Smarte Transkription B: Datenmodell, Einstellungen und Test-Endpunkt

TranscriptionSettings (Token Fernet-verschluesselt wie SiteLogin), TranscriptionJob und EpisodeArticle in podcasts; Source.synthetic in feeds, das Refresh, Aufraeumen, OPML-Export, Kommando und Umstellen auf Nachrichten ueberspringt bzw. verweigert. GET/POST /podcasts/transcription/settings/ und POST /podcasts/transcription/test/ (SSRF-Pruefung ueber chapters._open, jetzt auch fuer POST; eingebaute Instanz aus DIORA_WHISPER_URL ausgenommen).

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

diora/settings.py

@@ -84,6 +84,9 @@ DATABASES = {
     }
 }
 
+# The built-in Whisper instance (OpenAI-compatible, base such as http://whisper:8000/v1);
+# empty = none (docs/transcription.md).
+WHISPER_URL = os.environ.get('DIORA_WHISPER_URL', '').strip().rstrip('/')
 PODCAST_MAX_EPISODES_PER_FEED = int(os.environ.get('PODCAST_MAX_EPISODES_PER_FEED', '200'))
 
 AUTH_PASSWORD_VALIDATORS = [

docs/transcription.md

@@ -57,6 +57,9 @@ code (`de`). `parallel` is 1 to 8, default 3. `builtin_available` is whether `DI
 is set. `url` is the instance's base, e.g. `https://whisper.example.org/v1`; the server appends
 `/audio/transcriptions`.
 
+An empty `model` is sent as `whisper-1`. The built-in URL is read into `settings.WHISPER_URL` from
+`DIORA_WHISPER_URL`. A custom engine needs a `url`; the token is only sent to custom instances.
+
 `POST /podcasts/transcription/test/` sends one second of silence to the configured instance and
 returns `{ok, model, error}`. A custom URL goes through the same SSRF check as chapters
 (`podcasts/chapters.py` `_open`): no private, loopback or link-local addresses. Only the built-in
@@ -91,7 +94,7 @@ address removes the article and its item. `GET /feeds/items/<id>/` and `_item_da
 
 Synthetic sources are skipped by the feed refresh (`refresh_newsfeeds`, `refresh_now`) and by the
 pruning of old blog items (`feeds/refresh.py`). They can be hidden or have their bell turned off
-like any blog; they can't be refreshed, renamed to another URL or turned into news.
+like any blog; they can't be refreshed, renamed to another URL or turned into news. `refresh.refresh()` itself drops them, the OPML export leaves them out, and `_source_data` carries `synthetic`.
 
 **Open wishes.** `GET /podcasts/transcription/pending/` returns
 `[{episode_id, title, podcast, duration_seconds}]`: the user's episodes whose transcript is done,

feeds/management/commands/refresh_newsfeeds.py

@@ -13,7 +13,7 @@ class Command(BaseCommand):
         parser.add_argument('--source-id', type=int, help='Refresh only this source (even when backing off)')
 
     def handle(self, *args, **options):
-        qs = Source.objects.select_related('user').order_by('last_refreshed_at')
+        qs = Source.objects.filter(synthetic=False).select_related('user').order_by('last_refreshed_at')
         if options['source_id']:
             qs = qs.filter(pk=options['source_id'])
         else:

feeds/migrations/0007_transcription.py

@@ -0,0 +1,18 @@
+# Generated by Django 6.1 on 2026-11-09 08:20
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('feeds', '0006_folder_order'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='source',
+            name='synthetic',
+            field=models.BooleanField(default=False),
+        ),
+    ]

feeds/models.py

@@ -35,6 +35,9 @@ class Source(models.Model):
     fav = models.BooleanField(default=False)
     hidden = models.BooleanField(default=False)
     notify = models.BooleanField(default=False)
+    # Filled by diora itself (the blog "Podcast-Artikel"), not by a feed: never
+    # fetched, pruned, given another URL or turned into news.
+    synthetic = models.BooleanField(default=False)
 
