Render admin page errors in the normal layout (closes #382)

Every 400, 403, 404 and 500 on an admin page now answers with an
error page in the normal layout: one fixed line for the status and a
link back to the webhook list, or to sign-in when nobody is signed
in. The router's handler for unknown paths, the CSRF middleware's
refusal and a panic in an admin page route group use the same page;
each such group has its own recoverer and error reporting for that.
The page always sends Cache-Control: no-store. Status codes are
unchanged. The receiver, the healthcheck and /metrics keep their
plain answers. If the error page cannot render, or panics, the answer
is the same status in plain text.

Model: opus-5-5

README.md

@@ -1075,7 +1075,7 @@ unconditionally against whatever files it finds:
 - the main database on connect — `Setting`, `User`, `APIKey`, `Webhook`,
   `Entrypoint`, `Target`
 - each event database when it is lazily opened — `Event`, `Delivery`,
-  `DeliveryResult`, `EventTotals`, `TargetTotals`
+  `DeliveryResult`
 - each archive database on every open and reopen
 
 There is no schema version table, no migration ledger, and no down
@@ -1392,7 +1392,7 @@ The codebase uses consistent naming throughout (rename completed in
 
 ### Data Model
 
-webhooker's data model has eleven entities organized into two tiers: the
+webhooker's data model has nine entities organized into two tiers: the
 **application tier** (user and webhook configuration) and the **event
 tier** (event ingestion, delivery, and logging).
 
@@ -1421,13 +1421,6 @@ tier** (event ingestion, delivery, and logging).
 │  ┌──────────┐       ┌──────────┐       ┌─────────────────┐  │
 │  │  Event   │──1:N──│ Delivery │──1:N──│ DeliveryResult  │  │
 │  └──────────┘       └──────────┘       └─────────────────┘  │
-│                                                             │
-│  ┌──────────────┐  (one row: running counts of events)      │
-│  │ EventTotals  │                                           │
-│  └──────────────┘                                           │
-│  ┌──────────────┐  (one row per target: running counts      │
-│  │ TargetTotals │   of its deliveries)                      │
-│  └──────────────┘                                           │
 └─────────────────────────────────────────────────────────────┘
 ```
 
@@ -1681,7 +1674,6 @@ status across potentially multiple attempts.
 | `event_id` | UUID           | Foreign key → Event |
 | `target_id`| UUID           | Foreign key → Target |
 | `status`   | DeliveryStatus | One of: `pending`, `delivered`, `failed`, `retrying` |
-| `finished_at` | timestamp   | When the delivery became `delivered` or `failed` (nullable; empty while `pending` or `retrying`) |
 
 **Relations:** Belongs to Event. Belongs to Target. Has many
 DeliveryResults.
@@ -1749,66 +1741,33 @@ retries) is individually logged for full observability.
 
 **Relations:** Belongs to Delivery.
 
-#### EventTotals and TargetTotals
-
-Running counts in each event database, read by the statistics pane at the
-top of the webhook page. `EventTotals` is one row:
-
-| Field            | Type    | Description |
-| ---------------- | ------- | ----------- |
-| `events`         | integer | Events ever stored, resubmitted copies included |
-| `events_removed` | integer | Events retention has deleted |
-
-`TargetTotals` is one row per target, created by the first delivery to it:
-
-| Field                | Type    | Description |
-| -------------------- | ------- | ----------- |
-| `target_id`          | UUID    | The target (primary key) |
-| `deliveries`         | integer | Deliveries to it ever created, replays included |
-| `delivered`          | integer | Of those, how many became `delivered` |
-| `failed`             | integer | Of those, how many became `failed` |
-| `deliveries_removed` | integer | Its deliveries retention has deleted |
-| `failed_removed`     | integer | Its failed deliveries retention has deleted |
-
-Each count changes in the transaction that writes or deletes the rows it
-counts. The pane's lifetime events are `events`, and its lifetime
-deliveries and failures are `deliveries` and `failed` summed over the
-targets; each figure within retention is the same less what retention
-removed, so neither needs the rows themselves. Its last-10-minutes and
-last-24-hours figures are counted from the `events` and `deliveries`
-indexes over just that window, the deliveries in one query grouped by
-target. Its failure percentage for a window is the deliveries that became
-`failed` in it out of all that became `delivered` or `failed` in it, and
-a dash when none did.
-
 #### Event-tier indexes
 
 These indexes on the per-webhook event databases are declared in the model
-tags, so `AutoMigrate` creates them on a fresh database:
+tags, so `AutoMigrate` creates them on a fresh and on an existing database:
 
 | Table              | Columns                     | Serves |
 | ------------------ | --------------------------- | ------ |
-| `deliveries`       | `status`, `deleted_at`, `finished_at`, `target_id` | Startup recovery, the retry and pending sweeps every 60 seconds and the queue-depth sampler every 30 seconds, which select deliveries by status, and the webhook page's statistics, which count each target's deliveries by status and when they finished |
-| `deliveries`       | `event_id`, `deleted_at`    | The event log, which loads each event's deliveries, and retention, which counts and deletes the deliveries of expired events |
+| `deliveries`       | `status`, `deleted_at`      | Startup recovery, the retry and pending sweeps every 60 seconds and the queue-depth sampler every 30 seconds, which select deliveries by status |
+| `deliveries`       | `event_id`, `deleted_at`    | The event log, which loads each event's deliveries, and retention, which selects and deletes the deliveries of expired events |
 | `delivery_results` | `delivery_id`, `deleted_at` | The event log, which loads the attempts of a page's deliveries, and retention, which deletes the attempts of expired events |
-| `events`           | `deleted_at`, `created_at`  | The webhook page's statistics, which count recent events and find the newest |
-| `events`           | `created_at`                | Retention, which selects expired events by age |
+| `events`           | `deleted_at`, `created_at`  | Retention, which selects expired events by age |
+| `events`           | `created_at`                | Retention's delete of the expired events themselves |
 
-GORM's soft delete adds `deleted_at IS NULL` to these queries; retention
-leaves it out. SQLite keeps no statistics on these tables, and without them it
-rates the `deleted_at` index, which every live row matches, above an index on
-a column matched against several values or compared with a range. So every
-index but the last also covers `deleted_at`. It comes second, so that
-retention can use the index without it, except in `events`, where the
-statistics compare `created_at` with a range (`>=`) and SQLite narrows by a
-range only on the last column it uses.
+GORM's soft delete adds `deleted_at IS NULL` to these queries; retention's
+deletes leave it out, but their lookups of expired rows keep it. SQLite keeps
+no statistics on these tables, and without them it rates the `deleted_at`
+index, which every live row matches, above an index on a column matched
+against several values or compared with `<`. So every index but the last also
+covers `deleted_at`. It comes second, so that retention's deletes can use the
+index without it, except in `events`, where `created_at` is compared with `<`
+and SQLite narrows by a `<` only on the last column it uses.
 
 #### Common Fields
 
-Every entity except `Setting`, `EventTotals` and `TargetTotals` includes
-these fields from `BaseModel`. `Setting` is a bare key-value row with no
-`id`, no timestamps and no soft delete, and the two totals tables hold
-only counts, keyed by a numeric `id` and by `target_id`:
+Every entity except `Setting` includes these fields from `BaseModel`.
+`Setting` is a bare key-value row with no `id`, no timestamps and no
+soft delete:
 
 | Field        | Type      | Description |
 | ------------ | --------- | ----------- |
@@ -1850,8 +1809,6 @@ encryption key is generated and stored, and an `admin` user is created.
 - **Events** — captured incoming webhook payloads
 - **Deliveries** — event-to-target pairings and their status
 - **DeliveryResults** — individual delivery attempt logs
-- **EventTotals** and **TargetTotals** — running counts of the above,
-  the deliveries per target, kept through retention
 
 Per-webhook databases are created automatically when a webhook is
 created (and lazily on first access for webhooks that predate this
@@ -2831,7 +2788,6 @@ webhooker/
 │   │   ├── model_event.go     # Event entity (per-webhook DB)
 │   │   ├── model_delivery.go  # Delivery entity (per-webhook DB)
 │   │   ├── model_delivery_result.go  # DeliveryResult entity (per-webhook DB)
-│   │   ├── model_totals.go    # EventTotals and TargetTotals (per-webhook DB)
 │   │   ├── model_apikey.go    # APIKey entity
 │   │   ├── password.go        # Argon2id hashing and verification
 │   │   ├── retention.go       # Retention reaper (per-webhook event expiry)

internal/database/event_tier_indexes_test.go

@@ -93,11 +93,11 @@ func TestEventTierQueriesUseTheirIndexes(t *testing.T) {
 		deliveries []database.Delivery
 		results    []database.DeliveryResult
 		depths     []struct{ Depth int }
-		removed    []database.TargetTotals
 	)
 
 	byStatus := "idx_deliveries_status (status=? AND deleted_at=?)"
 	byEvent := "idx_deliveries_event_id (event_id=? AND deleted_at=?)"
+	byAge := "idx_events_deleted_at_created_at (deleted_at=? AND created_at<?)"
 
 	// The delivery engine: recovery and the retry sweep, the sweep for
 	// stranded pending deliveries, and the queue depth count.
@@ -123,89 +123,25 @@ func TestEventTierQueriesUseTheirIndexes(t *testing.T) {
 		Order("attempt_num ASC").Find(&results),
 		"idx_delivery_results_delivery_id (delivery_id=? AND deleted_at=?)")
 
-	// Retention (reapExpired, deleteEvents): one batch of expired
-	// events, then their attempts, deliveries and the events.
-	var expired []string
-
-	assertPlanUses(t, db, dry.Unscoped().Model(&database.Event{}).
-		Where("created_at < ?", cutoff).
-		Limit(database.ExportReapBatchSize).Pluck("id", &expired),
-		"idx_events_created_at (created_at<?)")
-	assertPlanUses(t, db, dry.Unscoped().Where(
-		"delivery_id IN (?)", dry.Unscoped().Model(&database.Delivery{}).
-			Select("id").Where("event_id IN ?", ids),
-	).Delete(&database.DeliveryResult{}),
-		"idx_delivery_results_delivery_id (delivery_id=?)",
-		"idx_deliveries_event_id (event_id=?)")
-	assertPlanUses(t, db, dry.Unscoped().Model(&database.Delivery{}).
-		Select("target_id, count(*) AS deliveries_removed, "+
-			"count(CASE WHEN status = ? THEN 1 END) AS failed_removed",
-			database.DeliveryStatusFailed).
-		Where("event_id IN ?", ids).Group("target_id").Find(&removed),
-		"idx_deliveries_event_id (event_id=?)")
-	assertPlanUses(t, db, dry.Unscoped().Where("event_id IN ?", ids).
-		Delete(&database.Delivery{}), "idx_deliveries_event_id (event_id=?)")
-	assertPlanUses(t, db, dry.Unscoped().Where("id IN ?", ids).
-		Delete(&database.Event{}), "sqlite_autoindex_events_1 (id=?)")
+	// Retention's three deletes (reapExpired), whose subqueries are built
+	// afresh for each statement as it builds them.
+	expiredEventIDs := func() *gorm.DB {
+		return dry.Model(&database.Event{}).Select("id").
+			Where("created_at < ?", cutoff)
 	}
 
-// TestStatisticsQueriesUseTheirIndexes does the same for the webhook
-// page's statistics (readEventStats in the handlers): deliveries in
-// progress, each target's deliveries finished since a time, which must
-// come from the index alone, events received since a time, and the
-// newest event, which must come straight off an index rather than from
-// sorting every event.
-func TestStatisticsQueriesUseTheirIndexes(t *testing.T) {
-	t.Parallel()
-
-	mgr, lc := setupTestWebhookDBManager(t)
-	ctx := context.Background()
-	require.NoError(t, lc.Start(ctx))
-
-	defer func() { require.NoError(t, lc.Stop(ctx)) }()
-
-	db, err := mgr.GetDB(uuid.New().String())
-	require.NoError(t, err)
-
-	dry := db.Session(&gorm.Session{DryRun: true})
-	since := time.Now()
-
-	var (
-		count    int64
-		newest   []time.Time
-		byTarget []struct{ TargetID string }
-	)
-
-	assertPlanUses(t, db, dry.Model(&database.Delivery{}).
-		Where("status IN ?", []database.DeliveryStatus{
-			database.DeliveryStatusPending,
-			database.DeliveryStatusRetrying,
-		}).Count(&count),
-		"idx_deliveries_status (status=? AND deleted_at=?)")
-	assertPlanUses(t, db, dry.Model(&database.Delivery{}).
-		Select("target_id, "+
-			"count(CASE WHEN status = ? THEN 1 END) AS delivered, "+
-			"count(CASE WHEN status = ? THEN 1 END) AS failed",
-			database.DeliveryStatusDelivered,
-			database.DeliveryStatusFailed).
-		Where("status IN ? AND finished_at >= ?",
-			[]database.DeliveryStatus{
-				database.DeliveryStatusDelivered,
-				database.DeliveryStatusFailed,
-			}, since).
-		Group("target_id").Find(&byTarget),
-		"COVERING INDEX idx_deliveries_status "+
-			"(status=? AND deleted_at=? AND finished_at>?)")
-	assertPlanUses(t, db, dry.Model(&database.Event{}).
-		Where("created_at >= ?", since).Count(&count),
-		"idx_events_deleted_at_created_at "+
-			"(deleted_at=? AND created_at>?)")
-
-	newestEvent := dry.Model(&database.Event{}).
-		Order("created_at DESC").Limit(1).Pluck("created_at", &newest)
-	assertPlanUses(t, db, newestEvent,
-		"idx_events_deleted_at_created_at (deleted_at=?)")
-	assert.NotContains(t, queryPlan(t, db, newestEvent), "TEMP B-TREE")
+	assertPlanUses(t, db, dry.Unscoped().Where(
+		"delivery_id IN (?)", dry.Model(&database.Delivery{}).
+			Select("id").Where("event_id IN (?)", expiredEventIDs()),
+	).Delete(&database.DeliveryResult{}),
+		"idx_delivery_results_delivery_id (delivery_id=?)", byEvent, byAge)
+	assertPlanUses(t, db, dry.Unscoped().Where(
+		"event_id IN (?)", expiredEventIDs(),
+	).Delete(&database.Delivery{}),
+		"idx_deliveries_event_id (event_id=?)", byAge)
+	assertPlanUses(t, db, dry.Unscoped().Where(
+		"created_at < ?", cutoff,
+	).Delete(&database.Event{}), "idx_events_created_at (created_at<?)")
 }
 
 // assertPlanUses asserts that SQLite's plan for a statement GORM built
@@ -216,18 +152,6 @@ func assertPlanUses(
 ) {
 	t.Helper()
 
-	plan := queryPlan(t, db, built)
-
-	for _, index := range indexes {
-		assert.Contains(t, plan, index, built.Statement.SQL.String())
-	}
-}
-
-// queryPlan returns SQLite's plan for a statement GORM built in a dry
-// run, run with the same SQL and arguments GORM would send.
-func queryPlan(t *testing.T, db, built *gorm.DB) string {
-	t.Helper()
-
 	var plan []struct{ Detail string }
 
 	require.NoError(t, db.Raw(
@@ -235,5 +159,8 @@ func queryPlan(t *testing.T, db, built *gorm.DB) string {
 		built.Statement.Vars...,
 	).Scan(&plan).Error)
 
-	return fmt.Sprint(plan)
+	for _, index := range indexes {
+		assert.Contains(t, fmt.Sprint(plan), index,
+			built.Statement.SQL.String())
+	}
 }

internal/database/export_test.go

@@ -28,10 +28,6 @@ func NewTestRetentionReaper(
 	}
 }
 
-// ExportReapBatchSize exposes how many expired events one retention
-// transaction deletes.
-const ExportReapBatchSize = reapBatchSize
-
 // ExportSweep runs a single retention sweep synchronously for tests.
 func (r *RetentionReaper) ExportSweep(ctx context.Context) {
 	r.sweep(ctx)

internal/database/model_delivery.go

@@ -1,10 +1,6 @@
 package database
 
-import (
-	"time"
-
-	"gorm.io/gorm"
-)
+import "gorm.io/gorm"
 
 // DeliveryStatus represents the status of a delivery
 type DeliveryStatus string
@@ -41,7 +37,7 @@ type Delivery struct {
 	BaseModel
 
 	EventID  string         `gorm:"type:uuid;not null;index:idx_deliveries_event_id,priority:1"       json:"eventId"`
-	TargetID string         `gorm:"type:uuid;not null;index:idx_deliveries_status,priority:4"         json:"targetId"`
+	TargetID string         `gorm:"type:uuid;not null"                                                json:"targetId"`
 	Status   DeliveryStatus `gorm:"not null;default:'pending';index:idx_deliveries_status,priority:1" json:"status"`
 
 	// DeletedAt repeats the BaseModel field only to be the second column
@@ -49,13 +45,6 @@ type Delivery struct {
 	// gives.
 	DeletedAt gorm.DeletedAt `gorm:"index:idx_deliveries_event_id,priority:2;index:idx_deliveries_status,priority:2" json:"deletedAt,omitzero"`
 
-	// FinishedAt is when the delivery became delivered or failed, and
-	// nil while it is pending or retrying. It and then TargetID end the
-	// status index, so the webhook page counts each target's deliveries
-	// that finished in a recent window by reading just that window from
-	// the index.
-	FinishedAt *time.Time `gorm:"index:idx_deliveries_status,priority:3" json:"finishedAt,omitempty"`
-
 	// Relations
 	Event           Event            `json:"event,omitzero"`
 	Target          Target           `json:"target,omitzero"`

internal/database/model_totals.go

@@ -1,91 +0,0 @@
-package database
-
-import (
-	"fmt"
-
-	"gorm.io/gorm"
-)
-
-// The running totals in a webhook's event database keep the webhook
-// page's lifetime figures right after retention has removed the rows
-// they count, and let the page show them without counting every row.
-// Each total changes in the transaction that writes or deletes the
-// rows it counts.
-
-// EventTotals is the single row counting a webhook's events: every
-// event ever stored, and how many of them retention has deleted.
-type EventTotals struct {
-	ID int64 `gorm:"primaryKey"`
-
-	Events        int64 `gorm:"not null"`
-	EventsRemoved int64 `gorm:"not null"`
-}
-
-// TableName names the table AddEventTotals updates.
-func (EventTotals) TableName() string {
-	return "event_totals"
-}
-
-// TargetTotals is one row per target counting its deliveries: every
-// delivery ever created, how many became delivered and how many
-// failed, and how many deliveries and failed deliveries retention has
-// deleted. The webhook's delivery figures are these rows summed.
