Expose Arena ELO sync in feature flags (#3821)

Adds ARENA_ELO_SYNC_ENABLED to the Dashboard Feature Flags registry (DB-overridable),
routes Arena ELO startup/status checks through the shared feature-flag resolver while
preserving the existing env fallback, and refreshes env docs (adds the missing
STREAM_READINESS_TIMEOUT_MS example) so env/doc sync stays green.

Integrated into release/v3.8.25.

Co-authored-by: R.D. <rogerproself@gmail.com>

tests/integration/integration-wiring.test.ts

@@ -88,9 +88,10 @@ describe("Pipeline Wiring — instrumentation-node.ts", () => {
   it("should initialize Arena ELO sync on the live startup path (on by default, opt-out)", () => {
     // The Next standalone runtime boots through instrumentation-node, NOT server-init.ts.
     // The Arena ELO sync (which feeds the Free Provider Rankings page) must be wired here,
-    // or it never runs in production regardless of ARENA_ELO_SYNC_ENABLED.
+    // or it never runs in production. initArenaEloSync self-gates through the feature flag
+    // resolver so ARENA_ELO_SYNC_ENABLED and dashboard overrides still apply.
     assert.match(src, /initArenaEloSync/);
-    assert.match(src, /ARENA_ELO_SYNC_ENABLED !== "false"/);
+    assert.match(src, /const started = await initArenaEloSync\(\)/);
   });
 
   it("should initialize pricing + models.dev sync on the live startup path (self-gated, opt-in)", () => {

tests/unit/arena-elo-sync.test.ts

@@ -35,8 +35,11 @@ const {
   fetchArenaLeaderboards,
   syncArenaElo,
   getArenaEloSyncStatus,
+  initArenaEloSync,
   stopArenaEloSync,
 } = await import("../../src/lib/arenaEloSync.ts");
+const { setFeatureFlagOverride, removeFeatureFlagOverride } =
+  await import("../../src/lib/db/featureFlags.ts");
 
 import type {
   ArenaLeaderboardData,
@@ -102,6 +105,14 @@ function createTestAdapter(): SqliteAdapter {
     "\n  synced_at TEXT NOT NULL"
   );
   const adapter = tryOpenSync(":memory:")!;
+  adapter.exec(`
+    CREATE TABLE IF NOT EXISTS key_value (
+      namespace TEXT NOT NULL,
+      key TEXT NOT NULL,
+      value TEXT NOT NULL,
+      PRIMARY KEY (namespace, key)
+    );
+  `);
   adapter.exec(patchedSql);
   return adapter;
 }
@@ -124,12 +135,14 @@ beforeEach(() => {
   testAdapter = createTestAdapter();
   globalThis.__omnirouteDb = testAdapter as never;
   stopArenaEloSync();
+  delete process.env.ARENA_ELO_SYNC_ENABLED;
 });
 
 afterEach(() => {
   restoreFetch();
   stopArenaEloSync();
   delete globalThis.__omnirouteDb;
+  delete process.env.ARENA_ELO_SYNC_ENABLED;
 });
 
 // ═══════════════════════════════════════════════════════════
@@ -767,6 +780,26 @@ describe("getArenaEloSyncStatus()", () => {
       delete process.env.ARENA_ELO_SYNC_ENABLED;
     }
   });
+
+  it("reflects dashboard feature flag DB overrides before env values", () => {
+    process.env.ARENA_ELO_SYNC_ENABLED = "true";
+    try {
+      setFeatureFlagOverride("ARENA_ELO_SYNC_ENABLED", "false");
+
+      const status = getArenaEloSyncStatus();
+      assert.strictEqual(status.enabled, false);
+    } finally {
+      removeFeatureFlagOverride("ARENA_ELO_SYNC_ENABLED");
+    }
+  });
+
+  it("falls back to the env value if the feature flag store is unavailable", () => {
+    testAdapter.exec("DROP TABLE key_value");
+    process.env.ARENA_ELO_SYNC_ENABLED = "false";
+
+    const status = getArenaEloSyncStatus();
+    assert.strictEqual(status.enabled, false);
+  });
 });
 
