Store a new row's earliest timestamp as first_seen (closes #112)

Each handler took the latest time per key in a batch and inserted it as
a new row's first_seen, so a key updated twice in one batch, seconds
apart, was stored first seen at the later time, and the IP lookup could
answer with a prefix first_seen after the route's last_seen.

The prefix handler now keeps the earliest time of all of the batch's
updates for each prefix. The AS, peer and peering handlers keep the
earliest and the latest time per key in database.SeenTimes, and
GetOrCreateASNBatch, UpdatePeerBatch and RecordPeering store a new row
first seen at the earliest and last seen at the latest. A stored row
still has only its last_seen set, to the latest.

Model: opus-5-5

internal/routewatch/peeringhandler_internal_test.go

@@ -31,12 +31,14 @@ type recordingStore struct {
 	calls int
 }
 
-func (r *recordingStore) RecordPeering(asA, asB int, ts time.Time) error {
+func (r *recordingStore) RecordPeering(
+	asA, asB int, seen database.SeenTimes,
+) error {
 	r.mu.Lock()
 	r.calls++
 	r.mu.Unlock()
 
-	return r.mockStore.RecordPeering(asA, asB, ts)
+	return r.mockStore.RecordPeering(asA, asB, seen)
 }
 
 func (r *recordingStore) callCount() int {
@@ -52,7 +54,7 @@ func newTestHandler(db database.Store) *PeeringHandler {
 	return &PeeringHandler{
 		db:      db,
 		logger:  logger.New(),
-		asPaths: make(map[string]time.Time),
+		asPaths: make(map[string]database.SeenTimes),
 	}
 }
 
@@ -220,10 +222,10 @@ func TestPeeringHandlerCapDropsAndCounts(t *testing.T) {
 	existing := pathKey(t, testASNA, testASNB)
 
 	h.mu.Lock()
-	h.asPaths[existing] = now
+	h.asPaths[existing] = database.SeenTimes{First: now, Last: now}
 
 	for i := 0; len(h.asPaths) < maxTrackedPaths; i++ {
-		h.asPaths[strconv.Itoa(i)] = now
+		h.asPaths[strconv.Itoa(i)] = database.SeenTimes{First: now, Last: now}
 	}
 	h.mu.Unlock()
 
@@ -253,11 +255,53 @@ func TestPeeringHandlerCapDropsAndCounts(t *testing.T) {
 	}
 
 	h.mu.Lock()
-	gotTS := h.asPaths[existing]
+	gotSeen := h.asPaths[existing]
 	h.mu.Unlock()
 
-	if !gotTS.Equal(refreshed) {
-		t.Fatalf("existing path timestamp not refreshed: want %v, got %v",
-			refreshed, gotTS)
+	if !gotSeen.Last.Equal(refreshed) {
+		t.Fatalf("existing path last seen not refreshed: want %v, got %v",
+			refreshed, gotSeen.Last)
+	}
+}
+
+// TestPeeringHandlerStoresTheEarliestAndLatestTimesOfANewPeering handles two
+// updates whose path carries a peering the database does not hold yet, the
+// second 5 seconds after the first, in one run into a real database. The
+// peering is stored first seen at the time of the first update and last seen
+// at the time of the second.
+func TestPeeringHandlerStoresTheEarliestAndLatestTimesOfANewPeering(
+	t *testing.T,
+) {
+	t.Parallel()
+
+	db := newTestDatabase(t)
+	h := newTestHandler(db)
+
+	first := peerAnnouncement(testPeerIP, testV4Prefix)
+	second := peerAnnouncement(testPeerIP, testV4Prefix)
+	second.ParsedTimestamp = first.ParsedTimestamp.Add(secondUpdateAfter)
+
+	h.HandleMessage(first)
+	h.HandleMessage(second)
+	h.ProcessPeeringsNow()
+
+	peers, err := db.GetASPeers(testASNA)
+	if err != nil {
+		t.Fatalf("GetASPeers(%d): %v", testASNA, err)
+	}
+
+	if len(peers) != 1 || peers[0].ASN != testASNB {
+		t.Fatalf("peers of AS%d = %+v, want AS%d alone", testASNA, peers,
+			testASNB)
+	}
+
+	if !peers[0].FirstSeen.Equal(first.ParsedTimestamp) {
+		t.Errorf("first_seen of peering AS%d-AS%d = %s, want %s", testASNA,
+			testASNB, peers[0].FirstSeen, first.ParsedTimestamp)
+	}
+
+	if !peers[0].LastSeen.Equal(second.ParsedTimestamp) {
+		t.Errorf("last_seen of peering AS%d-AS%d = %s, want %s", testASNA,
+			testASNB, peers[0].LastSeen, second.ParsedTimestamp)
 	}
 }