P8(1): restore homepage overview curves on a memory-only sampling ring

Backend: new overviewMetrics store — a single-tier (2s x 360 = 12min) in-memory ring fed by ServerService.RefreshStatus for exactly the eight overview series (cpu/mem/swap/diskUsage/netUp/netDown/tcpCount/udpCount). No persistence, no gob snapshot, no system-history page: the only surface is GET /panel/api/server/history/:metric/:bucket restricted to those keys, which seeds the frontend curves. ~46KB bounded by construction; the ring starts empty on every panel start. Frontend: restore useOverviewHistory + the VitalTile/ThroughputCard/ ConnectionsCard sparklines and the IndexPage wiring exactly as they were before P7 removed them along with the history module.
2026-10-21 13:49:43 +00:00
parent 60ce5eab98
commit 261a1f6787
9 changed files with 483 additions and 26 deletions
@@ -0,0 +1,67 @@
+package service
+
+import (
+	"testing"
+	"time"
+)
+
+// The overview ring is a fresh store per test (the package singleton is fed
+// by RefreshStatus in production); these tests pin its contract: only the
+// overview keys are written by AppendOverviewSample, samples come back
+// through AggregateOverviewMetric, and the window is hard-bounded by the
+// single tier's capacity no matter how long the panel runs.
+
+func overviewTestStatus(cpu float64) *Status {
+	st := &Status{Cpu: cpu, TcpCount: 3, UdpCount: 2}
+	st.Mem.Current = 1
+	st.Mem.Total = 4
+	st.Swap.Current = 0
+	st.Swap.Total = 0
+	st.Disk.Current = 1
+	st.Disk.Total = 2
+	st.NetIO.Up = 100
+	st.NetIO.Down = 200
+	return st
+}
+
+func TestOverviewRingAppendAndAggregate(t *testing.T) {
+	s := &ServerService{}
+	base := time.Now().Add(-10 * time.Second).Truncate(2 * time.Second)
+	for i := range 5 {
+		s.AppendOverviewSample(base.Add(time.Duration(i*2)*time.Second), overviewTestStatus(float64(i)))
+	}
+	// overviewMetrics is the package singleton; the samples just appended
+	// must be visible through the aggregate the controller serves.
+	out := s.AggregateOverviewMetric("cpu", 2, 60)
+	if len(out) == 0 {
+		t.Fatal("AggregateOverviewMetric(cpu) returned no points after appends")
+	}
+	last := out[len(out)-1]
+	if got, _ := last["v"].(float64); got != 4 {
+		t.Fatalf("last cpu point = %v, want 4", last["v"])
+	}
+	for _, key := range OverviewMetricKeys {
+		if pts := s.AggregateOverviewMetric(key, 2, 60); len(pts) == 0 {
+			t.Fatalf("overview key %q has no points after AppendOverviewSample", key)
+		}
+	}
+}
+
+func TestOverviewRingIsBounded(t *testing.T) {
+	h := newMetricHistoryWithTiers([]tierSpec{{resolution: 2, capacity: 360}})
+	base := time.Unix(1_700_000_000, 0)
+	// Feed ten windows' worth of samples; the ring must not grow past its
+	// single tier capacity.
+	for i := range 3600 {
+		h.append("cpu", base.Add(time.Duration(i*2)*time.Second), float64(i))
+	}
+	// readSamples returns the closed buckets plus the still-open one, so the
+	// hard bound is capacity+1.
+	raw := h.series["cpu"].tiers[0].readSamples()
+	if len(raw) > 361 {
+		t.Fatalf("overview tier retained %d samples, want <= 361 (capacity + open bucket)", len(raw))
+	}
+	if len(raw) == 0 {
+		t.Fatal("overview tier retained no samples")
+	}
+}