refactor(pxe): batch log RPC calls in LogService.fetchLogsByTag

yarn-project/pxe/src/logs/log_service.test.ts

@@ -146,5 +146,40 @@ describe('LogService', () => {
         /Got a log retrieval request from/,
       );
     });
+
+    it('batches multiple requests into single RPC calls', async () => {
+      const tag1 = Tag.random();
+      const tag2 = Tag.random();
+      const tag3 = Tag.random();
+
+      const publicLog1 = randomTxScopedPrivateL2Log();
+      const privateLog2 = randomTxScopedPrivateL2Log();
+
+      aztecNode.getPublicLogsByTagsFromContract.mockResolvedValue([[publicLog1], [], []]);
+      aztecNode.getPrivateLogsByTags.mockResolvedValue([[], [privateLog2], []]);
+
+      const requests = [
+        new LogRetrievalRequest(contractAddress, tag1),
+        new LogRetrievalRequest(contractAddress, tag2),
+        new LogRetrievalRequest(contractAddress, tag3),
+      ];
+
+      const responses = await logService.fetchLogsByTag(contractAddress, requests);
+
+      expect(responses).toHaveLength(3);
+      expect(responses[0]).toEqual(expect.objectContaining({ txHash: publicLog1.txHash }));
+      expect(responses[1]).toEqual(expect.objectContaining({ txHash: privateLog2.txHash }));
+      expect(responses[2]).toBeNull();
+
+      expect(aztecNode.getPublicLogsByTagsFromContract).toHaveBeenCalledTimes(1);
+      expect(aztecNode.getPrivateLogsByTags).toHaveBeenCalledTimes(1);
+    });
+
+    it('returns empty array for empty requests', async () => {
+      const responses = await logService.fetchLogsByTag(contractAddress, []);
+      expect(responses).toEqual([]);
+      expect(aztecNode.getPublicLogsByTagsFromContract).not.toHaveBeenCalled();
+      expect(aztecNode.getPrivateLogsByTags).not.toHaveBeenCalled();
+    });
   });
 });

yarn-project/pxe/src/logs/log_service.ts

@@ -3,7 +3,12 @@ import type { KeyStore } from '@aztec/key-store';
 import { AztecAddress } from '@aztec/stdlib/aztec-address';
 import type { L2TipsProvider } from '@aztec/stdlib/block';
 import type { AztecNode } from '@aztec/stdlib/interfaces/server';
-import { ExtendedDirectionalAppTaggingSecret, PendingTaggedLog, SiloedTag, Tag } from '@aztec/stdlib/logs';
+import {
+  ExtendedDirectionalAppTaggingSecret,
+  PendingTaggedLog,
+  SiloedTag,
+  type TxScopedL2Log,
+} from '@aztec/stdlib/logs';
 import type { BlockHeader } from '@aztec/stdlib/tx';
 
 import type { LogRetrievalRequest } from '../contract_function_simulator/noir-structs/log_retrieval_request.js';
@@ -44,62 +49,46 @@ export class LogService {
       }
     }
 
-    return await Promise.all(
-      logRetrievalRequests.map(async request => {
-        const [publicLog, privateLog] = await Promise.all([
-          this.#getPublicLogByTag(request.tag, request.contractAddress),
-          this.#getPrivateLogByTag(await SiloedTag.computeFromTagAndApp(request.tag, request.contractAddress)),
-        ]);
-
-        if (publicLog !== null && privateLog !== null) {
-          this.log.warn(
-            `Found both a public and private log for tag ${request.tag} from contract ${request.contractAddress}. This may indicate a contract bug. Returning the public log.`,
-          );
-        }
-
-        return publicLog ?? privateLog;
-      }),
-    );
-  }
+    if (logRetrievalRequests.length === 0) {
+      return [];
+    }
 
-  async #getPublicLogByTag(tag: Tag, contractAddress: AztecAddress): Promise<LogRetrievalResponse | null> {
     const anchorBlockHash = await this.anchorBlockHeader.hash();
-    const allLogsPerTag = await getAllPublicLogsByTagsFromContract(
-      this.aztecNode,
-      contractAddress,
-      [tag],
-      anchorBlockHash,
+    const tags = logRetrievalRequests.map(r => r.tag);
+    const siloedTags = await Promise.all(
+      logRetrievalRequests.map(r => SiloedTag.computeFromTagAndApp(r.tag, r.contractAddress)),
     );
-    const logsForTag = allLogsPerTag[0];
 
-    if (logsForTag.length === 0) {
-      return null;
-    } else if (logsForTag.length > 1) {
-      this.log.warn(
-        `Expected at most 1 public log for tag ${tag} and contract ${contractAddress.toString()}, got ${logsForTag.length}. This may indicate a contract bug. Returning the first log.`,
+    const [allPublicLogsPerTag, allPrivateLogsPerTag] = await Promise.all([
+      getAllPublicLogsByTagsFromContract(this.aztecNode, contractAddress, tags, anchorBlockHash),
+      getAllPrivateLogsByTags(this.aztecNode, siloedTags, anchorBlockHash),
+    ]);
+
+    return logRetrievalRequests.map((request, i) => {
+      const publicLog = this.#extractSingleLog(
+        allPublicLogsPerTag[i],
+        `public log for tag ${request.tag} and contract ${request.contractAddress.toString()}`,
       );
-    }
+      const privateLog = this.#extractSingleLog(allPrivateLogsPerTag[i], `private log for tag ${siloedTags[i]}`);
 
-    const scopedLog = logsForTag[0];
+      if (publicLog !== null && privateLog !== null) {
+        this.log.warn(
+          `Found both a public and private log for tag ${request.tag} from contract ${request.contractAddress}. This may indicate a contract bug. Returning the public log.`,
+        );
+      }
 
-    return new LogRetrievalResponse(
-      scopedLog.logData.slice(1), // Skip the tag
-      scopedLog.txHash,
-      scopedLog.noteHashes,
-      scopedLog.firstNullifier,
-    );
+      return publicLog ?? privateLog;
+    });
   }
 
-  async #getPrivateLogByTag(siloedTag: SiloedTag): Promise<LogRetrievalResponse | null> {
-    const anchorBlockHash = await this.anchorBlockHeader.hash();
-    const allLogsPerTag = await getAllPrivateLogsByTags(this.aztecNode, [siloedTag], anchorBlockHash);
-    const logsForTag = allLogsPerTag[0];
-
+  #extractSingleLog(logsForTag: TxScopedL2Log[], description: string): LogRetrievalResponse | null {
     if (logsForTag.length === 0) {
       return null;
-    } else if (logsForTag.length > 1) {
+    }
+
+    if (logsForTag.length > 1) {
       this.log.warn(
-        `Expected at most 1 private log for tag ${siloedTag}, got ${logsForTag.length}. This may indicate a contract bug. Returning the first log.`,
+        `Expected at most 1 ${description}, got ${logsForTag.length}. This may indicate a contract bug. Returning the first log.`,
       );
     }