_contracts.ts

@@ -120,7 +120,7 @@ export const deployL1Contracts = async (
     publicClient,
     walletClient,
   });
-  await registryContract.write.setAddresses(
+  await registryContract.write.upgrade(
     [getAddress(rollupAddress.toString()), getAddress(inboxAddress.toString()), getAddress(outboxAddress.toString())],
     { account },
   );