fix(validator): wait for l1 sync before processing block proposals

yarn-project/archiver/src/archiver-misc.test.ts

@@ -0,0 +1,193 @@
+import type { BlobClientInterface } from '@aztec/blob-client/client';
+import { GENESIS_ARCHIVE_ROOT } from '@aztec/constants';
+import type { EpochCache, EpochCommitteeInfo } from '@aztec/epoch-cache';
+import { DefaultL1ContractsConfig } from '@aztec/ethereum/config';
+import type { RollupContract } from '@aztec/ethereum/contracts';
+import type { ViemPublicClient } from '@aztec/ethereum/types';
+import { EpochNumber, SlotNumber } from '@aztec/foundation/branded-types';
+import { Buffer32 } from '@aztec/foundation/buffer';
+import { Fr } from '@aztec/foundation/curves/bn254';
+import { EthAddress } from '@aztec/foundation/eth-address';
+import { openTmpStore } from '@aztec/kv-store/lmdb-v2';
+import type { L1RollupConstants } from '@aztec/stdlib/epoch-helpers';
+import { getTelemetryClient } from '@aztec/telemetry-client';
+
+import { EventEmitter } from 'events';
+import { type MockProxy, mock } from 'jest-mock-extended';
+
+import { Archiver, type ArchiverEmitter } from './archiver.js';
+import type { ArchiverInstrumentation } from './modules/instrumentation.js';
+import { ArchiverL1Synchronizer } from './modules/l1_synchronizer.js';
+import { KVArchiverDataStore } from './store/kv_archiver_store.js';
+import { L2TipsCache } from './store/l2_tips_cache.js';
+
+describe('Archiver misc', () => {
+  let archiver: Archiver;
+  let synchronizer: MockProxy<ArchiverL1Synchronizer>;
+  let l1Constants: L1RollupConstants & { l1StartBlockHash: Buffer32; genesisArchiveRoot: Fr };
+
+  const L1_GENESIS_TIME = 1000n;
+  const SLOT_DURATION = 24;
+  const ETH_SLOT_DURATION = DefaultL1ContractsConfig.ethereumSlotDuration;
+  const EPOCH_DURATION = 4;
+
+  beforeEach(async () => {
+    l1Constants = {
+      l1GenesisTime: L1_GENESIS_TIME,
+      l1StartBlock: 0n,
+      l1StartBlockHash: Buffer32.random(),
+      epochDuration: EPOCH_DURATION,
+      slotDuration: SLOT_DURATION,
+      ethereumSlotDuration: ETH_SLOT_DURATION,
+      proofSubmissionEpochs: 1,
+      targetCommitteeSize: 48,
+      rollupManaLimit: Number.MAX_SAFE_INTEGER,
+      genesisArchiveRoot: new Fr(GENESIS_ARCHIVE_ROOT),
+    };
+
+    synchronizer = mock<ArchiverL1Synchronizer>();
+
+    const publicClient = mock<ViemPublicClient>();
+    const blobClient = mock<BlobClientInterface>();
+    const rollupContract = mock<RollupContract>();
+    const epochCache = mock<EpochCache>();
+    epochCache.getCommitteeForEpoch.mockResolvedValue({ committee: [] as EthAddress[] } as EpochCommitteeInfo);
+
+    const tracer = getTelemetryClient().getTracer('');
+    const instrumentation = mock<ArchiverInstrumentation>({ isEnabled: () => true, tracer });
+    const archiverStore = new KVArchiverDataStore(await openTmpStore('archiver_misc_test'), 1000, {
+      epochDuration: EPOCH_DURATION,
+    });
+    const events = new EventEmitter() as ArchiverEmitter;
+    const l2TipsCache = new L2TipsCache(archiverStore.blockStore);
+
+    archiver = new Archiver(
+      publicClient,
+      publicClient,
+      rollupContract,
+      {
+        registryAddress: EthAddress.random(),
+        governanceProposerAddress: EthAddress.random(),
+        slashFactoryAddress: EthAddress.random(),
+        slashingProposerAddress: EthAddress.random(),
+      },
+      archiverStore,
+      { pollingIntervalMs: 1000, batchSize: 1000, maxAllowedEthClientDriftSeconds: 300 },
+      blobClient,
+      instrumentation,
+      l1Constants,
+      synchronizer,
+      events,
+      l2TipsCache,
+    );
+  });
+
+  afterEach(async () => {
+    await archiver?.stop();
+  });
+
+  /** Returns the L1 timestamp at the start of an L2 slot. */
+  function slotStart(slot: number): bigint {
+    return L1_GENESIS_TIME + BigInt(slot) * BigInt(SLOT_DURATION);
+  }
+
+  /** Returns the L1 timestamp at the last L1 block of an L2 slot. */
+  function slotLastL1Block(slot: number): bigint {
+    // The last L1 block in an L2 slot is the one where the next L1 block falls in the next L2 slot.
+    // Start of next slot minus ethereumSlotDuration gives us the last L1 block still in this slot.
+    return slotStart(slot + 1) - BigInt(ETH_SLOT_DURATION);
+  }
+
+  describe('getSyncedL2SlotNumber', () => {
+    it('returns undefined before any sync', async () => {