-type TargetTotals struct {
-	TargetID string `gorm:"type:uuid;primaryKey"`
-
-	Deliveries int64 `gorm:"not null"`
-	Delivered  int64 `gorm:"not null"`
-	Failed     int64 `gorm:"not null"`
-
-	DeliveriesRemoved int64 `gorm:"not null"`
-	FailedRemoved     int64 `gorm:"not null"`
-}
-
-// TableName names the table AddTargetTotals updates.
-func (TargetTotals) TableName() string {
-	return "target_totals"
-}
-
-// AddEventTotals adds each count in add to the webhook's event totals.
-// Call it on the transaction that writes or deletes the events it
-// counts.
-func AddEventTotals(tx *gorm.DB, add EventTotals) error {
-	err := tx.Exec(
-		`UPDATE event_totals SET
-			events = events + ?,
-			events_removed = events_removed + ?`,
-		add.Events, add.EventsRemoved,
-	).Error
-	if err != nil {
-		return fmt.Errorf("adding to event totals: %w", err)
-	}
-
-	return nil
-}
-
-// AddTargetTotals adds each count in add to the totals of the target
-// add.TargetID names, creating its row the first time. Call it on the
-// transaction that writes or deletes the deliveries it counts.
-func AddTargetTotals(tx *gorm.DB, add TargetTotals) error {
-	err := tx.Exec(
-		`INSERT INTO target_totals (target_id, deliveries, delivered,
-			failed, deliveries_removed, failed_removed)
-		VALUES (?, ?, ?, ?, ?, ?)
-		ON CONFLICT (target_id) DO UPDATE SET
-			deliveries = deliveries + excluded.deliveries,
-			delivered = delivered + excluded.delivered,
-			failed = failed + excluded.failed,
-			deliveries_removed =
-				deliveries_removed + excluded.deliveries_removed,
-			failed_removed = failed_removed + excluded.failed_removed`,
-		add.TargetID, add.Deliveries, add.Delivered,
-		add.Failed, add.DeliveriesRemoved, add.FailedRemoved,
-	).Error
-	if err != nil {
-		return fmt.Errorf(
-			"adding to totals of target %s: %w", add.TargetID, err,
-		)
-	}
-
-	return nil
-}

internal/database/models.go

@@ -2,8 +2,7 @@ package database
 
 // Migrate runs database migrations for the main application database.
 // Only configuration-tier models are stored in the main database.
-// Event-tier models (Event, Delivery, DeliveryResult, EventTotals,
-// TargetTotals) live in
+// Event-tier models (Event, Delivery, DeliveryResult) live in
 // per-webhook dedicated databases managed by WebhookDBManager.
 func (d *Database) Migrate() error {
 	return d.db.AutoMigrate(

internal/database/retention.go

@@ -18,19 +18,6 @@ import (
 // computation.
 const hoursPerDay = 24
 
-// reapBatchSize is how many expired events one retention transaction
-// deletes. A transaction holds the event database's write lock, which
-// the receiver and the delivery workers wait for, so a large prune is
-// split into transactions each short enough to finish well inside the
-// busy timeout.
-const reapBatchSize = 1000
-
-// reapBatchPause is how long retention waits after one batch before
-// starting the next. A writer waiting for the write lock checks for it
-// again after at most 100 ms, so a longer pause lets it in between two
-// batches instead of only after the whole prune.
-const reapBatchPause = 200 * time.Millisecond
-
 // RetentionReaperParams holds the fx dependencies for the
 // RetentionReaper.
 type RetentionReaperParams struct {
@@ -278,99 +265,57 @@ func retentionCutoff(
 	), true
 }
 
-// reapExpired hard-deletes the events older than cutoff, with their
-// deliveries and delivery results, reapBatchSize events per
-// transaction with reapBatchPause between transactions, until none is
-// left. It returns the number of events deleted.
+// reapExpired hard-deletes, in foreign-key-safe order, the delivery
+// results, deliveries, and events associated with events older than
+// cutoff. Deletes are unscoped so rows are physically removed rather
+// than soft-deleted, reclaiming disk. It returns the number of events
+// deleted.
 func reapExpired(db *gorm.DB, cutoff time.Time) (int64, error) {
-	var total int64
-
-	for {
-		var eventIDs []string
-
-		err := db.Transaction(func(tx *gorm.DB) error {
-			err := tx.Unscoped().Model(&Event{}).
-				Where("created_at < ?", cutoff).
-				Limit(reapBatchSize).
-				Pluck("id", &eventIDs).Error
-			if err != nil {
-				return fmt.Errorf("selecting expired events: %w", err)
-			}
-
-			if len(eventIDs) == 0 {
-				return nil
-			}
-
-			return deleteEvents(tx, eventIDs)
-		})
-		if err != nil {
-			return total, err
-		}
-
-		total += int64(len(eventIDs))
-
-		if len(eventIDs) < reapBatchSize {
-			return total, nil
-		}
-
-		time.Sleep(reapBatchPause)
-	}
-}
-
-// deleteEvents hard-deletes the given events and, in foreign-key-safe
-// order before them, their delivery results and deliveries, then adds
-// what it deleted to the running totals. It runs on reapExpired's
-// transaction, so the totals change exactly when the rows do. Deletes
-// are unscoped so rows are physically removed rather than
-// soft-deleted, reclaiming disk.
-func deleteEvents(tx *gorm.DB, eventIDs []string) error {
-	// 1. The delivery results of the events' deliveries.
-	err := tx.Unscoped().
-		Where("delivery_id IN (?)", tx.Unscoped().Model(&Delivery{}).
+	// Fresh subqueries are built per statement to avoid reusing a
+	// mutated builder across executions.
+	expiredEventIDs := func() *gorm.DB {
+		return db.Model(&Event{}).
 			Select("id").
-			Where("event_id IN ?", eventIDs)).
-		Delete(&DeliveryResult{}).Error
-	if err != nil {
-		return fmt.Errorf("deleting expired delivery results: %w", err)
+			Where("created_at < ?", cutoff)
+	}
+	expiredDeliveryIDs := func() *gorm.DB {
+		return db.Model(&Delivery{}).
+			Select("id").
+			Where("event_id IN (?)", expiredEventIDs())
 	}
 
-	// 2. The events' deliveries, after counting them, and the failed
-	// ones among them, per target. The status is tested in the select
-	// list rather than the WHERE clause: there, SQLite would read every
-	// failed delivery the webhook has through the status index,
-	// instead of only these through the event_id index.
-	var removed []TargetTotals
-
-	err = tx.Unscoped().Model(&Delivery{}).
-		Select("target_id, count(*) AS deliveries_removed, "+
-			"count(CASE WHEN status = ? THEN 1 END) AS failed_removed",
-			DeliveryStatusFailed).
-		Where("event_id IN ?", eventIDs).
-		Group("target_id").
-		Find(&removed).Error
-	if err != nil {
-		return fmt.Errorf("counting expired deliveries: %w", err)
+	// 1. Delivery results whose delivery belongs to an expired event.
+	res := db.Unscoped().
+		Where("delivery_id IN (?)", expiredDeliveryIDs()).
+		Delete(&DeliveryResult{})
+	if res.Error != nil {
+		return 0, fmt.Errorf(
+			"deleting expired delivery results: %w",
+			res.Error,
+		)
 	}
 
-	err = tx.Unscoped().
-		Where("event_id IN ?", eventIDs).
-		Delete(&Delivery{}).Error
-	if err != nil {
-		return fmt.Errorf("deleting expired deliveries: %w", err)
+	// 2. Deliveries belonging to an expired event.
+	del := db.Unscoped().
+		Where("event_id IN (?)", expiredEventIDs()).
+		Delete(&Delivery{})
+	if del.Error != nil {
+		return 0, fmt.Errorf(
+			"deleting expired deliveries: %w",
+			del.Error,
+		)
 	}
 
-	// 3. The events themselves.
-	ev := tx.Unscoped().Where("id IN ?", eventIDs).Delete(&Event{})
+	// 3. The expired events themselves.
+	ev := db.Unscoped().
+		Where("created_at < ?", cutoff).
+		Delete(&Event{})
 	if ev.Error != nil {
-		return fmt.Errorf("deleting expired events: %w", ev.Error)
+		return 0, fmt.Errorf(
+			"deleting expired events: %w",
+			ev.Error,
+		)
 	}
 
-	for i := range removed {
-		err = AddTargetTotals(tx, removed[i])
-		if err != nil {
-			return err
-		}
-	}
-
-	return AddEventTotals(tx, EventTotals{EventsRemoved: ev.RowsAffected})
+	return ev.RowsAffected, nil
 }

internal/database/totals_test.go

@@ -1,305 +0,0 @@
-package database_test
-
-import (
-	"context"
-	"net/http"
-	"testing"
-	"time"
-
-	"github.com/google/uuid"
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-	"gorm.io/gorm"
-	"sneak.berlin/go/webhooker/internal/database"
-)
-
-// readEventTotals reads a webhook database's row of event totals,
-// asserting that it has exactly one.
-func readEventTotals(t *testing.T, db *gorm.DB) database.EventTotals {
-	t.Helper()
-
-	var rows []database.EventTotals
-
-	require.NoError(t, db.Find(&rows).Error)
-	require.Len(t, rows, 1)
-
-	return rows[0]
-}
-
-// readTargetTotals reads a webhook database's target totals, keyed by
-// target.
-func readTargetTotals(
-	t *testing.T, db *gorm.DB,
-) map[string]database.TargetTotals {
-	t.Helper()
-
-	var rows []database.TargetTotals
-
-	require.NoError(t, db.Find(&rows).Error)
-
-	byTarget := make(map[string]database.TargetTotals, len(rows))
-	for _, row := range rows {
-		byTarget[row.TargetID] = row
-	}
-
-	return byTarget
-}
-
-// TestWebhookDBManager_TotalsSurviveReopen verifies that a new event
-// database starts with one row of zero event totals and no target
-// totals, that adding to a target twice adds to the one row, and that
-// opening the database again keeps everything added.
-func TestWebhookDBManager_TotalsSurviveReopen(t *testing.T) {
-	t.Parallel()
-
-	mgr, lc := setupTestWebhookDBManager(t)
-	ctx := context.Background()
-	require.NoError(t, lc.Start(ctx))
-
-	defer func() { require.NoError(t, lc.Stop(ctx)) }()
-
-	webhookID := uuid.New().String()
-
-	db, err := mgr.GetDB(webhookID)
-	require.NoError(t, err)
-
-	fresh := readEventTotals(t, db)
-	assert.Equal(t, database.EventTotals{ID: fresh.ID}, fresh)
-	assert.Empty(t, readTargetTotals(t, db))
-
-	first, second := uuid.New().String(), uuid.New().String()
-
-	require.NoError(t, database.AddEventTotals(db, database.EventTotals{
-		Events: 2,
-	}))
-	require.NoError(t, database.AddTargetTotals(db, database.TargetTotals{
-		TargetID: first, Deliveries: 2, Delivered: 1,
-	}))
-	require.NoError(t, database.AddTargetTotals(db, database.TargetTotals{
-		TargetID: first, Failed: 1,
-	}))
-	require.NoError(t, database.AddTargetTotals(db, database.TargetTotals{
-		TargetID: second, Deliveries: 1,
-	}))
-
-	// Drop the cached connection so the next open reopens the file,
-	// as a restart would.
-	require.NoError(t, mgr.CloseAll())
-
-	db, err = mgr.GetDB(webhookID)
-	require.NoError(t, err)
-
-	assert.Equal(t, database.EventTotals{ID: fresh.ID, Events: 2},
-		readEventTotals(t, db))
-	assert.Equal(t, map[string]database.TargetTotals{
-		first: {
-			TargetID: first, Deliveries: 2, Delivered: 1, Failed: 1,
-		},
-		second: {TargetID: second, Deliveries: 1},
-	}, readTargetTotals(t, db))
-}
-
-// seedExpiredEvents stores count events created at the given time,
-// each with a delivered delivery to one target and a failed delivery
-// to the other, and one attempt for each delivery.
-func seedExpiredEvents(
-	t *testing.T,
-	db *gorm.DB,
-	webhookID string,
-	count int,
-	createdAt time.Time,
-	delivered, failed string,
-) {
-	t.Helper()
-
-	events := make([]database.Event, count)
-	deliveries := make([]database.Delivery, 0, 2*count)
-
-	for i := range events {
-		events[i] = database.Event{
-			WebhookID:    webhookID,
-			EntrypointID: uuid.New().String(),
-			Method:       http.MethodPost,
-		}
-		events[i].ID = uuid.New().String()
-		events[i].CreatedAt = createdAt
-
-		deliveries = append(deliveries,
-			database.Delivery{
-				EventID:  events[i].ID,
-				TargetID: delivered,
-				Status:   database.DeliveryStatusDelivered,
-			},
-			database.Delivery{
-				EventID:  events[i].ID,
-				TargetID: failed,
-				Status:   database.DeliveryStatusFailed,
-			},
-		)
-	}
-
-	require.NoError(t, db.CreateInBatches(events, 500).Error)
-	require.NoError(t, db.CreateInBatches(deliveries, 500).Error)
-
-	results := make([]database.DeliveryResult, len(deliveries))
-	for i := range deliveries {
-		results[i] = database.DeliveryResult{
-			DeliveryID: deliveries[i].ID, AttemptNum: 1,
-		}
-	}
-
-	require.NoError(t, db.CreateInBatches(results, 500).Error)
-}
-
-// TestRetentionReaper_PrunesMoreThanOneBatch verifies that a prune
-// larger than one transaction's batch removes every expired event with
-// its deliveries and delivery results, keeps the recent event, and
-// adds what it removed to the event and target totals, so the totals
-// within retention match the rows still stored.
-func TestRetentionReaper_PrunesMoreThanOneBatch(t *testing.T) {
-	t.Parallel()
-
-	env := setupRetentionTest(t)
-
-	webhookID := createWebhook(t, env.mainDB.DB(), 30)
-
-	db, err := env.mgr.GetDB(webhookID)
-	require.NoError(t, err)
-
-	expired := database.ExportReapBatchSize + 1
-	delivered, failed := uuid.New().String(), uuid.New().String()
-	seedExpiredEvents(t, db, webhookID, expired,
-		time.Now().Add(-40*24*time.Hour), delivered, failed)
-
-	// One recent event, delivered to the first target.
-	recent := seedEventChain(t, db, webhookID, time.Now())
-	require.NoError(t, db.Model(&database.Delivery{}).
-		Where("id = ?", recent.deliveryID).
-		Update("target_id", delivered).Error)
-
-	// The totals storing those rows would have left.
-	n := int64(expired)
-	require.NoError(t, database.AddEventTotals(db, database.EventTotals{
-		Events: n + 1,
-	}))
-	require.NoError(t, database.AddTargetTotals(db, database.TargetTotals{
-		TargetID: delivered, Deliveries: n + 1, Delivered: n + 1,
-	}))
-	require.NoError(t, database.AddTargetTotals(db, database.TargetTotals{
-		TargetID: failed, Deliveries: n, Failed: n,
-	}))
-
-	env.reaper.ExportSweep(context.Background())
-
-	// Only the recent event's rows are left.
-	for _, model := range []any{
-		&database.Event{}, &database.Delivery{}, &database.DeliveryResult{},
-	} {
-		var count int64
-
-		require.NoError(t, db.Model(model).Count(&count).Error)
-		assert.Equal(t, int64(1), count, "%T rows left", model)
-	}
-
-	assertChainPresent(t, db, recent)
-
-	eventTotals := readEventTotals(t, db)
-	assert.Equal(t, database.EventTotals{
-		ID: eventTotals.ID, Events: n + 1, EventsRemoved: n,
-	}, eventTotals)
-
-	targetTotals := readTargetTotals(t, db)
-	assert.Equal(t, map[string]database.TargetTotals{
-		delivered: {
-			TargetID: delivered, Deliveries: n + 1, Delivered: n + 1,
-			DeliveriesRemoved: n,
-		},
-		failed: {
-			TargetID: failed, Deliveries: n, Failed: n,
-			DeliveriesRemoved: n, FailedRemoved: n,
-		},
-	}, targetTotals)
-
-	// A sweep with nothing left to remove changes nothing.
-	env.reaper.ExportSweep(context.Background())
-
-	assert.Equal(t, eventTotals, readEventTotals(t, db))
-	assert.Equal(t, targetTotals, readTargetTotals(t, db))
-}
-
-// TestRetentionReaper_WriteDuringPruneSucceeds verifies that a prune
-// of several batches lets other writers in between its batches: an
-// event stored once the first batch is deleted is stored while expired
-// events are still left, not only after the prune has finished.
-func TestRetentionReaper_WriteDuringPruneSucceeds(t *testing.T) {
-	t.Parallel()
-
-	env := setupRetentionTest(t)
-
-	webhookID := createWebhook(t, env.mainDB.DB(), 30)
-
-	db, err := env.mgr.GetDB(webhookID)
-	require.NoError(t, err)
-
-	// Three batches of expired events, with nothing else stored: only
-	// the number of batches matters here.
-	expired := make([]database.Event, 3*database.ExportReapBatchSize)
-	for i := range expired {
-		expired[i] = database.Event{
-			WebhookID:    webhookID,
-			EntrypointID: uuid.New().String(),
-			Method:       http.MethodPost,
-		}
-		expired[i].CreatedAt = time.Now().Add(-40 * 24 * time.Hour)
-	}
-
-	require.NoError(t, db.CreateInBatches(expired, 500).Error)
-
-	cutoff := time.Now().Add(-30 * 24 * time.Hour)
-	countExpired := func() int64 {
-		var count int64
-
-		require.NoError(t, db.Model(&database.Event{}).
-			Where("created_at < ?", cutoff).
-			Count(&count).Error)
-
-		return count
-	}
-
-	pruned := make(chan struct{})
-
-	go func() {
-		defer close(pruned)
-
-		env.reaper.ExportSweep(context.Background())
-	}()
-
-	t.Cleanup(func() { <-pruned })
-
-	// Every stored event is expired until the write below.
-	require.Eventually(t, func() bool {
-		var count int64
-
-		err := db.Model(&database.Event{}).Count(&count).Error
-
-		return err == nil && count < int64(len(expired))
-	}, 10*time.Second, 10*time.Millisecond)
-
-	event := &database.Event{
-		WebhookID:    webhookID,
-		EntrypointID: uuid.New().String(),
-		Method:       http.MethodPost,
-	}
-	require.NoError(t, db.Create(event).Error)
-
-	assert.Positive(t, countExpired(),
-		"the event was stored only after the whole prune")
-
-	<-pruned
-
-	assert.Zero(t, countExpired())
-
-	var stored database.Event
-
-	require.NoError(t, db.First(&stored, "id = ?", event.ID).Error)
-}

internal/database/webhook_db_manager.go

@@ -35,8 +35,7 @@ var errInvalidCachedDBType = errors.New(
 
 // WebhookDBManager manages per-webhook SQLite database files
 // for event storage. Each webhook gets its own dedicated
-// database containing Events, Deliveries, DeliveryResults and the
-// running totals of them (EventTotals, TargetTotals).