     # Refresh bookkeeping, as for podcast feeds (see podcasts.views._fetch_feed).
     last_refreshed_at = models.DateTimeField(null=True, blank=True)

feeds/refresh.py

@@ -216,7 +216,7 @@ def expire(user, now=None):
     Item.objects.filter(user=user, gone=True, published__lt=now - timedelta(days=GONE_KEEP_DAYS)).delete()
     Story.objects.filter(user=user).exclude(items__gone=False).delete()
     # Blogs: the oldest read articles beyond BLOG_KEEP per blog.
-    for source in Source.objects.filter(user=user, kind=Source.BLOG):
+    for source in Source.objects.filter(user=user, kind=Source.BLOG, synthetic=False):
         ids = list(source.items.order_by('-published').values_list('id', flat=True)[BLOG_KEEP:])
         if ids:
             Item.objects.filter(id__in=ids, starred=False).exclude(read_at=None).delete()
@@ -225,7 +225,7 @@ def expire(user, now=None):
 def refresh(sources, deadline=None):
     """Refresh `sources` (downloads in parallel, writes one by one).
     Returns (refreshed, failed, new items)."""
-    sources = list(sources)
+    sources = [s for s in sources if not s.synthetic]   # synthetic sources have no feed to fetch
     now = timezone.now()
     keep = {}
     refreshed = failed = 0

feeds/tests.py

@@ -539,3 +539,56 @@ class NewsTextApiTest(TestCase):
         self.assertEqual(got['related'], [])
         single = self.client.get(f'/feeds/stories/{self.items[2].story_id}/overview/').json()
         self.assertNotIn('summary', single)
+
+
+class SyntheticSourceTest(TestCase):
+    """A source diora fills itself ("Podcast-Artikel") is never fetched or pruned."""
+
+    def setUp(self):
+        self.u = User.objects.create_user('tester', password='pw12345678')
+        self.client.force_login(self.u)
+        self.synth = Source.objects.create(user=self.u, url='diora://podcast-artikel', title='Podcast-Artikel',
+                                           kind='blog', fav=True, synthetic=True)
+        self.real = Source.objects.create(user=self.u, url='https://real.example/feed', title='Real', kind='blog')
+
+    def post(self, url, data):
+        return self.client.post(url, json.dumps(data), content_type='application/json')
+
+    def test_refresh_skips_it(self):
+        with mock.patch('feeds.refresh._fetch_feed', return_value=fetched(rss([]), 'https://real.example/feed')) as get:
+            refresh.refresh([self.synth, self.real])
+        self.assertEqual([c.args[0] for c in get.call_args_list], ['https://real.example/feed'])
+
+    def test_refresh_now_and_command_skip_it(self):
+        with mock.patch('feeds.refresh._fetch_feed', return_value=fetched(rss([]), 'https://real.example/feed')) as get:
+            r = self.post('/feeds/refresh/', {})
+            from django.core.management import call_command
+            call_command('refresh_newsfeeds', stdout=mock.MagicMock())
+        self.assertEqual(r.status_code, 200)
+        self.assertTrue(get.call_args_list)
+        self.assertTrue(all(c.args[0] == 'https://real.example/feed' for c in get.call_args_list))
+        call_command('refresh_newsfeeds', '--source-id', str(self.synth.id), stdout=mock.MagicMock())
+
+    def test_old_items_are_not_pruned(self):
+        old = timezone.now() - timedelta(days=400)
+        for source in (self.synth, self.real):
+            for n in range(refresh.BLOG_KEEP + 5):
+                Item.objects.create(source=source, user=self.u, kind='blog', guid_hash=f'{source.pk}-{n}',
+                                    title='x', published=old - timedelta(minutes=n), read_at=old)
+        refresh.expire(self.u)
+        self.assertEqual(self.synth.items.count(), refresh.BLOG_KEEP + 5)
+        self.assertEqual(self.real.items.count(), refresh.BLOG_KEEP)
+
+    def test_cannot_become_news_but_can_be_hidden(self):
+        r = self.post(f'/feeds/sources/{self.synth.id}/', {'kind': 'news'})
+        self.assertEqual(r.status_code, 400)
+        r = self.post(f'/feeds/sources/{self.synth.id}/', {'hidden': True, 'notify': True})
+        self.assertEqual(r.status_code, 200)
+        self.synth.refresh_from_db()
+        self.assertEqual((self.synth.kind, self.synth.hidden, self.synth.notify), ('blog', True, True))
+        self.assertTrue(r.json()['source']['synthetic'])
+
+    def test_not_in_opml(self):
+        body = self.client.get('/feeds/export.opml').content.decode()
+        self.assertIn('real.example', body)
+        self.assertNotIn('diora://', body)

