feat(archiver): decouple calldata from blob fetching in L1 synchronizer

yarn-project/archiver/src/config.ts

@@ -57,6 +57,10 @@ export const archiverConfigMappings: ConfigMappingsType<ArchiverConfig> = {
     description: 'Skip validating checkpoint attestations (for testing purposes only)',
     ...booleanConfigHelper(false),
   },
+  skipPromoteProposedCheckpointDuringL1Sync: {
+    description: 'Skip promoting proposed checkpoints during L1 sync (for testing purposes only)',
+    ...booleanConfigHelper(false),
+  },
   maxAllowedEthClientDriftSeconds: {
     env: 'MAX_ALLOWED_ETH_CLIENT_DRIFT_SECONDS',
     description: 'Maximum allowed drift in seconds between the Ethereum client and current time.',
@@ -103,6 +107,7 @@ export function mapArchiverConfig(config: Partial<ArchiverConfig>) {
     pollingIntervalMs: config.archiverPollingIntervalMS,
     batchSize: config.archiverBatchSize,
     skipValidateCheckpointAttestations: config.skipValidateCheckpointAttestations,
+    skipPromoteProposedCheckpointDuringL1Sync: config.skipPromoteProposedCheckpointDuringL1Sync,
     maxAllowedEthClientDriftSeconds: config.maxAllowedEthClientDriftSeconds,
     ethereumAllowNoDebugHosts: config.ethereumAllowNoDebugHosts,
     skipHistoricalLogsCheck: config.archiverSkipHistoricalLogsCheck,

yarn-project/archiver/src/errors.ts

@@ -132,6 +132,40 @@ export class ProposedCheckpointNotSequentialError extends Error {
   }
 }
 
+/** Thrown when attempting to promote a proposed checkpoint but no proposed checkpoint exists in the store. */
+export class NoProposedCheckpointToPromoteError extends Error {
+  constructor() {
+    super('Cannot promote proposed checkpoint: no proposed checkpoint exists');
+    this.name = 'NoProposedCheckpointToPromoteError';
+  }
+}
+
+/** Thrown when the archive root of the proposed checkpoint does not match the expected one. */
+export class ProposedCheckpointArchiveRootMismatchError extends Error {
+  constructor(
+    public readonly expectedArchiveRoot: Fr,
+    public readonly actualArchiveRoot: Fr,
+  ) {
+    super(
+      `Cannot promote proposed checkpoint: archive root mismatch (expected ${expectedArchiveRoot}, got ${actualArchiveRoot})`,
+    );
+    this.name = 'ProposedCheckpointArchiveRootMismatchError';
+  }
+}
+
+/** Thrown when the proposed checkpoint does not directly follow the latest confirmed checkpoint. */
+export class ProposedCheckpointPromotionNotSequentialError extends Error {
+  constructor(
+    public readonly proposedCheckpointNumber: number,
+    public readonly latestCheckpointNumber: number,
+  ) {
+    super(
+      `Cannot promote proposed checkpoint: not sequential (latest ${latestCheckpointNumber}, proposed ${proposedCheckpointNumber})`,
+    );
+    this.name = 'ProposedCheckpointPromotionNotSequentialError';
+  }
+}
+
 /** Thrown when a proposed block conflicts with an already checkpointed block (different content). */
 export class CannotOverwriteCheckpointedBlockError extends Error {
   constructor(

yarn-project/archiver/src/index.ts

@@ -10,5 +10,5 @@ export { KVArchiverDataStore, ARCHIVER_DB_VERSION } from './store/kv_archiver_st
 export { ContractInstanceStore } from './store/contract_instance_store.js';
 export { L2TipsCache } from './store/l2_tips_cache.js';
 