+// database containing Events, Deliveries, and DeliveryResults.
 // Database connections are opened lazily and cached.
 type WebhookDBManager struct {
 	dataDir string
@@ -296,7 +295,6 @@ func (m *WebhookDBManager) openDB(
 	// Run migrations for event-tier models only
 	err = db.AutoMigrate(
 		&Event{}, &Delivery{}, &DeliveryResult{},
-		&EventTotals{}, &TargetTotals{},
 	)
 	if err != nil {
 		_ = sqlDB.Close()
@@ -307,18 +305,6 @@ func (m *WebhookDBManager) openDB(
 		)
 	}
 
-	// A new database gets its row of event totals, all zero. Target
-	// totals rows are created by the first delivery to each target.
-	err = db.FirstOrCreate(&EventTotals{}).Error
-	if err != nil {
-		_ = sqlDB.Close()
-
-		return nil, fmt.Errorf(
-			"creating event totals for webhook database %s: %w",
-			webhookID, err,
-		)
-	}
-
 	m.log.Info(
 		"opened per-webhook database",
 		"webhook_id", webhookID,

internal/delivery/delivery_totals_test.go

@@ -1,116 +0,0 @@
-package delivery_test
-
-import (
-	"testing"
-	"time"
-
-	"github.com/google/uuid"
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-	"gorm.io/gorm"
-	"sneak.berlin/go/webhooker/internal/database"
-)
-
-// targetTotals reads one target's totals from a webhook database, all
-// zero when it has no row.
-func targetTotals(
-	t *testing.T, db *gorm.DB, targetID string,
-) database.TargetTotals {
-	t.Helper()
-
-	var rows []database.TargetTotals
-
-	require.NoError(t, db.Where("target_id = ?", targetID).
-		Find(&rows).Error)
-
-	if len(rows) == 0 {
-		return database.TargetTotals{TargetID: targetID}
-	}
-
-	return rows[0]
-}
-
-// TestUpdateDeliveryStatus_FinishTimeAndTargetTotals pins what a status
-// write records for the webhook page's statistics: the time a delivery
-// finished, set only when it becomes delivered or failed, and one more
-// on its target's delivered or failed total.
-func TestUpdateDeliveryStatus_FinishTimeAndTargetTotals(t *testing.T) {
-	t.Parallel()
-
-	tests := []struct {
-		status    database.DeliveryStatus
-		finished  bool
-		delivered int64
-		failed    int64
-	}{
-		{database.DeliveryStatusRetrying, false, 0, 0},
-		{database.DeliveryStatusDelivered, true, 1, 0},
-		{database.DeliveryStatusFailed, true, 0, 1},
-	}
-
-	for _, tt := range tests {
-		t.Run(string(tt.status), func(t *testing.T) {
-			t.Parallel()
-
-			db := testWebhookDB(t)
-			e := testEngine(t, 1)
-			event := seedEvent(t, db, `{}`)
-			targetID := uuid.New().String()
-			d := seedDelivery(
-				t, db, event.ID, targetID,
-				database.DeliveryStatusPending,
-			)
-
-			before := time.Now()
-
-			require.NoError(t, e.ExportUpdateDeliveryStatus(
-				db, &d, tt.status,
-			))
-
-			var stored database.Delivery
-
-			require.NoError(t, db.First(&stored, "id = ?", d.ID).Error)
-			assert.Equal(t, tt.status, stored.Status)
-
-			if tt.finished {
-				require.NotNil(t, stored.FinishedAt)
-				assert.False(t, stored.FinishedAt.Before(before))
-			} else {
-				assert.Nil(t, stored.FinishedAt)
-			}
-
-			assert.Equal(t, database.TargetTotals{
-				TargetID:  targetID,
-				Delivered: tt.delivered,
-				Failed:    tt.failed,
-			}, targetTotals(t, db, targetID))
-		})
-	}
-}
-
-// TestUpdateDeliveryStatus_DeletedDeliveryIsNotCounted covers a
-// delivery retention deleted while the engine still held it. Failing
-// it afterwards writes no row, so it adds no failure either: retention
-// has already counted what it removed.
-func TestUpdateDeliveryStatus_DeletedDeliveryIsNotCounted(t *testing.T) {
-	t.Parallel()
-
-	db := testWebhookDB(t)
-	e := testEngine(t, 1)
-	event := seedEvent(t, db, `{}`)
-	targetID := uuid.New().String()
-	d := seedDelivery(
-		t, db, event.ID, targetID,
-		database.DeliveryStatusRetrying,
-	)
-
-	require.NoError(t, db.Unscoped().
-		Delete(&database.Delivery{}, "id = ?", d.ID).Error)
-
-	require.NoError(t, e.ExportUpdateDeliveryStatus(
-		db, &d, database.DeliveryStatusFailed,
-	))
-
-	assert.Equal(t, database.TargetTotals{TargetID: targetID},
-		targetTotals(t, db, targetID))
-}

internal/delivery/engine.go

@@ -531,11 +531,6 @@ func (e *Engine) processRetryTask(
 		return
 	}
 
-	// Set before anything below can fail the delivery: the failure is
-	// added to this target's totals.
-	d.EventID = task.EventID
-	d.TargetID = task.TargetID
-
 	if d.Status != database.DeliveryStatusRetrying {
 		e.log.Debug(
 			"skipping retry for delivery "+
@@ -567,6 +562,8 @@ func (e *Engine) processRetryTask(
 	}
 
 	target := buildTargetFromTask(task)
+	d.EventID = task.EventID
+	d.TargetID = task.TargetID
 	d.Event = event
 	d.Target = target
 
@@ -1557,9 +1554,8 @@ func (e *Engine) updateDeliveryStatus(
 	targetType database.TargetType,
 	status database.DeliveryStatus,
 ) error {
-	err := webhookDB.Transaction(func(tx *gorm.DB) error {
-		return writeDeliveryStatus(tx, d, status)
-	})
+	err := webhookDB.Model(d).
+		Update("status", status).Error
 	if err != nil {
 		return fmt.Errorf(
 			"updating delivery %s to status %s: %w",
@@ -1578,36 +1574,6 @@ func (e *Engine) updateDeliveryStatus(
 	return nil
 }
 
-// writeDeliveryStatus writes a delivery's new status. A delivery that
-// becomes delivered or failed also gets the time it finished, and is
-// added to its target's delivered or failed total. It is counted only
-// if the row was still there to update: retention may have deleted it
-// while the engine was working on it.
-func writeDeliveryStatus(
-	tx *gorm.DB,
-	d *database.Delivery,
-	status database.DeliveryStatus,
-) error {
-	if !status.Terminal() {
-		return tx.Model(d).Update("status", status).Error
-	}
-
-	res := tx.Model(d).Updates(map[string]any{
-		"status":      status,
-		"finished_at": time.Now(),
-	})
-	if res.Error != nil || res.RowsAffected == 0 {
-		return res.Error
-	}
-
-	add := database.TargetTotals{TargetID: d.TargetID, Delivered: 1}
-	if status == database.DeliveryStatusFailed {
-		add = database.TargetTotals{TargetID: d.TargetID, Failed: 1}
-	}
-
-	return database.AddTargetTotals(tx, add)
-}
-
 // settleStatus moves a delivery to its outcome status and reports a
 // failed write through bookkeepingFailed, which leaves the row
 // recoverable. It exists so the target call sites read as one

internal/delivery/engine_test.go

@@ -57,10 +57,7 @@ func testWebhookDB(t *testing.T) *gorm.DB {
 		&database.Event{},
 		&database.Delivery{},
 		&database.DeliveryResult{},
-		&database.EventTotals{},
-		&database.TargetTotals{},
 	))
-	require.NoError(t, db.Create(&database.EventTotals{}).Error)
 
 	return db
 }

internal/delivery/export_test.go

@@ -150,16 +150,6 @@ func (e *Engine) ExportDeliverSlack(
 	)
 }
 
-// ExportUpdateDeliveryStatus exposes updateDeliveryStatus. It passes no
-// target type, so no metric moves.
-func (e *Engine) ExportUpdateDeliveryStatus(
-	webhookDB *gorm.DB,
-	d *database.Delivery,
-	status database.DeliveryStatus,
-) error {
-	return e.updateDeliveryStatus(webhookDB, d, "", status)
-}
-
 // ExportProcessNewTask exposes processNewTask.
 func (e *Engine) ExportProcessNewTask(
 	ctx context.Context, task *Task,

internal/delivery/terminal_state_test.go

@@ -418,38 +418,6 @@ func TestProcessRetryTask_TargetDeleted_MakesNoAttempt(
 	assert.Zero(t, s.Engine.ExportInflightHeld())
 }
 
-// TestProcessRetryTask_TargetDeleted_CountsFailureOnTarget verifies
-// that the failure of a retry abandoned because its target is gone is
-// added to that target's own totals, not to a row with no target.
-func TestProcessRetryTask_TargetDeleted_CountsFailureOnTarget(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	s := newISetup(t)
-
-	var hits atomic.Int64
-
-	task, targetID := tRetryChainSetup(
-		t, s, "gone-counted", &hits,
-	)
-
-	require.NoError(t, s.MainDB.Delete(
-		&database.Target{}, "id = ?", targetID,
-	).Error)
-
-	s.Engine.ExportProcessRetryTask(
-		context.Background(), &task,
-	)
-
-	var rows []database.TargetTotals
-
-	require.NoError(t, s.WebhookDB.Find(&rows).Error)
-	assert.Equal(t, []database.TargetTotals{
-		{TargetID: targetID, Failed: 1},
-	}, rows)
-}
-
 // TestProcessRetryTask_TargetPresent_StillDelivers is the guard's
 // mutation check: a liveness check that refused every retry would pass
 // the test above and break every retry there is.

internal/handlers/auth.go

@@ -36,7 +36,7 @@ func (h *Handlers) HandleLoginSubmit() http.HandlerFunc {
 		err := r.ParseForm()
 		if err != nil {
 			h.log.Error("failed to parse form", "error", err)
-			http.Error(w, "Bad request", http.StatusBadRequest)
+			h.renderError(w, r, http.StatusBadRequest)
 
 			return
 		}
@@ -166,11 +166,7 @@ func (h *Handlers) authenticateUser(
 
 	valid, err := database.VerifyPassword(password, user.Password)
 	if err != nil {
-		h.log.Error("failed to verify password", "error", err)
-		http.Error(
-			w, "Internal server error",
-			http.StatusInternalServerError,
-		)
+		h.serverError(w, r, "failed to verify password", err)
 
 		return user, err
 	}
@@ -242,24 +238,14 @@ func (h *Handlers) createAuthenticatedSession(
 ) error {
 	oldSess, err := h.session.Get(r)
 	if err != nil {
-		h.log.Error("failed to get session", "error", err)
-		http.Error(
-			w, "Internal server error",
-			http.StatusInternalServerError,
-		)
+		h.serverError(w, r, "failed to get session", err)
 
 		return err
 	}
 
 	sess, err := h.session.Regenerate(r, w, oldSess)
 	if err != nil {
-		h.log.Error(
-			"failed to regenerate session", "error", err,
-		)
-		http.Error(
-			w, "Internal server error",
-			http.StatusInternalServerError,
-		)
+		h.serverError(w, r, "failed to regenerate session", err)
 
 		return err
 	}
@@ -268,11 +254,7 @@ func (h *Handlers) createAuthenticatedSession(
 
 	err = h.session.Save(r, w, sess)
 	if err != nil {
-		h.log.Error("failed to save session", "error", err)
-		http.Error(
-			w, "Internal server error",
-			http.StatusInternalServerError,
-		)
+		h.serverError(w, r, "failed to save session", err)
 
 		return err
 	}

internal/handlers/delivery_replay.go

@@ -105,9 +105,7 @@ func (h *Handlers) HandleDeliveryReplay() http.HandlerFunc {
 		// middleware, which runs before CSRF parses the form.
 		err := r.ParseForm()
 		if err != nil {
-			http.Error(
-				w, "Bad request", http.StatusBadRequest,
-			)
+			h.renderError(w, r, http.StatusBadRequest)
 
 			return
 		}
@@ -124,14 +122,14 @@ func (h *Handlers) replayDelivery(
 	webhook database.Webhook,
 ) {
 	if !h.dbMgr.DBExists(webhook.ID) {
-		http.NotFound(w, r)
+		h.renderError(w, r, http.StatusNotFound)
 
 		return
 	}
 
 	webhookDB, err := h.dbMgr.GetDB(webhook.ID)
 	if err != nil {
-		h.serverError(w, "failed to get webhook database", err)
+		h.serverError(w, r, "failed to get webhook database", err)
 
 		return
 	}
@@ -173,7 +171,7 @@ func (h *Handlers) loadReplaySource(
 			&original, "id = ?", chi.URLParam(r, "deliveryID"),
 		).Error
 	if err != nil {
-		http.NotFound(w, r)
+		h.renderError(w, r, http.StatusNotFound)
 
 		return nil, false
 	}
@@ -195,7 +193,7 @@ func (h *Handlers) queueReplay(
 	)
 	if err != nil {
 		h.serverError(
-			w, "failed to count in-flight deliveries", err,
+			w, r, "failed to count in-flight deliveries", err,
 		)
 
 		return
@@ -212,7 +210,7 @@ func (h *Handlers) queueReplay(
 	err = webhookDB.
 		First(&event, "id = ?", original.EventID).Error
 	if err != nil {
-		h.serverError(w, "failed to load event for replay", err)
+		h.serverError(w, r, "failed to load event for replay", err)
 
 		return
 	}
@@ -222,7 +220,7 @@ func (h *Handlers) queueReplay(
 	)
 	if err != nil {
 		h.serverError(
-			w, "failed to create replay delivery", err,
+			w, r, "failed to create replay delivery", err,
 		)
 
 		return
@@ -299,9 +297,8 @@ func countInFlightDeliveries(
 	return count, err
 }
 
-// createReplayDelivery writes the new pending delivery row, adds it to
-// its target's totals in the same transaction, and returns the task
-// that carries it to the delivery engine.
+// createReplayDelivery writes the new pending delivery row and returns
+// the task that carries it to the delivery engine.
 //
 // The row is written with associations omitted, and neither Event nor
 // Target is populated on it: GORM's SaveBeforeAssociations would
@@ -320,16 +317,7 @@ func createReplayDelivery(
 		Status:   database.DeliveryStatusPending,
 	}
 
-	err := webhookDB.Transaction(func(tx *gorm.DB) error {
-		err := tx.Omit(clause.Associations).Create(dlv).Error
-		if err != nil {
-			return err
-		}
-
-		return database.AddTargetTotals(tx, database.TargetTotals{
-			TargetID: dlv.TargetID, Deliveries: 1,
-		})
-	})
+	err := webhookDB.Omit(clause.Associations).Create(dlv).Error
 	if err != nil {
 		return delivery.Task{}, err
 	}

internal/handlers/error_page_test.go

@@ -0,0 +1,53 @@
+package handlers_test
+
+import (
+	"context"
+	"html/template"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"sneak.berlin/go/webhooker/internal/handlers"
+)
+
+// TestErrorPage_RenderFailureKeepsStatus proves that an error page
+// which cannot render answers with the status it was reporting, as
+// plain text, and is not attempted again: a page whose own render
+// fails reaches the error page, and the error page failing as well
+// ends there with the 500.
+func TestErrorPage_RenderFailureKeepsStatus(t *testing.T) {
+	t.Parallel()
+
+	var h *handlers.Handlers
+
+	app := newTestApp(t, &h)
+	app.RequireStart()
+
+	t.Cleanup(app.RequireStop)
+
+	// .Status is an int, so asking it for a field fails the render.
+	failing := `{{.Status.Missing}}`
+	h.AddTemplateForTest("error.html", template.Must(
+		template.New("error").Parse(failing),
+	))
+	h.AddTemplateForTest("failing.html", template.Must(
+		template.New("failing").Parse(`{{.Data.Missing}}`),
+	))
+
+	req := httptest.NewRequestWithContext(
+		context.Background(), http.MethodGet, "/", nil,
+	)
+
+	w := httptest.NewRecorder()
+	h.HandleErrorPage(http.StatusNotFound).ServeHTTP(w, req)
+
+	assert.Equal(t, http.StatusNotFound, w.Code)
+	assert.Equal(t, "Not Found\n", w.Body.String())
+
+	w = httptest.NewRecorder()
+	h.RenderTemplateForTest(w, req, "failing.html", 0)
+
+	assert.Equal(t, http.StatusInternalServerError, w.Code)
+	assert.Equal(t, "Internal Server Error\n", w.Body.String())
+}

internal/handlers/event_body.go

@@ -52,7 +52,7 @@ func (h *Handlers) HandleEventBodyDownload() http.HandlerFunc {
 		// steered by a client.
 		eventID, err := uuid.Parse(chi.URLParam(r, "eventID"))
 		if err != nil {
-			http.NotFound(w, r)
+			h.renderError(w, r, http.StatusNotFound)
 
 			return
 		}
@@ -103,21 +103,21 @@ func (h *Handlers) serveEventBody(
 	eventID string,
 ) {
 	if !h.dbMgr.DBExists(webhook.ID) {
-		http.NotFound(w, r)
+		h.renderError(w, r, http.StatusNotFound)
 
 		return
 	}
 
 	webhookDB, err := h.dbMgr.GetDB(webhook.ID)
 	if err != nil {
-		h.serverError(w, "failed to get webhook database", err)
+		h.serverError(w, r, "failed to get webhook database", err)
 
 		return
 	}
 
 	body, found, err := eventBody(webhookDB, webhook.ID, eventID)
 	if err != nil {
-		h.serverError(w, "failed to read event body", err)
+		h.serverError(w, r, "failed to read event body", err)
 
 		return
 	}
@@ -130,7 +130,7 @@ func (h *Handlers) serveEventBody(
 	// row and the whole body is served, or it does not and the
 	// response is a clean 404.
 	if !found {
-		http.NotFound(w, r)
+		h.renderError(w, r, http.StatusNotFound)
 
 		return
 	}

internal/handlers/event_resubmit.go

@@ -99,7 +99,7 @@ func (h *Handlers) HandleEventResubmit() http.HandlerFunc {
 		// middleware, which runs before CSRF parses the form.
 		err := r.ParseForm()
 		if err != nil {
-			http.Error(w, "Bad request", http.StatusBadRequest)
+			h.renderError(w, r, http.StatusBadRequest)
 
 			return
 		}
@@ -120,20 +120,20 @@ func (h *Handlers) resubmitEvent(
 	// alphabet rather than from the request.