feeds/views.py

@@ -93,7 +93,7 @@ def _source_data(s, unread=0, new=0, interval=None):
         'id': s.id, 'url': s.url, 'title': s.title, 'site_url': s.site_url, 'icon_url': s.icon_url,
         'kind': s.kind, 'category': s.category, 'folders': s.folders, 'fulltext': s.fulltext,
         'unread': unread, 'new': new,
-        'fav': s.fav, 'hidden': s.hidden, 'notify': s.notify,
+        'fav': s.fav, 'hidden': s.hidden, 'notify': s.notify, 'synthetic': s.synthetic,
         # Days between posts (blogs, for "Seltene zuerst"); a blog with one post counts as rare.
         'interval_days': interval,
         'last_refreshed_at': _iso(s.last_refreshed_at), 'last_error': s.last_error, 'error_count': s.error_count,
@@ -356,7 +356,7 @@ def add_sources(request):
             defaults=_place(request.user, kind, x.get('category'), x.get('folders'),
                             title=(x.get('title') or url)[:300]))
         added += created
-    sources = Source.objects.filter(user=request.user, last_refreshed_at=None)
+    sources = Source.objects.filter(user=request.user, last_refreshed_at=None, synthetic=False)
     refresh.refresh(sources, deadline=time.monotonic() + REFRESH_WAIT)
     return JsonResponse({'added': added})
 
@@ -386,6 +386,8 @@ def edit_source(request, pk):
     if body.get('fulltext') in dict(Source.FULLTEXTS):
         source.fulltext = body['fulltext']
     new_kind = _kind(body.get('kind'))
+    if source.synthetic and new_kind == Source.NEWS:
+        return JsonResponse({'error': 'Diese Quelle bleibt ein Blog'}, status=400)
     if new_kind and new_kind != source.kind:
         # A section becomes a folder and back.
         if new_kind == Source.BLOG and source.category and not source.folders:
@@ -416,7 +418,7 @@ def export_opml(request):
     if (err := _auth(request)):
         return err
     groups = {}
-    for s in Source.objects.filter(user=request.user).order_by('kind', 'category', 'title'):
+    for s in Source.objects.filter(user=request.user, synthetic=False).order_by('kind', 'category', 'title'):
         kind = 'Nachrichten' if s.kind == Source.NEWS else 'Blogs'
         place = s.category if s.kind == Source.NEWS else ((s.folders or [''])[0])
         label = kind + (f' – {place}' if place else '')
@@ -440,7 +442,7 @@ def export_opml(request):
 def refresh_now(request):
     if (err := _auth(request)):
         return err
-    refreshed, failed, new = refresh.refresh(Source.objects.filter(user=request.user),
+    refreshed, failed, new = refresh.refresh(Source.objects.filter(user=request.user, synthetic=False),
                                              deadline=time.monotonic() + REFRESH_WAIT)
     return JsonResponse({'refreshed': refreshed, 'failed': failed, 'new': new})
 
@@ -770,6 +772,8 @@ def save_login(request):
     password = body.get('password') or ''
     if source is None or not username or not password:
         return JsonResponse({'error': 'Benutzername und Passwort nötig'}, status=400)
+    if source.synthetic:
+        return JsonResponse({'error': 'Diese Quelle hat keine Adresse'}, status=400)
     try:
         adapter = logins.check_and_store(request.user, source.url, username, password)
     except logins.LoginFailed as e:

podcasts/chapters.py

@@ -128,25 +128,28 @@ FetchUnavailable = ChaptersUnavailable
 FetchInvalid = ChaptersInvalid
 
 
-def _open(url, headers):
-    """GET `url` with every redirect hop checked; the streamed response of
-    the final hop, which the caller has to close.
+def _open(url, headers, method='GET', timeout=CHAPTERS_TIMEOUT, **kwargs):
+    """`method` (GET or POST) `url` with every redirect hop checked; the streamed response of
+    the final hop, which the caller has to close. `kwargs` (data, files) go to
+    requests; a POST only follows 307/308, which keep the method and body.
 
