Add Happy 404, featured/related sidebars, and next-post nav to the post page

Happy 404: an HTML 404 (unmatched route, or an explicit not-found inside a
real route) now renders a random existing post instead of the error page,
using the exact same context builder as a real post view. Toggle is the
happy_404_enabled site setting (default on, /admin/settings); JSON/API
requests and a handful of excluded prefixes are never affected. The pool of
candidate slugs is cached in-process and resampled periodically so it stays
fast and eventually cycles the whole posts table; on any internal failure it
falls straight through to the real 404 page.

Applying this everywhere surfaced ~60 existing tests that asserted a literal
404 for a legitimate resource-not-found flow (deleted post, unknown
container, wrong project slug, etc.) - each now disables the setting for the
duration of that specific check and restores it after, so the underlying
not-found behavior stays covered independently of the new feature.

Post page also gained, all built on the same shared post_page_context() so
they render identically on both a real post and a happy-404 page:
- A left sidebar (three separate cards, matching /feed's sidebar-card
  convention) for "Gists from {author}", "Projects from {author}" (private
  projects filtered through the normal visibility check), and "Related
  Discussions" - each cached per author and invalidated on create/edit/
  delete so new content shows up immediately.
- A right column reusing /feed's exact Daily Topic widget class for up to
  three "Featured" articles (the existing but previously-unused `featured`
  news flag), cached as a pool with per-request random sampling.
- A "Next post -> " link beside "Back to Feed", pointing at the next older
  post site-wide (blocked authors skipped). Wired through the same next_url
  mechanism already used for listing pagination, so it emits a real
  backend-rendered <link rel="next"> tag for SEO, not just a visible link.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BWJy6PrMMt5hwWxQwia2rd

tests/api/posts/create.py

@@ -4,7 +4,7 @@ import time
 from datetime import datetime, timezone
 import pytest
 import requests
-from tests.conftest import BASE_URL
+from tests.conftest import BASE_URL, CACHE_VERSION_PROPAGATION_SECONDS
 from devplacepy.database import get_table, refresh_snapshot, set_setting
 from devplacepy.utils import generate_uid, make_combined_slug
 JSON_audit_log = {"Accept": "application/json"}
@@ -29,9 +29,13 @@ def _audit_test_settings(app_server):
         "session_remember_days": "30",
         "news_service_interval": "3600",
         "news_grade_threshold": "7",
+        "happy_404_enabled": "0",
     }.items():
         set_setting(key, value)
+    time.sleep(CACHE_VERSION_PROPAGATION_SECONDS)
     yield
+    set_setting("happy_404_enabled", "1")
+    time.sleep(CACHE_VERSION_PROPAGATION_SECONDS)
 def _db_user(name):
     # the user is created by the server subprocess; refresh the test-process
     # SQLite snapshot before reading it back across the process boundary.

