Event log: show only the events with a failed or a pending delivery (closes #390)

The event log had no way to list only the events whose delivery failed, and once it showed only the 50 newest, an older failure could not be found at all. It now has All, Failed (N) and Pending (N) links, carried in a `show` query parameter, so they work without the page's script library. Each filtered list keeps the 50-row limit and newest-first order, and lists an event once. It finds matching deliveries through `idx_deliveries_status` and looks their events up by ID, so its cost follows the matches, not the webhook's size. Replay returns to the list it was pressed in. The heading line says what a filter counts.

Model: opus-5-5

internal/handlers/source_logs_test.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"net/http"
 	"net/http/httptest"
+	"slices"
 	"strings"
 	"testing"
 	"time"
@@ -186,6 +187,152 @@ func TestHandleSourceLogs_ShowsFiftyNewestEvents(t *testing.T) {
 	assert.Contains(t, body, "50 most recent of 51 events")
 }
 
+// TestHandleSourceLogs_ShowsEventsByDeliveryStatus proves that the
+// Failed list holds exactly the events with a failed delivery, the
+// Pending list exactly those with a delivery pending or retrying, each
+// once, and any other show value every event; that each link, and the
+// line beside the heading, counts the events its list holds; and that
+// the shown link is marked.
+func TestHandleSourceLogs_ShowsEventsByDeliveryStatus(t *testing.T) {
+	t.Parallel()
+
+	f := newRecentEventsFixture(t)
+	target := seedTarget(t, f.db, f.webhook.ID, database.TargetTypeLog)
+	now := time.Now()
+
+	const (
+		failed    = database.DeliveryStatusFailed
+		delivered = database.DeliveryStatusDelivered
+		pending   = database.DeliveryStatusPending
+		retrying  = database.DeliveryStatusRetrying
+	)
+
+	// Each event is named by its content type. The first failed and
+	// was then replayed and delivered. The second failed, and so did
+	// its replay, and the fifth has one delivery pending and another
+	// retrying: each must still be listed and counted once.
+	events := []struct {
+		contentType string
+		deliveries  []database.DeliveryStatus
+	}{
+		{"application/x-failed", []database.DeliveryStatus{failed, delivered}},
+		{"application/x-failed-twice", []database.DeliveryStatus{failed, failed}},
+		{"application/x-pending", []database.DeliveryStatus{pending}},
+		{"application/x-retrying", []database.DeliveryStatus{retrying}},
+		{"application/x-pending-retrying", []database.DeliveryStatus{pending, retrying}},
+		{"application/x-delivered", []database.DeliveryStatus{delivered}},
+		{"application/x-no-delivery", nil},
+	}
+
+	all := make([]string, len(events))
+
+	for i, e := range events {
+		event := f.event(
+			t, e.contentType, "{}", now.Add(time.Duration(i)*time.Second),
+		)
+
+		for _, status := range e.deliveries {
+			f.delivery(t, event, target.ID, status)
+		}
+
+		all[i] = e.contentType
+	}
+
+	for _, tc := range []struct {
+		query   string
+		current string
+		heading string
+		listed  []string
+	}{
+		{"", "All", "7 total events", all},
+		{"?show=failed", "Failed (2)", "2 events with a failed delivery",
+			[]string{"application/x-failed", "application/x-failed-twice"}},
+		{"?show=pending", "Pending (3)",
+			"3 events with a delivery pending or retrying", []string{
+				"application/x-pending", "application/x-retrying",
+				"application/x-pending-retrying",
+			}},
+		{"?show=unknown", "All", "7 total events", all},
+	} {
+		body := renderSourceLogsPageWithQuery(
+			t, f.h, f.sess, f.webhook.ID, tc.query,
+		)
+
+		// One row per listed event, so with each listed event shown
+		// no event is listed twice.
+		assert.Equal(t, len(tc.listed),
+			strings.Count(body, `role="button"`), tc.query)
+
+		for _, contentType := range all {
+			assert.Equal(t,
+				slices.Contains(tc.listed, contentType),
+				strings.Contains(body, ">"+contentType+"<"),
+				tc.query+" "+contentType)
+		}
+
+		assert.Contains(t, body, ">"+tc.heading+"<", tc.query)
+		assert.Contains(t, body, "Failed (2)", tc.query)
+		assert.Contains(t, body, "Pending (3)", tc.query)
+		assert.Equal(t, 1, strings.Count(body, "aria-current"), tc.query)
+		assert.Contains(t, body,
+			`aria-current="page">`+tc.current+"</a>", tc.query)
+	}
+}
+
+// TestHandleSourceLogs_FilteredListShowsFiftyNewest proves a filtered
+// list holds the 50 newest matching events, as the full log does,
+// while its link and heading count every matching event.
+func TestHandleSourceLogs_FilteredListShowsFiftyNewest(t *testing.T) {
+	t.Parallel()
+
+	f := newRecentEventsFixture(t)
+	target := seedTarget(t, f.db, f.webhook.ID, database.TargetTypeLog)
+	base := time.Now().Add(-time.Hour)
+
+	for i := range 51 {
+		event := f.event(
+			t, fmt.Sprintf("application/x-failed-%02d", i), "{}",
+			base.Add(time.Duration(i)*time.Second),
+		)
+		f.delivery(t, event, target.ID, database.DeliveryStatusFailed)
+	}
+
+	// The newest event has no failed delivery.
+	f.event(t, "application/x-no-delivery", "{}", time.Now())
+
+	body := renderSourceLogsPageWithQuery(
+		t, f.h, f.sess, f.webhook.ID, "?show=failed",
+	)
+
+	assert.Equal(t, 50, strings.Count(body, `role="button"`))
+	assert.NotContains(t, body, "application/x-failed-00")
+	assert.NotContains(t, body, "application/x-no-delivery")
+	assert.Contains(t, body, "Failed (51)")
+	assert.Contains(t, body,
+		"50 most recent of 51 events with a failed delivery")
+}
+
+// TestHandleSourceLogs_EmptyFilteredList proves an empty filtered list
+// says that no event matches rather than that none was recorded.
+func TestHandleSourceLogs_EmptyFilteredList(t *testing.T) {
+	t.Parallel()
+
+	f := newRecentEventsFixture(t)
+	target := seedTarget(t, f.db, f.webhook.ID, database.TargetTypeLog)
+
+	f.delivery(
+		t, f.event(t, contentTypeJSON, "{}", time.Now()),
+		target.ID, database.DeliveryStatusDelivered,
+	)
+
+	assert.Contains(t, renderSourceLogsPageWithQuery(
+		t, f.h, f.sess, f.webhook.ID, "?show=failed",
+	), "No event has a failed delivery.")
+	assert.Contains(t, renderSourceLogsPageWithQuery(
+		t, f.h, f.sess, f.webhook.ID, "?show=pending",
+	), "No event has a delivery pending or retrying.")
+}
+
 // TestHandleSourceLogs_OnlyNewestStartsExpanded proves that of the
 // events in the log only the newest starts expanded.
 func TestHandleSourceLogs_OnlyNewestStartsExpanded(t *testing.T) {