feat: enhance RefreshModule to support legacy ASN resolution and improve prefix handling. Introduce sorting of ASNs and manage announced prefixes with polite pauses for better API interaction. Update buildPreviewFragments to streamline route rendering for BIRD configurations.

internal/asnresolve/ripestat.go

@@ -0,0 +1,108 @@
+// Package asnresolve fetches IP prefixes announced by an ASN (control-plane ingest).
+package asnresolve
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/netip"
+	"os"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// DefaultRIPEStatURL is the RIPEstat announced-prefixes data call (no API key).
+const DefaultRIPEStatURL = "https://stat.ripe.net/data/announced-prefixes/data.json"
+
+// AnnouncedPrefixes returns currently announced IPv4/IPv6 prefixes for the ASN (best-effort via RIPEstat).
+func AnnouncedPrefixes(ctx context.Context, hc *http.Client, asn int64) ([]netip.Prefix, error) {
+	if hc == nil {
+		hc = http.DefaultClient
+	}
+	base := strings.TrimSpace(os.Getenv("EVOBGP_RIPESTAT_ANNOUNCED_PREFIXES_URL"))
+	if base == "" {
+		base = DefaultRIPEStatURL
+	}
+	u := fmt.Sprintf("%s?resource=AS%d", strings.TrimSuffix(base, "?"), asn)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, u, nil)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Accept", "application/json")
+	req.Header.Set("User-Agent", "evobgp-asnresolve/1.0")
+
+	resp, err := hc.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("ripestat fetch AS%d: %w", asn, err)
+	}
+	defer resp.Body.Close()
+	body, err := io.ReadAll(io.LimitReader(resp.Body, 32<<20))
+	if err != nil {
+		return nil, err
+	}
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("ripestat AS%d: HTTP %s: %s", asn, resp.Status, truncateForErr(body, 200))
+	}
+
+	var wrap struct {
+		Status  string `json:"status"`
+		Data    struct {
+			Prefixes []struct {
+				Prefix string `json:"prefix"`
+			} `json:"prefixes"`
+		} `json:"data"`
+		Messages [][]string `json:"messages"`
+	}
+	if err := json.Unmarshal(body, &wrap); err != nil {
+		return nil, fmt.Errorf("ripestat AS%d: json: %w", asn, err)
+	}
+	if wrap.Status != "" && wrap.Status != "ok" {
+		return nil, fmt.Errorf("ripestat AS%d: status %q", asn, wrap.Status)
+	}
+
+	var out []netip.Prefix
+	for _, row := range wrap.Data.Prefixes {
+		p := strings.TrimSpace(row.Prefix)
+		if p == "" {
+			continue
+		}
+		pfx, err := netip.ParsePrefix(p)
+		if err != nil {
+			continue
+		}
+		out = append(out, pfx.Masked())
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i].String() < out[j].String() })
+	return out, nil
+}
+
+func truncateForErr(b []byte, n int) string {
+	s := string(b)
+	if len(s) > n {
+		return s[:n] + "…"
+	}
+	return s
+}
+
+// PolitePause is a short delay between upstream ASN lookups (same refresh).
+func PolitePause() {
+	d := 150 * time.Millisecond
+	if s := strings.TrimSpace(os.Getenv("EVOBGP_ASN_RESOLVE_PAUSE_MS")); s != "" {
+		if ms, err := parsePositiveInt(s); err == nil && ms > 0 {
+			d = time.Duration(ms) * time.Millisecond
+		}
+	}
+	time.Sleep(d)
+}
+
+func parsePositiveInt(s string) (int, error) {
+	n, err := strconv.Atoi(s)
+	if err != nil || n <= 0 {
+		return 0, fmt.Errorf("invalid")
+	}
+	return n, nil
+}

internal/asnresolve/ripestat_test.go

@@ -0,0 +1,33 @@
+package asnresolve
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestAnnouncedPrefixes_Mock(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Query().Get("resource") != "AS64496" {
+			t.Fatalf("resource: %q", r.URL.Query().Get("resource"))
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(`{"status":"ok","data":{"prefixes":[{"prefix":"203.0.113.0/24"},{"prefix":"2001:db8::/32"}]}}`))
+	}))
+	defer ts.Close()
+
+	t.Setenv("EVOBGP_RIPESTAT_ANNOUNCED_PREFIXES_URL", ts.URL)
+	t.Setenv("EVOBGP_ASN_RESOLVE_PAUSE_MS", "1")
+
+	pfx, err := AnnouncedPrefixes(context.Background(), ts.Client(), 64496)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(pfx) != 2 {
+		t.Fatalf("got %d prefixes", len(pfx))
+	}
+	if pfx[0].String() != "2001:db8::/32" || pfx[1].String() != "203.0.113.0/24" {
+		t.Fatalf("order or values: %#v", pfx)
+	}
+}