tests/api/posts/featured.py

@@ -0,0 +1,118 @@
+# retoor <retoor@molodetz.nl>
+
+import time
+
+import requests
+
+from devplacepy.database import get_table
+from tests.conftest import BASE_URL
+
+JSON = {"Accept": "application/json"}
+_counter = [0]
+
+
+def _unique(prefix="feat"):
+    _counter[0] += 1
+    return f"{prefix}{int(time.time() * 1000)}{_counter[0]}"
+
+
+def _signup():
+    name = _unique("featuser")
+    session = requests.Session()
+    session.post(
+        f"{BASE_URL}/auth/signup",
+        data={
+            "username": name,
+            "email": f"{name}@t.dev",
+            "password": "secret123",
+            "confirm_password": "secret123",
+            "birth_date": "1990-01-01",
+            "accept_terms": "1",
+        },
+        allow_redirects=True,
+    )
+    return session
+
+
+def _new_post(session):
+    return session.post(
+        f"{BASE_URL}/posts/create",
+        headers=JSON,
+        data={
+            "title": _unique("featpost"),
+            "content": "content for the featured topics test post",
+            "topic": "devlog",
+        },
+    ).json()["data"]
+
+
+def _seed_featured_article():
+    uid = _unique("featnews")
+    get_table("news").insert(
+        {
+            "uid": uid,
+            "title": _unique("Featured Article"),
+            "slug": _unique("featured-article"),
+            "external_id": uid,
+            "status": "published",
+            "source_name": "test",
+            "url": "https://example.com/article",
+            "description": "a featured article for the post-page test",
+            "content": "",
+            "synced_at": "2024-01-01T00:00:00",
+            "grade": 5,
+            "ai_grade": 5,
+            "show_on_landing": 0,
+            "featured": 1,
+            "featured_locked": 1,
+            "landing_locked": 0,
+            "author": "",
+            "article_published": "",
+            "image_url": "",
+            "has_unique_image": 0,
+            "deleted_at": None,
+            "deleted_by": None,
+        }
+    )
+    return uid
+
+
+def test_post_page_shows_featured_topics(app_server):
+    session = _signup()
+    post = _new_post(session)
+    _seed_featured_article()
+
+    r = requests.get(f"{BASE_URL}/posts/{post['slug']}")
+    assert r.status_code == 200
+    assert 'class="feed-right"' in r.text
+    assert "daily-topic-card" in r.text
+
+
+def test_post_page_json_includes_featured_topics(app_server):
+    session = _signup()
+    post = _new_post(session)
+    _seed_featured_article()
+
+    r = requests.get(f"{BASE_URL}/posts/{post['slug']}", headers=JSON)
+    assert r.status_code == 200
+    data = r.json()
+    assert "featured_topics" in data
+    assert len(data["featured_topics"]) <= 3
+    assert all("title" in item for item in data["featured_topics"])
+
+
+def test_post_page_featured_topics_pick_varies(app_server):
+    session = _signup()
+    post = _new_post(session)
+    for _ in range(6):
+        _seed_featured_article()
+
+    seen = set()
+    for _ in range(20):
+        r = requests.get(f"{BASE_URL}/posts/{post['slug']}", headers=JSON)
+        assert r.status_code == 200
+        titles = tuple(item["title"] for item in r.json()["featured_topics"])
+        assert len(titles) == 3
+        assert len(set(titles)) == 3
+        seen.add(titles)
+    assert len(seen) > 1, "featured topics never varied across 20 requests"

tests/api/posts/nextpost.py

@@ -0,0 +1,72 @@
+# retoor <retoor@molodetz.nl>
+
+import time
+
+import requests
+
+from tests.conftest import BASE_URL
+
+JSON = {"Accept": "application/json"}
+_counter = [0]
+
+
+def _unique(prefix="nextpost"):
+    _counter[0] += 1
+    return f"{prefix}{int(time.time() * 1000)}{_counter[0]}"
+
+
+def _signup():
+    name = _unique("nextuser")
+    session = requests.Session()
+    session.post(
+        f"{BASE_URL}/auth/signup",
+        data={
+            "username": name,
+            "email": f"{name}@t.dev",
+            "password": "secret123",
+            "confirm_password": "secret123",
+            "birth_date": "1990-01-01",
+            "accept_terms": "1",
+        },
+        allow_redirects=True,
+    )
+    return session
+
+
+def _new_post(session, title=None):
+    return session.post(
+        f"{BASE_URL}/posts/create",
+        headers=JSON,
+        data={
+            "title": title or _unique("nextpostbody"),
+            "content": "content for the next-post navigation test",
+            "topic": "devlog",
+        },
+    ).json()["data"]
+
+
+def test_newer_post_links_to_the_next_older_post(app_server):
+    session = _signup()
+    older = _new_post(session, title="Older Post For Next Nav")
+    newer = _new_post(session, title="Newer Post For Next Nav")
+
+    r = requests.get(f"{BASE_URL}/posts/{newer['slug']}", headers=JSON)
+    assert r.status_code == 200
+    assert r.json()["next_post_url"] == f"/posts/{older['slug']}"
+
+    html = requests.get(f"{BASE_URL}/posts/{newer['slug']}")
+    assert f'href="/posts/{older["slug"]}" class="back-link next-post-link"' in html.text
+    assert f'<link rel="next" href="{BASE_URL}/posts/{older["slug"]}">' in html.text
+
+
+def test_next_post_link_is_absent_when_the_url_is_none(app_server):
+    session = _signup()
+    post = _new_post(session)
+
+    data = requests.get(f"{BASE_URL}/posts/{post['slug']}", headers=JSON).json()
+    html = requests.get(f"{BASE_URL}/posts/{post['slug']}").text
+    if data["next_post_url"] is None:
+        assert "next-post-link" not in html
+        assert 'rel="next"' not in html
+    else:
+        assert f'href="{data["next_post_url"]}" class="back-link next-post-link"' in html

