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

The event log gains three links above the list: All, Failed (N) and
Pending (N), carried in a `show` query parameter; any other value shows
every event. Failed lists the events with a failed delivery, Pending
those with one pending or retrying, each once, under the full list's
50-row limit and order. A filtered list finds the matching deliveries
through `idx_deliveries_status`, looks up their events by ID and sorts
them, and reads the rows of only the events shown; its counts read the
deliveries alone. The line beside the heading says what a filter
counts, and Replay returns to the list it was pressed in. The README
and the comments naming the query parameters the service reads include
`show`.

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) {