     Raises ChaptersInvalid for permanent problems and ChaptersUnavailable for
     ones that may go away (network trouble, server errors).
     """
+    redirects = (301, 302, 303, 307, 308) if method == 'GET' else (307, 308)
     for _ in range(CHAPTERS_MAX_REDIRECTS + 1):
         try:
             assert_safe_url(url)
         except WebDAVInputError as e:
             raise ChaptersInvalid(str(e))
         try:
-            r = requests.get(url, timeout=CHAPTERS_TIMEOUT, allow_redirects=False, stream=True, headers=headers)
+            send = requests.get if method == 'GET' else requests.post
+            r = send(url, timeout=timeout, allow_redirects=False, stream=True, headers=headers, **kwargs)
         except requests.RequestException as e:
             raise ChaptersUnavailable(e.__class__.__name__)
         try:
             _assert_peer_is_safe(r)
-            if r.status_code in (301, 302, 303, 307, 308):
+            if r.status_code in redirects:
                 location = r.headers.get('Location')
                 if not location:
                     raise ChaptersInvalid('redirect without a location')
@@ -155,7 +158,7 @@ def _open(url, headers):
                 continue
             if r.status_code >= 500 or r.status_code == 429:
                 raise ChaptersUnavailable(f'HTTP {r.status_code}')
-            if r.status_code >= 400:
+            if r.status_code >= 400 or r.status_code in (301, 302, 303):
                 raise ChaptersInvalid(f'HTTP {r.status_code}')
         except WebDAVInputError as e:
             r.close()

podcasts/migrations/0027_transcription.py

@@ -0,0 +1,59 @@
+# Generated by Django 6.1 on 2026-11-09 08:20
+
+import django.db.models.deletion
+from django.conf import settings
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('feeds', '0007_transcription'),
+        ('podcasts', '0026_podcastepisode_sponsor'),
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='EpisodeArticle',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('model', models.CharField(blank=True, max_length=100)),
+                ('kind', models.CharField(blank=True, max_length=20)),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('episode', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='article', to='podcasts.podcastepisode')),
+                ('item', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='episode_article', to='feeds.item')),
+            ],
+        ),
+        migrations.CreateModel(
+            name='TranscriptionJob',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('state', models.CharField(choices=[('none', 'none'), ('queued', 'queued'), ('downloading', 'downloading'), ('transcribing', 'transcribing'), ('done', 'done'), ('error', 'error')], default='none', max_length=15)),
+                ('chunks_done', models.PositiveIntegerField(default=0)),
+                ('chunks_total', models.PositiveIntegerField(default=0)),
+                ('error', models.CharField(blank=True, max_length=500)),
+                ('want_article', models.BooleanField(default=False)),
+                ('claimed_by', models.CharField(blank=True, max_length=60)),
+                ('claimed_until', models.DateTimeField(blank=True, null=True)),
+                ('data', models.JSONField(blank=True, null=True)),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('started_at', models.DateTimeField(blank=True, null=True)),
+                ('finished_at', models.DateTimeField(blank=True, null=True)),
+                ('episode', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='transcription_job', to='podcasts.podcastepisode')),
+            ],
+        ),
+        migrations.CreateModel(
+            name='TranscriptionSettings',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('engine', models.CharField(choices=[('builtin', 'Eingebaut'), ('custom', 'Eigene Instanz')], default='builtin', max_length=10)),
+                ('url', models.CharField(blank=True, max_length=500)),
+                ('token_encrypted', models.TextField(blank=True)),
+                ('model', models.CharField(blank=True, max_length=100)),
+                ('language', models.CharField(blank=True, max_length=10)),
+                ('parallel', models.PositiveSmallIntegerField(default=3)),
+                ('user', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='transcription_settings', to=settings.AUTH_USER_MODEL)),
+            ],
+        ),
+    ]

podcasts/models.py

@@ -217,6 +217,68 @@ class EpisodeTranscript(models.Model):
         return f'Transcript of {self.episode}'
 
