Show figures of the routing table on the home page (closes #154)

The home page gets cards for the newest and oldest kept route, the newest
and oldest updated AS, the AS with the most prefixes, the ASes with a
single prefix and fifteen well-known networks. Two more cards count the
bogon announcements and the prefixes with several origin ASes. They link
to the new pages /bogons and /multiple-origins, which list up to 1,000
entries each.

The new package internal/bogon tells reserved prefixes and AS numbers,
from the IANA special-purpose and address space registries. Table.Overview
walks the table and lets the read lock go every 10,000 prefixes. The
server works the cards out once a minute and serves that copy. A new index
on asns(last_seen) finds the newest and oldest updated AS.

Model: opus-5-5

internal/server/home_internal_test.go

@@ -0,0 +1,358 @@
+package server
+
+import (
+	"context"
+	"net/netip"
+	"strconv"
+	"strings"
+	"testing"
+	"time"
+
+	"git.eeqj.de/sneak/routewatch/internal/database"
+	"git.eeqj.de/sneak/routewatch/internal/routetable"
+)
+
+// The ASes of the routing table that newCardsTable fills. Each card test
+// finds one of them on its card.
+const (
+	twoPrefixASN   = 13335 // originates two prefixes, the most
+	newestRouteASN = 15169 // the newest route
+	oldestRouteASN = 3     // the oldest route
+	secondOrigin   = 16509 // a second origin AS of twoPrefixASN's prefix
+	privateUseASN  = 64512 // reserved, so its route is a bogon announcement
+)
+
+// Paths of the pages that list what two of the home page's cards count.
+const (
+	bogonsPath          = "/bogons"
+	multipleOriginsPath = "/multiple-origins"
+)
+
+// cardsNotReadyText is what the pages say before the cards are first worked
+// out.
+const cardsNotReadyText = "being worked out"
+
+// newCardsTable returns a routing table in which:
+//   - twoPrefixASN originates 1.0.0.0/24 and 1.0.4.0/22;
+//   - secondOrigin originates 1.0.0.0/24 too, which so has two origin ASes;
+//   - newestRouteASN's 8.8.8.0/24 has the newest route;
+//   - oldestRouteASN's 18.0.0.0/8 has the oldest;
+//   - privateUseASN originates 10.0.0.0/8, carried by two peers: a bogon
+//     announcement for both its prefix and its AS.
+//
+// The last four ASes originate one prefix each.
+func newCardsTable() *routetable.Table {
+	table := emptyTable()
+	announce(table, "1.0.0.0/24", twoPrefixASN, testPeer(1), testRouteTime(10))
+	announce(table, "1.0.4.0/22", twoPrefixASN, testPeer(1), testRouteTime(5))
+	announce(table, "1.0.0.0/24", secondOrigin, testPeer(3), testRouteTime(12))
+	announce(table, "8.8.8.0/24", newestRouteASN, testPeer(2), testRouteTime(20))
+	announce(table, "18.0.0.0/8", oldestRouteASN, testPeer(2), testRouteTime(1))
+	announce(table, "10.0.0.0/8", privateUseASN, testPeer(1), testRouteTime(15))
+	announce(table, "10.0.0.0/8", privateUseASN, testPeer(2), testRouteTime(15))
+
+	return table
+}
+
+// homeCard returns the HTML of the home page's card with heading, up to the
+// end of the card.
+func homeCard(t *testing.T, page, heading string) string {
+	t.Helper()
+
+	_, card, found := strings.Cut(page, "<h2>"+heading+"</h2>")
+	if !found {
+		t.Fatalf("the home page has no card %q", heading)
+	}
+
+	card, _, _ = strings.Cut(card, "</div>")
+
+	return card
+}
+
+// asLink returns the HTML attribute of a link to the AS page of asn.
+func asLink(asn int) string {
+	return `href="/as/` + strconv.Itoa(asn) + `"`
+}
+
+// TestHomePageCardsShowTheTableFigures fills a routing table and the asns
+// table, works out the cards, and checks that each card shows its figure.
+func TestHomePageCardsShowTheTableFigures(t *testing.T) {
+	t.Parallel()
+
+	const (
+		newestSeenASN = 6939
+		oldestSeenASN = 174
+	)
+
+	s := newServerWithTable(t, newCardsTable())
+
+	err := s.db.GetOrCreateASNBatch(map[int]database.SeenTimes{
+		newestSeenASN: {First: testRouteTime(0), Last: testRouteTime(30)},
+		oldestSeenASN: {First: testRouteTime(-30), Last: testRouteTime(-30)},
