Messen statt vermuten: 18 Abfragen auf 8, Ladebudget, Blaettern ueberall

Arbeitspaket M sagte "Abfragen je Seite zaehlen. Messen, dann zusammenfassen."
Messen braucht ein Messgeraet, also gibt es jetzt eines: ein Zaehler als
Doctrine-Middleware, dessen Zahl ausserhalb der Produktion im Kopf
X-Kant-Queries steht. Keine Profiler-Maschinerie, eine Zahl.

Die erste Messung: die Startseite brauchte 18 Abfragen. Nicht wegen einer
komplizierten Seite, sondern weil SiteSettings::load() und Theme::load() je
Aufrufer dieselbe Zeile erneut holten - Renderer, strukturierte Daten,
Einwilligungsschalter, Vorlagen. Beide merken sich ihren Stand jetzt fuer die
Dauer einer Anfrage: 18 auf 8.

Dabei ist mir die klassische Falle des Merkens selbst passiert, und ein
bestehender Test hat sie sofort gezeigt: ich leerte den Merker am Anfang des
Speicherns. Das Speichern liest den Stand aber noch einmal und fuellte ihn
damit erneut - der Rest der Anfrage bekam den alten Stand. Geleert wird jetzt
nach dem Schreiben.

Das Ladebudget wird gemessen statt behauptet: die Browserpruefung liest je
Seite HTML-Groesse, CSS-Groesse, Anzahl Anfragen, Anzahl Skripte und
Abfragezahl und prueft Obergrenzen. Startseite: 7,4 KB HTML, 22,7 KB CSS, 2
Anfragen, 8 Abfragen, 0 Skripte. Die Null ist die wichtigste Zahl - sie haelt
als Test fest, was bisher nur Absicht war.

Das erste Bild einer Seite ist nicht mehr lazy. Es ist meistens das groesste
Ding ueber der Falz, und es zu verzoegern verzoegert genau das Pixel, auf das
jemand wartet. Der Renderer bestimmt es in Renderreihenfolge, Kopfbereich
zuerst.

Eine feste Obergrenze ist kein Blaettern: der Fassungsverlauf hoerte bei
dreissig auf, die Einsendungen bei fuenfzig, die Weiterleitungen zeigten bis
zu zweitausend auf einmal. Das Erste sieht aus wie "es gibt dreissig" und ist
das Einzige, was eine Historie nicht tun darf. Alle drei blaettern jetzt, mit
derselben Rechnung und demselben Pager wie Beitragsarchiv und Mediathek.

347 PHP-Tests / 1422 Assertions unter PHP 8.2.12 und 8.4.22.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/Content/FormRepository.php

@@ -253,10 +253,15 @@ final class FormRepository
         $this->db->executeStatement('UPDATE form_submission SET delivered = ? WHERE id = ?', [true, $submissionId]);
     }
 
-    /** @return list<array{id: string, form: string, data: array, createdAt: string, consentAt: ?string, delivered: bool}> */
-    public function submissions(int $limit = 100): array
+    /**
+     * One page of the submissions, newest first.
+     *
+     * @return array{items: list<array>, page: int, pages: int, total: int}
+     */
+    public function submissions(int $number = 1, int $perPage = 25): array
     {
-        return array_map(static fn (array $row): array => [
+        $slice = Pagination::of($number, (int) $this->db->fetchOne('SELECT COUNT(*) FROM form_submission'), $perPage);
+        $items = array_map(static fn (array $row): array => [
             'id' => $row['id'],
             'form' => $row['name'] ?? $row['form_id'],
             'data' => json_decode($row['data'], true, 512, JSON_THROW_ON_ERROR),
@@ -264,7 +269,9 @@ final class FormRepository
             'consentAt' => $row['consent_at'],
             'delivered' => (bool) $row['delivered'],
         ], $this->db->fetchAllAssociative(
-            'SELECT s.*, f.name FROM form_submission s LEFT JOIN form f ON f.id = s.form_id ORDER BY s.created_at DESC, s.id DESC LIMIT '.max(1, min($limit, 500)),
+            'SELECT s.*, f.name FROM form_submission s LEFT JOIN form f ON f.id = s.form_id ORDER BY s.created_at DESC, s.id DESC LIMIT '.$slice['perPage'].' OFFSET '.$slice['offset'],
         ));
+
+        return ['items' => $items, 'page' => $slice['page'], 'pages' => $slice['pages'], 'total' => $slice['total']];
     }
 }