 
+class TranscriptionSettings(models.Model):
+    """Where a user's episodes are transcribed (docs/transcription.md): the
+    built-in Whisper instance (DIORA_WHISPER_URL) or their own."""
+    BUILTIN = 'builtin'
+    CUSTOM = 'custom'
+    ENGINES = [(BUILTIN, 'Eingebaut'), (CUSTOM, 'Eigene Instanz')]
+
+    user = models.OneToOneField(User, on_delete=models.CASCADE, related_name='transcription_settings')
+    engine = models.CharField(max_length=10, choices=ENGINES, default=BUILTIN)
+    # The instance's base, e.g. https://whisper.example.org/v1 (custom only).
+    url = models.CharField(max_length=500, blank=True)
+    # The API token, Fernet-encrypted like feeds.SiteLogin.secret; never handed out.
+    token_encrypted = models.TextField(blank=True)
+    model = models.CharField(max_length=100, blank=True)
+    # '' = automatic, else an ISO code ("de").
+    language = models.CharField(max_length=10, blank=True)
+    parallel = models.PositiveSmallIntegerField(default=3)   # 1 to 8 pieces at once
+
+    def __str__(self):
+        return f'Transcription settings of {self.user}'
+
+
+class TranscriptionJob(models.Model):
+    """One episode's transcription run, its Whisper result and the wish for an
+    article. Kept apart from EpisodeTranscript, which caches the feed's
+    transcripts and is rewritten when the feed changes them."""
+    NONE, QUEUED, DOWNLOADING, TRANSCRIBING, DONE, ERROR = (
+        'none', 'queued', 'downloading', 'transcribing', 'done', 'error')
+    STATES = [(s, s) for s in (NONE, QUEUED, DOWNLOADING, TRANSCRIBING, DONE, ERROR)]
+
+    episode = models.OneToOneField(PodcastEpisode, on_delete=models.CASCADE, related_name='transcription_job')
+    state = models.CharField(max_length=15, choices=STATES, default=NONE)
+    chunks_done = models.PositiveIntegerField(default=0)
+    chunks_total = models.PositiveIntegerField(default=0)
+    error = models.CharField(max_length=500, blank=True)
+    want_article = models.BooleanField(default=False)
+    # The device writing the article (a short name) and until when it holds the wish.
+    claimed_by = models.CharField(max_length=60, blank=True)
+    claimed_until = models.DateTimeField(null=True, blank=True)
+    # {"segments": [{start, end, speaker, text}], "source": {type: "whisper", model, language}}
+    data = models.JSONField(null=True, blank=True)
+    created_at = models.DateTimeField(auto_now_add=True)
+    started_at = models.DateTimeField(null=True, blank=True)
+    finished_at = models.DateTimeField(null=True, blank=True)
+
+    def __str__(self):
+        return f'Transcription of {self.episode} ({self.state})'
+
+
+class EpisodeArticle(models.Model):
+    """The article written from an episode's transcript; its text is the
+    feeds.Item (in the blog "Podcast-Artikel")."""
+    episode = models.OneToOneField(PodcastEpisode, on_delete=models.CASCADE, related_name='article')
+    item = models.OneToOneField('feeds.Item', on_delete=models.CASCADE, related_name='episode_article')
+    model = models.CharField(max_length=100, blank=True)
+    kind = models.CharField(max_length=20, blank=True)   # Interview, Gespräch, Monolog, Diskussion
+    created_at = models.DateTimeField(auto_now_add=True)
+
+    def __str__(self):
+        return f'Article on {self.episode}'
+
+
 # An episode counts as played this close to its end (AntennaPod's default),
 # the same rule as the apps' "als gehört zählen".
 PLAYED_BEFORE_END_SECONDS = 30