 // ═══════════════════════════════════════════════════════════
@@ -774,6 +807,16 @@ describe("getArenaEloSyncStatus()", () => {
 // ═══════════════════════════════════════════════════════════
 
 describe("stopArenaEloSync()", () => {
+  it("initArenaEloSync returns false when disabled by feature flag", async () => {
+    try {
+      setFeatureFlagOverride("ARENA_ELO_SYNC_ENABLED", "false");
+      const started = await initArenaEloSync();
+      assert.strictEqual(started, false);
+    } finally {
+      removeFeatureFlagOverride("ARENA_ELO_SYNC_ENABLED");
+    }
+  });
+
   it("does not throw when no timer is running", () => {
     assert.doesNotThrow(() => stopArenaEloSync());
   });

tests/unit/feature-flags-settings.test.ts

@@ -26,19 +26,20 @@ const {
   isRequireApiKeyEnabled,
   isCcCompatibleProviderEnabled,
   isModelCatalogNamesEnabled,
+  isArenaEloSyncEnabled,
 } = await import("../../src/shared/utils/featureFlags.ts");
 
 // ──────────────────────────────────────────────────────
 // Test group 1 — Flag definitions registry
 // ──────────────────────────────────────────────────────
 describe("featureFlagDefinitions", () => {
-  it("has exactly 31 flag definitions", () => {
-    assert.strictEqual(FEATURE_FLAG_DEFINITIONS.length, 31);
+  it("has exactly 32 flag definitions", () => {
+    assert.strictEqual(FEATURE_FLAG_DEFINITIONS.length, 32);
   });
 
   it("has unique keys for all flags", () => {
     const keys = FEATURE_FLAG_DEFINITIONS.map((d) => d.key);
-    assert.strictEqual(new Set(keys).size, 31);
+    assert.strictEqual(new Set(keys).size, 32);
   });
 
   it("has valid categories for all flags", () => {
@@ -96,6 +97,15 @@ describe("featureFlagDefinitions", () => {
     assert.strictEqual(def.requiresRestart, false);
   });
 
+  it("defines Arena ELO sync as a runtime boolean flag enabled by default", () => {
+    const def = FEATURE_FLAG_DEFINITIONS.find((d) => d.key === "ARENA_ELO_SYNC_ENABLED");
+    assert.ok(def, "ARENA_ELO_SYNC_ENABLED should exist");
+    assert.strictEqual(def.category, "runtime");
+    assert.strictEqual(def.type, "boolean");
+    assert.strictEqual(def.defaultValue, "true");
+    assert.strictEqual(def.requiresRestart, false);
+  });
+
   it("defines emergency fallback as a runtime boolean flag enabled by default", () => {
     const def = FEATURE_FLAG_DEFINITIONS.find((d) => d.key === "OMNIROUTE_EMERGENCY_FALLBACK");
     assert.ok(def, "OMNIROUTE_EMERGENCY_FALLBACK should exist");
@@ -241,9 +251,9 @@ describe("resolveFeatureFlag", () => {
   });
 
   describe("resolveAllFeatureFlags", () => {
-    it("returns all 31 flags", () => {
+    it("returns all 32 flags", () => {
       const all = resolveAllFeatureFlags();
-      assert.strictEqual(all.length, 31);
+      assert.strictEqual(all.length, 32);
     });
 
     it("marks DB-overridden flags with source 'db'", () => {
@@ -306,6 +316,16 @@ describe("resolveFeatureFlag", () => {
         removeFeatureFlagOverride("MODEL_CATALOG_INCLUDE_NAMES");
       }
     });
+
+    it("isArenaEloSyncEnabled defaults on and follows DB overrides", () => {
+      assert.strictEqual(isArenaEloSyncEnabled(), true);
+      try {
+        setFeatureFlagOverride("ARENA_ELO_SYNC_ENABLED", "false");
+        assert.strictEqual(isArenaEloSyncEnabled(), false);
+      } finally {
+        removeFeatureFlagOverride("ARENA_ELO_SYNC_ENABLED");
+      }
+    });
   });
 });