 	eventID, err := uuid.Parse(chi.URLParam(r, "eventID"))
 	if err != nil {
-		http.NotFound(w, r)
+		h.renderError(w, r, http.StatusNotFound)
 
 		return
 	}
 
 	if !h.dbMgr.DBExists(webhook.ID) {
-		http.NotFound(w, r)
+		h.renderError(w, r, http.StatusNotFound)
 
 		return
 	}
 
 	webhookDB, err := h.dbMgr.GetDB(webhook.ID)
 	if err != nil {
-		h.serverError(w, "failed to get webhook database", err)
+		h.serverError(w, r, "failed to get webhook database", err)
 
 		return
 	}
@@ -147,7 +147,7 @@ func (h *Handlers) resubmitEvent(
 		webhookDB, webhook.ID, eventID.String(),
 	)
 	if err != nil {
-		h.serverError(w, "failed to load event to resubmit", err)
+		h.serverError(w, r, "failed to load event to resubmit", err)
 
 		return
 	}
@@ -155,7 +155,7 @@ func (h *Handlers) resubmitEvent(
 	// A miss is a 404 whether the event was reaped, belongs to
 	// another webhook, or never existed.
 	if !found {
-		http.NotFound(w, r)
+		h.renderError(w, r, http.StatusNotFound)
 
 		return
 	}
@@ -207,7 +207,7 @@ func (h *Handlers) queueResubmit(
 	// inactive one is skipped rather than refused.
 	targets, err := h.loadActiveTargets(webhook.ID)
 	if err != nil {
-		h.serverError(w, "failed to query targets", err)
+		h.serverError(w, r, "failed to query targets", err)
 
 		return
 	}
@@ -225,7 +225,7 @@ func (h *Handlers) queueResubmit(
 		targets,
 	)
 	if err != nil {
-		h.serverError(w, "failed to store resubmitted event", err)
+		h.serverError(w, r, "failed to store resubmitted event", err)
 
 		return
 	}

internal/handlers/export_test.go

@@ -1,12 +1,12 @@
 package handlers
 
 import (
+	"context"
 	"html/template"
 	"log/slog"
 	"net/http"
-	"time"
+	"net/http/httptest"
 
-	"gorm.io/gorm"
 	"sneak.berlin/go/webhooker/internal/database"
 )
 
@@ -65,33 +65,18 @@ func (s *Handlers) LoadEventLogViewsForTest(
 	page int,
 ) []EventLogView {
 	views, _, _ := s.loadEventsWithDeliveries(
-		w, webhook, nil, page,
+		w, newRequestForTest(), webhook, nil, page,
 	)
 
 	return views
 }
 
-// WebhookStatsForTest returns the figures the statistics pane on a
-// webhook's page shows, from the webhook's entrypoints and targets
-// loaded as that page loads them.
-func (s *Handlers) WebhookStatsForTest(webhookID string) *WebhookStats {
-	var entrypoints []database.Entrypoint
-
-	s.db.DB().Where("webhook_id = ?", webhookID).Find(&entrypoints)
-
-	var targets []database.Target
-
-	s.db.DB().Where("webhook_id = ?", webhookID).Find(&targets)
-
-	return s.loadWebhookStats(webhookID, entrypoints, targets)
-}
-
-// FinishedByTargetForTest exposes finishedByTarget for use in the
-// handlers_test package.
-func FinishedByTargetForTest(
-	webhookDB *gorm.DB, since time.Time,
-) ([]TargetFinished, error) {
-	return finishedByTarget(webhookDB, since)
+// newRequestForTest is the request the helpers here pass on for
+// callers that have none: it is used only to render the error page.
+func newRequestForTest() *http.Request {
+	return httptest.NewRequestWithContext(
+		context.Background(), http.MethodGet, "/", nil,
+	)
 }
 
 // AddTemplateForTest registers a template under a page name so that
@@ -147,5 +132,5 @@ func (s *Handlers) BuildDatabaseTargetConfigForTest(
 	w http.ResponseWriter,
 	expiry string,
 ) (string, error) {
-	return s.buildDatabaseTargetConfig(w, expiry)
+	return s.buildDatabaseTargetConfig(w, newRequestForTest(), expiry)
 }

internal/handlers/handlers.go

@@ -91,22 +91,18 @@ type Handlers struct {
 
 // parsePageTemplate parses a page-specific template set from the
 // embedded FS. Each page template is combined with the shared
-// base, htmlheader, and navbar templates, and with any further files
-// the page includes. The page file must be listed first so that its
-// root action ({{template "base" .}}) becomes the template set's entry
-// point.
-func parsePageTemplate(
-	pageFile string, included ...string,
-) *template.Template {
-	files := append([]string{
+// base, htmlheader, and navbar templates. The page file must be
+// listed first so that its root action ({{template "base" .}})
+// becomes the template set's entry point.
+func parsePageTemplate(pageFile string) *template.Template {
+	return template.Must(
+		template.ParseFS(
+			templates.Templates,
 			pageFile,
 			"base.html",
 			"htmlheader.html",
 			"navbar.html",
-	}, included...)
-
-	return template.Must(
-		template.ParseFS(templates.Templates, files...),
+		),
 	)
 }
 
@@ -135,10 +131,11 @@ func New(
 		"profile.html":       parsePageTemplate("profile.html"),
 		"sources_list.html":  parsePageTemplate("sources_list.html"),
 		"sources_new.html":   parsePageTemplate("sources_new.html"),
-		"source_detail.html": parsePageTemplate("source_detail.html", "webhook_stats.html"),
+		"source_detail.html": parsePageTemplate("source_detail.html"),
 		"source_edit.html":   parsePageTemplate("source_edit.html"),
 		"source_logs.html":   parsePageTemplate("source_logs.html"),
 		"target_edit.html":   parsePageTemplate("target_edit.html"),
+		"error.html":         parsePageTemplate("error.html"),
 	}
 
 	lc.Append(fx.Hook{
@@ -150,6 +147,15 @@ func New(
 	return s, nil
 }
 
+// HandleErrorPage returns a handler that answers every request with
+// the error page for status. The router uses it for unknown paths and
+// the CSRF middleware for a refused form.
+func (s *Handlers) HandleErrorPage(status int) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		s.renderError(w, r, status)
+	}
+}
+
 func (s *Handlers) respondJSON(
 	w http.ResponseWriter,
 	_ *http.Request,
@@ -167,15 +173,76 @@ func (s *Handlers) respondJSON(
 	}
 }
 
-// serverError logs an error and sends a 500 response.
+// serverError logs an error and answers with the 500 error page.
 func (s *Handlers) serverError(
-	w http.ResponseWriter, msg string, err error,
+	w http.ResponseWriter, r *http.Request, msg string, err error,
 ) {
 	s.log.Error(msg, "error", err)
-	http.Error(
-		w, "Internal server error",
-		http.StatusInternalServerError,
-	)
+	s.renderError(w, r, http.StatusInternalServerError)
+}
+
+// renderError answers with status and the error page: the normal
+// layout, one fixed line explaining the status, and a link back to the
+// webhook list, or to sign-in when nobody is signed in.
+//
+// It renders the page itself rather than through renderTemplate,
+// whose own failure comes here. If the error page cannot render
+// either, the answer is the same status in plain text: never a second
+// attempt, and never a different status.
+func (s *Handlers) renderError(
+	w http.ResponseWriter,
+	r *http.Request,
+	status int,
+) {
+	// The page names the signed-in user, and some error pages are
+	// served outside the routes where NoCache runs.
+	w.Header().Set("Cache-Control", "no-store")
+
+	data := s.pageData(r, map[string]any{
+		"Status":     status,
+		"StatusText": http.StatusText(status),
+		"Message":    errorPageText(status),
+	})
+
+	var buf bytes.Buffer
+
+	err := s.templates["error.html"].Execute(&buf, data)
+	if err != nil {
+		s.log.Error("failed to render error page", "error", err)
+		http.Error(w, http.StatusText(status), status)
+
+		return
+	}
+
+	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+	w.WriteHeader(status)
+
+	_, err = buf.WriteTo(w)
+	if err != nil {
+		s.log.Error("failed to write error page", "error", err)
+	}
+}
+
+// errorPageText is the line the error page shows for status. It is
+// fixed per status, so the page tells the reader no more than the
+// plain-text answers it replaced did.
+func errorPageText(status int) string {
+	switch status {
+	case http.StatusBadRequest:
+		return "The request could not be read."
+	case http.StatusForbidden:
+		return "The request was refused. If it came from a form " +
+			"left open for a long time, reload the page and try " +
+			"again."
+	case http.StatusNotFound:
+		return "There is nothing here. It may have been deleted, " +
+			"or the address may be wrong."
+	case http.StatusServiceUnavailable:
+		return "The server is busy. Please try again in a moment."
+	default: // http.StatusInternalServerError
+		return "Something went wrong on the server. Please try " +
+			"again."
+	}
 }
 
 // UserInfo represents user information for templates
@@ -228,14 +295,17 @@ func (s *Handlers) renderTemplate(
 			"template not found",
 			"template", pageTemplate,
 		)
-		http.Error(
-			w, "Internal server error",
-			http.StatusInternalServerError,
-		)
+		s.renderError(w, r, http.StatusInternalServerError)
 
 		return
 	}
 
+	s.executeTemplate(w, r, tmpl, s.pageData(r, data))
+}
+
+// pageData adds the fields the shared layout renders to a page's own
+// data.
+func (s *Handlers) pageData(r *http.Request, data any) any {
 	userInfo := s.getUserInfo(r)
 	csrfToken := middleware.CSRFToken(r)
 
@@ -249,19 +319,16 @@ func (s *Handlers) renderTemplate(
 		m["User"] = userInfo
 		m["CSRFToken"] = csrfToken
 		m["Version"] = version
-		s.executeTemplate(w, tmpl, m)
 
-		return
+		return m
 	}
 
-	wrapper := templateDataWrapper{
+	return templateDataWrapper{
 		User:      userInfo,
 		CSRFToken: csrfToken,
 		Version:   version,
 		Data:      data,
 	}
-
-	s.executeTemplate(w, tmpl, wrapper)
 }
 
 // executeTemplate renders the template into a buffer and writes to
@@ -274,6 +341,7 @@ func (s *Handlers) renderTemplate(
 // this reason.
 func (s *Handlers) executeTemplate(
 	w http.ResponseWriter,
+	r *http.Request,
 	tmpl *template.Template,
 	data any,
 ) {
@@ -284,10 +352,7 @@ func (s *Handlers) executeTemplate(
 		s.log.Error(
 			"failed to execute template", "error", err,
 		)
-		http.Error(
-			w, "Internal server error",
-			http.StatusInternalServerError,
-		)
+		s.renderError(w, r, http.StatusInternalServerError)
 
 		return
 	}

internal/handlers/handlers_test.go

@@ -307,10 +307,14 @@ func TestRenderTemplateMidRenderErrorSendsNoPartialBody(t *testing.T) {
 		t, http.StatusInternalServerError, w.Code,
 		"a failed render must report a 500",
 	)
-	assert.Equal(
-		t, "Internal server error\n", w.Body.String(),
+	assert.NotContains(
+		t, w.Body.String(), partialPageMarker,
 		"the response must carry no part of the aborted page",
 	)
+	assert.Contains(
+		t, w.Body.String(), "500 Internal Server Error",
+		"a failed render must answer with the error page",
+	)
 }
 
 func TestBuildDatabaseTargetConfig_Valid(t *testing.T) {

internal/handlers/profile.go

@@ -1,7 +1,6 @@
 package handlers
 
 import (
-	"context"
 	"net/http"
 
 	"github.com/go-chi/chi"
@@ -37,14 +36,14 @@ func (h *Handlers) HandlePasswordChange() http.HandlerFunc {
 		err := r.ParseForm()
 		if err != nil {
 			h.log.Error("failed to parse form", "error", err)
-			http.Error(w, "Bad request", http.StatusBadRequest)
+			h.renderError(w, r, http.StatusBadRequest)
 
 			return
 		}
 
 		successMessage, errorMessage, handled := h.applyPasswordChange(
-			r.Context(),
 			w,
+			r,
 			sessionUsername,
 			// PostFormValue, not FormValue: the credential must
 			// come from the body, never from the query string.
@@ -66,12 +65,12 @@ func (h *Handlers) HandlePasswordChange() http.HandlerFunc {
 // applyPasswordChange verifies the current password and, on success,
 // persists a fresh hash for the user, reusing the same helpers that
 // bootstrap the admin user. It returns the success and error messages
-// to display on the profile page. On an internal failure it writes a
-// 500 response itself and returns handled=false, signalling the caller
+// to display on the profile page. On an internal failure it writes the
+// error page itself and returns handled=false, signalling the caller
 // to stop without re-rendering the page.
 func (h *Handlers) applyPasswordChange(
-	ctx context.Context,
 	w http.ResponseWriter,
+	r *http.Request,
 	username, currentPassword, newPassword, confirmPassword string,
 ) (string, string, bool) {
 	// This endpoint verifies one password and hashes another, at
@@ -79,15 +78,10 @@ func (h *Handlers) applyPasswordChange(
 	// endpoint uses. The bound is per hash, not per endpoint: leaving
 	// this path outside it would leave a hole in it. The slot is held
 	// across both hashes.
-	release, ok := h.mw.BeginPasswordVerification(ctx)
+	release, ok := h.mw.BeginPasswordVerification(r.Context())
 	if !ok {
 		h.log.Warn("password verification capacity exhausted")
-		http.Error(
-			w,
-			"The server is busy verifying credentials. "+
-				"Please try again.",
-			http.StatusServiceUnavailable,
-		)
+		h.renderError(w, r, http.StatusServiceUnavailable)
 
 		return "", "", false
 	}
@@ -103,7 +97,7 @@ func (h *Handlers) applyPasswordChange(
 	).First(&user).Error
 	if err != nil {
 		h.serverError(
-			w, "failed to load user for password change", err,
+			w, r, "failed to load user for password change", err,
 		)
 
 		return "", "", false
@@ -113,7 +107,7 @@ func (h *Handlers) applyPasswordChange(
 		currentPassword, user.Password,
 	)
 	if err != nil {
-		h.serverError(w, "failed to verify password", err)
+		h.serverError(w, r, "failed to verify password", err)
 
 		return "", "", false
 	}
@@ -132,7 +126,7 @@ func (h *Handlers) applyPasswordChange(
 
 	hashedPassword, err := database.HashPassword(newPassword)
 	if err != nil {
-		h.serverError(w, "failed to hash new password", err)
+		h.serverError(w, r, "failed to hash new password", err)
 
 		return "", "", false
 	}
@@ -141,7 +135,7 @@ func (h *Handlers) applyPasswordChange(
 		"password", hashedPassword,
 	).Error
 	if err != nil {
-		h.serverError(w, "failed to update password", err)
+		h.serverError(w, r, "failed to update password", err)
 
 		return "", "", false
 	}
@@ -162,7 +156,7 @@ func (h *Handlers) profileOwnerOrDeny(
 ) (string, string, bool) {
 	requestedUsername := chi.URLParam(r, "username")
 	if requestedUsername == "" {
-		http.NotFound(w, r)
+		h.renderError(w, r, http.StatusNotFound)
 
 		return "", "", false
 	}
@@ -172,7 +166,7 @@ func (h *Handlers) profileOwnerOrDeny(
 	// unexpected retrieval error.
 	sess, err := h.session.Get(r)
 	if err != nil {
-		h.serverError(w, "failed to get session", err)
+		h.serverError(w, r, "failed to get session", err)
 
 		return "", "", false
 	}
@@ -180,10 +174,7 @@ func (h *Handlers) profileOwnerOrDeny(
 	sessionUsername, ok := h.session.GetUsername(sess)
 	if !ok {
 		h.log.Error("authenticated session missing username")
-		http.Error(
-			w, "Internal server error",
-			http.StatusInternalServerError,
-		)
+		h.renderError(w, r, http.StatusInternalServerError)
 
 		return "", "", false
 	}
@@ -191,17 +182,14 @@ func (h *Handlers) profileOwnerOrDeny(
 	sessionUserID, ok := h.session.GetUserID(sess)
 	if !ok {
 		h.log.Error("authenticated session missing user ID")
-		http.Error(
-			w, "Internal server error",
-			http.StatusInternalServerError,
-		)
+		h.renderError(w, r, http.StatusInternalServerError)
 
 		return "", "", false
 	}
 
 	// Only allow users to act on their own profile.
 	if requestedUsername != sessionUsername {
-		http.Error(w, "Forbidden", http.StatusForbidden)
+		h.renderError(w, r, http.StatusForbidden)
 
 		return "", "", false
 	}

internal/handlers/profile_test.go

@@ -128,7 +128,9 @@ func TestUserRoute_Unauthenticated_RedirectedByMiddleware(t *testing.T) {
 
 	var sess *session.Session
 
-	app := newTestApp(t, &log, &cfg, &sess)
+	var h *handlers.Handlers
+
+	app := newTestApp(t, &log, &cfg, &sess, &h)
 	app.RequireStart()
 
 	t.Cleanup(app.RequireStop)
@@ -139,7 +141,7 @@ func TestUserRoute_Unauthenticated_RedirectedByMiddleware(t *testing.T) {
 
 	router := chi.NewRouter()
 	router.Route("/user/{username}", func(r chi.Router) {
-		r.Use(mw.CSRF())
+		r.Use(mw.CSRF(h.HandleErrorPage(http.StatusForbidden)))
 		r.Use(mw.RequireAuth())
 		r.Get("/", func(w http.ResponseWriter, _ *http.Request) {
 			handlerReached = true

internal/handlers/source_management.go

@@ -149,13 +149,7 @@ func (h *Handlers) HandleSourceList() http.HandlerFunc {
 			"user_id = ?", userID,
 		).Order("created_at DESC").Find(&webhooks).Error
 		if err != nil {
-			h.log.Error(
-				"failed to list webhooks", "error", err,
-			)
-			http.Error(
-				w, "Internal server error",
-				http.StatusInternalServerError,
-			)
+			h.serverError(w, r, "failed to list webhooks", err)
 
 			return
 		}
@@ -249,9 +243,7 @@ func (h *Handlers) HandleSourceCreateSubmit() http.HandlerFunc {
 		// middleware, which runs before CSRF parses the form.
