feat(snapshot): post-json-builder mit fallback-summary

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

snapshot/src/core/post-json.ts

@@ -0,0 +1,108 @@
+import { nip19 } from 'nostr-tools'
+import type { SignedEvent } from './types.ts'
+
+export interface CoverImage {
+  url: string
+  width?: number
+  height?: number
+  alt?: string
+  mime?: string
+}
+
+export interface TranslationRef {
+  lang: string
+  slug: string
+  title: string
+}
+
+export interface PostJson {
+  slug: string
+  event_id: string
+  created_at: number
+  published_at: number
+  title: string
+  summary: string
+  lang: string
+  cover_image: CoverImage | null
+  content_markdown: string
+  tags: string[]
+  naddr: string
+  habla_url: string
+  translations: TranslationRef[]
+}
+
+const SUMMARY_MAX = 200
+
+function tagValue(ev: SignedEvent, name: string): string | undefined {
+  return ev.tags.find((t) => t[0] === name)?.[1]
+}
+
+function tagsAll(ev: SignedEvent, name: string): string[] {
+  return ev.tags.filter((t) => t[0] === name).map((t) => t[1])
+}
+
+function deriveSummary(content: string): string {
+  const flat = content.replace(/\s+/g, ' ').trim()
+  if (flat.length <= SUMMARY_MAX) return flat
+  const cut = flat.slice(0, SUMMARY_MAX)
+  const lastSpace = cut.lastIndexOf(' ')
+  const trimmed = lastSpace > SUMMARY_MAX * 0.5 ? cut.slice(0, lastSpace) : cut
+  return trimmed + '…'
+}
+
+export function buildPostJson(
+  ev: SignedEvent,
+  titleByDtag: Map<string, string>,
+): PostJson {
+  const slug = tagValue(ev, 'd') ?? ''
+  const title = tagValue(ev, 'title') ?? ''
+  const summaryTag = tagValue(ev, 'summary')
+  const summary = summaryTag && summaryTag.length > 0 ? summaryTag : deriveSummary(ev.content)
+  const image = tagValue(ev, 'image')
+  const publishedAtRaw = tagValue(ev, 'published_at')
+  const publishedAt = publishedAtRaw ? parseInt(publishedAtRaw, 10) : ev.created_at
+  const lang = ev.tags.find((t) => t[0] === 'l' && t[2] === 'ISO-639-1')?.[1] ?? 'de'
+
+  const cover_image: CoverImage | null = image
+    ? { url: image, alt: title || undefined }
+    : null
+
+  const naddr = nip19.naddrEncode({
+    kind: ev.kind,
+    pubkey: ev.pubkey,
+    identifier: slug,
+  })
+
+  const translations: TranslationRef[] = []
+  for (const tag of ev.tags) {
+    if (tag[0] !== 'a') continue
+    if (tag[3] !== 'translation') continue
+    const coord = tag[1]
+    if (!coord) continue
+    const parts = coord.split(':')
+    if (parts.length !== 3) continue
+    const otherSlug = parts[2]
+    const otherTitle = titleByDtag.get(otherSlug) ?? otherSlug
+    translations.push({
+      lang: lang === 'de' ? 'en' : 'de',
+      slug: otherSlug,
+      title: otherTitle,
+    })
+  }
+
+  return {
+    slug,
+    event_id: ev.id,
+    created_at: ev.created_at,
+    published_at: publishedAt,
+    title,
+    summary,
+    lang,
+    cover_image,
+    content_markdown: ev.content,
+    tags: tagsAll(ev, 't'),
+    naddr,
+    habla_url: `https://habla.news/a/${naddr}`,
+    translations,
+  }
+}

snapshot/tests/post-json.test.ts

@@ -0,0 +1,83 @@
+import { assertEquals } from '@std/assert'
+import { buildPostJson } from '../src/core/post-json.ts'
+import type { SignedEvent } from '../src/core/types.ts'
+
+const PUBKEY = '4fa5d1c413e2b45e10d40bf3562ab701a5331206e359c90baae0e99bfd6c6e41'
+
+function buildEvent(opts: {
+  d: string
+  title: string
+  summary?: string
+  image?: string
+  publishedAt?: number
+  lang?: string
+  tags?: string[]
+  translationCoords?: string[]
+  content: string
+}): SignedEvent {
+  const tags: string[][] = [['d', opts.d], ['title', opts.title]]
+  if (opts.summary) tags.push(['summary', opts.summary])
+  if (opts.image) tags.push(['image', opts.image])
+  if (opts.publishedAt) tags.push(['published_at', String(opts.publishedAt)])
+  if (opts.lang) {
+    tags.push(['L', 'ISO-639-1'])
+    tags.push(['l', opts.lang, 'ISO-639-1'])
+  }
+  for (const t of opts.tags ?? []) tags.push(['t', t])
+  for (const c of opts.translationCoords ?? []) tags.push(['a', c, '', 'translation'])
+  return {
+    id: 'event-' + opts.d, pubkey: PUBKEY, created_at: 1700000000, kind: 30023,
+    sig: 'sig', content: opts.content, tags,
+  }
+}
+
+Deno.test('buildPostJson: vollstaendiges event', () => {
+  const ev = buildEvent({
+    d: 'bibel-selfies', title: 'Bibel-Selfies', summary: 'Kurz',
+    image: 'https://blossom.edufeed.org/abc.jpg',
+    publishedAt: 1699000000, lang: 'de', tags: ['Bibel'],
+    translationCoords: [`30023:${PUBKEY}:bible-selfies`],
+    content: '# body',
+  })
+  const titleByDtag = new Map([['bible-selfies', 'Bible-Selfies']])
+  const json = buildPostJson(ev, titleByDtag)
+  assertEquals(json.slug, 'bibel-selfies')
+  assertEquals(json.title, 'Bibel-Selfies')
+  assertEquals(json.summary, 'Kurz')
+  assertEquals(json.lang, 'de')
+  assertEquals(json.tags, ['Bibel'])
+  assertEquals(json.published_at, 1699000000)
+  assertEquals(json.cover_image?.url, 'https://blossom.edufeed.org/abc.jpg')
+  assertEquals(json.translations, [
+    { lang: 'en', slug: 'bible-selfies', title: 'Bible-Selfies' },
+  ])
+  assertEquals(json.content_markdown, '# body')
+})
+
+Deno.test('buildPostJson: fallback summary aus content', () => {
+  const ev = buildEvent({
+    d: 'no-summary', title: 'X', content: 'Lorem ipsum dolor sit amet.'.repeat(20),
+  })
+  const json = buildPostJson(ev, new Map())
+  if (!json.summary) throw new Error('summary fehlt')
+  if (json.summary.length > 220) throw new Error('summary zu lang')
+  if (!json.summary.endsWith('…')) throw new Error('summary ohne ellipsis')
+})
+
+Deno.test('buildPostJson: fehlt published_at -> created_at', () => {
+  const ev = buildEvent({ d: 'no-pub', title: 'X', content: 'x' })
+  const json = buildPostJson(ev, new Map())
+  assertEquals(json.published_at, 1700000000)
+})
+
+Deno.test('buildPostJson: fehlt image -> cover_image null', () => {
+  const ev = buildEvent({ d: 'no-img', title: 'X', content: 'x' })
+  const json = buildPostJson(ev, new Map())
+  assertEquals(json.cover_image, null)
+})
+
+Deno.test('buildPostJson: lang default de wenn keine l-tags', () => {
+  const ev = buildEvent({ d: 'no-lang', title: 'X', content: 'x' })
+  const json = buildPostJson(ev, new Map())
+  assertEquals(json.lang, 'de')
+})