Add asinfo package for AS number information lookups

- Created pkg/asinfo with embedded AS data from ipverse/asn-info
- Provides fast lookups by ASN with GetDescription() and GetHandle()
- Includes Search() functionality for finding AS by name/handle
- Added asinfo-gen tool to fetch and convert CSV data to JSON
- Added 'make asupdate' target to refresh AS data
- Embedded JSON data contains 130k+ AS entries
- Added comprehensive tests and examples

pkg/asinfo/asinfo_test.go

@@ -0,0 +1,189 @@
+package asinfo
+
+import (
+	"testing"
+)
+
+func TestGet(t *testing.T) {
+	tests := []struct {
+		name     string
+		asn      int
+		wantOK   bool
+		wantDesc string
+	}{
+		{
+			name:     "AS1 Level 3",
+			asn:      1,
+			wantOK:   true,
+			wantDesc: "Level 3 Parent, LLC",
+		},
+		{
+			name:     "AS15169 Google",
+			asn:      15169,
+			wantOK:   true,
+			wantDesc: "Google LLC",
+		},
+		{
+			name:   "Non-existent AS",
+			asn:    999999999,
+			wantOK: false,
+		},
+		{
+			name:     "AS0 IANA Reserved",
+			asn:      0,
+			wantOK:   true,
+			wantDesc: "Internet Assigned Numbers Authority",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			info, ok := Get(tt.asn)
+			if ok != tt.wantOK {
+				t.Errorf("Get(%d) ok = %v, want %v", tt.asn, ok, tt.wantOK)
+				return
+			}
+			
+			if ok && info.Description != tt.wantDesc {
+				t.Errorf("Get(%d) description = %q, want %q", tt.asn, info.Description, tt.wantDesc)
+			}
+		})
+	}
+}
+
+func TestGetDescription(t *testing.T) {
+	tests := []struct {
+		asn  int
+		want string
+	}{
+		{1, "Level 3 Parent, LLC"},
+		{999999999, ""},
+	}
+
+	for _, tt := range tests {
+		t.Run("", func(t *testing.T) {
+			if got := GetDescription(tt.asn); got != tt.want {
+				t.Errorf("GetDescription(%d) = %q, want %q", tt.asn, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestGetHandle(t *testing.T) {
+	tests := []struct {
+		asn  int
+		want string
+	}{
+		{1, "LVLT"},
+		{0, "IANA-RSVD"},
+		{999999999, ""},
+	}
+
+	for _, tt := range tests {
+		t.Run("", func(t *testing.T) {
+			if got := GetHandle(tt.asn); got != tt.want {
+				t.Errorf("GetHandle(%d) = %q, want %q", tt.asn, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestTotal(t *testing.T) {
+	total := Total()
+	if total < 100000 {
+		t.Errorf("Total() = %d, expected > 100000", total)
+	}
+	
+	// Verify it's consistent
+	if total2 := Total(); total2 != total {
+		t.Errorf("Total() returned different values: %d vs %d", total, total2)
+	}
+}
+
+func TestSearch(t *testing.T) {
+	tests := []struct {
+		name    string
+		query   string
+		wantMin int
+	}{
+		{
+			name:    "Search for Google",
+			query:   "Google",
+			wantMin: 1,
+		},
+		{
+			name:    "Search for University",
+			query:   "University",
+			wantMin: 10,
+		},
+		{
+			name:    "Empty search",
+			query:   "",
+			wantMin: 0,
+		},
+		{
+			name:    "Non-existent org",
+			query:   "XYZABC123456",
+			wantMin: 0,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			results := Search(tt.query)
+			if len(results) < tt.wantMin {
+				t.Errorf("Search(%q) returned %d results, want at least %d", tt.query, len(results), tt.wantMin)
+			}
+			
+			// Verify all results contain the query
+			if tt.query != "" {
+				for _, r := range results {
+					if !contains(r.Handle, tt.query) && !contains(r.Description, tt.query) {
+						t.Errorf("Search result ASN %d doesn't contain query %q", r.ASN, tt.query)
+					}
+				}
+			}
+		})
+	}
+}
+
+func TestDataIntegrity(t *testing.T) {
+	// Verify no duplicate ASNs
+	all := All()
+	seen := make(map[int]bool)
+	for _, info := range all {
+		if seen[info.ASN] {
+			t.Errorf("Duplicate ASN found: %d", info.ASN)
+		}
+		seen[info.ASN] = true
+	}
+	
+	// Verify all entries have required fields
+	for _, info := range all {
+		if info.Handle == "" && info.ASN != 0 {
+			t.Errorf("ASN %d has empty handle", info.ASN)
+		}
+		if info.Description == "" {
+			t.Errorf("ASN %d has empty description", info.ASN)
+		}
+	}
+}
+
+func BenchmarkGet(b *testing.B) {
+	// Common ASNs to lookup
+	asns := []int{1, 15169, 13335, 32934, 8075, 16509}
+	
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		Get(asns[i%len(asns)])
+	}
+}
+
+func BenchmarkSearch(b *testing.B) {
+	queries := []string{"Google", "Amazon", "Microsoft", "University"}
+	
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		Search(queries[i%len(queries)])
+	}
+}