Cache-busting for temafiler

Malene får asset('theme/style.css') som gir en relativ URL med
innholdshash (?v=…), beregnet ved bygging. Temafiler serveres nå med
max-age=1 år + immutable; URL-en endres når innholdet gjør det, så
besøkende får ny stil umiddelbart etter oppgradering.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JcEy43fNYpwg6K6oTKakWR

README.md

@@ -119,7 +119,8 @@ cp soapbox/themes/green/static/style.css data/content/themes/skog/static/   # re
 Et tema kan være **delvis**: bare filene som finnes overstyrer det innebygde `green`-temaet.
 Vil du endre malene, legg `templates/base.html`, `index.html` eller `post.html` i temamappen.
 Malene får `site`, `posts`/`post`, `html`, `source_url` og `rel(sti)` (relativ lenke fra
-gjeldende side), samt filtrene `date`, `excerpt(n)` og `tagslug`. `static/` havner under `/theme/`.
+gjeldende side), samt filtrene `date`, `excerpt(n)` og `tagslug`. Bruk `asset('theme/fil.css')` for temafiler:
+den gir en relativ URL med innholdshash (`?v=…`) for cache-busting. `static/` havner under `/theme/`.
 
 ## Lisens
 

soapbox/app.py

@@ -109,7 +109,10 @@ def _serve_public(cfg: Config, path: str):
             return redirect(request.path + "/", code=301)
         path = f"{path}index.html" if path else "index.html"
     resp = send_from_directory(root, path)
-    if path.startswith("theme/") or "." in os.path.basename(path) and not path.endswith(".html"):
+    if path.startswith("theme/"):
+        # URL-en inneholder innholdshash (?v=), så filene kan caches lenge
+        resp.headers["Cache-Control"] = "public, max-age=31536000, immutable"
+    elif "." in os.path.basename(path) and not path.endswith(".html"):
         resp.headers["Cache-Control"] = "public, max-age=3600"
     else:
         resp.headers["Cache-Control"] = "public, max-age=60"

soapbox/build.py

@@ -14,6 +14,7 @@ URL-er; den bruker ``SOAPBOX_SITE_URL``.
 
 from __future__ import annotations
 
+import hashlib
 import shutil
 from datetime import UTC, datetime
 from email.utils import format_datetime
@@ -63,9 +64,33 @@ def build_site(cfg: Config) -> int:
         shutil.rmtree(tmp)
     tmp.mkdir(parents=True)
 
+    # Statiske temafiler kopieres først, så vi kan hashe dem for cache-busting:
+    # theme/style.css?v=<hash> endrer seg bare når innholdet gjør det, og
+    # nettleseren kan dermed cache filene lenge uten å vise gammel stil etter
+    # en oppgradering. Innebygd tema først, eget tema oppå (overskriver).
+    for d in reversed(cfg.theme_dirs):
+        if (d / "static").is_dir():
+            shutil.copytree(d / "static", tmp / "theme", dirs_exist_ok=True)
+    versions = (
+        {
+            f"theme/{f.relative_to(tmp / 'theme').as_posix()}": hashlib.sha256(
+                f.read_bytes()
+            ).hexdigest()[:8]
+            for f in (tmp / "theme").rglob("*")
+            if f.is_file()
+        }
+        if (tmp / "theme").is_dir()
+        else {}
+    )
+
     def render(template: str, page_path: str, **ctx) -> str:
+        def asset(target: str) -> str:
+            url = relative_to(page_path, target)
+            return f"{url}?v={versions[target]}" if target in versions else url
+
         return env.get_template(template).render(
             site=site,
+            asset=asset,
             source_url=SOURCE_URL,
             site_url=cfg.site_url,  # absolutt; kun for Open Graph/canonical
             page_path=page_path,
@@ -138,11 +163,6 @@ def build_site(cfg: Config) -> int:
         _sitemap(cfg, posts, sorted(guests), sorted(tags), [u.username for u in users]),
     )
 