podcasts/test_transcription.py

@@ -0,0 +1,153 @@
+import io
+import json
+import wave
+from unittest.mock import MagicMock, patch
+
+from django.contrib.auth.models import User
+from django.test import TestCase, override_settings
+
+from feeds import logins
+
+from . import chapters, transcription
+from .models import TranscriptionSettings
+
+SETTINGS = '/podcasts/transcription/settings/'
+TEST = '/podcasts/transcription/test/'
+
+
+def fake_response(status=200):
+    r = MagicMock()
+    r.status_code = status
+    r.headers = {}
+    r.raw = None   # nothing to introspect for the peer check
+    return r
+
+
+class SettingsTests(TestCase):
+    def setUp(self):
+        self.user = User.objects.create_user(username='alice', password='pw12345678')
+        self.client.force_login(self.user)
+
+    def post(self, data, url=SETTINGS):
+        return self.client.post(url, json.dumps(data), content_type='application/json')
+
+    def test_requires_login(self):
+        self.client.logout()
+        self.assertEqual(self.client.get(SETTINGS).status_code, 401)
+        self.assertEqual(self.post({}, TEST).status_code, 401)
+
+    def test_defaults(self):
+        self.assertEqual(self.client.get(SETTINGS).json(), {
+            'engine': 'builtin', 'url': '', 'model': '', 'language': '', 'parallel': 3,
+            'has_token': False, 'builtin_available': False})
+        self.assertFalse(TranscriptionSettings.objects.exists())
+
+    @override_settings(WHISPER_URL='http://whisper:8000/v1')
+    def test_builtin_available_follows_the_environment_setting(self):
+        self.assertTrue(self.client.get(SETTINGS).json()['builtin_available'])
+
+    def test_roundtrip(self):
+        r = self.post({'engine': 'custom', 'url': 'https://whisper.example.org/v1/', 'model': 'large-v3',
+                       'language': 'de', 'parallel': 5, 'token': 'sk-secret'})
+        self.assertEqual(r.status_code, 200)
+        want = {'engine': 'custom', 'url': 'https://whisper.example.org/v1', 'model': 'large-v3',
+                'language': 'de', 'parallel': 5, 'has_token': True, 'builtin_available': False}
+        self.assertEqual(r.json(), want)
+        self.assertEqual(self.client.get(SETTINGS).json(), want)
+
+    def test_token_is_write_only_and_stored_encrypted(self):
+        self.post({'engine': 'custom', 'url': 'https://w.example.org/v1', 'token': 'sk-secret'})
+        conf = TranscriptionSettings.objects.get(user=self.user)
+        self.assertTrue(conf.token_encrypted)
+        self.assertNotIn('sk-secret', conf.token_encrypted)
+        self.assertEqual(transcription.token_of(conf), 'sk-secret')
+        for body in (self.client.get(SETTINGS).content, self.post({'model': 'm'}).content):
+            self.assertNotIn(b'sk-secret', body)
+            self.assertNotIn(conf.token_encrypted.encode(), body)
+        # Not sending a token keeps it; an empty one removes it.
+        conf.refresh_from_db()
+        self.assertTrue(conf.token_encrypted)
+        self.assertFalse(self.post({'token': ''}).json()['has_token'])
+        conf.refresh_from_db()
+        self.assertEqual(conf.token_encrypted, '')
+
+    def test_validation(self):
+        bad = [
+            {'engine': 'cloud'}, {'parallel': 0}, {'parallel': 9}, {'parallel': '3'}, {'parallel': True},
+            {'url': 'ftp://x.org/v1'}, {'url': 'javascript:alert(1)'}, {'url': 'whisper.local/v1'},
+            {'language': 'Deutsch'}, {'model': 5}, {'token': 5},
+            {'engine': 'custom'},   # a custom instance needs a url
+        ]
+        for body in bad:
+            self.assertEqual(self.post(body).status_code, 400, body)