 		err := r.ParseForm()
 		if err != nil {
-			http.Error(
-				w, "Bad request", http.StatusBadRequest,
-			)
+			h.renderError(w, r, http.StatusBadRequest)
 
 			return
 		}
@@ -311,7 +303,7 @@ func (h *Handlers) createWebhookWithEntrypoint(
 
 	err := h.commitWebhook(webhook)
 	if err != nil {
-		h.serverError(w, "failed to create webhook", err)
+		h.serverError(w, r, "failed to create webhook", err)
 
 		return
 	}
@@ -388,7 +380,7 @@ func (h *Handlers) HandleSourceDetail() http.HandlerFunc {
 			"id = ? AND user_id = ?", sourceID, userID,
 		).First(&webhook).Error
 		if err != nil {
-			http.NotFound(w, r)
+			h.renderError(w, r, http.StatusNotFound)
 
 			return
 		}
@@ -420,7 +412,7 @@ func (h *Handlers) renderSourceDetail(
 	if h.dbMgr.DBExists(webhook.ID) {
 		webhookDB, err := h.dbMgr.GetDB(webhook.ID)
 		if err != nil {
-			h.serverError(w, "failed to get webhook database", err)
+			h.serverError(w, r, "failed to get webhook database", err)
 
 			return
 		}
@@ -429,7 +421,7 @@ func (h *Handlers) renderSourceDetail(
 			webhookDB, webhook.ID, singleHTTPTargetID(targets),
 		)
 		if err != nil {
-			h.serverError(w, "failed to load recent events", err)
+			h.serverError(w, r, "failed to load recent events", err)
 
 			return
 		}
@@ -457,7 +449,6 @@ func (h *Handlers) renderSourceDetail(
 		"Targets":     delivery.NewTargetViews(targets),
 		"Events":      events,
 		"BaseURL":     baseURL,
-		"Stats":       h.loadWebhookStats(webhook.ID, entrypoints, targets),
 	}
 
 	h.renderTemplate(w, r, "source_detail.html", data)
@@ -483,7 +474,7 @@ func (h *Handlers) HandleSourceEdit() http.HandlerFunc {
 			"id = ? AND user_id = ?", sourceID, userID,
 		).First(&webhook).Error
 		if err != nil {
-			http.NotFound(w, r)
+			h.renderError(w, r, http.StatusNotFound)
 
 			return
 		}
@@ -518,7 +509,7 @@ func (h *Handlers) HandleSourceEditSubmit() http.HandlerFunc {
 			"id = ? AND user_id = ?", sourceID, userID,
 		).First(&webhook).Error
 		if err != nil {
-			http.NotFound(w, r)
+			h.renderError(w, r, http.StatusNotFound)
 
 			return
 		}
@@ -527,9 +518,7 @@ func (h *Handlers) HandleSourceEditSubmit() http.HandlerFunc {
 		// middleware, which runs before CSRF parses the form.
 		err = r.ParseForm()
 		if err != nil {
-			http.Error(
-				w, "Bad request", http.StatusBadRequest,
-			)
+			h.renderError(w, r, http.StatusBadRequest)
 
 			return
 		}
@@ -583,7 +572,7 @@ func (h *Handlers) applyWebhookEdit(
 
 	err := h.db.DB().Save(webhook).Error
 	if err != nil {
-		h.serverError(w, "failed to update webhook", err)
+		h.serverError(w, r, "failed to update webhook", err)
 
 		return
 	}
@@ -613,7 +602,7 @@ func (h *Handlers) HandleSourceDelete() http.HandlerFunc {
 			"id = ? AND user_id = ?", sourceID, userID,
 		).First(&webhook).Error
 		if err != nil {
-			http.NotFound(w, r)
+			h.renderError(w, r, http.StatusNotFound)
 
 			return
 		}
@@ -640,7 +629,7 @@ func (h *Handlers) deleteWebhookResources(
 	// be removed by hand; deleted history cannot be recovered.
 	err := h.commitWebhookDeletion(&webhook)
 	if err != nil {
-		h.serverError(w, "failed to delete webhook", err)
+		h.serverError(w, r, "failed to delete webhook", err)
 
 		return
 	}
@@ -666,7 +655,7 @@ func (h *Handlers) deleteWebhookResources(
 		// redirecting as though everything succeeded: the file
 		// needs removing by hand, and the logged error names it.
 		h.serverError(
-			w, "failed to delete webhook event database", err,
+			w, r, "failed to delete webhook event database", err,
 		)
 
 		return
@@ -810,7 +799,7 @@ func (h *Handlers) ownedWebhook(
 		"id = ? AND user_id = ?", sourceID, userID,
 	).First(&webhook).Error
 	if err != nil {
-		http.NotFound(w, r)
+		h.renderError(w, r, http.StatusNotFound)
 
 		return database.Webhook{}, false
 	}
@@ -832,7 +821,7 @@ func (h *Handlers) HandleSourceLogs() http.HandlerFunc {
 			// Without the map every delivery renders through a
 			// zero redactor, so failing the page is the only
 			// safe answer.
-			h.serverError(w, "failed to load targets", err)
+			h.serverError(w, r, "failed to load targets", err)
 
 			return
 		}
@@ -840,7 +829,7 @@ func (h *Handlers) HandleSourceLogs() http.HandlerFunc {
 		page := h.parsePage(r)
 
 		evts, total, ok := h.loadEventsWithDeliveries(
-			w, webhook, targets, page,
+			w, r, webhook, targets, page,
 		)
 		if !ok {
 			return
@@ -950,6 +939,7 @@ func (h *Handlers) parsePage(r *http.Request) int {
 // caller must then render nothing further.
 func (h *Handlers) loadEventsWithDeliveries(
 	w http.ResponseWriter,
+	r *http.Request,
 	webhook database.Webhook,
 	targetMap map[string]eventLogTarget,
 	page int,
@@ -963,7 +953,7 @@ func (h *Handlers) loadEventsWithDeliveries(
 	webhookDB, err := h.dbMgr.GetDB(webhook.ID)
 	if err != nil {
 		h.serverError(
-			w, "failed to get webhook database", err,
+			w, r, "failed to get webhook database", err,
 		)
 
 		return nil, 0, false
@@ -1000,7 +990,7 @@ func (h *Handlers) loadEventsWithDeliveries(
 	)
 	if err != nil {
 		h.serverError(
-			w, "failed to load delivery attempts", err,
+			w, r, "failed to load delivery attempts", err,
 		)
 
 		return nil, 0, false
@@ -1009,7 +999,7 @@ func (h *Handlers) loadEventsWithDeliveries(
 	resubmits, err := resubmitCounts(webhookDB, eventIDs)
 	if err != nil {
 		h.serverError(
-			w, "failed to count event resubmissions", err,
+			w, r, "failed to count event resubmissions", err,
 		)
 
 		return nil, 0, false
@@ -1232,7 +1222,7 @@ func (h *Handlers) HandleEntrypointCreate() http.HandlerFunc {
 			"id = ? AND user_id = ?", sourceID, userID,
 		).First(&webhook).Error
 		if err != nil {
-			http.NotFound(w, r)
+			h.renderError(w, r, http.StatusNotFound)
 
 			return
 		}
@@ -1241,9 +1231,7 @@ func (h *Handlers) HandleEntrypointCreate() http.HandlerFunc {
 		// middleware, which runs before CSRF parses the form.
 		err = r.ParseForm()
 		if err != nil {
-			http.Error(
-				w, "Bad request", http.StatusBadRequest,
-			)
+			h.renderError(w, r, http.StatusBadRequest)
 
 			return
 		}
@@ -1259,7 +1247,7 @@ func (h *Handlers) HandleEntrypointCreate() http.HandlerFunc {
 
 		err = h.db.DB().Create(entrypoint).Error
 		if err != nil {
-			h.serverError(w, "failed to create entrypoint", err)
+			h.serverError(w, r, "failed to create entrypoint", err)
 
 			return
 		}
@@ -1290,7 +1278,7 @@ func (h *Handlers) HandleTargetCreate() http.HandlerFunc {
 			"id = ? AND user_id = ?", sourceID, userID,
 		).First(&webhook).Error
 		if err != nil {
-			http.NotFound(w, r)
+			h.renderError(w, r, http.StatusNotFound)
 
 			return
 		}
@@ -1299,9 +1287,7 @@ func (h *Handlers) HandleTargetCreate() http.HandlerFunc {
 		// middleware, which runs before CSRF parses the form.
 		err = r.ParseForm()
 		if err != nil {
-			http.Error(
-				w, "Bad request", http.StatusBadRequest,
-			)
+			h.renderError(w, r, http.StatusBadRequest)
 
 			return
 		}
@@ -1372,7 +1358,7 @@ func (h *Handlers) processTargetCreate(
 
 	err = h.db.DB().Create(target).Error
 	if err != nil {
-		h.serverError(w, "failed to create target", err)
+		h.serverError(w, r, "failed to create target", err)
 
 		return
 	}
@@ -1466,7 +1452,7 @@ func (h *Handlers) buildTargetConfig(
 	case database.TargetTypeSlack:
 		return h.buildSlackTargetConfig(w, r, in.URL)
 	case database.TargetTypeDatabase:
-		return h.buildDatabaseTargetConfig(w, in.Expiry)
+		return h.buildDatabaseTargetConfig(w, r, in.Expiry)
 	case database.TargetTypeLog:
 		return "", nil
 	default:
@@ -1516,7 +1502,7 @@ func (h *Handlers) buildHTTPTargetConfig(
 		return "", err
 	}
 
-	return marshalTargetConfig(w, delivery.HTTPTargetConfig{
+	return h.marshalTargetConfig(w, r, delivery.HTTPTargetConfig{
 		URL:     in.URL,
 		Headers: headers,
 		Timeout: timeout,
@@ -1538,7 +1524,7 @@ func (h *Handlers) buildSlackTargetConfig(
 		return "", err
 	}
 
-	return marshalTargetConfig(w, delivery.SlackTargetConfig{
+	return h.marshalTargetConfig(w, r, delivery.SlackTargetConfig{
 		WebhookURL: targetURL,
 	})
 }
@@ -1592,16 +1578,14 @@ func (h *Handlers) validateTargetURL(
 
 // marshalTargetConfig serialises a target configuration for storage,
 // writing a 500 itself if it cannot.
-func marshalTargetConfig(
+func (h *Handlers) marshalTargetConfig(
 	w http.ResponseWriter,
+	r *http.Request,
 	cfg any,
 ) (string, error) {
 	configBytes, err := json.Marshal(cfg)
 	if err != nil {
-		http.Error(
-			w, "Internal server error",
-			http.StatusInternalServerError,
-		)
+		h.serverError(w, r, "failed to encode target config", err)
 
 		return "", err
 	}
@@ -1617,6 +1601,7 @@ func marshalTargetConfig(
 // expiry yields an empty config (the keep-forever default).
 func (h *Handlers) buildDatabaseTargetConfig(
 	w http.ResponseWriter,
+	r *http.Request,
 	expiry string,
 ) (string, error) {
 	expiry = strings.TrimSpace(expiry)
@@ -1635,8 +1620,8 @@ func (h *Handlers) buildDatabaseTargetConfig(
 		return "", err
 	}
 
-	return marshalTargetConfig(
-		w, map[string]any{"expiry": expiry},
+	return h.marshalTargetConfig(
+		w, r, map[string]any{"expiry": expiry},
 	)
 }
 
@@ -1690,7 +1675,7 @@ func (h *Handlers) deleteChildResource(
 			"id = ? AND user_id = ?", sourceID, userID,
 		).First(&webhook).Error
 		if err != nil {
-			http.NotFound(w, r)
+			h.renderError(w, r, http.StatusNotFound)
 
 			return
 		}
@@ -1700,11 +1685,7 @@ func (h *Handlers) deleteChildResource(
 			childID, webhook.ID,
 		).Delete(model)
 		if result.Error != nil {
-			h.log.Error(errMsg, "error", result.Error)
-			http.Error(
-				w, "Internal server error",
-				http.StatusInternalServerError,
-			)
+			h.serverError(w, r, errMsg, result.Error)
 
 			return
 		}
@@ -1794,18 +1775,14 @@ func (h *Handlers) toggleChildResource(
 			"id = ? AND user_id = ?", sourceID, userID,
 		).First(&webhook).Error
 		if err != nil {
-			http.NotFound(w, r)
+			h.renderError(w, r, http.StatusNotFound)
 
 			return
 		}
 
 		err = toggleFn(webhook.ID, childID)
 		if err != nil {
-			h.log.Error(errMsg, "error", err)
-			http.Error(
-				w, "Internal server error",
-				http.StatusInternalServerError,
-			)
+			h.serverError(w, r, errMsg, err)
 
 			return
 		}

internal/handlers/target_edit.go

@@ -88,9 +88,7 @@ func (h *Handlers) HandleTargetEditSubmit() http.HandlerFunc {
 		// middleware, which runs before CSRF parses the form.
 		err := r.ParseForm()
 		if err != nil {
-			http.Error(
-				w, "Bad request", http.StatusBadRequest,
-			)
+			h.renderError(w, r, http.StatusBadRequest)
 
 			return
 		}
@@ -157,7 +155,7 @@ func (h *Handlers) applyTargetEdit(
 
 	err = h.db.DB().Save(target).Error
 	if err != nil {
-		h.serverError(w, "failed to update target", err)
+		h.serverError(w, r, "failed to update target", err)
 
 		return
 	}
@@ -220,7 +218,7 @@ func (h *Handlers) ownedTarget(
 		chi.URLParam(r, "targetID"), webhook.ID,
 	).First(&target).Error
 	if err != nil {
-		http.NotFound(w, r)
+		h.renderError(w, r, http.StatusNotFound)
 
 		return database.Webhook{}, nil, false
 	}

internal/handlers/webhook.go

@@ -88,14 +88,14 @@ func (h *Handlers) processWebhookRequest(
 
 	headersJSON, err := json.Marshal(r.Header)
 	if err != nil {
-		h.serverError(w, "failed to serialize headers", err)
+		h.receiverError(w, "failed to serialize headers", err)
 
 		return
 	}
 
 	targets, err := h.loadActiveTargets(entrypoint.WebhookID)
 	if err != nil {
-		h.serverError(w, "failed to query targets", err)
+		h.receiverError(w, "failed to query targets", err)
 
 		return
 	}
@@ -196,7 +196,7 @@ func (h *Handlers) createAndDeliverEvent(
 		targets,
 	)
 	if err != nil {
-		h.serverError(w, "failed to store webhook event", err)
+		h.receiverError(w, "failed to store webhook event", err)
 
 		return
 	}
@@ -204,6 +204,19 @@ func (h *Handlers) createAndDeliverEvent(
 	h.finishWebhookResponse(w, event, entrypoint, tasks)
 }
 
+// receiverError logs an error and answers the sender with a plain-text
+// 500. The receiver's answers are for programs, so it never sends the
+// error page the web UI uses.
+func (h *Handlers) receiverError(
+	w http.ResponseWriter, msg string, err error,
+) {
+	h.log.Error(msg, "error", err)
+	http.Error(
+		w, "Internal server error",
+		http.StatusInternalServerError,
+	)
+}
+
 // eventSource carries the fields a new event is built from. The
 // receiver fills it from the live request; the resubmit handler fills
 // it from a stored event. Both then go through createAndFanOut, so an
@@ -253,12 +266,11 @@ func requestEventSource(
 	}
 }
 
-// createAndFanOut writes the event and one pending delivery per target,
-// and adds them to the webhook's running totals, in a single
-// transaction, then hands the tasks to the delivery engine. It is the
-// only path by which an event and its deliveries are created, so a
-// resubmitted event is retried, SSRF-guarded and circuit-broken
-// exactly as a received one is.
+// createAndFanOut writes the event and one pending delivery per target
+// in a single transaction, then hands the tasks to the delivery
+// engine. It is the only path by which an event and its deliveries are
+// created, so a resubmitted event is retried, SSRF-guarded and
+// circuit-broken exactly as a received one is.
 //
 // The tasks are returned as well as queued, so a caller can report how
 // many targets the event went to.
@@ -298,13 +310,6 @@ func (h *Handlers) createAndFanOut(
 		return nil, nil, err
 	}
 
-	err = database.AddEventTotals(tx, database.EventTotals{Events: 1})
-	if err != nil {
-		tx.Rollback()
-
-		return nil, nil, err
-	}
-
 	err = tx.Commit().Error
 	if err != nil {
 		return nil, nil, fmt.Errorf(
@@ -363,9 +368,8 @@ func (h *Handlers) finishWebhookResponse(
 }
 
 // buildDeliveryTasks creates one pending delivery per target in the
-// transaction, adds each to its target's totals, and returns the tasks
-// for the delivery engine. The caller owns the transaction and rolls
-// it back on error.
+// transaction and returns the tasks for the delivery engine. The
+// caller owns the transaction and rolls it back on error.
 func buildDeliveryTasks(
 	tx *gorm.DB,
 	event *database.Event,
@@ -389,13 +393,6 @@ func buildDeliveryTasks(
 			)
 		}
 
-		err = database.AddTargetTotals(tx, database.TargetTotals{
-			TargetID: targets[i].ID, Deliveries: 1,
-		})
-		if err != nil {
-			return nil, err
-		}
-
 		tasks = append(tasks, delivery.Task{
 			DeliveryID:   dlv.ID,
 			EventID:      event.ID,

internal/handlers/webhook_stats.go

@@ -1,271 +0,0 @@
-package handlers
-
-import (
-	"fmt"
-	"time"
-
-	"gorm.io/gorm"
-	"sneak.berlin/go/webhooker/internal/database"
-)
-
-// The spans of the two recent windows the statistics pane reports on:
-// the last 10 minutes and the last 24 hours.
-const (
-	shortWindow = 10 * time.Minute
-	longWindow  = 24 * time.Hour
-)
-
-// percent turns a fraction into a percentage.
-const percent = 100
-
-// WebhookStats holds the figures in the statistics pane at the top of
-// the webhook page.
-type WebhookStats struct {
-	Entrypoints       int
-	ActiveEntrypoints int
-	Targets           int
-	ActiveTargets     int
-
-	// Lifetime counts every event, delivery and failure the webhook
-	// has had, and WithinRetention those still stored.
-	Lifetime        Counts
-	WithinRetention Counts
-
-	// InProgress counts the deliveries still pending or retrying.
-	InProgress int64
-
-	// LastEventAt is when the newest stored event arrived, or nil when
-	// none is stored.
-	LastEventAt *time.Time
-
-	Last10Minutes RecentWindow
-	Last24Hours   RecentWindow
-}
-
-// Counts holds a number of events, of deliveries and of failed
-// deliveries.
-type Counts struct {
-	Events     int64
-	Deliveries int64
-	Failures   int64
-}
-
-// RecentWindow holds what happened in one recent window: the events
-// received in it, and the deliveries that became delivered or failed in
-// it.
-type RecentWindow struct {
-	Events    int64
-	Delivered int64
-	Failed    int64
-}
-
-// TargetFinished is how many of one target's deliveries became
-// delivered, and how many failed, in a recent window.