src/Content/PageRepository.php

@@ -208,11 +208,20 @@ final class PageRepository
     }
 
     /** @return list<array{id: string, createdAt: string, title: string, published: bool, draft: bool}> */
-    public function revisions(string $pageId, int $limit = 30): array
+    /**
+     * One page of the history, newest first.
+     *
+     * It used to stop at thirty without saying so - which looks like "there are thirty" and is
+     * the one thing a history must not do.
+     *
+     * @return array{items: list<array>, page: int, pages: int, total: int}
+     */
+    public function revisions(string $pageId, int $number = 1, int $perPage = 25): array
     {
+        $slice = Pagination::of($number, (int) $this->db->fetchOne('SELECT COUNT(*) FROM revision WHERE page_id = ?', [$pageId]), $perPage);
         $page = $this->db->fetchAssociative('SELECT published_revision_id, draft_revision_id FROM page WHERE id = ?', [$pageId]);
 
-        return array_map(static function (array $row) use ($page): array {
+        $items = array_map(static function (array $row) use ($page): array {
             $document = json_decode($row['document'], true, 512, JSON_THROW_ON_ERROR);
 
             return [
@@ -223,9 +232,11 @@ final class PageRepository
                 'draft' => $row['id'] === ($page['draft_revision_id'] ?? null),
             ];
         }, $this->db->fetchAllAssociative(
-            'SELECT id, created_at, document FROM revision WHERE page_id = ? ORDER BY seq DESC LIMIT '.max(1, min($limit, 100)),
+            'SELECT id, created_at, document FROM revision WHERE page_id = ? ORDER BY seq DESC LIMIT '.$slice['perPage'].' OFFSET '.$slice['offset'],
             [$pageId],
         ));
+
+        return ['items' => $items, 'page' => $slice['page'], 'pages' => $slice['pages'], 'total' => $slice['total']];
     }
 
     /**

src/Content/Pagination.php

@@ -0,0 +1,32 @@
+<?php
+
+namespace App\Content;
+
+/**
+ * The arithmetic every paged list needs, in one place.
+ *
+ * A fixed upper limit is not pagination: it shows the first thirty entries and says nothing about
+ * the rest. This makes "there are more, here is how to reach them" cheap enough that no list has
+ * to settle for a cap.
+ */
+final class Pagination
+{
+    /**
+     * @return array{page: int, pages: int, offset: int, perPage: int, total: int}
+     */
+    public static function of(int $page, int $total, int $perPage): array
+    {
+        $perPage = max(1, min(200, $perPage));
+        $pages = max(1, (int) ceil($total / $perPage));
+        // A page beyond the end shows the last one rather than an empty screen.
+        $page = max(1, min($page, $pages));
+
+        return [
+            'page' => $page,
+            'pages' => $pages,
+            'offset' => ($page - 1) * $perPage,
+            'perPage' => $perPage,
+            'total' => $total,
+        ];
+    }
+}