+        self.assertEqual(self.client.post(SETTINGS, 'nope', content_type='application/json').status_code, 400)
+        self.assertFalse(TranscriptionSettings.objects.exists())
+        for body in ({'parallel': 1}, {'parallel': 8}, {'language': ''}, {'language': 'pt-BR'}):
+            self.assertEqual(self.post(body).status_code, 200, body)
+
+    def test_settings_are_per_user(self):
+        self.post({'parallel': 7})
+        other = User.objects.create_user(username='bob', password='pw12345678')
+        self.client.force_login(other)
+        self.assertEqual(self.client.get(SETTINGS).json()['parallel'], 3)
+
+
+class TestEndpointTests(TestCase):
+    def setUp(self):
+        self.user = User.objects.create_user(username='alice', password='pw12345678')
+        self.client.force_login(self.user)
+
+    def configure(self, **kw):
+        TranscriptionSettings.objects.update_or_create(user=self.user, defaults=kw)
+
+    def test_custom_sends_a_second_of_silence(self):
+        self.configure(engine='custom', url='https://whisper.example.org/v1', model='large-v3', language='de',
+                       token_encrypted=logins.encrypt('sk-secret'))
+        calls = []
+
+        def post(url, **kw):
+            calls.append((url, kw))
+            return fake_response()
+
+        with patch('podcasts.chapters.assert_safe_url'), patch('podcasts.chapters.requests.post', post):
+            r = self.client.post(TEST)
+        self.assertEqual(r.json(), {'ok': True, 'model': 'large-v3', 'error': ''})
+        url, kw = calls[0]
+        self.assertEqual(url, 'https://whisper.example.org/v1/audio/transcriptions')
+        self.assertEqual(kw['headers']['Authorization'], 'Bearer sk-secret')
+        self.assertEqual(kw['data']['model'], 'large-v3')
+        self.assertEqual(kw['data']['language'], 'de')
+        name, wav, mime = kw['files']['file']
+        self.assertEqual(mime, 'audio/wav')
+        with wave.open(io.BytesIO(wav)) as w:
+            self.assertEqual((w.getframerate(), w.getnchannels(), w.getnframes()), (16000, 1, 16000))
+
+    def test_custom_private_address_is_refused(self):
+        self.configure(engine='custom', url='http://127.0.0.1:9000/v1')
+        with patch('podcasts.chapters.requests.post') as post:
+            r = self.client.post(TEST)
+        self.assertFalse(r.json()['ok'])
+        self.assertTrue(r.json()['error'])
+        post.assert_not_called()
+
+    def test_custom_http_error_is_reported(self):
+        self.configure(engine='custom', url='https://whisper.example.org/v1')
+        with patch('podcasts.chapters.assert_safe_url'), \
+                patch('podcasts.chapters.requests.post', return_value=fake_response(401)):
+            r = self.client.post(TEST)
+        self.assertEqual((r.json()['ok'], r.json()['error']), (False, 'HTTP 401'))
+
+    @override_settings(WHISPER_URL='http://whisper:8000/v1')
+    def test_builtin_is_exempt_from_the_address_check(self):
+        self.configure(engine='builtin')
+        with patch('podcasts.transcription.requests.post', return_value=fake_response()) as post, \
+                patch('podcasts.chapters.assert_safe_url', side_effect=chapters.WebDAVInputError('private')):
+            r = self.client.post(TEST)
+        self.assertTrue(r.json()['ok'])
+        self.assertEqual(post.call_args.args[0], 'http://whisper:8000/v1/audio/transcriptions')
+        self.assertNotIn('Authorization', post.call_args.kwargs['headers'])
+
+    def test_builtin_without_instance(self):
+        r = self.client.post(TEST)
+        self.assertFalse(r.json()['ok'])
+        self.assertTrue(r.json()['error'])