-type TargetFinished struct {
-	TargetID  string
-	Delivered int64
-	Failed    int64
-}
-
-// FailurePercent is the share of the deliveries finished in the window
-// that failed, or a dash when none finished. Deliveries still pending
-// or retrying are not counted either way.
-func (w RecentWindow) FailurePercent() string {
-	finished := w.Delivered + w.Failed
-	if finished == 0 {
-		return "—"
-	}
-
-	return fmt.Sprintf(
-		"%.1f%%", percent*float64(w.Failed)/float64(finished),
-	)
-}
-
-// loadWebhookStats gathers the figures for the statistics pane from the
-// webhook's entrypoints and targets, as the page has already loaded
-// them, and from its event database. It returns nil, and logs why, when
-// the event database cannot be read.
-func (h *Handlers) loadWebhookStats(
-	webhookID string,
-	entrypoints []database.Entrypoint,
-	targets []database.Target,
-) *WebhookStats {
-	stats := &WebhookStats{
-		Entrypoints: len(entrypoints),
-		Targets:     len(targets),
-	}
-
-	for i := range entrypoints {
-		if entrypoints[i].Active {
-			stats.ActiveEntrypoints++
-		}
-	}
-
-	for i := range targets {
-		if targets[i].Active {
-			stats.ActiveTargets++
-		}
-	}
-
-	// Opening an event database that does not exist would create it,
-	// and it would hold nothing to count.
-	if !h.dbMgr.DBExists(webhookID) {
-		return stats
-	}
-
-	webhookDB, err := h.dbMgr.GetDB(webhookID)
-	if err == nil {
-		err = readEventStats(webhookDB, time.Now(), stats)
-	}
-
-	if err != nil {
-		h.log.Error(
-			"failed to read webhook statistics",
-			"webhook_id", webhookID,
-			"error", err,
-		)
-
-		return nil
-	}
-
-	return stats
-}
-
-// readEventStats fills in the figures that come from the webhook's
-// event database. None of them reads every stored row: the totals are
-// one row for the events and one per target for the deliveries, and
-// every other figure is read from an index, over only the rows it
-// counts.
-func readEventStats(
-	db *gorm.DB, now time.Time, stats *WebhookStats,
-) error {
-	err := readTotals(db, stats)
-	if err != nil {
-		return err
-	}
-
-	err = db.Model(&database.Delivery{}).
-		Where("status IN ?", []database.DeliveryStatus{
-			database.DeliveryStatusPending,
-			database.DeliveryStatusRetrying,
-		}).
-		Count(&stats.InProgress).Error
-	if err != nil {
-		return fmt.Errorf("counting deliveries in progress: %w", err)
-	}
-
-	var newest []time.Time
-
-	err = db.Model(&database.Event{}).
-		Order("created_at DESC").
-		Limit(1).
-		Pluck("created_at", &newest).Error
-	if err != nil {
-		return fmt.Errorf("reading newest event time: %w", err)
-	}
-
-	if len(newest) > 0 {
-		stats.LastEventAt = &newest[0]
-	}
-
-	stats.Last10Minutes, err = readRecentWindow(
-		db, now.Add(-shortWindow),
-	)
-	if err != nil {
-		return err
-	}
-
-	stats.Last24Hours, err = readRecentWindow(
-		db, now.Add(-longWindow),
-	)
-
-	return err
-}
-
-// readTotals fills in the lifetime and within-retention figures from
-// the running totals: the events' row, and the targets' rows summed.
-func readTotals(db *gorm.DB, stats *WebhookStats) error {
-	var events database.EventTotals
-
-	err := db.Take(&events).Error
-	if err != nil {
-		return fmt.Errorf("reading event totals: %w", err)
-	}
-
-	var targets []database.TargetTotals
-
-	err = db.Find(&targets).Error
-	if err != nil {
-		return fmt.Errorf("reading target totals: %w", err)
-	}
-
-	stats.Lifetime.Events = events.Events
-	stats.WithinRetention.Events = events.Events - events.EventsRemoved
-
-	for _, t := range targets {
-		stats.Lifetime.Deliveries += t.Deliveries
-		stats.Lifetime.Failures += t.Failed
-		stats.WithinRetention.Deliveries += t.Deliveries - t.DeliveriesRemoved
-		stats.WithinRetention.Failures += t.Failed - t.FailedRemoved
-	}
-
-	return nil
-}
-
-// readRecentWindow counts the events received, and the deliveries that
-// became delivered or failed, since the given time.
-func readRecentWindow(
-	db *gorm.DB, since time.Time,
-) (RecentWindow, error) {
-	var w RecentWindow
-
-	err := db.Model(&database.Event{}).
-		Where("created_at >= ?", since).
-		Count(&w.Events).Error
-	if err != nil {
-		return w, fmt.Errorf("counting recent events: %w", err)
-	}
-
-	byTarget, err := finishedByTarget(db, since)
-	if err != nil {
-		return w, err
-	}
-
-	for _, f := range byTarget {
-		w.Delivered += f.Delivered
-		w.Failed += f.Failed
-	}
-
-	return w, nil
-}
-
-// finishedByTarget counts, for each target, the deliveries that became
-// delivered and those that failed since the given time, in one query
-// over just that window of the deliveries' status index. A target with
-// neither is left out.
-func finishedByTarget(
-	db *gorm.DB, since time.Time,
-) ([]TargetFinished, error) {
-	var byTarget []TargetFinished
-
-	err := db.Model(&database.Delivery{}).
-		Select("target_id, "+
-			"count(CASE WHEN status = ? THEN 1 END) AS delivered, "+
-			"count(CASE WHEN status = ? THEN 1 END) AS failed",
-			database.DeliveryStatusDelivered,
-			database.DeliveryStatusFailed).
-		Where("status IN ? AND finished_at >= ?",
-			[]database.DeliveryStatus{
-				database.DeliveryStatusDelivered,
-				database.DeliveryStatusFailed,
-			}, since).
-		Group("target_id").
-		Find(&byTarget).Error
-	if err != nil {
-		return nil, fmt.Errorf(
-			"counting deliveries finished by target: %w", err,
-		)
-	}
-
-	return byTarget, nil
-}

internal/handlers/webhook_stats_test.go

@@ -1,474 +0,0 @@
-package handlers_test
-
-import (
-	"net/http"
-	"regexp"
-	"strings"
-	"testing"
-	"time"
-
-	"github.com/google/uuid"
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-	"go.uber.org/fx/fxtest"
-	"gorm.io/gorm"
-	"gorm.io/gorm/clause"
-	"sneak.berlin/go/webhooker/internal/config"
-	"sneak.berlin/go/webhooker/internal/database"
-	"sneak.berlin/go/webhooker/internal/handlers"
-	"sneak.berlin/go/webhooker/internal/logger"
-	"sneak.berlin/go/webhooker/internal/session"
-)
-
-// statsEntrypoint adds an entrypoint to a webhook and returns its path.
-func statsEntrypoint(
-	t *testing.T, db *database.Database, webhookID string, active bool,
-) string {
-	t.Helper()
-
-	ep := &database.Entrypoint{
-		WebhookID: webhookID,
-		Path:      uuid.New().String(),
-	}
-
-	require.NoError(t, db.DB().Omit(clause.Associations).Create(ep).Error)
-	require.NoError(t, db.DB().Model(ep).Update("active", active).Error)
-
-	return ep.Path
-}
-
-// statsDelivery returns an event's delivery to a target.
-func statsDelivery(
-	t *testing.T, webhookDB *gorm.DB, eventID, targetID string,
-) database.Delivery {
-	t.Helper()
-
-	var d database.Delivery
-
-	require.NoError(t, webhookDB.Where(
-		"event_id = ? AND target_id = ?", eventID, targetID,
-	).First(&d).Error)
-
-	return d
-}
-
-// statsFinish settles a delivery as the delivery engine does: its
-// final status and the time it finished, and one more on its target's
-// delivered or failed total, in one transaction.
-func statsFinish(
-	t *testing.T,
-	webhookDB *gorm.DB,
-	d database.Delivery,
-	status database.DeliveryStatus,
-	at time.Time,
-) {
-	t.Helper()
-
-	add := database.TargetTotals{TargetID: d.TargetID, Delivered: 1}
-	if status == database.DeliveryStatusFailed {
-		add = database.TargetTotals{TargetID: d.TargetID, Failed: 1}
-	}
-
-	require.NoError(t, webhookDB.Transaction(func(tx *gorm.DB) error {
-		err := tx.Model(&database.Delivery{}).
-			Where("id = ?", d.ID).
-			Updates(map[string]any{"status": status, "finished_at": at}).
-			Error
-		if err != nil {
-			return err
-		}
-
-		return database.AddTargetTotals(tx, add)
-	}))
-}
-
-// statsAge moves an event's arrival back to the given time.
-func statsAge(
-	t *testing.T, webhookDB *gorm.DB, eventID string, at time.Time,
-) {
-	t.Helper()
-
-	require.NoError(t, webhookDB.Model(&database.Event{}).
-		Where("id = ?", eventID).
-		Update("created_at", at).Error)
-}
-
-// statsTargetTotals reads a webhook database's target totals, keyed by
-// target.
-func statsTargetTotals(
-	t *testing.T, webhookDB *gorm.DB,
-) map[string]database.TargetTotals {
-	t.Helper()
-
-	var rows []database.TargetTotals
-
-	require.NoError(t, webhookDB.Find(&rows).Error)
-
-	byTarget := make(map[string]database.TargetTotals, len(rows))
-	for _, row := range rows {
-		byTarget[row.TargetID] = row
-	}
-
-	return byTarget
-}
-
-// statsHistory is the webhook seedStatsHistory builds: its event
-// database, its newest event, and its two active targets.
-type statsHistory struct {
-	webhook       *database.Webhook
-	webhookDB     *gorm.DB
-	newest        database.Event
-	first, second string
-}
-
-// seedStatsHistory builds the webhook the statistics test checks: one
-// day of retention, two entrypoints (one inactive) and three targets
-// (one inactive). Three events arrive through the receiver, and so
-// each has a delivery to the two active targets. The oldest event is
-// past retention, the middle one six hours old, the newest just in.
-// Their deliveries are settled as the delivery engine would, and a
-// replay adds a pending delivery to the oldest event.
-func seedStatsHistory(
-	t *testing.T,
-	h *handlers.Handlers,
-	sess *session.Session,
-	db *database.Database,
-	dbMgr *database.WebhookDBManager,
-) statsHistory {
-	t.Helper()
-
-	wh := &database.Webhook{
-		UserID: deleteTestUserID, Name: "stats", RetentionDays: 1,
-	}
-	require.NoError(t, db.DB().Omit(clause.Associations).Create(wh).Error)
-
-	path := statsEntrypoint(t, db, wh.ID, true)
-	statsEntrypoint(t, db, wh.ID, false)
-
-	first := seedConfiguredTarget(
-		t, db, wh.ID, database.TargetTypeHTTP,
-		`{"url":"`+replayTargetURL+`"}`,
-	)
-	second := seedTarget(t, db, wh.ID, database.TargetTypeLog)
-	inactive := seedTarget(t, db, wh.ID, database.TargetTypeLog)
-	require.NoError(t, db.DB().Model(inactive).
-		Update("active", false).Error)
-
-	router := receiverRouter(h)
-
-	for range 3 {
-		require.Equal(t, http.StatusOK, postReceiver(t, router, path))
-	}
-
-	webhookDB, err := dbMgr.GetDB(wh.ID)
-	require.NoError(t, err)
-
-	events := listEvents(t, webhookDB)
-	require.Len(t, events, 3)
-
-	oldest, middle, newest := events[0], events[1], events[2]
-	now := time.Now()
-
-	statsAge(t, webhookDB, oldest.ID, now.Add(-50*time.Hour))
-	statsAge(t, webhookDB, middle.ID, now.Add(-6*time.Hour))
-
-	oldestFailure := statsDelivery(t, webhookDB, oldest.ID, first.ID)
-	statsFinish(t, webhookDB, oldestFailure,
-		database.DeliveryStatusFailed, now.Add(-49*time.Hour))
-	statsFinish(t, webhookDB,
-		statsDelivery(t, webhookDB, oldest.ID, second.ID),
-		database.DeliveryStatusDelivered, now.Add(-49*time.Hour))
-	statsFinish(t, webhookDB,
-		statsDelivery(t, webhookDB, middle.ID, first.ID),
-		database.DeliveryStatusFailed, now.Add(-5*time.Hour))
-	statsFinish(t, webhookDB,
-		statsDelivery(t, webhookDB, middle.ID, second.ID),
-		database.DeliveryStatusFailed, now.Add(-time.Minute))
-	statsFinish(t, webhookDB,
-		statsDelivery(t, webhookDB, newest.ID, first.ID),
-		database.DeliveryStatusDelivered, now.Add(-2*time.Minute))
-
-	require.Equal(t, http.StatusSeeOther,
-		postReplay(t, h, sess, wh.ID, oldestFailure.ID).Code)
-
-	return statsHistory{
-		webhook:   wh,
-		webhookDB: webhookDB,
-		newest:    newest,
-		first:     first.ID,
-		second:    second.ID,
-	}
-}
-
-// statsPrune runs the real retention reaper until it has removed one
-// event from the webhook's database, then stops it.
-func statsPrune(
-	t *testing.T,
-	db *database.Database,
-	dbMgr *database.WebhookDBManager,
-	log *logger.Logger,
-	webhookDB *gorm.DB,
-) {
-	t.Helper()
-
-	lc := fxtest.NewLifecycle(t)
-	database.NewRetentionReaper(lc, database.RetentionReaperParams{
-		Config: &config.Config{
-			RetentionSweepInterval: 10 * time.Millisecond,
-		},
-		Database:  db,
-		DBManager: dbMgr,
-		Logger:    log,
-	})
-
-	lc.RequireStart()
-
-	require.Eventually(t, func() bool {
-		var totals database.EventTotals
-
-		err := webhookDB.Take(&totals).Error
-
-		return err == nil && totals.EventsRemoved == 1
-	}, 10*time.Second, 10*time.Millisecond)
-
-	lc.RequireStop()
-}
-
-// statsPane returns the text of the statistics pane in a rendered
-// webhook page, everything from its heading to the next heading on the
-// page, with the markup taken out and each run of space made one
-// space. A table then reads header by header and row by row, each
-// row's label followed by its figures in column order.
-func statsPane(t *testing.T, page string) string {
-	t.Helper()
-
-	_, pane, found := strings.Cut(page, ">Statistics</h2>")
-	require.True(t, found, "the page has no statistics pane")
-
-	pane, _, _ = strings.Cut(pane, "<h2")
-	pane = regexp.MustCompile(`<[^>]*>`).ReplaceAllString(pane, " ")
-
-	return strings.Join(strings.Fields(pane), " ")
-}
-
-// assertStatsTargets checks, for the history seedStatsHistory builds,
-// each target's totals and its deliveries finished in the last 24
-// hours. The first target has three deliveries and the replay, the
-// second three; the inactive target has none and so no row.
-func assertStatsTargets(t *testing.T, hist statsHistory) {
-	t.Helper()
-
-	first, second := hist.first, hist.second
-
-	assert.Equal(t, map[string]database.TargetTotals{
-		first: {TargetID: first, Deliveries: 4, Delivered: 1, Failed: 2},
-		second: {
-			TargetID: second, Deliveries: 3, Delivered: 1, Failed: 1,
-		},
-	}, statsTargetTotals(t, hist.webhookDB))
-
-	lastDay, err := handlers.FinishedByTargetForTest(
-		hist.webhookDB, time.Now().Add(-24*time.Hour),
-	)
-	require.NoError(t, err)
-	assert.ElementsMatch(t, []handlers.TargetFinished{
-		{TargetID: first, Delivered: 1, Failed: 1},
-		{TargetID: second, Failed: 1},
-	}, lastDay)
-}
-
-// assertStatsPaneAfterPrune checks the rendered statistics pane for the
-// history seedStatsHistory builds, once retention has removed the
-// oldest event: each figure after its label, in its column.
-func assertStatsPaneAfterPrune(
-	t *testing.T,
-	h *handlers.Handlers,
-	sess *session.Session,
-	hist statsHistory,
-) {
-	t.Helper()
-
-	pane := statsPane(t, renderSourceDetailPage(t, h, sess, hist.webhook.ID))
-	lastEvent := hist.newest.CreatedAt.Format("2006-01-02 15:04:05 UTC")
-
-	assert.Contains(t, pane, "Entrypoints 2 (1 active) "+
-		"Targets 3 (2 active) "+
-		"Deliveries in progress 1 "+
-		"Last event "+lastEvent+" "+
-		"Retention 1 day")
-	assert.Contains(t, pane, "Lifetime Within retention "+
-		"Events 3 2 "+
-		"Deliveries 7 4 "+
-		"Failures 3 2")
-	assert.Contains(t, pane, "Last 10 minutes Last 24 hours "+
-		"Events 1 2 "+
-		"Failures 1 2 "+
-		"Failure percentage 50.0% 66.7%")
-}
-
-// TestWebhookStats_EveryFigureAcrossRetentionPrune checks every figure
-// the statistics pane shows for the history seedStatsHistory builds,
-// and each target's totals and recent figures, before and after the
-// real retention reaper removes the oldest event.
-func TestWebhookStats_EveryFigureAcrossRetentionPrune(t *testing.T) {
-	t.Parallel()
-
-	var (
-		h     *handlers.Handlers
-		sess  *session.Session
-		db    *database.Database
-		dbMgr *database.WebhookDBManager
-		log   *logger.Logger
-	)
-
-	app := newTestApp(t, &h, &sess, &db, &dbMgr, &log)
-	app.RequireStart()
-
-	t.Cleanup(app.RequireStop)
-
-	hist := seedStatsHistory(t, h, sess, db, dbMgr)
-	first, second := hist.first, hist.second
-
-	stats := h.WebhookStatsForTest(hist.webhook.ID)
-	require.NotNil(t, stats)
-
-	assert.Equal(t, 2, stats.Entrypoints)
-	assert.Equal(t, 1, stats.ActiveEntrypoints)
-	assert.Equal(t, 3, stats.Targets)
-	assert.Equal(t, 2, stats.ActiveTargets)
-	assert.Equal(t, handlers.Counts{Events: 3, Deliveries: 7, Failures: 3},
-		stats.Lifetime)
-	assert.Equal(t, stats.Lifetime, stats.WithinRetention)
-	assert.Equal(t, int64(2), stats.InProgress)
-	require.NotNil(t, stats.LastEventAt)
-	assert.True(t, hist.newest.CreatedAt.Equal(*stats.LastEventAt))
-	assert.Equal(t, handlers.RecentWindow{
-		Events: 1, Delivered: 1, Failed: 1,
-	}, stats.Last10Minutes)
-	assert.Equal(t, handlers.RecentWindow{
-		Events: 2, Delivered: 1, Failed: 2,
-	}, stats.Last24Hours)
-	assert.Equal(t, "50.0%", stats.Last10Minutes.FailurePercent())
-	assert.Equal(t, "66.7%", stats.Last24Hours.FailurePercent())
-
-	assertStatsTargets(t, hist)
-
-	// Retention removes the oldest event with its three deliveries:
-	// the first target's failed one and the pending replay, and the
-	// second target's delivered one.