-    # Statiske filer lagvis: innebygd først, eget tema oppå (overskriver).
-    for d in reversed(cfg.theme_dirs):
-        if (d / "static").is_dir():
-            shutil.copytree(d / "static", tmp / "theme", dirs_exist_ok=True)
-
     if out.exists():
         old = out.with_name(out.name + ".old")
         if old.exists():

soapbox/themes/green/templates/base.html

@@ -5,8 +5,8 @@
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>{% block title %}{{ site.title }}{% endblock %}</title>
 {% if site.description %}<meta name="description" content="{{ site.description }}">{% endif %}
-<link rel="stylesheet" href="{{ rel('theme/style.css') }}">
-<link rel="icon" type="image/svg+xml" href="{{ rel('theme/favicon.svg') }}">
+<link rel="stylesheet" href="{{ asset('theme/style.css') }}">
+<link rel="icon" type="image/svg+xml" href="{{ asset('theme/favicon.svg') }}">
 <link rel="alternate" type="application/rss+xml" title="{{ site.title }}" href="{{ rel('feed.xml') }}">
 {# Open Graph krever absolutte URL-er; site_url er det eneste stedet det brukes utenom feed/sitemap. #}
 {% block og %}

tests/test_app.py

@@ -60,8 +60,11 @@ def test_full_flow_owner(client, cfg):
     assert r.status_code == 301 and unquote(r.headers["Location"]).endswith("/grønt-er-skjønt/")
     html = client.get("/grønt-er-skjønt/").text
     assert "<strong>verden</strong>" in html
-    assert 'href="../theme/style.css"' in html
-    assert 'href="../theme/favicon.svg"' in html
+    m = re.search(r'href="\.\./theme/style\.css\?v=([0-9a-f]{8})"', html)
+    assert m, html[:600]
+    assert re.search(r'href="\.\./theme/favicon\.svg\?v=[0-9a-f]{8}"', html)
+    r = client.get(f"/theme/style.css?v={m.group(1)}")
+    assert r.status_code == 200 and "immutable" in r.headers["Cache-Control"]
     assert 'href="../"' in html  # intern lenke omskrevet til relativ
     assert client.get("/grønt-er-skjønt/mitt-bilde.png").status_code == 200
     front = client.get("/").text
@@ -105,7 +108,7 @@ def test_guest_flow_and_isolation(client, cfg):
     assert (cfg.content_dir / "guests/gjest1/post-1/index.md").exists()
 
     html = client.get("/gjest1/post-1/").text
-    assert 'href="../../theme/style.css"' in html
+    assert re.search(r'href="\.\./\.\./theme/style\.css\?v=', html)
     assert "Gjest En" in html
     assert "Post 1" in client.get("/gjest1/").text
     assert "Post 1" in client.get("/").text  # gjesteinnlegg vises også på forsiden
@@ -146,7 +149,7 @@ def test_subpath_mount(tmp_path):
     r = client.post("/blog/admin/new", data={"csrf": csrf(client, "/blog")})
     assert r.headers["Location"].startswith("/blog/admin/edit/")
     html = client.get("/blog/").text
-    assert 'href="theme/style.css"' in html
+    assert re.search(r'href="theme/style\.css\?v=', html)
     assert re.search(r'href="admin/"', html)
     assert client.get("/blog/theme/style.css").status_code == 200
 
@@ -215,7 +218,7 @@ def test_user_theme_in_content_repo(client, cfg):
     assert 'theme = "skog"' in (cfg.content_dir / "site.toml").read_text()
     assert cfg.theme == "skog"
 
-    assert client.get("/").text.startswith("SKOG theme/style.css")
+    assert client.get("/").text.startswith("SKOG theme/style.css")  # rel() gir fortsatt ren sti
     assert client.get("/theme/style.css").text == ":root{--bg:#000}"
     assert client.get("/theme/favicon.svg").status_code == 200  # arvet fra green
     # post.html finnes ikke i skog → arves fra green
@@ -428,3 +431,15 @@ def test_user_pages(client, cfg):
         data={"csrf": token, "title": "brukere", "body": "x", "action": "publish"},
     )
     assert not (cfg.content_dir / "posts/brukere").exists()
+
+
+def test_asset_hash_changes_with_content(client, cfg):
+    login(client)
+    token = csrf(client)
+    before = re.search(r"style\.css\?v=([0-9a-f]{8})", client.get("/").text).group(1)
+    theme = cfg.content_dir / "themes" / "green2" / "static"
+    theme.mkdir(parents=True)
+    (theme / "style.css").write_text("body{color:red}")
+    client.post("/admin/settings", data={"csrf": token, "title": "T", "theme": "green2"})
+    after = re.search(r"style\.css\?v=([0-9a-f]{8})", client.get("/").text).group(1)
+    assert before != after