+      synchronizer.getL1Timestamp.mockReturnValue(undefined);
+      expect(await archiver.getSyncedL2SlotNumber()).toBeUndefined();
+    });
+
+    it('returns undefined when L1 timestamp is before genesis', async () => {
+      synchronizer.getL1Timestamp.mockReturnValue(L1_GENESIS_TIME - 100n);
+      expect(await archiver.getSyncedL2SlotNumber()).toBeUndefined();
+    });
+
+    it('returns undefined at very start of slot 0 (next L1 block still in slot 0)', async () => {
+      // At genesis, next L1 block at genesis+12 is still in slot 0 (slot 0 covers [0, 24)).
+      synchronizer.getL1Timestamp.mockReturnValue(L1_GENESIS_TIME);
+      expect(await archiver.getSyncedL2SlotNumber()).toBeUndefined();
+    });
+
+    it('returns slot 0 when last L1 block of slot 0 has been synced', async () => {
+      // Last L1 block in slot 0: next L1 block (at ts+12) lands in slot 1.
+      synchronizer.getL1Timestamp.mockReturnValue(slotLastL1Block(0));
+      expect(await archiver.getSyncedL2SlotNumber()).toEqual(SlotNumber(0));
+    });
+
+    it('returns slot 0 at the start of slot 1', async () => {
+      synchronizer.getL1Timestamp.mockReturnValue(slotStart(1));
+      expect(await archiver.getSyncedL2SlotNumber()).toEqual(SlotNumber(0));
+    });
+
+    it('returns slot 4 when last L1 block of slot 4 has been synced', async () => {
+      synchronizer.getL1Timestamp.mockReturnValue(slotLastL1Block(4));
+      expect(await archiver.getSyncedL2SlotNumber()).toEqual(SlotNumber(4));
+    });
+
+    it('returns slot N-1 when L1 timestamp is mid-slot N', async () => {
+      // Mid slot 3: next L1 block (ts+12) still in slot 3, so slot 2 is last fully synced.
+      const midSlot3 = slotStart(3) + BigInt(ETH_SLOT_DURATION);
+      synchronizer.getL1Timestamp.mockReturnValue(midSlot3);
+      // next L1 block = midSlot3 + 12 = genesis + 3*24 + 24 = genesis + 96
+      // slot at genesis+96 = 96/24 = 4, so synced = 4-1 = 3
+      // Actually midSlot3 = genesis + 3*24 + 12 = genesis + 84
+      // next = genesis + 84 + 12 = genesis + 96, slot = 96/24 = 4, synced = 3
+      expect(await archiver.getSyncedL2SlotNumber()).toEqual(SlotNumber(3));
+    });
+  });
+
+  describe('getSyncedL2EpochNumber', () => {
+    // With epochDuration=4: epoch 0 = slots 0-3, epoch 1 = slots 4-7, epoch 2 = slots 8-11
+
+    it('returns undefined before any sync', async () => {
+      synchronizer.getL1Timestamp.mockReturnValue(undefined);
+      expect(await archiver.getSyncedL2EpochNumber()).toBeUndefined();
+    });
+
+    it('returns undefined when only part of epoch 0 is synced', async () => {
+      // Synced slot 0 => epoch 0 not fully synced, no previous epoch.
+      synchronizer.getL1Timestamp.mockReturnValue(slotLastL1Block(0));
+      expect(await archiver.getSyncedL2EpochNumber()).toBeUndefined();
+    });
+
+    it('returns undefined when synced to slot 2 (mid epoch 0)', async () => {
+      synchronizer.getL1Timestamp.mockReturnValue(slotLastL1Block(2));
+      expect(await archiver.getSyncedL2EpochNumber()).toBeUndefined();
+    });
+
+    it('returns epoch 0 when synced through last slot of epoch 0', async () => {
+      // Epoch 0 last slot = 3
+      synchronizer.getL1Timestamp.mockReturnValue(slotLastL1Block(3));
+      expect(await archiver.getSyncedL2EpochNumber()).toEqual(EpochNumber(0));
+    });
+
+    it('returns epoch 0 when synced to first slot of epoch 1', async () => {
+      // Synced slot 4 = first slot of epoch 1, so only epoch 0 is fully synced.
+      synchronizer.getL1Timestamp.mockReturnValue(slotLastL1Block(4));
+      expect(await archiver.getSyncedL2EpochNumber()).toEqual(EpochNumber(0));
+    });
+
+    it('returns epoch 0 when synced to slot 6 (mid epoch 1)', async () => {
+      synchronizer.getL1Timestamp.mockReturnValue(slotLastL1Block(6));
+      expect(await archiver.getSyncedL2EpochNumber()).toEqual(EpochNumber(0));
+    });
+
+    it('returns epoch 1 when synced through last slot of epoch 1', async () => {
+      // Epoch 1 last slot = 7
+      synchronizer.getL1Timestamp.mockReturnValue(slotLastL1Block(7));
+      expect(await archiver.getSyncedL2EpochNumber()).toEqual(EpochNumber(1));
+    });
+
+    it('returns epoch 1 when synced to mid epoch 2', async () => {
+      synchronizer.getL1Timestamp.mockReturnValue(slotLastL1Block(9));
+      expect(await archiver.getSyncedL2EpochNumber()).toEqual(EpochNumber(1));
+    });
+  });
+});

