refactor: clean up code (#5308)

pkg/metrics/mem/server_test.go

@@ -0,0 +1,83 @@
+package mem
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+	clocktesting "k8s.io/utils/clock/testing"
+)
+
+func TestServerMetricsUsesClockForProxyTimestamps(t *testing.T) {
+	require := require.New(t)
+
+	start := time.Date(2026, time.May, 8, 12, 30, 0, 0, time.UTC)
+	clk := clocktesting.NewFakeClock(start)
+	metrics := newServerMetricsWithClock(clk)
+
+	metrics.NewProxy("proxy", "tcp", "user", "client-id")
+	require.Equal(start, metrics.info.ProxyStatistics["proxy"].LastStartTime)
+
+	closedAt := start.Add(time.Minute)
+	clk.SetTime(closedAt)
+	metrics.CloseProxy("proxy", "tcp")
+	require.Equal(closedAt, metrics.info.ProxyStatistics["proxy"].LastCloseTime)
+}
+
+func TestServerMetricsClearUselessInfoUsesClock(t *testing.T) {
+	require := require.New(t)
+
+	start := time.Date(2026, time.May, 8, 12, 30, 0, 0, time.UTC)
+	clk := clocktesting.NewFakeClock(start.Add(25 * time.Hour))
+	metrics := newServerMetricsWithClock(clk)
+	metrics.info.ProxyStatistics["proxy"] = &ProxyStatistics{
+		Name:          "proxy",
+		LastStartTime: start.Add(-time.Hour),
+		LastCloseTime: start,
+	}
+
+	count, total := metrics.clearUselessInfo(24 * time.Hour)
+
+	require.Equal(1, count)
+	require.Equal(1, total)
+	require.Empty(metrics.info.ProxyStatistics)
+}
+
+func TestServerMetricsRunUsesClockTicker(t *testing.T) {
+	require := require.New(t)
+
+	start := time.Date(2026, time.May, 8, 12, 30, 0, 0, time.UTC)
+	clk := clocktesting.NewFakeClock(start)
+	metrics := newServerMetricsWithClock(clk)
+	metrics.info.ProxyStatistics["proxy"] = &ProxyStatistics{
+		Name:          "proxy",
+		LastStartTime: start.Add(-time.Hour),
+		LastCloseTime: start,
+	}
+
+	stopCh := make(chan struct{})
+	done := make(chan struct{})
+	go func() {
+		defer close(done)
+		metrics.runUntil(stopCh)
+	}()
+	t.Cleanup(func() {
+		close(stopCh)
+		<-done
+	})
+
+	require.Eventually(clk.HasWaiters, time.Second, time.Millisecond)
+	clk.Step(8 * 24 * time.Hour)
+
+	require.Eventually(func() bool {
+		return !metrics.hasProxyStatistics("proxy")
+	}, time.Second, time.Millisecond)
+}
+
+func (m *serverMetrics) hasProxyStatistics(name string) bool {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	_, ok := m.info.ProxyStatistics[name]
+	return ok
+}