fix(backend): preserve request context in indexer worker and SSE timers

backend/src/services/sse.service.ts

@@ -1,5 +1,6 @@
+import { randomUUID } from 'crypto';
 import type { Response } from 'express';
-import logger from '../logger.js';
+import logger, { requestContext } from '../logger.js';
 import { isRedisAvailable, getPublisher, getSubscriber } from '../lib/redis.js';
 
 const HEARTBEAT_INTERVAL_MS = 30_000;
@@ -34,6 +35,13 @@ export class SSEService {
   private perIpPeakConnections = 0;
   private perUserPeakConnections = 0;
 
+  /**
+   * Stable id attached to every log line emitted by the heartbeat
+   * setInterval callback, since it fires outside of any HTTP request and
+   * would otherwise have no requestContext (and thus no correlation id).
+   */
+  private readonly heartbeatWorkerId = `sse-heartbeat:${randomUUID()}`;
+
   private readonly maxConnections: number = (() => {
     const parsed = Number.parseInt(process.env.MAX_SSE_CONNECTIONS ?? '10000', 10);
     if (!Number.isFinite(parsed) || parsed <= 0) return 10000;
@@ -251,7 +259,9 @@ export class SSEService {
     }
 
     this.heartbeatTimer = setInterval(() => {
-      this.sendHeartbeat();
+      requestContext.run({ requestId: this.heartbeatWorkerId }, () => {
+        this.sendHeartbeat();
+      });
     }, HEARTBEAT_INTERVAL_MS);
   }
 

backend/src/workers/soroban-event-worker.ts

@@ -1,8 +1,9 @@
+import { randomUUID } from "crypto";
 import { rpc, xdr, StrKey } from "@stellar/stellar-sdk";
 import { prisma } from "../lib/prisma.js";
 import { INDEXER_STATE_ID, ensureIndexerState } from "../lib/indexer-state.js";
 import { sseService } from "../services/sse.service.js";
-import logger from "../logger.js";
+import logger, { requestContext } from "../logger.js";
 import { Prisma } from "../generated/prisma/index.js";
 import "../lib/stream-id.js";
 
@@ -112,6 +113,13 @@ export class SorobanEventWorker {
   /** Recent attempt outcomes for sliding-window spike detection. */
   private recentOutcomes: { ok: boolean; at: number }[] = [];
 
+  /**
+   * Stable id attached to every log line emitted by the background poll
+   * loop, since these callbacks fire outside of any HTTP request and would
+   * otherwise have no requestContext (and thus no correlation id) at all.
+   */
+  private readonly workerId = `soroban-worker:${randomUUID()}`;
+
   constructor() {
     const rpcUrl =
       process.env.SOROBAN_RPC_URL ?? "https://soroban-testnet.stellar.org";