yarn-project/archiver/src/archiver.ts

@@ -22,9 +22,8 @@ import {
 import { PublishedCheckpoint } from '@aztec/stdlib/checkpoint';
 import {
   type L1RollupConstants,
-  getEpochNumberAtTimestamp,
+  getEpochAtSlot,
   getSlotAtNextL1Block,
-  getSlotAtTimestamp,
   getSlotRangeForEpoch,
   getTimestampRangeForEpoch,
 } from '@aztec/stdlib/epoch-helpers';
@@ -338,16 +337,35 @@ export class Archiver extends ArchiverDataSourceBase implements L2BlockSink, Tra
     return Promise.resolve(this.synchronizer.getL1Timestamp());
   }
 
-  public getL2SlotNumber(): Promise<SlotNumber | undefined> {
+  public getSyncedL2SlotNumber(): Promise<SlotNumber | undefined> {
     const l1Timestamp = this.synchronizer.getL1Timestamp();
-    return Promise.resolve(l1Timestamp === undefined ? undefined : getSlotAtTimestamp(l1Timestamp, this.l1Constants));
+    if (l1Timestamp === undefined) {
+      return Promise.resolve(undefined);
+    }
+    // The synced slot is the last L2 slot whose all L1 blocks have been processed.
+    // If the next L1 block (at l1Timestamp + ethereumSlotDuration) falls in slot N,
+    // then we've fully synced slot N-1.
+    const nextL1BlockSlot = getSlotAtNextL1Block(l1Timestamp, this.l1Constants);
+    if (Number(nextL1BlockSlot) === 0) {
+      return Promise.resolve(undefined);
+    }
+    return Promise.resolve(SlotNumber(nextL1BlockSlot - 1));
   }
 
