ci: add site pipeline

tools/check_site.py

@@ -0,0 +1,59 @@
+#!/usr/bin/env python3
+import re
+import sys
+from html.parser import HTMLParser
+from pathlib import Path
+from urllib.parse import urlparse
+
+ROOT = Path(__file__).resolve().parent.parent
+INDEX = ROOT / "index.html"
+SKIP = ("#", "mailto:", "tel:", "data:", "javascript:")
+FETCH_RELS = {"stylesheet", "icon", "preload", "modulepreload", "manifest", "apple-touch-icon"}
+errors = []
+
+
+def check(ref, base, where, fetched):
+    if not ref or ref.startswith(SKIP):
+        return
+    if ref.startswith(("http://", "https://", "//")):
+        if fetched:
+            errors.append(f"{where}: external request {ref}")
+        return
+    path = urlparse(ref).path
+    target = ROOT / path.lstrip("/") if path.startswith("/") else base.parent / path
+    if not target.exists():
+        errors.append(f"{where}: missing file {ref}")
+
+
+class Page(HTMLParser):
+    def handle_starttag(self, tag, attrs):
+        a = dict(attrs)
+        refs = []
+        if tag in ("script", "img", "source", "iframe", "video", "audio"):
+            refs.append(a.get("src"))
+            for part in (a.get("srcset") or "").split(","):
+                if part.strip():
+                    refs.append(part.split()[0])
+        elif tag == "link" and FETCH_RELS & set((a.get("rel") or "").split()):
+            refs.append(a.get("href"))
+        for ref in refs:
+            check(ref, INDEX, "index.html", True)
+        if tag == "a":
+            check(a.get("href"), INDEX, "index.html", False)
+
+
+for name in ("index.html", "favicon.svg", "robots.txt"):
+    if not (ROOT / name).is_file():
+        errors.append(f"missing required file: {name}")
+
+if INDEX.is_file():
+    Page().feed(INDEX.read_text(encoding="utf-8"))
+
+for css in ROOT.glob("assets/*.css"):
+    for ref in re.findall(r"url\(\s*['\"]?([^'\")]+)", css.read_text(encoding="utf-8")):
+        check(ref, css, str(css.relative_to(ROOT)), True)
+
+if errors:
+    print("\n".join(errors))
+    sys.exit(1)
+print("site check passed")