-export { retrieveCheckpointsFromRollup, retrieveL2ProofVerifiedEvents } from './l1/data_retrieval.js';
+export { retrieveL2ProofVerifiedEvents } from './l1/data_retrieval.js';
 export { CalldataRetriever } from './l1/calldata_retriever.js';

yarn-project/archiver/src/l1/data_retrieval.ts

@@ -35,18 +35,28 @@ import type { DataRetrieval } from '../structs/data_retrieval.js';
 import type { InboxMessage } from '../structs/inbox_message.js';
 import { CalldataRetriever } from './calldata_retriever.js';
 
-export type RetrievedCheckpoint = {
+type RetrievedCheckpointBase = {
   checkpointNumber: CheckpointNumber;
   archiveRoot: Fr;
   feeAssetPriceModifier: bigint;
   header: CheckpointHeader;
-  checkpointBlobData: CheckpointBlobData;
   l1: L1PublishedData;
   chainId: Fr;
   version: Fr;
   attestations: CommitteeAttestation[];
 };
 
+/** Checkpoint data as retrieved from L1 calldata and blob data. */
+export type RetrievedCheckpoint = RetrievedCheckpointBase & { checkpointBlobData: CheckpointBlobData };
+
+/** Checkpoint data retrieved from L1 calldata only, without blob data. */
+export type RetrievedCheckpointFromCalldata = RetrievedCheckpointBase & {
+  /** Versioned blob hashes from the checkpoint proposed event. */
+  blobHashes: Buffer[];
+  /** Parent beacon block root from the L1 block, used for blob fetching. */
+  parentBeaconBlockRoot: string | undefined;
+};
+
 export async function retrievedToPublishedCheckpoint({
   checkpointNumber,
   archiveRoot,
@@ -137,31 +147,27 @@ export async function retrievedToPublishedCheckpoint({
 }
 
 /**
- * Fetches new checkpoints.
+ * Fetches checkpoint calldata from the rollup contract without fetching blob data.
+ * Returns RetrievedCheckpointFromCalldata objects that preserve the information needed for deferred blob fetching.
  * @param rollup - The rollup contract wrapper.
  * @param publicClient - The viem public client to use for transaction retrieval.
  * @param debugClient - The viem debug client to use for trace/debug RPC methods (optional).
- * @param blobClient - The blob client client for fetching blob data.
  * @param searchStartBlock - The block number to use for starting the search.
  * @param searchEndBlock - The highest block number that we should search up to.
- * @param contractAddresses - The contract addresses (governanceProposerAddress, slashingProposerAddress).
  * @param instrumentation - The archiver instrumentation instance.
  * @param logger - The logger instance.
- * @param isHistoricalSync - Whether this is a historical sync.
- * @returns An array of retrieved checkpoints.
+ * @returns An array of calldata-only checkpoints.
  */
-export async function retrieveCheckpointsFromRollup(
+export async function retrieveCheckpointCalldataFromRollup(
   rollup: RollupContract,
   publicClient: ViemPublicClient,
   debugClient: ViemPublicDebugClient,
-  blobClient: BlobClientInterface,
   searchStartBlock: bigint,
   searchEndBlock: bigint,
   instrumentation: ArchiverInstrumentation,
   logger: Logger = createLogger('archiver'),
-  isHistoricalSync: boolean = false,
-): Promise<RetrievedCheckpoint[]> {
-  const retrievedCheckpoints: RetrievedCheckpoint[] = [];
+): Promise<RetrievedCheckpointFromCalldata[]> {
+  const retrievedCheckpoints: RetrievedCheckpointFromCalldata[] = [];
 
   let rollupConstants: { chainId: Fr; version: Fr; targetCommitteeSize: number } | undefined;
 
@@ -197,46 +203,39 @@ export async function retrieveCheckpointsFromRollup(
       rollup,
       publicClient,
       debugClient,
-      blobClient,
       checkpointProposedLogs,
       rollupConstants,
       instrumentation,
       logger,
-      isHistoricalSync,
     );
     retrievedCheckpoints.push(...newCheckpoints);
     searchStartBlock = lastLog.l1BlockNumber + 1n;
   } while (searchStartBlock <= searchEndBlock);
 
