chore: Delay proof quote collection (#8967)

First sequencer in the epoch starts block building at the same time as
the prover nodes start generating quotes. If we collect quotes at the
beginning of block building, we don't give prover nodes enough time to
send the quotes. This delays collecting quotes until last minute.

yarn-project/prover-node/src/prover-node.ts

@@ -100,7 +100,7 @@ export class ProverNode implements ClaimsMonitorHandler, EpochMonitorHandler {
         await this.handleEpochCompleted(epochNumber);
       } else if (claim && claim.bondProvider.equals(this.publisher.getSenderAddress())) {
         const lastEpochProven = await this.l2BlockSource.getProvenL2EpochNumber();
-        if (!lastEpochProven || lastEpochProven < claim.epochToProve) {
+        if (lastEpochProven === undefined || lastEpochProven < claim.epochToProve) {
           await this.handleClaim(claim);
         }
       }

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

@@ -407,14 +407,6 @@ export class Sequencer {
 
     const newGlobalVariables = proposalHeader.globalVariables;
 
-    // Kick off the process of collecting and validating proof quotes here so it runs alongside block building
-    const proofQuotePromise = this.createProofClaimForPreviousEpoch(newGlobalVariables.slotNumber.toBigInt()).catch(
-      e => {
-        this.log.warn(`Failed to create proof claim quote ${e}`);
-        return undefined;
-      },
-    );
-
     this.metrics.recordNewBlock(newGlobalVariables.blockNumber.toNumber(), validTxs.length);
     const workTimer = new Timer();
     this.state = SequencerState.CREATING_BLOCK;
@@ -491,8 +483,8 @@ export class Sequencer {
     const attestations = await this.collectAttestations(block, txHashes);
     this.log.verbose('Attestations collected');
 
-    const proofQuote = await proofQuotePromise;
-
+    this.log.verbose('Collecting proof quotes');
+    const proofQuote = await this.createProofClaimForPreviousEpoch(newGlobalVariables.slotNumber.toBigInt());
     this.log.verbose(proofQuote ? `Using proof quote ${inspect(proofQuote.payload)}` : 'No proof quote available');
 
     try {
@@ -548,42 +540,47 @@ export class Sequencer {
   }
 
   protected async createProofClaimForPreviousEpoch(slotNumber: bigint): Promise<EpochProofQuote | undefined> {
-    // Find out which epoch we are currently in
-    const epochForBlock = await this.publisher.getEpochForSlotNumber(slotNumber);
-    if (epochForBlock < 1n) {
-      // It's the 0th epoch, nothing to be proven yet
-      this.log.verbose(`First epoch has no claim`);
-      return undefined;
-    }
-    const epochToProve = epochForBlock - 1n;
-    // Find out the next epoch that can be claimed
-    const canClaim = await this.publisher.nextEpochToClaim();
-    if (canClaim != epochToProve) {
-      // It's not the one we are looking to claim
-      this.log.verbose(`Unable to claim previous epoch (${canClaim} != ${epochToProve})`);
-      return undefined;
-    }
-    // Get quotes for the epoch to be proven
-    const quotes = await this.p2pClient.getEpochProofQuotes(epochToProve);
-    this.log.verbose(`Retrieved ${quotes.length} quotes, slot: ${slotNumber}, epoch to prove: ${epochToProve}`);
-    for (const quote of quotes) {
-      this.log.verbose(inspect(quote.payload));
-    }
-    // ensure these quotes are still valid for the slot and have the contract validate them
-    const validQuotesPromise = Promise.all(
-      quotes.filter(x => x.payload.validUntilSlot >= slotNumber).map(x => this.publisher.validateProofQuote(x)),
-    );
+    try {
+      // Find out which epoch we are currently in
+      const epochForBlock = await this.publisher.getEpochForSlotNumber(slotNumber);
+      if (epochForBlock < 1n) {
+        // It's the 0th epoch, nothing to be proven yet
+        this.log.verbose(`First epoch has no claim`);
+        return undefined;
+      }
+      const epochToProve = epochForBlock - 1n;
+      // Find out the next epoch that can be claimed
+      const canClaim = await this.publisher.nextEpochToClaim();
+      if (canClaim != epochToProve) {
+        // It's not the one we are looking to claim
+        this.log.verbose(`Unable to claim previous epoch (${canClaim} != ${epochToProve})`);
+        return undefined;
+      }
+      // Get quotes for the epoch to be proven
+      const quotes = await this.p2pClient.getEpochProofQuotes(epochToProve);
+      this.log.verbose(`Retrieved ${quotes.length} quotes, slot: ${slotNumber}, epoch to prove: ${epochToProve}`);
+      for (const quote of quotes) {
+        this.log.verbose(inspect(quote.payload));
+      }
+      // ensure these quotes are still valid for the slot and have the contract validate them
+      const validQuotesPromise = Promise.all(
+        quotes.filter(x => x.payload.validUntilSlot >= slotNumber).map(x => this.publisher.validateProofQuote(x)),
+      );
 
-    const validQuotes = (await validQuotesPromise).filter((q): q is EpochProofQuote => !!q);
-    if (!validQuotes.length) {
-      this.log.verbose(`Failed to find any valid proof quotes`);
+      const validQuotes = (await validQuotesPromise).filter((q): q is EpochProofQuote => !!q);
+      if (!validQuotes.length) {
+        this.log.verbose(`Failed to find any valid proof quotes`);
+        return undefined;
+      }
+      // pick the quote with the lowest fee
+      const sortedQuotes = validQuotes.sort(
+        (a: EpochProofQuote, b: EpochProofQuote) => a.payload.basisPointFee - b.payload.basisPointFee,
+      );
+      return sortedQuotes[0];
+    } catch (err) {
+      this.log.error(`Failed to create proof claim for previous epoch: ${err}`);
       return undefined;
     }
-    // pick the quote with the lowest fee
-    const sortedQuotes = validQuotes.sort(
-      (a: EpochProofQuote, b: EpochProofQuote) => a.payload.basisPointFee - b.payload.basisPointFee,
-    );
-    return sortedQuotes[0];
   }
 
   /**