-  public getL2EpochNumber(): Promise<EpochNumber | undefined> {
-    const l1Timestamp = this.synchronizer.getL1Timestamp();
-    return Promise.resolve(
-      l1Timestamp === undefined ? undefined : getEpochNumberAtTimestamp(l1Timestamp, this.l1Constants),
-    );
+  public async getSyncedL2EpochNumber(): Promise<EpochNumber | undefined> {
+    const syncedSlot = await this.getSyncedL2SlotNumber();
+    if (syncedSlot === undefined) {
+      return undefined;
+    }
+    // An epoch is fully synced when all its slots are synced.
+    // We check if syncedSlot is the last slot of its epoch; if so, that epoch is fully synced.
+    // Otherwise, only the previous epoch is fully synced.
+    const epoch = getEpochAtSlot(syncedSlot, this.l1Constants);
+    const [, endSlot] = getSlotRangeForEpoch(epoch, this.l1Constants);
+    if (syncedSlot >= endSlot) {
+      return epoch;
+    }
+    return Number(epoch) > 0 ? EpochNumber(Number(epoch) - 1) : undefined;
   }
 
   public async isEpochComplete(epochNumber: EpochNumber): Promise<boolean> {

yarn-project/archiver/src/modules/data_source_base.ts

@@ -46,9 +46,9 @@ export abstract class ArchiverDataSourceBase
 
   abstract getL2Tips(): Promise<L2Tips>;
 
-  abstract getL2SlotNumber(): Promise<SlotNumber | undefined>;
+  abstract getSyncedL2SlotNumber(): Promise<SlotNumber | undefined>;
 
-  abstract getL2EpochNumber(): Promise<EpochNumber | undefined>;
+  abstract getSyncedL2EpochNumber(): Promise<EpochNumber | undefined>;
 
   abstract isEpochComplete(epochNumber: EpochNumber): Promise<boolean>;
 

yarn-project/archiver/src/test/mock_l2_block_source.ts

@@ -447,11 +447,11 @@ export class MockL2BlockSource implements L2BlockSource, ContractDataSource {
     };
   }
 
-  getL2EpochNumber(): Promise<EpochNumber> {
+  getSyncedL2EpochNumber(): Promise<EpochNumber> {
     throw new Error('Method not implemented.');
   }
 
-  getL2SlotNumber(): Promise<SlotNumber> {
+  getSyncedL2SlotNumber(): Promise<SlotNumber> {
     throw new Error('Method not implemented.');
   }
 

yarn-project/archiver/src/test/noop_l1_archiver.ts

@@ -1,6 +1,7 @@
 import type { BlobClientInterface } from '@aztec/blob-client/client';
 import type { RollupContract } from '@aztec/ethereum/contracts';
 import type { ViemPublicClient, ViemPublicDebugClient } from '@aztec/ethereum/types';
+import { SlotNumber } from '@aztec/foundation/branded-types';
 import { Buffer32 } from '@aztec/foundation/buffer';
 import { Fr } from '@aztec/foundation/curves/bn254';
 import { EthAddress } from '@aztec/foundation/eth-address';
@@ -30,7 +31,7 @@ class NoopL1Synchronizer implements FunctionsOf<ArchiverL1Synchronizer> {
     return 0n;
   }
   getL1Timestamp(): bigint | undefined {
-    return 0n;
+    return undefined;
   }
   testEthereumNodeSynced(): Promise<void> {
     return Promise.resolve();
@@ -96,6 +97,11 @@ export class NoopL1Archiver extends Archiver {
     this.runningPromise.start();
     return Promise.resolve();
   }
+
+  /** Always reports as fully synced since there is no real L1 to sync from. */
+  public override getSyncedL2SlotNumber(): Promise<SlotNumber | undefined> {
+    return Promise.resolve(SlotNumber(Number.MAX_SAFE_INTEGER));
+  }
 }
 