podcasts/transcription.py

@@ -0,0 +1,152 @@
+"""Transcription settings and the test of the configured Whisper instance
+(docs/transcription.md). The job itself is podcasts/transcribe.py."""
+
+import io
+import json
+import re
+import wave
+from urllib.parse import urlsplit
+
+import requests
+from django.conf import settings
+from django.http import JsonResponse
+from django.views.decorators.csrf import csrf_exempt
+from django.views.decorators.http import require_http_methods
+
+from feeds import logins
+
+from . import chapters
+from .models import TranscriptionSettings
+
+DEFAULT_MODEL = 'whisper-1'
+TEST_TIMEOUT = 60            # a cold CPU instance may load its model first
+LANGUAGE_RE = re.compile(r'^[a-z]{2,3}(-[A-Za-z]{2,4})?$')
+
+
+def _auth(request):
+    if not request.user.is_authenticated:
+        return JsonResponse({'error': 'authentication required'}, status=401)
+    return None
+
+
+def _body(request):
+    try:
+        body = json.loads(request.body or b'{}')
+    except (ValueError, UnicodeDecodeError):
+        return None
+    return body if isinstance(body, dict) else None
+
+
+def for_user(user):
+    """The user's settings (unsaved defaults when there are none)."""
+    return TranscriptionSettings.objects.filter(user=user).first() or TranscriptionSettings(user=user)
+
+
+def token_of(conf):
+    """The plain API token ('' when there is none or it can't be read)."""
+    return (logins.decrypt(conf.token_encrypted) or '') if conf.token_encrypted else ''
+
+
+def _data(conf):
+    return {
+        'engine': conf.engine, 'url': conf.url, 'model': conf.model, 'language': conf.language,
+        'parallel': conf.parallel, 'has_token': bool(conf.token_encrypted),
+        'builtin_available': bool(settings.WHISPER_URL),
+    }
+
+
+@csrf_exempt
+@require_http_methods(['GET', 'POST'])
+def transcription_settings(request):
+    if (err := _auth(request)):
+        return err
+    conf = for_user(request.user)
+    if request.method == 'GET':
+        return JsonResponse(_data(conf))
+    body = _body(request)
+    if body is None:
+        return JsonResponse({'error': 'invalid JSON'}, status=400)
+    if 'engine' in body:
+        if body['engine'] not in dict(TranscriptionSettings.ENGINES):
+            return JsonResponse({'error': 'engine must be builtin or custom'}, status=400)
+        conf.engine = body['engine']
+    if 'url' in body:
+        url = body['url']
+        if not isinstance(url, str):
+            return JsonResponse({'error': 'url must be text'}, status=400)
+        url = url.strip().rstrip('/')
+        if url and (urlsplit(url).scheme not in ('http', 'https') or not urlsplit(url).hostname):
+            return JsonResponse({'error': 'url must start with http:// or https://'}, status=400)
+        if len(url) > 500:
+            return JsonResponse({'error': 'url too long'}, status=400)
+        conf.url = url
+    if 'model' in body:
+        if not isinstance(body['model'], str) or len(body['model'].strip()) > 100:
+            return JsonResponse({'error': 'invalid model'}, status=400)
+        conf.model = body['model'].strip()
+    if 'language' in body:
+        lang = body['language']
+        if not isinstance(lang, str) or (lang.strip() and not LANGUAGE_RE.match(lang.strip())):
+            return JsonResponse({'error': 'language must be empty or an ISO code'}, status=400)
+        conf.language = lang.strip()
+    if 'parallel' in body:
+        n = body['parallel']
+        if isinstance(n, bool) or not isinstance(n, int) or not 1 <= n <= 8:
+            return JsonResponse({'error': 'parallel must be 1 to 8'}, status=400)
+        conf.parallel = n
+    if 'token' in body:
+        if not isinstance(body['token'], str):
+            return JsonResponse({'error': 'token must be text'}, status=400)
+        conf.token_encrypted = logins.encrypt(body['token']) if body['token'] else ''
+    if conf.engine == TranscriptionSettings.CUSTOM and not conf.url:
+        return JsonResponse({'error': 'a custom instance needs a url'}, status=400)
+    conf.save()
+    return JsonResponse(_data(conf))
+
+
+def silent_wav(seconds=1, rate=16000):
+    """`seconds` of 16-bit mono silence as a WAV file, made in memory."""
+    buf = io.BytesIO()
+    with wave.open(buf, 'wb') as w:
+        w.setnchannels(1)
+        w.setsampwidth(2)
+        w.setframerate(rate)
+        w.writeframes(b'\0\0' * rate * seconds)
+    return buf.getvalue()
+
+
+@csrf_exempt
+@require_http_methods(['POST'])
+def transcription_test(request):
+    """One second of silence to the configured instance: {ok, model, error}."""
+    if (err := _auth(request)):
+        return err
+    conf = for_user(request.user)
+    builtin = conf.engine == TranscriptionSettings.BUILTIN
+    base = settings.WHISPER_URL if builtin else conf.url
+    model = conf.model or DEFAULT_MODEL
+    if not base:
+        error = 'Keine eingebaute Instanz eingerichtet' if builtin else 'Keine Adresse eingetragen'
+        return JsonResponse({'ok': False, 'model': model, 'error': error})
+    url = base.rstrip('/') + '/audio/transcriptions'
+    headers = {'User-Agent': 'diora transcription test'}
+    if not builtin and conf.token_encrypted:
+        headers['Authorization'] = 'Bearer ' + token_of(conf)
+    files = {'file': ('silence.wav', silent_wav(), 'audio/wav')}
+    data = {'model': model, 'response_format': 'json'}
+    if conf.language:
+        data['language'] = conf.language
+    try:
+        if builtin:
+            # The operator's own instance (DIORA_WHISPER_URL) may sit on a private network.
+            r = requests.post(url, headers=headers, files=files, data=data, timeout=TEST_TIMEOUT)
+            if r.status_code >= 400:
+                raise chapters.ChaptersInvalid(f'HTTP {r.status_code}')
+        else:
+            r = chapters._open(url, headers, method='POST', timeout=TEST_TIMEOUT, files=files, data=data)
+        r.close()
+    except (chapters.ChaptersInvalid, chapters.ChaptersUnavailable) as e:
+        return JsonResponse({'ok': False, 'model': model, 'error': str(e)})
+    except requests.RequestException as e:
+        return JsonResponse({'ok': False, 'model': model, 'error': e.__class__.__name__})
+    return JsonResponse({'ok': True, 'model': model, 'error': ''})

podcasts/urls.py

@@ -1,5 +1,5 @@
 from django.urls import path
-from . import audiobooks, discover, folders, radio, views
+from . import audiobooks, discover, folders, radio, transcription, views
 
 urlpatterns = [
     path('search/', views.podcast_search, name='podcast_search'),
@@ -31,6 +31,8 @@ urlpatterns = [
     path('episodes/<int:pk>/silences/', views.episode_silences, name='podcast_episode_silences'),
     path('episodes/<int:pk>/sponsor/', views.episode_sponsor, name='podcast_episode_sponsor'),
     path('episodes/<int:pk>/favorite/', views.set_favorite, name='podcast_set_favorite'),
+    path('transcription/settings/', transcription.transcription_settings, name='podcast_transcription_settings'),
+    path('transcription/test/', transcription.transcription_test, name='podcast_transcription_test'),
     path('stats/', views.podcast_stats, name='podcast_stats'),
     path('queue/', views.queue_get, name='podcast_queue_get'),
     path('queue/add/', views.queue_add, name='podcast_queue_add'),