-	statsPrune(t, db, dbMgr, log, hist.webhookDB)
-
-	after := h.WebhookStatsForTest(hist.webhook.ID)
-	require.NotNil(t, after)
-
-	assert.Equal(t, stats.Lifetime, after.Lifetime)
-	assert.Equal(t, handlers.Counts{Events: 2, Deliveries: 4, Failures: 2},
-		after.WithinRetention)
-	assert.Equal(t, int64(1), after.InProgress)
-	assert.Equal(t, stats.LastEventAt, after.LastEventAt)
-	assert.Equal(t, stats.Last10Minutes, after.Last10Minutes)
-	assert.Equal(t, stats.Last24Hours, after.Last24Hours)
-
-	assert.Equal(t, map[string]database.TargetTotals{
-		first: {
-			TargetID: first, Deliveries: 4, Delivered: 1, Failed: 2,
-			DeliveriesRemoved: 2, FailedRemoved: 1,
-		},
-		second: {
-			TargetID: second, Deliveries: 3, Delivered: 1, Failed: 1,
-			DeliveriesRemoved: 1,
-		},
-	}, statsTargetTotals(t, hist.webhookDB))
-
-	assertStatsPaneAfterPrune(t, h, sess, hist)
-}
-
-// TestWebhookStats_PaneShowsRetentionPeriod checks that the statistics
-// pane itself, not only the line at the foot of the page, shows the
-// webhook's retention period, for a finite one and for forever.
-func TestWebhookStats_PaneShowsRetentionPeriod(t *testing.T) {
-	t.Parallel()
-
-	var (
-		h    *handlers.Handlers
-		sess *session.Session
-		db   *database.Database
-	)
-
-	app := newTestApp(t, &h, &sess, &db)
-	app.RequireStart()
-
-	t.Cleanup(app.RequireStop)
-
-	tests := []struct {
-		retentionDays int
-		want          string
-	}{
-		{30, "30 days"},
-		{database.RetentionForeverDays, "forever"},
-	}
-
-	for _, tt := range tests {
-		wh := &database.Webhook{
-			UserID:        deleteTestUserID,
-			Name:          "retention",
-			RetentionDays: tt.retentionDays,
-		}
-		require.NoError(t,
-			db.DB().Omit(clause.Associations).Create(wh).Error)
-
-		pane := statsPane(t, renderSourceDetailPage(t, h, sess, wh.ID))
-		assert.Contains(t, pane, "Retention "+tt.want)
-	}
-}
-
-// TestWebhookStats_WebhookWithNoEvents covers a webhook whose event
-// database has never been opened: every count is zero, the
-// percentages are a dash, and showing the page does not create the
-// database.
-func TestWebhookStats_WebhookWithNoEvents(t *testing.T) {
-	t.Parallel()
-
-	var (
-		h     *handlers.Handlers
-		sess  *session.Session
-		db    *database.Database
-		dbMgr *database.WebhookDBManager
-	)
-
-	app := newTestApp(t, &h, &sess, &db, &dbMgr)
-	app.RequireStart()
-
-	t.Cleanup(app.RequireStop)
-
-	wh := seedWebhook(t, db)
-
-	assert.Equal(t, &handlers.WebhookStats{}, h.WebhookStatsForTest(wh.ID))
-	assert.Equal(t, "—", handlers.RecentWindow{}.FailurePercent())
-
-	pane := statsPane(t, renderSourceDetailPage(t, h, sess, wh.ID))
-	assert.Contains(t, pane, "Last event none")
-	assert.Contains(t, pane, "Failure percentage — —")
-	assert.False(t, dbMgr.DBExists(wh.ID))
-}
-
-// TestRecentWindow_FailurePercent pins the percentage: failed
-// deliveries out of all that finished in the window.
-func TestRecentWindow_FailurePercent(t *testing.T) {
-	t.Parallel()
-
-	tests := []struct {
-		window handlers.RecentWindow
-		want   string
-	}{
-		{handlers.RecentWindow{}, "—"},
-		{handlers.RecentWindow{Events: 4}, "—"},
-		{handlers.RecentWindow{Delivered: 3, Failed: 1}, "25.0%"},
-		{handlers.RecentWindow{Failed: 2}, "100.0%"},
-		{handlers.RecentWindow{Delivered: 2}, "0.0%"},
-	}
-
-	for _, tt := range tests {
-		assert.Equal(t, tt.want, tt.window.FailurePercent(), tt.window)
-	}
-}

internal/middleware/csrf.go

@@ -19,7 +19,7 @@ func CSRFToken(r *http.Request) string {
 // key to sign a CSRF cookie and validates a masked token submitted via
 // the "csrf_token" form field (or the "X-CSRF-Token" header) on
 // POST/PUT/PATCH/DELETE requests. Requests with an invalid or missing
-// token receive a 403 Forbidden response.
+// token are logged and answered by forbidden, which must write the 403.
 //
 // The middleware detects the client-facing transport protocol
 // per-request via reqtls.IsTLS, the single TLS predicate the session
@@ -36,7 +36,9 @@ func CSRFToken(r *http.Request) string {
 // Two gorilla/csrf instances are maintained — one with Secure cookies
 // (for TLS) and one without (for plaintext HTTP) — because the
 // csrf.Secure option is set at creation time, not per-request.
-func (m *Middleware) CSRF() func(http.Handler) http.Handler {
+func (m *Middleware) CSRF(
+	forbidden http.Handler,
+) func(http.Handler) http.Handler {
 	csrfErrorHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		// CSRF is registered ahead of RequireAuth on every route
 		// group that uses it, so this WARN is reachable by an
@@ -57,7 +59,7 @@ func (m *Middleware) CSRF() func(http.Handler) http.Handler {
 			"remote_addr", r.RemoteAddr,
 			"reason", csrf.FailureReason(r),
 		)
-		http.Error(w, "Forbidden - invalid CSRF token", http.StatusForbidden)
+		forbidden.ServeHTTP(w, r)
 	})
 
 	key := m.session.GetKey()

internal/middleware/csrf_test.go

@@ -18,6 +18,12 @@ import (
 // csrfCookieName is the gorilla/csrf cookie name.
 const csrfCookieName = "_gorilla_csrf"
 
+// forbidden stands in for the error page the server hands CSRF to
+// answer a refused request with.
+func forbidden(w http.ResponseWriter, _ *http.Request) {
+	w.WriteHeader(http.StatusForbidden)
+}
+
 // csrfGetToken performs a GET request through the CSRF middleware
 // and returns the token and cookies.
 func csrfGetToken(
@@ -98,7 +104,7 @@ func TestCSRF_GETSetsToken(t *testing.T) {
 
 	var gotToken string
 
-	handler := m.CSRF()(http.HandlerFunc(
+	handler := m.CSRF(http.HandlerFunc(forbidden))(http.HandlerFunc(
 		func(_ http.ResponseWriter, r *http.Request) {
 			gotToken = middleware.CSRFToken(r)
 		},
@@ -120,7 +126,7 @@ func TestCSRF_POSTWithValidToken(t *testing.T) {
 	t.Parallel()
 
 	m, _ := testMiddleware(t, config.EnvironmentDev)
-	csrfMW := m.CSRF()
+	csrfMW := m.CSRF(http.HandlerFunc(forbidden))
 
 	getReq := httptest.NewRequestWithContext(
 		context.Background(),
@@ -152,7 +158,7 @@ func csrfPOSTWithoutTokenTest(
 	t.Helper()
 
 	m, _ := testMiddleware(t, env)
-	csrfMW := m.CSRF()
+	csrfMW := m.CSRF(http.HandlerFunc(forbidden))
 
 	// GET to establish the CSRF cookie
 	getHandler := csrfMW(http.HandlerFunc(
@@ -209,7 +215,7 @@ func TestCSRF_POSTWithInvalidToken(t *testing.T) {
 	t.Parallel()
 
 	m, _ := testMiddleware(t, config.EnvironmentDev)
-	csrfMW := m.CSRF()
+	csrfMW := m.CSRF(http.HandlerFunc(forbidden))
 
 	// GET to establish the CSRF cookie
 	getHandler := csrfMW(http.HandlerFunc(
@@ -265,7 +271,7 @@ func TestCSRF_GETDoesNotValidate(t *testing.T) {
 
 	var called bool
 
-	handler := m.CSRF()(http.HandlerFunc(
+	handler := m.CSRF(http.HandlerFunc(forbidden))(http.HandlerFunc(
 		func(_ http.ResponseWriter, _ *http.Request) {
 			called = true
 		},
@@ -328,7 +334,7 @@ func csrfTookStrictPath(
 	t.Helper()
 
 	m, _ := testMiddleware(t, env)
-	csrfMW := m.CSRF()
+	csrfMW := m.CSRF(http.HandlerFunc(forbidden))
 
 	newReq := func(method string) *http.Request {
 		r := httptest.NewRequestWithContext(
@@ -477,7 +483,7 @@ func TestCSRF_ProdMode_PlaintextHTTP_POSTWithValidToken(
 	t.Parallel()
 
 	m, _ := testMiddleware(t, config.EnvironmentProd)
-	csrfMW := m.CSRF()
+	csrfMW := m.CSRF(http.HandlerFunc(forbidden))
 
 	getReq := httptest.NewRequestWithContext(
 		context.Background(),
@@ -517,7 +523,7 @@ func TestCSRF_ProdMode_BehindProxy_POSTWithValidToken(
 	t.Parallel()
 
 	m, _ := testMiddleware(t, config.EnvironmentProd)
-	csrfMW := m.CSRF()
+	csrfMW := m.CSRF(http.HandlerFunc(forbidden))
 
 	getReq := httptest.NewRequestWithContext(
 		context.Background(),
@@ -562,7 +568,7 @@ func TestCSRF_ProdMode_DirectTLS_POSTWithValidToken(
 	t.Parallel()
 
 	m, _ := testMiddleware(t, config.EnvironmentProd)
-	csrfMW := m.CSRF()
+	csrfMW := m.CSRF(http.HandlerFunc(forbidden))
 
 	getReq := httptest.NewRequestWithContext(
 		context.Background(),

internal/middleware/logbound_test.go

@@ -260,7 +260,9 @@ func logSites() map[string]logSite {
 			) http.Handler {
 				t.Helper()
 
-				return m.CSRF()(unreachable(t))
+				return m.CSRF(http.HandlerFunc(forbidden))(
+					unreachable(t),
+				)
 			},
 			send:       postNoToken,
 			wantStatus: http.StatusForbidden,

internal/middleware/recoverer.go

@@ -109,7 +109,8 @@ func (w *recoverResponseWriter) Unwrap() http.ResponseWriter {
 
 // Recoverer returns middleware that turns a handler panic into one
 // structured ERROR record and a 500, rather than a dropped
-// connection.
+// connection. The 500 is page when page is not nil, and plain text
+// when it is nil or when page panics before writing anything.
 //
 // It replaces chi's middleware.Recoverer, which does neither on a
 // current Go release. chi v1.5.5's pretty-printer scans the stack for
@@ -138,7 +139,9 @@ func (w *recoverResponseWriter) Unwrap() http.ResponseWriter {
 // set before panicking, because a request that failed must not hand
 // the client a credential; every other header is left to http.Error.
 // See https://git.eeqj.de/sneak/webhooker/issues/193.
-func (s *Middleware) Recoverer() func(http.Handler) http.Handler {
+func (s *Middleware) Recoverer(
+	page http.Handler,
+) func(http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(
 			w http.ResponseWriter,
@@ -171,6 +174,14 @@ func (s *Middleware) Recoverer() func(http.Handler) http.Handler {
 
 				rw.Header().Del("Set-Cookie")
 
+				if page != nil {
+					s.servePage(rw, r, page)
+				}
+
+				if rw.committed {
+					return
+				}
+
 				http.Error(
 					rw,
 					http.StatusText(
@@ -185,6 +196,27 @@ func (s *Middleware) Recoverer() func(http.Handler) http.Handler {
 	}
 }
 
+// servePage answers with page. A panic in page itself is logged and
+// recovered here, so the Recoverer can still send its plain 500.
+func (s *Middleware) servePage(
+	w http.ResponseWriter,
+	r *http.Request,
+	page http.Handler,
+) {
+	defer func() {
+		rvr := recover()
+		if rvr != nil {
+			s.log.Error("error page panic",
+				"panic", logfield.Truncate(
+					fmt.Sprint(rvr), maxPanicValueBytes,
+				),
+			)
+		}
+	}()
+
+	page.ServeHTTP(w, r)
+}
+
 // logPanic writes the record. Every field it can grow is truncated to
 // a fixed budget, so MaxPanicLogLineBytes holds.
 //

internal/middleware/recoverer_test.go

@@ -76,7 +76,7 @@ func newRecovererProbe(
 	// Logging outside so the recovered 500 is the status it records.
 	router.Use(chimw.RequestID)
 	router.Use(m.Logging())
-	router.Use(m.Recoverer())
+	router.Use(m.Recoverer(nil))
 	router.Get("/probe", handler)
 
 	serverErrors := new(bytes.Buffer)
@@ -637,7 +637,7 @@ func TestRecovererKeepsResponseControllerWorking(t *testing.T) {
 
 	m, _ := capturingMiddleware(t)
 
-	handler := m.Recoverer()(http.HandlerFunc(
+	handler := m.Recoverer(nil)(http.HandlerFunc(
 		func(w http.ResponseWriter, _ *http.Request) {
 			_, _ = w.Write([]byte("chunk"))
 
@@ -672,3 +672,59 @@ func TestRecovererKeepsResponseControllerWorking(t *testing.T) {
 	assert.Equal(t, http.StatusOK, resp.StatusCode)
 	assert.Equal(t, "chunk", string(body))
 }
+
+// TestRecovererAnswersWithThePage covers a recoverer given a page:
+// the panic is logged as before, and the 500 is that page.
+func TestRecovererAnswersWithThePage(t *testing.T) {
+	t.Parallel()
+
+	m, logs := capturingMiddleware(t)
+
+	page := http.HandlerFunc(
+		func(w http.ResponseWriter, _ *http.Request) {
+			w.WriteHeader(http.StatusInternalServerError)
+			_, _ = w.Write([]byte("the error page"))
+		},
+	)
+
+	w := httptest.NewRecorder()
+	m.Recoverer(page)(http.HandlerFunc(panicProbe)).ServeHTTP(
+		w, httptest.NewRequestWithContext(
+			t.Context(), http.MethodGet, "/", nil,
+		),
+	)
+
+	assert.Equal(t, http.StatusInternalServerError, w.Code)
+	assert.Equal(t, "the error page", w.Body.String())
+	assert.Contains(t, logs.String(), `"msg":"handler panic"`)
+	assert.Contains(t, logs.String(), panicMarker)
+}
+
+// TestRecovererFallsBackWhenThePagePanics covers a page that panics
+// before writing anything: both panics are logged, and the client
+// still gets the plain 500.
+func TestRecovererFallsBackWhenThePagePanics(t *testing.T) {
+	t.Parallel()
+
+	m, logs := capturingMiddleware(t)
+
+	const pagePanic = "QQERRORPAGEPANICQQ"
+
+	page := http.HandlerFunc(
+		func(http.ResponseWriter, *http.Request) {
+			panic(pagePanic)
+		},
+	)
+
+	w := httptest.NewRecorder()
+	m.Recoverer(page)(http.HandlerFunc(panicProbe)).ServeHTTP(
+		w, httptest.NewRequestWithContext(
+			t.Context(), http.MethodGet, "/", nil,
+		),
+	)
+
+	assert.Equal(t, http.StatusInternalServerError, w.Code)
+	assert.Equal(t, "Internal Server Error\n", w.Body.String())
+	assert.Contains(t, logs.String(), panicMarker)
+	assert.Contains(t, logs.String(), pagePanic)
+}

internal/server/error_page_test.go

@@ -0,0 +1,220 @@
+package server_test
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"strconv"
+	"testing"
+
+	"github.com/getsentry/sentry-go"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"sneak.berlin/go/webhooker/internal/config"
+	"sneak.berlin/go/webhooker/internal/server"
+)
+
+// The link back the error page offers: to the webhook list for a
+// signed-in user, to sign-in for anyone else.
+const (
+	backToWebhooks = `<a href="/sources" class="btn-secondary">` +
+		`Back to webhooks</a>`
+	backToSignIn = `<a href="/pages/login" class="btn-primary">` +
+		`Sign in</a>`
+)
+
+// assertErrorPage checks that w is the error page for status, in the
+// normal layout, offering link.
+func assertErrorPage(
+	t *testing.T,
+	w *httptest.ResponseRecorder,
+	status int,
+	link string,
+) {
+	t.Helper()
+
+	body := w.Body.String()
+
+	assert.Equal(t, status, w.Code)
+	assert.Equal(
+		t, "text/html; charset=utf-8", w.Header().Get("Content-Type"),
+	)
+	assert.Equal(t, "no-store", w.Header().Get("Cache-Control"))
+	assert.Contains(t, body, `<nav class="app-bar"`)
+	assert.Contains(
+		t, body, strconv.Itoa(status)+" "+http.StatusText(status),
+	)
+	assert.Contains(t, body, link)
+}
+
+func TestErrorPage_DeletedWebhook(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+
+	userID, _ := env.seedUser(t, "owner", "somepassword")
+	cookies := env.authCookies(t, userID, "owner")
+
+	wh := env.seedWebhook(t, userID)
+	require.NoError(t, env.db.DB().Delete(wh).Error)
+
+	w := env.get("/source/"+wh.ID, cookies)
+
+	assertErrorPage(t, w, http.StatusNotFound, backToWebhooks)
+}
+
+func TestErrorPage_DeletedTarget(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+
+	userID, _ := env.seedUser(t, "owner", "somepassword")
+	cookies := env.authCookies(t, userID, "owner")
+
+	wh := env.seedWebhook(t, userID)
+	tgt := env.seedTarget(t, wh.ID)
+	require.NoError(t, env.db.DB().Delete(tgt).Error)
+
+	w := env.get(
+		"/source/"+wh.ID+"/targets/"+tgt.ID+"/edit", cookies,
+	)
+
+	assertErrorPage(t, w, http.StatusNotFound, backToWebhooks)
+}
+
+func TestErrorPage_UnknownPath(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+
+	userID, _ := env.seedUser(t, "owner", "somepassword")
+	cookies := env.authCookies(t, userID, "owner")
+
+	assertErrorPage(
+		t, env.get("/no-such-page", nil),
+		http.StatusNotFound, backToSignIn,
+	)
+
+	// Outside every route group there is no form token, so the
+	// page leaves out the logout form rather than offer one that
+	// would be refused.
