cache: add SQLite route persistence; initial TTL and LRU eviction implementation

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: I0370d6c114d5490634905c1a831a31526a6a6964

internal/prober/prober_test.go

@@ -0,0 +1,100 @@
+package prober_test
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"notashelf.dev/ncro/internal/prober"
+)
+
+func TestEMACalculation(t *testing.T) {
+	p := prober.New(0.3)
+	p.RecordLatency("https://example.com", 100)
+	p.RecordLatency("https://example.com", 50)
+
+	// EMA after 2 measurements: first=100, second = 0.3*50 + 0.7*100 = 85
+	health := p.GetHealth("https://example.com")
+	if health == nil {
+		t.Fatal("expected health entry")
+	}
+	if health.EMALatency < 84 || health.EMALatency > 86 {
+		t.Errorf("EMA = %.2f, want ~85", health.EMALatency)
+	}
+}
+
+func TestStatusProgression(t *testing.T) {
+	p := prober.New(0.3)
+	p.RecordLatency("https://example.com", 10)
+
+	for range 3 {
+		p.RecordFailure("https://example.com")
+	}
+	h := p.GetHealth("https://example.com")
+	if h.Status != prober.StatusDegraded {
+		t.Errorf("status = %v, want Degraded after 3 failures", h.Status)
+	}
+
+	for range 7 {
+		p.RecordFailure("https://example.com")
+	}
+	h = p.GetHealth("https://example.com")
+	if h.Status != prober.StatusDown {
+		t.Errorf("status = %v, want Down after 10 failures", h.Status)
+	}
+}
+
+func TestRecoveryAfterSuccess(t *testing.T) {
+	p := prober.New(0.3)
+	for range 10 {
+		p.RecordFailure("https://example.com")
+	}
+	p.RecordLatency("https://example.com", 20)
+	h := p.GetHealth("https://example.com")
+	if h.Status != prober.StatusActive {
+		t.Errorf("status = %v, want Active after recovery", h.Status)
+	}
+	if h.ConsecutiveFails != 0 {
+		t.Errorf("ConsecutiveFails = %d, want 0", h.ConsecutiveFails)
+	}
+}
+
+func TestSortedByLatency(t *testing.T) {
+	p := prober.New(0.3)
+	p.RecordLatency("https://slow.example.com", 200)
+	p.RecordLatency("https://fast.example.com", 10)
+	p.RecordLatency("https://medium.example.com", 50)
+
+	sorted := p.SortedByLatency()
+	if len(sorted) != 3 {
+		t.Fatalf("expected 3, got %d", len(sorted))
+	}
+	if sorted[0].URL != "https://fast.example.com" {
+		t.Errorf("first = %q, want fast", sorted[0].URL)
+	}
+}
+
+func TestProbeUpstream(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(200)
+	}))
+	defer srv.Close()
+
+	p := prober.New(0.3)
+	p.ProbeUpstream(srv.URL)
+
+	h := p.GetHealth(srv.URL)
+	if h == nil || h.Status != prober.StatusActive {
+		t.Errorf("expected Active after successful probe, got %v", h)
+	}
+}
+
+func TestProbeUpstreamFailure(t *testing.T) {
+	p := prober.New(0.3)
+	p.ProbeUpstream("http://127.0.0.1:1") // nothing listening
+
+	h := p.GetHealth("http://127.0.0.1:1")
+	if h == nil || h.ConsecutiveFails == 0 {
+		t.Error("expected failure recorded")
+	}
+}