 /** Creates an archiver with mocked L1 connectivity for testing. */

yarn-project/aztec-node/src/sentinel/sentinel.ts

@@ -309,9 +309,9 @@ export class Sentinel extends (EventEmitter as new () => WatcherEmitter) impleme
       return false;
     }
 
-    const archiverSlot = await this.archiver.getL2SlotNumber();
-    if (archiverSlot === undefined || archiverSlot < targetSlot) {
-      this.logger.debug(`Waiting for archiver to sync with L2 slot ${targetSlot}`, { archiverSlot, targetSlot });
+    const syncedSlot = await this.archiver.getSyncedL2SlotNumber();
+    if (syncedSlot === undefined || syncedSlot < targetSlot) {
+      this.logger.debug(`Waiting for archiver to sync with L2 slot ${targetSlot}`, { syncedSlot, targetSlot });
       return false;
     }
 

yarn-project/p2p/src/client/p2p_client.ts

@@ -679,10 +679,11 @@ export class P2PClient extends WithTracer implements P2P {
     if (oldCheckpointNumber <= CheckpointNumber.ZERO) {
       return false;
     }
-    const isEpochPrune = oldCheckpointNumber !== newCheckpoint.number;
-    this.log.info(
-      `Detected epoch prune: ${isEpochPrune}. Old checkpoint: ${oldCheckpointNumber}, new checkpoint: ${newCheckpoint.number}`,
-    );
+    const newCheckpointNumber = newCheckpoint.number;
+    const isEpochPrune = oldCheckpointNumber !== newCheckpointNumber;
+    if (isEpochPrune) {
+      this.log.info(`Detected epoch prune to ${newCheckpointNumber}`, { oldCheckpointNumber, newCheckpointNumber });
+    }
     return isEpochPrune;
   }
 

yarn-project/sequencer-client/src/sequencer/sequencer.test.ts

@@ -275,6 +275,7 @@ describe('sequencer', () => {
       getCheckpointedBlocksForEpoch: mockFn().mockResolvedValue([]),
       getCheckpointsForEpoch: mockFn().mockResolvedValue([]),
       getCheckpointsDataForEpoch: mockFn().mockResolvedValue([]),
+      getSyncedL2SlotNumber: mockFn().mockResolvedValue(SlotNumber(Number.MAX_SAFE_INTEGER)),
     });
 
     l1ToL2MessageSource = mock<L1ToL2MessageSource>({
@@ -399,14 +400,16 @@ describe('sequencer', () => {
       expectPublisherProposeL2Block();
     });
 
-    it('builds a block only when synced to previous L1 slot', async () => {
+    it('builds a block only when synced to previous L2 slot', async () => {
       await setupSingleTxBlock();
 
-      l2BlockSource.getL1Timestamp.mockResolvedValue(1000n - BigInt(ethereumSlotDuration) - 1n);
+      // Archiver reports it hasn't synced any slot yet, so sequencer should not propose
+      l2BlockSource.getSyncedL2SlotNumber.mockResolvedValue(undefined);
       await sequencer.work();
       expect(publisher.enqueueProposeCheckpoint).not.toHaveBeenCalled();
 
-      l2BlockSource.getL1Timestamp.mockResolvedValue(1000n - BigInt(ethereumSlotDuration));
+      // Archiver reports synced to slot 0, which satisfies syncedL2Slot + 1 >= slot (slot=1)
+      l2BlockSource.getSyncedL2SlotNumber.mockResolvedValue(SlotNumber(0));
       await sequencer.work();
       expect(publisher.enqueueProposeCheckpoint).toHaveBeenCalled();
     });