+	w := env.get("/no-such-page", cookies)
+	assertErrorPage(t, w, http.StatusNotFound, backToWebhooks)
+	assert.NotContains(t, w.Body.String(), `action="/pages/logout"`)
+
+	// Inside a route group the page has a token, and logout works.
+	wh := env.seedWebhook(t, userID)
+	w = env.get("/source/"+wh.ID+"/no-such-page", cookies)
+	assertErrorPage(t, w, http.StatusNotFound, backToWebhooks)
+	assert.Contains(t, w.Body.String(), `action="/pages/logout"`)
+}
+
+func TestErrorPage_BadCSRFToken(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+
+	form := url.Values{}
+	form.Set("username", "someone")
+	form.Set("password", "irrelevant")
+	form.Set("csrf_token", "not-a-token")
+
+	assertErrorPage(
+		t, env.post("/pages/login", form, nil),
+		http.StatusForbidden, backToSignIn,
+	)
+
+	userID, _ := env.seedUser(t, "owner", "somepassword")
+	cookies := env.authCookies(t, userID, "owner")
+	wh := env.seedWebhook(t, userID)
+
+	edit := url.Values{}
+	edit.Set("name", "renamed")
+
+	assertErrorPage(
+		t, env.post("/source/"+wh.ID+"/edit", edit, cookies),
+		http.StatusForbidden, backToWebhooks,
+	)
+}
+
+// TestErrorPage_PanicOnAdminPage sends a panicking handler in an
+// admin page route group through the real router, with error
+// tracking on: the client gets the 500 error page, and the tracker
+// still gets the panic, once. The same panic outside the admin page
+// route groups keeps the plain 500.
+func TestErrorPage_PanicOnAdminPage(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+
+	transport := &captureTransport{}
+
+	opts := server.SentryClientOptionsForTest(
+		"https://public@sentry.invalid/1", "webhooker-test",
+	)
+	opts.Transport = transport
+
+	client, err := sentry.NewClient(opts)
+	require.NoError(t, err)
+
+	serve := func(router http.Handler, path string) *httptest.ResponseRecorder {
+		req := httptest.NewRequestWithContext(
+			sentry.SetHubOnContext(
+				context.Background(),
+				sentry.NewHub(client, sentry.NewScope()),
+			),
+			http.MethodGet, path, nil,
+		)
+
+		w := httptest.NewRecorder()
+		router.ServeHTTP(w, req)
+
+		return w
+	}
+
+	w := serve(
+		server.NewRouterWithPageProbeForTest(
+			env.log.Get(), env.cfg, env.mw, env.hnd,
+			true, panicProbeHandler,
+		),
+		server.PageProbePattern,
+	)
+	assertErrorPage(t, w, http.StatusInternalServerError, backToSignIn)
+
+	w = serve(
+		server.NewRouterWithProbeForTest(
+			env.log.Get(), env.cfg, env.mw, env.hnd,
+			true, panicProbeHandler,
+		),
+		server.ProbePattern,
+	)
+	assert.Equal(t, http.StatusInternalServerError, w.Code)
+	assert.Equal(t, "Internal Server Error\n", w.Body.String())
+
+	require.Len(t, transport.events, 2)
+
+	for _, event := range transport.events {
+		assert.Contains(t, marshalEvent(t, event), panicProbeMarker)
+	}
+}
+
+// TestErrorPage_ReceiverStaysPlain pins that the error page is for
+// the web UI only: a sender posting to an entrypoint that does not
+// exist still gets the plain-text answer.
+func TestErrorPage_ReceiverStaysPlain(t *testing.T) {
+	t.Parallel()
+
+	// newTestEnv leaves the receiver rate limit at zero, which
+	// refuses every request before it reaches the receiver.
+	env := newTestEnvWithConfig(t, &config.Config{
+		DataDir:           t.TempDir(),
+		Environment:       config.EnvironmentDev,
+		ReceiverRateLimit: 10,
+	})
+
+	w := env.post("/webhook/no-such-entrypoint", url.Values{}, nil)
+
+	assert.Equal(t, http.StatusNotFound, w.Code)
+	assert.Equal(t, "404 page not found\n", w.Body.String())
+}

internal/server/export_test.go

@@ -5,6 +5,7 @@ import (
 	"net/http"
 
 	"github.com/getsentry/sentry-go"
+	"github.com/go-chi/chi"
 	"sneak.berlin/go/webhooker/internal/config"
 	"sneak.berlin/go/webhooker/internal/handlers"
 	"sneak.berlin/go/webhooker/internal/middleware"
@@ -101,3 +102,39 @@ func NewRouterWithProbeForTest(
 
 	return s.router
 }
+
+// PageProbePattern is where NewRouterWithPageProbeForTest serves its
+// probe: inside the /pages route group, the admin page group a
+// request reaches without signing in.
+const PageProbePattern = "/pages/probe"
+
+// NewRouterWithPageProbeForTest is NewRouterWithProbeForTest with the
+// probe added to the /pages route group once SetupRoutes has built
+// it, so the probe runs behind that group's own middleware exactly as
+// the group's real routes do.
+func NewRouterWithPageProbeForTest(
+	log *slog.Logger,
+	cfg *config.Config,
+	mw *middleware.Middleware,
+	h *handlers.Handlers,
+	sentryEnabled bool,
+	probe http.HandlerFunc,
+) http.Handler {
+	s := &Server{
+		log:    log,
+		mw:     mw,
+		h:      h,
+		params: ServerParams{Config: cfg},
+	}
+	s.sentryEnabled.Store(sentryEnabled)
+	s.SetupRoutes()
+
+	for _, route := range s.router.Routes() {
+		pages, ok := route.SubRoutes.(chi.Router)
+		if ok && route.Pattern == "/pages/*" {
+			pages.Get("/probe", probe)
+		}
+	}
+
+	return s.router
+}

internal/server/routes.go

@@ -16,8 +16,8 @@ import (
 // submission while preventing abuse from oversized payloads.
 //
 // Every route group below installs MaxBodySize(maxFormBodySize) as
-// its FIRST middleware, ahead of both CSRF and RequireAuth. Both
-// orderings are deliberate.
+// its first middleware after the recoverer, ahead of both CSRF and
+// RequireAuth. Both orderings are deliberate.
 //
 // Ahead of CSRF because gorilla/csrf parses the form. The cap has to
 // be installed before anything reads the body, or the parse runs
@@ -46,6 +46,14 @@ const requestTimeout = 60 * time.Second
 // server's router.
 func (s *Server) SetupRoutes() {
 	s.router = chi.NewRouter()
+
+	// An unknown path gets the error page. Registered before the
+	// global middleware, because chi wraps a not-found handler in the
+	// middleware already on its router, which would then run twice.
+	// The route groups below wrap it in their own middleware the same
+	// way; running theirs twice is harmless.
+	s.router.NotFound(s.h.HandleErrorPage(http.StatusNotFound))
+
 	s.setupGlobalMiddleware()
 	s.setupRoutes()
 }
@@ -69,23 +77,33 @@ func (s *Server) setupGlobalMiddleware() {
 	// Panic recovery, deliberately here rather than first. It has to
 	// run inside every middleware that observes the response, so the
 	// 500 it writes is the status the access log records and the
-	// metrics count, and outside the sentryhttp handler below, whose
+	// metrics count, and outside the sentryhttp handler, whose
 	// Repanic option needs something further out to catch what it
 	// re-raises. chi's own middleware.Recoverer held the first slot
 	// until it was measured: on a current Go release it crashes
 	// inside its stack pretty-printer instead of recovering, so the
 	// connection dropped and the original panic was never reported.
 	// See https://git.eeqj.de/sneak/webhooker/issues/187.
-	s.router.Use(s.mw.Recoverer())
+	s.recoverPanics(s.router, nil)
+}
+
+// recoverPanics installs on r the recoverer, answering a panic with
+// page (a plain 500 when page is nil), and inside it the Sentry error
+// reporting (if SENTRY_DSN is set). Repanic is true so panics still
+// bubble up to the recoverer.
+//
+// Each admin page route group installs its own, with the error page,
+// as its first middleware. A panic there is logged, reported and
+// answered inside the group and never reaches the global recoverer,
+// which keeps the plain 500 for every other route.
+func (s *Server) recoverPanics(r chi.Router, page http.Handler) {
+	r.Use(s.mw.Recoverer(page))
 
-	// Sentry error reporting (if SENTRY_DSN is set). Repanic is
-	// true so panics still bubble up to the Recoverer middleware
-	// registered immediately above.
 	if s.sentryEnabled.Load() {
 		sentryHandler := sentryhttp.New(sentryhttp.Options{
 			Repanic: true,
 		})
-		s.router.Use(sentryHandler.Handle)
+		r.Use(sentryHandler.Handle)
 	}
 }
 
@@ -147,10 +165,13 @@ func (s *Server) setupRoutes() {
 
 func (s *Server) setupPageRoutes() {
 	s.router.Route("/pages", func(r chi.Router) {
+		s.recoverPanics(
+			r, s.h.HandleErrorPage(http.StatusInternalServerError),
+		)
 		// MaxBodySize precedes CSRF and RequireAuth deliberately;
 		// see maxFormBodySize for why, and for what it costs.
 		r.Use(s.mw.MaxBodySize(maxFormBodySize))
-		r.Use(s.mw.CSRF())
+		r.Use(s.mw.CSRF(s.h.HandleErrorPage(http.StatusForbidden)))
 		r.Use(s.mw.NoCache())
 
 		// The login POST carries no pre-emptive rate limiter. Behind
@@ -169,10 +190,13 @@ func (s *Server) setupPageRoutes() {
 
 func (s *Server) setupUserRoutes() {
 	s.router.Route("/user/{username}", func(r chi.Router) {
+		s.recoverPanics(
+			r, s.h.HandleErrorPage(http.StatusInternalServerError),
+		)
 		// MaxBodySize precedes CSRF and RequireAuth deliberately;
 		// see maxFormBodySize for why, and for what it costs.
 		r.Use(s.mw.MaxBodySize(maxFormBodySize))
-		r.Use(s.mw.CSRF())
+		r.Use(s.mw.CSRF(s.h.HandleErrorPage(http.StatusForbidden)))
 		r.Use(s.mw.NoCache())
 		r.Use(s.mw.RequireAuth())
 		r.Get("/", s.h.HandleProfile())
@@ -184,10 +208,13 @@ func (s *Server) setupUserRoutes() {
 
 func (s *Server) setupSourceRoutes() {
 	s.router.Route("/sources", func(r chi.Router) {
+		s.recoverPanics(
+			r, s.h.HandleErrorPage(http.StatusInternalServerError),
+		)
 		// MaxBodySize precedes CSRF and RequireAuth deliberately;
 		// see maxFormBodySize for why, and for what it costs.
 		r.Use(s.mw.MaxBodySize(maxFormBodySize))
-		r.Use(s.mw.CSRF())
+		r.Use(s.mw.CSRF(s.h.HandleErrorPage(http.StatusForbidden)))
 		r.Use(s.mw.NoCache())
 		r.Use(s.mw.RequireAuth())
 		r.Get("/", s.h.HandleSourceList())
@@ -196,10 +223,13 @@ func (s *Server) setupSourceRoutes() {
 	})
 
 	s.router.Route("/source/{sourceID}", func(r chi.Router) {
+		s.recoverPanics(
+			r, s.h.HandleErrorPage(http.StatusInternalServerError),
+		)
 		// MaxBodySize precedes CSRF and RequireAuth deliberately;
 		// see maxFormBodySize for why, and for what it costs.
 		r.Use(s.mw.MaxBodySize(maxFormBodySize))
-		r.Use(s.mw.CSRF())
+		r.Use(s.mw.CSRF(s.h.HandleErrorPage(http.StatusForbidden)))
 		r.Use(s.mw.NoCache())
 		r.Use(s.mw.RequireAuth())
 		r.Get("/", s.h.HandleSourceDetail())

templates/error.html

@@ -0,0 +1,15 @@
+{{template "base" .}}
+
+{{define "title"}}{{.StatusText}} - Webhooker{{end}}
+
+{{define "content"}}
+<div class="max-w-4xl mx-auto px-6 py-12">
+    <h1 class="text-2xl font-medium text-gray-900 mb-4">{{.Status}} {{.StatusText}}</h1>
+    <p class="text-gray-600 mb-6">{{.Message}}</p>
+    {{if .User}}
+    <a href="/sources" class="btn-secondary">Back to webhooks</a>
+    {{else}}
+    <a href="/pages/login" class="btn-primary">Sign in</a>
+    {{end}}
+</div>
+{{end}}

templates/navbar.html

@@ -24,10 +24,14 @@
                 </svg>
                 {{.User.Username}}
             </a>
+            {{/* An error page can be served before a form token is issued,
+                 and a logout without one is refused. */}}
+            {{if .CSRFToken}}
             <form method="POST" action="/pages/logout" class="inline">
                 <input type="hidden" name="csrf_token" value="{{.CSRFToken}}">
                 <button type="submit" class="btn-text">Logout</button>
             </form>
+            {{end}}
             {{else}}
             <a href="/pages/login" class="btn-primary">Login</a>
             {{end}}
@@ -40,10 +44,12 @@
             {{if .User}}
             <a href="/sources" class="btn-text w-full text-left">Webhooks</a>
             <a href="/user/{{.User.Username}}" class="btn-text w-full text-left">Profile</a>
+            {{if .CSRFToken}}
             <form method="POST" action="/pages/logout">
                 <input type="hidden" name="csrf_token" value="{{.CSRFToken}}">
                 <button type="submit" class="btn-text w-full text-left">Logout</button>
             </form>
+            {{end}}
             {{else}}
             <a href="/pages/login" class="btn-primary w-full">Login</a>
             {{end}}

templates/source_detail.html

@@ -24,8 +24,6 @@
         </div>
     </div>
 
-    {{template "webhook_stats" .}}
-
     <div class="grid grid-cols-1 lg:grid-cols-2 gap-6">
         <!-- Entrypoints -->
         <div class="card">

templates/webhook_stats.html

@@ -1,93 +0,0 @@
-{{define "webhook_stats"}}
-<!-- Statistics pane at the top of the webhook page. -->
-<div class="card mb-6">
-    <div class="p-4 border-b border-gray-200">
-        <h2 class="text-lg font-medium text-gray-900">Statistics</h2>
-    </div>
-    {{with .Stats}}
-    <div class="p-4 flex flex-wrap gap-6 text-sm border-b border-gray-200">
-        <div>
-            <span class="text-gray-500">Entrypoints</span>
-            <span class="font-medium text-gray-900">{{.Entrypoints}}</span>
-            <span class="text-gray-500">({{.ActiveEntrypoints}} active)</span>
-        </div>
-        <div>
-            <span class="text-gray-500">Targets</span>
-            <span class="font-medium text-gray-900">{{.Targets}}</span>
-            <span class="text-gray-500">({{.ActiveTargets}} active)</span>
-        </div>
-        <div>
-            <span class="text-gray-500">Deliveries in progress</span>
-            <span class="font-medium text-gray-900">{{.InProgress}}</span>
-        </div>
-        <div>
-            <span class="text-gray-500">Last event</span>
-            <span class="font-medium text-gray-900">{{with .LastEventAt}}{{.Format "2006-01-02 15:04:05 UTC"}}{{else}}none{{end}}</span>
-        </div>
-        <div>
-            <span class="text-gray-500">Retention</span>
-            <span class="font-medium text-gray-900">{{$.Webhook.RetentionLabel}}</span>
-        </div>
-    </div>
-    <div class="p-4 grid grid-cols-1 lg:grid-cols-2 gap-6 text-sm">
-        <table class="w-full text-center text-gray-900">
-            <thead>
-                <tr class="border-b border-gray-200 text-xs text-gray-500 uppercase tracking-wide">
-                    <th></th>
-                    <th class="py-2 font-medium">Lifetime</th>
-                    <th class="py-2 font-medium">Within retention</th>
-                </tr>
-            </thead>
-            <tbody>
-                <tr>
-                    <td class="py-2 text-left text-gray-600">Events</td>
-                    <td class="py-2">{{.Lifetime.Events}}</td>
-                    <td class="py-2">{{.WithinRetention.Events}}</td>
-                </tr>
-                <tr>
-                    <td class="py-2 text-left text-gray-600">Deliveries</td>
-                    <td class="py-2">{{.Lifetime.Deliveries}}</td>
-                    <td class="py-2">{{.WithinRetention.Deliveries}}</td>
-                </tr>
-                <tr>
-                    <td class="py-2 text-left text-gray-600">Failures</td>
-                    <td class="py-2">{{.Lifetime.Failures}}</td>
-                    <td class="py-2">{{.WithinRetention.Failures}}</td>
-                </tr>
-            </tbody>
-        </table>
-        <div>
-            <table class="w-full text-center text-gray-900">
-                <thead>
-                    <tr class="border-b border-gray-200 text-xs text-gray-500 uppercase tracking-wide">
-                        <th></th>
-                        <th class="py-2 font-medium">Last 10 minutes</th>
-                        <th class="py-2 font-medium">Last 24 hours</th>
-                    </tr>
-                </thead>
-                <tbody>
-                    <tr>
-                        <td class="py-2 text-left text-gray-600">Events</td>
-                        <td class="py-2">{{.Last10Minutes.Events}}</td>
-                        <td class="py-2">{{.Last24Hours.Events}}</td>
-                    </tr>
-                    <tr>
-                        <td class="py-2 text-left text-gray-600">Failures</td>
-                        <td class="py-2">{{.Last10Minutes.Failed}}</td>
-                        <td class="py-2">{{.Last24Hours.Failed}}</td>
-                    </tr>
-                    <tr>
-                        <td class="py-2 text-left text-gray-600">Failure percentage</td>
-                        <td class="py-2">{{.Last10Minutes.FailurePercent}}</td>
-                        <td class="py-2">{{.Last24Hours.FailurePercent}}</td>
-                    </tr>
-                </tbody>
-            </table>
-            <p class="mt-2 text-xs text-gray-500">Failure percentage is the failed deliveries out of all deliveries that finished in the window. Deliveries still pending or retrying are not counted.</p>
-        </div>
-    </div>
-    {{else}}
-    <div class="p-4 text-sm text-gray-500">The statistics could not be read.</div>
-    {{end}}
-</div>
-{{end}}