+	})
+	if err != nil {
+		t.Fatalf("GetOrCreateASNBatch: %v", err)
+	}
+
+	s.refreshHomeCards(t.Context())
+
+	page := get(t, s, "/").Body.String()
+
+	tests := []struct {
+		heading string
+		want    []string
+	}{
+		{"Newest Updated Route", []string{
+			"8.8.8.0/24", asLink(newestRouteASN),
+			testRouteTime(20).Format(routeTimeFormat),
+		}},
+		{"Oldest Updated Route", []string{
+			"18.0.0.0/8", asLink(oldestRouteASN),
+			testRouteTime(1).Format(routeTimeFormat),
+		}},
+		{"Newest Updated AS", []string{
+			asLink(newestSeenASN), testRouteTime(30).Format(routeTimeFormat),
+		}},
+		{"Oldest Updated AS", []string{
+			asLink(oldestSeenASN), testRouteTime(-30).Format(routeTimeFormat),
+		}},
+		{"AS with the Most Prefixes", []string{
+			asLink(twoPrefixASN), "Prefixes it originates: 2",
+		}},
+		{"ASes with the Fewest Prefixes", []string{
+			"ASes that originate a single prefix: 4", asLink(newestRouteASN),
+			"8.8.8.0/24",
+		}},
+		{"Bogon Announcements", []string{`href="/bogons">1<`}},
+		{"Prefixes with Several Origins", []string{`href="/multiple-origins">1<`}},
+	}
+
+	for _, tc := range tests {
+		card := homeCard(t, page, tc.heading)
+		for _, want := range tc.want {
+			if !strings.Contains(card, want) {
+				t.Errorf("card %q does not hold %s: %s", tc.heading, want, card)
+			}
+		}
+	}
+
+	// The well-known networks come newest update first, and those without
+	// a route after them.
+	networks := homeCard(t, page, "Well-Known Networks")
+	order := []int{newestRouteASN, secondOrigin, twoPrefixASN, oldestRouteASN, 714}
+	last := -1
+
+	for _, asn := range order {
+		i := strings.Index(networks, asLink(asn))
+		if i <= last {
+			t.Fatalf("well-known networks: AS%d is not after the ASes before "+
+				"it in %v: %s", asn, order, networks)
+		}
+
+		last = i
+	}
+
+	if !strings.Contains(networks, "<td>2</td>") {
+		t.Errorf("well-known networks: no network with 2 prefixes: %s", networks)
+	}
+}
+
+// TestListPagesListTheirEntries checks the rows of the bogon and multiple-origin
+// pages for the table of newCardsTable.
+func TestListPagesListTheirEntries(t *testing.T) {
+	t.Parallel()
+
+	s := newServerWithTable(t, newCardsTable())
+	s.refreshHomeCards(t.Context())
+
+	pages := map[string][]string{
+		bogonsPath: {
+			"Bogon announcements: 1.", "10.0.0.0/8", asLink(privateUseASN),
+			"<td>2</td>",
+			"Private-Use (10.0.0.0/8); Private-Use (AS64512-AS65534)",
+		},
+		multipleOriginsPath: {
+			"Prefixes announced by more than one origin AS: 1.", "1.0.0.0/24",
+			asLink(twoPrefixASN), asLink(secondOrigin), ">1 peer<",
+		},
+	}
+
+	for path, wants := range pages {
+		page := get(t, s, path).Body.String()
+		for _, want := range wants {
+			if !strings.Contains(page, want) {
+				t.Errorf("%s does not hold %s", path, want)
+			}
+		}
+	}
+}
+
+// TestListPagesListAtMostMaxListedEntries fills a table with more prefixes than
+// the list pages list, each announced by two origin ASes in reserved address
+// space. Each page lists maxListedEntries of them and gives how many there are
+// in all.
+func TestListPagesListAtMostMaxListedEntries(t *testing.T) {
+	t.Parallel()
+
+	const prefixCount = maxListedEntries + 1
+
+	table := emptyTable()
+	addr := netip.MustParseAddr("10.0.0.0")
+
+	for range prefixCount {
+		prefix := netip.PrefixFrom(addr, addr.BitLen()).String()
+		announce(table, prefix, twoPrefixASN, testPeer(1), testRouteTime(0))
+		announce(table, prefix, secondOrigin, testPeer(2), testRouteTime(0))
+
+		addr = addr.Next()
+	}
+
+	s := newServerWithTable(t, table)
+	s.refreshHomeCards(t.Context())
+
+	listed := "The first " + strconv.Itoa(maxListedEntries) + " are listed"
+	tests := []struct {
+		path  string
+		total string
+	}{
+		{bogonsPath, "Bogon announcements: " + strconv.Itoa(2*prefixCount) + "."},
+		{multipleOriginsPath, "Prefixes announced by more than one origin AS: " +
+			strconv.Itoa(prefixCount) + "."},
+	}
+
+	for _, tc := range tests {
+		page := get(t, s, tc.path).Body.String()