tests/api/posts/sidebar.py

@@ -0,0 +1,138 @@
+# retoor <retoor@molodetz.nl>
+
+import time
+
+import requests
+
+from tests.conftest import BASE_URL
+
+JSON = {"Accept": "application/json"}
+_counter = [0]
+
+
+def _unique(prefix="side"):
+    _counter[0] += 1
+    return f"{prefix}{int(time.time() * 1000)}{_counter[0]}"
+
+
+def _signup():
+    name = _unique("sideuser")
+    session = requests.Session()
+    session.post(
+        f"{BASE_URL}/auth/signup",
+        data={
+            "username": name,
+            "email": f"{name}@t.dev",
+            "password": "secret123",
+            "confirm_password": "secret123",
+            "birth_date": "1990-01-01",
+            "accept_terms": "1",
+        },
+        allow_redirects=True,
+    )
+    return session, name
+
+
+def _new_post(session):
+    return session.post(
+        f"{BASE_URL}/posts/create",
+        headers=JSON,
+        data={
+            "title": _unique("sidepost"),
+            "content": "content for the author-sidebar test post",
+            "topic": "devlog",
+        },
+    ).json()["data"]
+
+
+def _new_gist(session, title=None):
+    return session.post(
+        f"{BASE_URL}/gists/create",
+        headers=JSON,
+        data={
+            "title": title or _unique("sidegist"),
+            "description": "a gist used for the author sidebar test",
+            "source_code": "print('hi')",
+            "language": "python",
+        },
+    ).json()["data"]
+
+
+def _new_project(session, title=None, is_private=None):
+    data = {
+        "title": title or _unique("sideproj"),
+        "description": "a project used for the author sidebar test",
+        "project_type": "software",
+        "status": "In Development",
+        "platforms": "",
+    }
+    created = session.post(f"{BASE_URL}/projects/create", headers=JSON, data=data).json()["data"]
+    if is_private:
+        session.post(
+            f"{BASE_URL}/projects/{created['slug']}/private",
+            headers=JSON,
+            data={"value": "true"},
+        )
+    return created
+
+
+def test_post_page_has_no_author_cards_with_nothing_else(app_server):
+    session, name = _signup()
+    post = _new_post(session)
+    r = requests.get(f"{BASE_URL}/posts/{post['slug']}")
+    assert r.status_code == 200
+    assert f"Gists from {name}" not in r.text
+    assert f"Projects from {name}" not in r.text
+
+
+def test_post_page_shows_author_gists_and_projects(app_server):
+    session, name = _signup()
+    post = _new_post(session)
+    _new_gist(session, title="Alpha Gist")
+    _new_project(session, title="Alpha Project")
+
+    r = requests.get(f"{BASE_URL}/posts/{post['slug']}")
+    assert r.status_code == 200
+    assert f"Gists from {name}" in r.text
+    assert f"Projects from {name}" in r.text
+    assert "Alpha Gist" in r.text
+    assert "Alpha Project" in r.text
+
+
+def test_post_page_sidebar_json_parity_and_limit(app_server):
+    session, name = _signup()
+    post = _new_post(session)
+    for i in range(7):
+        _new_gist(session, title=f"Gist {i}")
+
+    r = requests.get(f"{BASE_URL}/posts/{post['slug']}", headers=JSON)
+    assert r.status_code == 200
+    data = r.json()
+    assert len(data["author_gists"]) == 5
+    assert data["author_projects"] == []
+
+
+def test_post_page_hides_private_project_from_stranger(app_server):
+    session, name = _signup()
+    post = _new_post(session)
+    _new_project(session, title="Hidden Project", is_private=True)
+
+    stranger = requests.Session()
+    r = stranger.get(f"{BASE_URL}/posts/{post['slug']}", headers=JSON)
+    assert r.status_code == 200
+    titles = [p["title"] for p in r.json()["author_projects"]]
+    assert "Hidden Project" not in titles
+
+
+def test_post_page_sidebar_updates_live_after_new_gist(app_server):
+    session, name = _signup()
+    post = _new_post(session)
+
+    r0 = requests.get(f"{BASE_URL}/posts/{post['slug']}", headers=JSON)
+    assert r0.json()["author_gists"] == []
+
+    _new_gist(session, title="Just Created Gist")
+
+    r1 = requests.get(f"{BASE_URL}/posts/{post['slug']}", headers=JSON)
+    titles = [g["title"] for g in r1.json()["author_gists"]]
+    assert "Just Created Gist" in titles