Stream delayed live feed events

services/api/src/index.ts

@@ -100,7 +100,7 @@ import {
 } from "@islandflow/types";
 import { createClient } from "redis";
 import { z } from "zod";
-import { LiveStateManager, isLiveItemFresh } from "./live";
+import { LiveStateManager, shouldFanoutLiveEvent } from "./live";
 
 const service = "api";
 const logger = createLogger({ service });
@@ -982,14 +982,7 @@ const run = async () => {
   ) => {
     const watermark = await liveState.ingest(ingestChannel, item);
 
-    if (
-      (ingestChannel === "options" ||
-        ingestChannel === "nbbo" ||
-        ingestChannel === "equities" ||
-        ingestChannel === "equity-quotes" ||
-        ingestChannel === "flow") &&
-      !isLiveItemFresh(ingestChannel, item)
-    ) {
+    if (!shouldFanoutLiveEvent(ingestChannel, item)) {
       return;
     }
 

services/api/src/live.ts

@@ -289,6 +289,8 @@ export const isLiveItemFresh = (
   return now - ts <= thresholdMs;
 };
 
+export const shouldFanoutLiveEvent = (_channel: LiveChannel, _item: unknown): boolean => true;
+
 const nextBeforeForItems = <T>(items: T[], cursorOf: (item: T) => Cursor): Cursor | null => {
   const last = items.at(-1);
   return last ? cursorOf(last) : null;

services/api/tests/live.test.ts

@@ -1,6 +1,11 @@
 import { describe, expect, it } from "bun:test";
 import type { ClickHouseClient } from "@islandflow/storage";
-import { LiveStateManager, isLiveItemFresh, resolveGenericLiveLimits } from "../src/live";
+import {
+  LiveStateManager,
+  isLiveItemFresh,
+  resolveGenericLiveLimits,
+  shouldFanoutLiveEvent
+} from "../src/live";
 
 const makeClickHouse = (): ClickHouseClient =>
   ({
@@ -567,9 +572,15 @@ describe("LiveStateManager", () => {
     expect(persisted).toHaveLength(1);
   });
 
-  it("exposes freshness helper for event fanout gating", () => {
+  it("exposes freshness helper for feed status", () => {
     expect(isLiveItemFresh("options", { ts: 1000 }, 1010)).toBe(true);
     expect(isLiveItemFresh("options", { ts: 1000 }, 20_001)).toBe(false);
     expect(isLiveItemFresh("equity-joins", { source_ts: 1 }, 1_000_000)).toBe(true);
   });
+
+  it("fans out stale live events so delayed data remains visible without refresh", () => {
+    expect(shouldFanoutLiveEvent("options", { ts: 1000 })).toBe(true);
+    expect(shouldFanoutLiveEvent("equities", { ts: 1000 })).toBe(true);
+    expect(shouldFanoutLiveEvent("flow", { source_ts: 1000 })).toBe(true);
+  });
 });