src/Content/RedirectRepository.php

@@ -17,12 +17,23 @@ final class RedirectRepository
     {
     }
 
-    /** @return list<array{id: string, from: string, to: ?string, status: int}> */
-    public function all(): array
+    /**
+     * One page of the redirects. There can be up to MAX of them, and a list of two thousand rows
+     * is not a list anybody reads.
+     *
+     * @return array{items: list<array{id: string, from: string, to: ?string, status: int}>, page: int, pages: int, total: int}
+     */
+    public function all(int $number = 1, int $perPage = 50): array
     {
-        return array_map(static fn (array $row): array => [
+        $slice = Pagination::of($number, (int) $this->db->fetchOne('SELECT COUNT(*) FROM redirect WHERE website_id = ?', ['default']), $perPage);
+        $items = array_map(static fn (array $row): array => [
             'id' => $row['id'], 'from' => $row['from_path'], 'to' => $row['to_path'], 'status' => (int) $row['status'],
-        ], $this->db->fetchAllAssociative('SELECT * FROM redirect WHERE website_id = ? ORDER BY from_path', ['default']));
+        ], $this->db->fetchAllAssociative(
+            'SELECT * FROM redirect WHERE website_id = ? ORDER BY from_path LIMIT '.$slice['perPage'].' OFFSET '.$slice['offset'],
+            ['default'],
+        ));
+
+        return ['items' => $items, 'page' => $slice['page'], 'pages' => $slice['pages'], 'total' => $slice['total']];
     }
 
     /** @return array{to: ?string, status: int}|null */

src/Content/SiteSettings.php

@@ -40,12 +40,24 @@ final class SiteSettings
     {
     }
 
+    /**
+     * Remembered for the length of one request.
+     *
+     * These settings are asked for several times per page - by the renderer, by the structured
+     * data, by the consent gate, by the templates - and each time it was the same row again. The
+     * value is dropped on every save, so nothing stale survives a change.
+     */
+    private ?array $loaded = null;
+
     public function load(): array
     {
+        if (null !== $this->loaded) {
+            return $this->loaded;
+        }
         $raw = $this->db->fetchOne('SELECT settings FROM website WHERE id = ?', ['default']);
         $stored = is_string($raw) ? json_decode($raw, true, 512, JSON_THROW_ON_ERROR) : [];
 
-        return [...self::DEFAULTS, ...(is_array($stored) ? $stored : [])];
+        return $this->loaded = [...self::DEFAULTS, ...(is_array($stored) ? $stored : [])];
     }
 
     public function save(array $input): void
@@ -132,6 +144,7 @@ final class SiteSettings
             }
         }
 
+        $this->loaded = null;
         $this->db->executeStatement('UPDATE website SET settings = ? WHERE id = ?', [
             json_encode($values, JSON_THROW_ON_ERROR | JSON_UNESCAPED_UNICODE),
             'default',

src/Content/Theme.php

@@ -56,15 +56,21 @@ final class Theme
     {
     }
 
+    /** Remembered for one request, like the settings; dropped on every write. */
+    private ?array $loaded = null;
+
     public function load(): array
     {
+        if (null !== $this->loaded) {
+            return $this->loaded;
+        }
         $raw = $this->db->fetchOne('SELECT theme FROM website WHERE id = ?', ['default']);
         $stored = is_string($raw) ? json_decode($raw, true, 512, JSON_THROW_ON_ERROR) : [];
         if (!is_array($stored) || !isset($stored['colors'], $stored['fonts'], $stored['base'])) {
-            return [...self::DEFAULTS, 'presets' => []];
+            return $this->loaded = [...self::DEFAULTS, 'presets' => []];
         }
 
-        return [
+        return $this->loaded = [
             'colors' => $stored['colors'],
             'fonts' => $stored['fonts'],
             'base' => [...self::DEFAULTS['base'], ...$stored['base']],
@@ -97,6 +103,9 @@ final class Theme
             json_encode($theme, JSON_THROW_ON_ERROR | JSON_UNESCAPED_UNICODE),
             'default',
         ]);
+        // After the write, never before: saving reads the theme again, and an early reset
+        // would only refill the memo with the state that is about to be replaced.
+        $this->loaded = null;
     }
 
     private function colors(array $input): array
@@ -240,6 +249,9 @@ final class Theme
             json_encode([...$theme, 'presets' => $presets], JSON_THROW_ON_ERROR | JSON_UNESCAPED_UNICODE),
             'default',
         ]);
+        // After the write, never before: saving reads the theme again, and an early reset
+        // would only refill the memo with the state that is about to be replaced.
+        $this->loaded = null;
     }
 
     /** The stylesheet every page carries: palette variables, font variables and base typography. */