From 679f99659786b155b58fbe8ab6b5a92161933985 Mon Sep 17 00:00:00 2001
From: Claude <claude@webklar.local>
Date: Sun, 27 Sep 2026 16:26:27 +0000
Subject: [PATCH] Bausteine: slugify mit Umlauten, deutsche Zeit, Sperren

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 server/services/berlinTime.js | 22 ++++++++++++++++++++
 server/services/keyedLock.js  | 36 ++++++++++++++++++++++++++++++++
 server/services/slug.js       | 22 ++++++++++++++++++++
 test/berlinTime.test.js       |  7 +++++++
 test/keyedLock.test.js        | 39 +++++++++++++++++++++++++++++++++++
 test/slug.test.js             | 18 ++++++++++++++++
 6 files changed, 144 insertions(+)
 create mode 100644 server/services/berlinTime.js
 create mode 100644 server/services/keyedLock.js
 create mode 100644 server/services/slug.js
 create mode 100644 test/berlinTime.test.js
 create mode 100644 test/keyedLock.test.js
 create mode 100644 test/slug.test.js

diff --git a/server/services/berlinTime.js b/server/services/berlinTime.js
new file mode 100644
index 0000000..1d6dc0f
--- /dev/null
+++ b/server/services/berlinTime.js
@@ -0,0 +1,22 @@
+/**
+ * Datum und Uhrzeit in der Berliner Zeitzone (beruecksichtigt MESZ/MEZ automatisch),
+ * fuer Anzeige und Dateinamen. date: 'tt.mm.jjjj', time: 'hhmm' (24h, '0030' statt '2430').
+ */
+export function berlinDateTime(date = new Date()) {
+  const parts = new Intl.DateTimeFormat('de-DE', {
+    timeZone: 'Europe/Berlin',
+    day: '2-digit',
+    month: '2-digit',
+    year: 'numeric',
+    hour: '2-digit',
+    minute: '2-digit',
+    hourCycle: 'h23',
+  }).formatToParts(date)
+
+  const value = (type) => parts.find((part) => part.type === type)?.value
+
+  return {
+    date: `${value('day')}.${value('month')}.${value('year')}`,
+    time: `${value('hour')}${value('minute')}`,
+  }
+}
diff --git a/server/services/keyedLock.js b/server/services/keyedLock.js
new file mode 100644
index 0000000..d350bf1
--- /dev/null
+++ b/server/services/keyedLock.js
@@ -0,0 +1,36 @@
+/**
+ * Sperren je Schluessel (z. B. Kundennummer, Ticket-Id), damit parallele Anfragen fuer
+ * dieselbe Ressource nacheinander laufen, waehrend Anfragen zu anderen Schluesseln parallel
+ * bleiben. Ein Aufruf kann mehrere Schluessel auf einmal sperren (alle muessen frei werden).
+ * waitMs begrenzt, wie lange auf die aktuellen Inhaber gewartet wird (Default: unbegrenzt);
+ * nach Ablauf laeuft fn trotzdem los, ohne weiter zu warten.
+ *
+ * Umsetzung: je Schluessel eine Promise-Kette (das "tail") in einer modulweiten Map.
+ */
+const tailsByKey = new Map()
+
+// setTimeout(fn, Infinity) wuerde Node zu 1 ms clampen (samt Warnung) - hier bewusst
+// eine Promise, die nie aufloest, damit "unbegrenzt warten" auch wirklich unbegrenzt ist.
+const sleep = (ms) =>
+  ms === Infinity ? new Promise(() => {}) : new Promise((resolve) => setTimeout(resolve, ms))
+
+export async function withLocks(keys, fn, { waitMs = Infinity } = {}) {
+  const previousTails = keys.map((key) => tailsByKey.get(key)).filter(Boolean)
+
+  let releaseTail
+  const tail = new Promise((resolve) => {
+    releaseTail = resolve
+  })
+  for (const key of keys) tailsByKey.set(key, tail)
+
+  await Promise.race([Promise.allSettled(previousTails), sleep(waitMs)])
+
+  try {
+    return await fn()
+  } finally {
+    releaseTail()
+    for (const key of keys) {
+      if (tailsByKey.get(key) === tail) tailsByKey.delete(key)
+    }
+  }
+}
diff --git a/server/services/slug.js b/server/services/slug.js
new file mode 100644
index 0000000..f93ace0
--- /dev/null
+++ b/server/services/slug.js
@@ -0,0 +1,22 @@
+/**
+ * URL-/Dateiname-taugliches Kuerzel aus beliebigem Text: klein geschrieben, deutsche
+ * Umlaute ausgeschrieben (ä→ae, ö→oe, ü→ue, ß→ss), Akzente entfernt, Apostrophe entfernt,
+ * alles ausser a-z/0-9/- wird zu einem einzelnen '-', Rand-Bindestriche entfernt, auf
+ * 100 Zeichen gekuerzt. Kein Text (z. B. null/undefined) ergibt ''.
