feat(go): add 100k ingest hardening baseline

go/vehicle-gateway/cmd/realtime-api/main_test.go

@@ -134,6 +134,35 @@ func TestAsyncSecondaryRealtimeUpdaterDoesNotBlockPrimaryPath(t *testing.T) {
 	}
 }
 
+func TestAsyncSecondaryQueueDropDoesNotFailPrimaryUpdate(t *testing.T) {
+	env := envelope.FrameEnvelope{Protocol: envelope.ProtocolJT808, VIN: "VIN001"}
+	primary := &contextCheckingRealtimeUpdater{}
+	registry := metrics.NewRegistry()
+	updater := &asyncSecondaryRealtimeUpdater{
+		primary:   primary,
+		secondary: &contextCheckingRealtimeUpdater{},
+		queue:     make(chan envelope.FrameEnvelope, 1),
+		registry:  registry,
+	}
+	updater.queue <- envelope.FrameEnvelope{Protocol: envelope.ProtocolJT808, VIN: "VIN000"}
+
+	if err := updater.Update(context.Background(), env); err != nil {
+		t.Fatalf("Update() error = %v", err)
+	}
+	if primary.count != 1 {
+		t.Fatalf("primary updates = %d, want 1", primary.count)
+	}
+	text := registry.Render()
+	for _, want := range []string{
+		`vehicle_realtime_async_queue_total{protocol="JT808",status="dropped",store="mysql"} 1`,
+		`vehicle_realtime_async_queue_depth{protocol="JT808",store="mysql"} 1`,
+	} {
+		if !strings.Contains(text, want) {
+			t.Fatalf("async queue drop metric missing %s:\n%s", want, text)
+		}
+	}
+}
+
 func TestStoreMetricUpdaterRecordsStoreUpdateResults(t *testing.T) {
 	registry := metrics.NewRegistry()
 	env := envelope.FrameEnvelope{Protocol: envelope.ProtocolJT808, VIN: "VIN001"}