+
+		rows := strings.Count(page, `class="prefix-link"`)
+		if rows != maxListedEntries {
+			t.Errorf("%s lists %d entries, want %d", tc.path, rows,
+				maxListedEntries)
+		}
+
+		if !strings.Contains(page, tc.total) || !strings.Contains(page, listed) {
+			t.Errorf("%s does not say %q and %q", tc.path, tc.total, listed)
+		}
+	}
+}
+
+// TestPagesServeTheCopyOfTheCards checks that the pages show the cards as they
+// were last worked out, not as the routing table is now, and that they say so
+// before the cards are first worked out.
+func TestPagesServeTheCopyOfTheCards(t *testing.T) {
+	t.Parallel()
+
+	table := emptyTable()
+	announce(table, "1.0.0.0/24", twoPrefixASN, testPeer(1), testRouteTime(0))
+
+	s := newServerWithTable(t, table)
+
+	for _, path := range []string{"/", bogonsPath, multipleOriginsPath} {
+		if !strings.Contains(get(t, s, path).Body.String(), cardsNotReadyText) {
+			t.Errorf("%s does not say the cards are %s", path, cardsNotReadyText)
+		}
+	}
+
+	s.refreshHomeCards(t.Context())
+	announce(table, "8.8.8.0/24", newestRouteASN, testPeer(2), testRouteTime(1))
+
+	card := homeCard(t, get(t, s, "/").Body.String(), "Newest Updated Route")
+	if !strings.Contains(card, "1.0.0.0/24") {
+		t.Errorf("before the cards are worked out again, the newest route "+
+			"is not the one they were worked out with: %s", card)
+	}
+
+	s.refreshHomeCards(t.Context())
+
+	card = homeCard(t, get(t, s, "/").Body.String(), "Newest Updated Route")
+	if !strings.Contains(card, "8.8.8.0/24") {
+		t.Errorf("after the cards are worked out again, the newest route is "+
+			"not the table's: %s", card)
+	}
+}
+
+// TestKeepHomeCardsFreshWorksThemOutEveryInterval runs keepHomeCardsFresh with
+// a short interval. It works the cards out at once, again after the table
+// changes, and stops when its context ends.
+func TestKeepHomeCardsFreshWorksThemOutEveryInterval(t *testing.T) {
+	t.Parallel()
+
+	const (
+		interval = 10 * time.Millisecond
+		maxWait  = 5 * time.Second
+	)
+
+	table := emptyTable()
+	announce(table, "1.0.0.0/24", twoPrefixASN, testPeer(1), testRouteTime(0))
+
+	s := newServerWithTable(t, table)
+
+	ctx, cancel := context.WithCancel(t.Context())
+	stopped := make(chan struct{})
+
+	go func() {
+		s.keepHomeCardsFresh(ctx, interval)
+		close(stopped)
+	}()
+
+	newestRouteASNIs := func(asn int) bool {
+		cards := s.cards.Load()
+
+		return cards != nil && cards.NewestRoute != nil &&
+			cards.NewestRoute.OriginASN == asn
+	}
+
+	waitUntil(t, maxWait, func() bool { return newestRouteASNIs(twoPrefixASN) })
+
+	announce(table, "8.8.8.0/24", newestRouteASN, testPeer(2), testRouteTime(1))
+	waitUntil(t, maxWait, func() bool { return newestRouteASNIs(newestRouteASN) })
+
+	cancel()
+
+	select {
+	case <-stopped:
+	case <-time.After(maxWait):
+		t.Fatal("keepHomeCardsFresh did not stop when its context ended")
+	}
+}
+
+// TestStartedServerWorksOutTheCards starts a server and waits until its home
+// page shows the cards.
+func TestStartedServerWorksOutTheCards(t *testing.T) {
+	t.Parallel()
+
+	const maxWait = 5 * time.Second
+
+	s := newServerWithTable(t, newCardsTable())
+
+	err := s.Start(t.Context())
+	if err != nil {
+		t.Fatalf("Start: %v", err)
+	}
+
+	defer func() { _ = s.Stop(context.Background()) }()
+
+	waitUntil(t, maxWait, func() bool {
+		return !strings.Contains(get(t, s, "/").Body.String(), cardsNotReadyText)
+	})
+
+	card := homeCard(t, get(t, s, "/").Body.String(), "Newest Updated Route")
+	if !strings.Contains(card, "8.8.8.0/24") {
+		t.Errorf("the newest route is not the table's: %s", card)
+	}
+}
+
+// waitUntil fails the test unless done reports true within maxWait.
+func waitUntil(t *testing.T, maxWait time.Duration, done func() bool) {
+	t.Helper()
+
+	const pollInterval = 5 * time.Millisecond
+
+	deadline := time.Now().Add(maxWait)
+	for !done() {
+		if time.Now().After(deadline) {
+			t.Fatalf("the cards did not change within %s", maxWait)
+		}
+
+		time.Sleep(pollInterval)
+	}
+}