-  // The asyncPool from processCheckpointProposedLogs will not necessarily return the checkpoints in order, so we sort them before returning.
   return retrievedCheckpoints.sort((a, b) => Number(a.l1.blockNumber - b.l1.blockNumber));
 }
 
 /**
- * Processes newly received CheckpointProposed logs.
+ * Processes CheckpointProposed logs, fetching only calldata (no blobs).
  * @param rollup - The rollup contract wrapper.
  * @param publicClient - The viem public client to use for transaction retrieval.
  * @param debugClient - The viem debug client to use for trace/debug RPC methods (optional).
- * @param blobClient - The blob client client for fetching blob data.
  * @param logs - CheckpointProposed logs.
  * @param rollupConstants - The rollup constants (chainId, version, targetCommitteeSize).
  * @param instrumentation - The archiver instrumentation instance.
  * @param logger - The logger instance.
- * @param isHistoricalSync - Whether this is a historical sync.
- * @returns An array of retrieved checkpoints.
+ * @returns An array of calldata-only checkpoints.
  */
 async function processCheckpointProposedLogs(
   rollup: RollupContract,
   publicClient: ViemPublicClient,
   debugClient: ViemPublicDebugClient,
-  blobClient: BlobClientInterface,
   logs: CheckpointProposedLog[],
   { chainId, version, targetCommitteeSize }: { chainId: Fr; version: Fr; targetCommitteeSize: number },
   instrumentation: ArchiverInstrumentation,
   logger: Logger,
-  isHistoricalSync: boolean,
-): Promise<RetrievedCheckpoint[]> {
-  const retrievedCheckpoints: RetrievedCheckpoint[] = [];
+): Promise<RetrievedCheckpointFromCalldata[]> {
+  const retrievedCheckpoints: RetrievedCheckpointFromCalldata[] = [];
   const calldataRetriever = new CalldataRetriever(
     publicClient,
     debugClient,
@@ -252,7 +251,6 @@ async function processCheckpointProposedLogs(
     const archiveFromChain = await rollup.archiveAt(checkpointNumber);
     const blobHashes = log.args.versionedBlobHashes;
 
-    // The value from the event and contract will match only if the checkpoint is in the chain.
     if (archive.equals(archiveFromChain)) {
       const expectedHashes = {
         attestationsHash: log.args.attestationsHash.toString() as Hex,
@@ -268,19 +266,16 @@ async function processCheckpointProposedLogs(
       const { timestamp, parentBeaconBlockRoot } = await getL1Block(publicClient, log.l1BlockNumber);
       const l1 = new L1PublishedData(log.l1BlockNumber, timestamp, log.l1BlockHash.toString());
 
-      const checkpointBlobData = await getCheckpointBlobDataFromBlobs(
-        blobClient,
-        checkpoint.blockHash,
+      retrievedCheckpoints.push({
+        ...checkpoint,
+        l1,
+        chainId,
+        version,
         blobHashes,
-        checkpointNumber,
-        logger,
-        isHistoricalSync,
         parentBeaconBlockRoot,
-        timestamp,
-      );
+      });
 
-      retrievedCheckpoints.push({ ...checkpoint, checkpointBlobData, l1, chainId, version });
-      logger.trace(`Retrieved checkpoint ${checkpointNumber} from L1 tx ${log.l1TransactionHash}`, {
+      logger.trace(`Retrieved checkpoint calldata ${checkpointNumber} from L1 tx ${log.l1TransactionHash}`, {
         l1BlockNumber: log.l1BlockNumber,
         checkpointNumber,
         archive: archive.toString(),

