feat: implement traversal engine (HAN-380) (#6)

Co-authored-by: Hansen IT Solutions <gary@hansenits.com> Co-committed-by: Hansen IT Solutions <gary@hansenits.com>
2026-06-06 03:41:14 +00:00
parent 194bc97526
commit 39529dacbb
11 changed files with 2098 additions and 0 deletions
@@ -0,0 +1,203 @@
+package traverse
+
+import (
+	"fmt"
+	"net"
+	"strings"
+	"sync"
+	"testing"
+
+	"github.com/miekg/dns"
+)
+
+func TestNewInfoCache(t *testing.T) {
+	c := NewInfoCache(nil)
+	if c.parent != nil {
+		t.Error("root cache should have nil parent")
+	}
+	if c.NSCount() != 0 {
+		t.Errorf("NSCount = %d, want 0", c.NSCount())
+	}
+	if c.GlueCount() != 0 {
+		t.Errorf("GlueCount = %d, want 0", c.GlueCount())
+	}
+}
+
+func TestInfoCacheStoreAndLookupNS(t *testing.T) {
+	c := NewInfoCache(nil)
+
+	c.StoreNS("com.", []string{"a.gtld-servers.net.", "b.gtld-servers.net."})
+	if c.NSCount() != 1 {
+		t.Errorf("NSCount = %d, want 1", c.NSCount())
+	}
+
+	names := c.LookupNS("com.")
+	if len(names) != 2 {
+		t.Fatalf("expected 2 nameservers, got %d", len(names))
+	}
+	if names[0] != "a.gtld-servers.net." {
+		t.Errorf("nameserver[0] = %q, want %q", names[0], "a.gtld-servers.net.")
+	}
+}
+
+func TestInfoCacheNSDedup(t *testing.T) {
+	c := NewInfoCache(nil)
+	c.StoreNS("com.", []string{"a.gtld-servers.net.", "a.gtld-servers.net."})
+	names := c.LookupNS("com.")
+	if len(names) != 1 {
+		t.Errorf("expected 1 deduped NS, got %d", len(names))
+	}
+}
+
+func TestInfoCacheNSCaseInsensitive(t *testing.T) {
+	c := NewInfoCache(nil)
+	c.StoreNS("COM.", []string{"A.GTLD-SERVERS.NET."})
+	names := c.LookupNS("com.")
+	if len(names) != 1 {
+		t.Fatalf("expected 1 NS, got %d", len(names))
+	}
+	if names[0] != "a.gtld-servers.net." {
+		t.Errorf("NS = %q, want %q", names[0], "a.gtld-servers.net.")
+	}
+}
+
+func TestInfoCacheNSLookupMiss(t *testing.T) {
+	c := NewInfoCache(nil)
+	names := c.LookupNS("org.")
+	if names != nil {
+		t.Errorf("expected nil for miss, got %v", names)
+	}
+}
+
+func TestInfoCacheNSStoreEmpty(t *testing.T) {
+	c := NewInfoCache(nil)
+	c.StoreNS("com.", nil)
+	if c.NSCount() != 0 {
+		t.Errorf("expected 0 after empty store, got %d", c.NSCount())
+	}
+}
+
+func TestInfoCacheChainedNS(t *testing.T) {
+	parent := NewInfoCache(nil)
+	parent.StoreNS("com.", []string{"a.gtld-servers.net."})
+
+	child := parent.Child()
+	if child.parent != parent {
+		t.Error("child parent should be the parent cache")
+	}
+
+	names := child.LookupNS("com.")
+	if len(names) != 1 {
+		t.Fatalf("expected 1 NS from parent, got %d", len(names))
+	}
+	if child.NSCount() != 0 {
+		t.Errorf("child NSCount = %d, want 0", child.NSCount())
+	}
+}
+
+func TestInfoCacheChildOverridesParent(t *testing.T) {
+	parent := NewInfoCache(nil)
+	parent.StoreNS("com.", []string{"a.gtld-servers.net."})
+
+	child := parent.Child()
+	child.StoreNS("com.", []string{"b.gtld-servers.net."})
+
+	names := child.LookupNS("com.")
+	if len(names) != 1 {
+		t.Fatalf("expected 1 NS, got %d", len(names))
+	}
+	if names[0] != "b.gtld-servers.net." {
+		t.Errorf("expected child's NS to override, got %q", names[0])
+	}
+}
+
+func TestInfoCacheStoreAndLookupGlue(t *testing.T) {
+	c := NewInfoCache(nil)
+	addrs := []net.IP{net.ParseIP("1.2.3.4"), net.ParseIP("5.6.7.8")}
+	c.StoreGlue("ns1.example.com.", addrs)
+
+	result := c.LookupGlue("ns1.example.com.")
+	if len(result) != 2 {
+		t.Fatalf("expected 2 glue addresses, got %d", len(result))
+	}
+}
+
+func TestInfoCacheGlueDedup(t *testing.T) {
+	c := NewInfoCache(nil)
+	ip := net.ParseIP("1.2.3.4")
+	c.StoreGlue("ns1.example.com.", []net.IP{ip, ip})
+	result := c.LookupGlue("ns1.example.com.")
+	if len(result) != 1 {
+		t.Errorf("expected 1 deduped glue, got %d", len(result))
+	}
+}
+
+func TestInfoCacheChainedGlue(t *testing.T) {
+	parent := NewInfoCache(nil)
+	parent.StoreGlue("ns1.example.com.", []net.IP{net.ParseIP("1.2.3.4")})
+
+	child := parent.Child()
+	result := child.LookupGlue("ns1.example.com.")
+	if len(result) != 1 {
+		t.Fatalf("expected 1 glue from parent, got %d", len(result))
+	}
+	if child.GlueCount() != 0 {
+		t.Errorf("child GlueCount = %d, want 0", child.GlueCount())
+	}
+}
+
+func TestInfoCacheGlueLookupMiss(t *testing.T) {
+	c := NewInfoCache(nil)
+	result := c.LookupGlue("nonexistent.example.com.")
+	if result != nil {
+		t.Errorf("expected nil for miss, got %v", result)
+	}
+}
+
+func TestInfoCacheConcurrentAccess(t *testing.T) {
+	c := NewInfoCache(nil)
+	var wg sync.WaitGroup
+
+	for i := 0; i < 100; i++ {
+		wg.Add(1)
+		go func(i int) {
+			defer wg.Done()
+			name := strings.ToLower(dns.Fqdn(fmt.Sprintf("ns%d.example.com.", i)))
+			c.StoreNS("example.com.", []string{name})
+			c.StoreGlue(name, []net.IP{net.ParseIP(fmt.Sprintf("1.2.3.%d", i%256))})
+			_ = c.LookupNS("example.com.")
+			_ = c.LookupGlue(name)
+		}(i)
+	}
+	wg.Wait()
+}
+
+func TestInfoCacheNilParent(t *testing.T) {
+	c := NewInfoCache(nil)
+	if c.LookupNS("com.") != nil {
+		t.Error("root cache should return nil for miss")
+	}
+	if c.LookupGlue("ns.example.com.") != nil {
+		t.Error("root cache should return nil for glue miss")
+	}
+}
+
+func TestNormalize(t *testing.T) {
+	tests := []struct {
+		input string
+		want  string
+	}{
+		{"example.com", "example.com."},
+		{"Example.COM.", "example.com."},
+		{"EXAMPLE.COM", "example.com."},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			got := normalize(tt.input)
+			if got != tt.want {
+				t.Errorf("normalize(%q) = %q, want %q", tt.input, got, tt.want)
+			}
+		})
+	}
+}