Add orphan GC sweeper and Prometheus metrics with explicit registration

Co-Authored-By: Claude <noreply@anthropic.com>

internal/metrics/metrics_test.go

@@ -0,0 +1,113 @@
+package metrics
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/testutil"
+)
+
+// register wires a fresh registry — the reason Register exists instead of
+// init()-time self-registration.
+func register(t *testing.T, m *Metrics, phases map[string]int, active int) *prometheus.Registry {
+	t.Helper()
+	reg := prometheus.NewRegistry()
+	err := m.Register(reg,
+		func() map[string]int { return phases },
+		func() int { return active },
+	)
+	if err != nil {
+		t.Fatalf("Register: %v", err)
+	}
+	return reg
+}
+
+func TestRegister_scrapeTimeCollectors(t *testing.T) {
+	t.Parallel()
+	m := New()
+	reg := register(t, m, map[string]int{"Ready": 3, "Provisioning": 1}, 7)
+
+	expected := `
+# HELP proxy_operator_leases_active Currently active leases.
+# TYPE proxy_operator_leases_active gauge
+proxy_operator_leases_active 7
+# HELP proxy_operator_proxies Proxy objects by phase.
+# TYPE proxy_operator_proxies gauge
+proxy_operator_proxies{phase="Provisioning"} 1
+proxy_operator_proxies{phase="Ready"} 3
+`
+	if err := testutil.GatherAndCompare(reg, strings.NewReader(expected),
+		"proxy_operator_proxies", "proxy_operator_leases_active"); err != nil {
+		t.Error(err)
+	}
+}
+
+func TestObserveProbe_andForget(t *testing.T) {
+	t.Parallel()
+	m := New()
+	reg := register(t, m, nil, 0)
+
+	m.ObserveProbe("default/p1", 30*time.Millisecond, true)
+	m.ObserveProbe("default/p1", 40*time.Millisecond, false)
+	m.ObserveProbe("default/p2", 10*time.Millisecond, true)
+
+	if got := testutil.CollectAndCount(m.healthcheckDuration); got != 2 {
+		t.Errorf("duration series = %d, want 2 (one per proxy)", got)
+	}
+	if got := testutil.ToFloat64(m.healthcheckFailures.WithLabelValues("default/p1")); got != 1 {
+		t.Errorf("p1 failures = %v, want 1 (only the failed probe)", got)
+	}
+
+	m.ForgetProxy("default/p1")
+	if got := testutil.CollectAndCount(m.healthcheckDuration); got != 1 {
+		t.Errorf("duration series after ForgetProxy = %d, want 1 — series must not leak", got)
+	}
+	if got := testutil.CollectAndCount(m.healthcheckFailures); got != 0 {
+		t.Errorf("failure series after ForgetProxy = %d, want 0", got)
+	}
+	_ = reg
+}
+
+func TestLeaseRequest(t *testing.T) {
+	t.Parallel()
+	m := New()
+	register(t, m, nil, 0)
+
+	m.LeaseRequest("granted")
+	m.LeaseRequest("granted")
+	m.LeaseRequest("no_match")
+
+	if got := testutil.ToFloat64(m.leaseRequests.WithLabelValues("granted")); got != 2 {
+		t.Errorf("granted = %v, want 2", got)
+	}
+	if got := testutil.ToFloat64(m.leaseRequests.WithLabelValues("no_match")); got != 1 {
+		t.Errorf("no_match = %v, want 1", got)
+	}
+}
+
+func TestProviderRequest(t *testing.T) {
+	t.Parallel()
+	m := New()
+	register(t, m, nil, 0)
+
+	m.ProviderRequest("gcp-eu", "create", "ok")
+	m.ProviderRequest("gcp-eu", "create", "quota_exceeded")
+
+	if got := testutil.ToFloat64(m.providerRequests.WithLabelValues("gcp-eu", "create", "ok")); got != 1 {
+		t.Errorf("ok = %v, want 1", got)
+	}
+	if got := testutil.ToFloat64(m.providerRequests.WithLabelValues("gcp-eu", "create", "quota_exceeded")); got != 1 {
+		t.Errorf("quota_exceeded = %v, want 1", got)
+	}
+}
+
+func TestRegister_freshRegistryPerTest(t *testing.T) {
+	t.Parallel()
+	// Registering the same metric set on two registries must both succeed —
+	// the property init()-style global registration would break.
+	m1, m2 := New(), New()
+	register(t, m1, nil, 0)
+	register(t, m2, nil, 0)
+}