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

@@ -6,8 +6,13 @@ import {
   ContractInstancePublishedEvent,
   ContractInstanceUpdatedEvent,
 } from '@aztec/protocol-contracts/instance-registry';
-import type { L2Block, ValidateCheckpointResult } from '@aztec/stdlib/block';
-import { type ProposedCheckpointInput, type PublishedCheckpoint, validateCheckpoint } from '@aztec/stdlib/checkpoint';
+import type { CommitteeAttestation, L2Block, ValidateCheckpointResult } from '@aztec/stdlib/block';
+import {
+  type L1PublishedData,
+  type ProposedCheckpointInput,
+  type PublishedCheckpoint,
+  validateCheckpoint,
+} from '@aztec/stdlib/checkpoint';
 import {
   type ContractClassPublicWithCommitment,
   computeContractAddressFromInstance,
@@ -79,18 +84,29 @@ export class ArchiverDataStoreUpdater {
    * Adds new checkpoints to the store with contract class/instance extraction from logs.
    * Prunes any local blocks that conflict with checkpoint data (by comparing archive roots).
    * Extracts ContractClassPublished, ContractInstancePublished, ContractInstanceUpdated events from the checkpoint block logs.
+   * If `promoteProposed` is supplied, the proposed-checkpoint promotion runs inside the same transaction
+   * as the added checkpoints so both updates are applied atomically.
    *
-   * @param checkpoints - The published checkpoints to add.
+   * @param checkpoints - The published checkpoints to add (excluding any being promoted from proposed).
    * @param pendingChainValidationStatus - Optional validation status to set.
+   * @param promoteProposed - Optional promotion of the current proposed checkpoint (fast path when blocks are already local).
    * @returns Result with information about any pruned blocks.
    */
   public async addCheckpoints(
     checkpoints: PublishedCheckpoint[],
     pendingChainValidationStatus?: ValidateCheckpointResult,
+    promoteProposed?: {
+      l1: L1PublishedData;
+      attestations: CommitteeAttestation[];
+      checkpoint: PublishedCheckpoint;
+    },
   ): Promise<ReconcileCheckpointsResult> {
     for (const checkpoint of checkpoints) {
       validateCheckpoint(checkpoint.checkpoint, { rollupManaLimit: this.opts?.rollupManaLimit });
     }
+    if (promoteProposed) {
+      validateCheckpoint(promoteProposed.checkpoint.checkpoint, { rollupManaLimit: this.opts?.rollupManaLimit });
+    }
 
     const result = await this.store.transactionAsync(async () => {
       // Before adding checkpoints, check for conflicts with local blocks if any
@@ -110,6 +126,14 @@ export class ArchiverDataStoreUpdater {
         this.store.addLogs(newBlocks),
         // Unroll all logs emitted during the retrieved blocks and extract any contract classes and instances from them
         ...newBlocks.map(block => this.addContractDataToDb(block)),
+        // Promote the proposed checkpoint if requested
+        promoteProposed
+          ? this.store.promoteProposedToCheckpointed(
+              promoteProposed.l1,
+              promoteProposed.attestations,
+              promoteProposed.checkpoint.checkpoint.archive.root,
+            )
+          : undefined,
       ]);
 
       await this.l2TipsCache?.refresh();

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

@@ -43,6 +43,7 @@ export class ArchiverInstrumentation {
   private blockProposalTxTargetCount: UpDownCounter;
 
   private checkpointL1InclusionDelay: Histogram;
+  private checkpointPromotedCount: UpDownCounter;
 
   private log = createLogger('archiver:instrumentation');
 
@@ -95,6 +96,8 @@ export class ArchiverInstrumentation {
 
     this.checkpointL1InclusionDelay = meter.createHistogram(Metrics.ARCHIVER_CHECKPOINT_L1_INCLUSION_DELAY);
 
+    this.checkpointPromotedCount = createUpDownCounterWithDefault(meter, Metrics.ARCHIVER_CHECKPOINT_PROMOTED_COUNT);
+
     this.dbMetrics = new LmdbMetrics(
       meter,
       {
@@ -181,6 +184,11 @@ export class ArchiverInstrumentation {
     });
   }
 
+  /** Records a checkpoint promoted from proposed (blob fetch skipped). */
+  public processCheckpointPromoted() {
+    this.checkpointPromotedCount.add(1);
+  }
+
   /**
    * Records L1 inclusion timing for a checkpoint observed on L1 (seconds into the L2 slot).
    */