+ */
+export function slugify(value) {
+  const input = value === null || value === undefined ? '' : String(value)
+
+  return input
+    .toLowerCase()
+    .replace(/ä/g, 'ae')
+    .replace(/ö/g, 'oe')
+    .replace(/ü/g, 'ue')
+    .replace(/ß/g, 'ss')
+    .normalize('NFD')
+    .replace(/\p{M}/gu, '')
+    .replace(/['’‘`]/g, '')
+    .replace(/[^a-z0-9-]+/g, '-')
+    .replace(/^-+|-+$/g, '')
+    .slice(0, 100)
+}
diff --git a/test/berlinTime.test.js b/test/berlinTime.test.js
new file mode 100644
index 0000000..3866d18
--- /dev/null
+++ b/test/berlinTime.test.js
@@ -0,0 +1,7 @@
+import { test } from 'node:test'
+import assert from 'node:assert/strict'
+import { berlinDateTime } from '../server/services/berlinTime.js'
+
+test('Sommerzeit', () => assert.deepEqual(berlinDateTime(new Date('2026-09-27T14:46:34Z')), { date: '27.09.2026', time: '1646' }))
+test('Winterzeit', () => assert.deepEqual(berlinDateTime(new Date('2026-01-15T10:05:00Z')), { date: '15.01.2026', time: '1105' }))
+test('nach Mitternacht UTC', () => assert.deepEqual(berlinDateTime(new Date('2026-09-27T22:30:00Z')), { date: '28.09.2026', time: '0030' }))
diff --git a/test/keyedLock.test.js b/test/keyedLock.test.js
new file mode 100644
index 0000000..d232006
--- /dev/null
+++ b/test/keyedLock.test.js
@@ -0,0 +1,39 @@
+import { test, beforeEach } from 'node:test'
+import assert from 'node:assert/strict'
+import { withLocks } from '../server/services/keyedLock.js'
+
+const sleep = (ms) => new Promise((r) => setTimeout(r, ms))
+
+let log
+beforeEach(() => {
+  log = []
+})
+
+const job = (name, ms) => async () => {
+  log.push(name + ':start')
+  await sleep(ms)
+  log.push(name + ':end')
+}
+
+test('gleicher Schlüssel läuft nacheinander', async () => {
+  await Promise.all([withLocks(['a'], job('1', 50)), withLocks(['a'], job('2', 10))])
+  assert.deepEqual(log, ['1:start', '1:end', '2:start', '2:end'])
+})
+test('verschiedene Schlüssel laufen parallel', async () => {
+  await Promise.all([withLocks(['a'], job('1', 50)), withLocks(['b'], job('2', 10))])
+  assert.deepEqual(log.slice(0, 2), ['1:start', '2:start'])
+})
+test('mehrere Schlüssel sperren alle', async () => {
+  await Promise.all([withLocks(['a', 'b'], job('1', 50)), withLocks(['b'], job('2', 10))])
+  assert.deepEqual(log, ['1:start', '1:end', '2:start', '2:end'])
+})
+test('waitMs begrenzt das Warten', async () => {
+  const t0 = Date.now()
+  let started
+  await Promise.all([withLocks(['a'], job('1', 300)), withLocks(['a'], async () => { started = Date.now() - t0 }, { waitMs: 50 })])
+  assert.ok(started >= 45 && started < 250, `gestartet nach ${started} ms`)
+})
+test('Fehler geben die Sperre frei', async () => {
+  await assert.rejects(withLocks(['a'], async () => { throw new Error('x') }))
+  assert.equal(await withLocks(['a'], async () => 42), 42)
+})
diff --git a/test/slug.test.js b/test/slug.test.js
new file mode 100644
index 0000000..ff03986
--- /dev/null
+++ b/test/slug.test.js
@@ -0,0 +1,18 @@
+import { test } from 'node:test'
+import assert from 'node:assert/strict'
+import { slugify } from '../server/services/slug.js'
+
+test('Umlaute', () => {
+  assert.equal(slugify('Döner Nation'), 'doener-nation')
+  assert.equal(slugify('Größe Überall Ärger'), 'groesse-ueberall-aerger')
+})
+test('Apostrophe entfallen', () => {
+  assert.equal(slugify("Emma's Schatzkiste"), 'emmas-schatzkiste')
+  assert.equal(slugify('Emma’s'), 'emmas')
+})
+test('Akzente', () => assert.equal(slugify('Café Élan'), 'cafe-elan'))
+test('Sonderzeichen, Ränder, Länge', () => {
+  assert.equal(slugify('--A&B--'), 'a-b')
+  assert.equal(slugify('x'.repeat(150)).length, 100)
+  assert.equal(slugify(null), '')
+})