Homepage (TDD slice 7): fix the /admin/ path + status.json perms

Two real bugs found on the first production deploy:
- /admin/ 404'd: file_server looked for /srv/homepage/admin/ (a dir), but the
  page is admin.html. Add '@admin rewrite * /admin.html' so the /admin/ path
  serves admin.html.
- The pages used relative refs (style.css, app.js, services.json, status.json),
  which from /admin/ resolved to /admin/... (404). Add <base href="/"> so all
  refs resolve to the site root on both pages.
- status.json was written 0600 (root); the checker now chmods it 0644 so Caddy
  can serve it regardless of its user.

dankclaw/Caddyfile

@@ -54,6 +54,7 @@ dankclaw.franksdank.cloud {
 	basicauth @admin {
 		frank REPLACE_WITH_ADMIN_HASH
 	}
+	@admin rewrite * /admin.html
 	root * /srv/homepage
 	file_server
 }

scripts/homepage-status.py

@@ -71,6 +71,7 @@ def main(argv):
         with os.fdopen(fd, "w") as f:
             json.dump(doc, f)
         os.replace(tmp, out_path)
+        os.chmod(out_path, 0o644)  # world-readable so Caddy can serve it
     except Exception:
         if os.path.exists(tmp):
             os.unlink(tmp)

shared/homepage/admin.html

@@ -4,6 +4,7 @@
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>frank — admin</title>
+<base href="/">
 <link rel="stylesheet" href="style.css">
 </head>
 <body>

shared/homepage/index.html

@@ -4,6 +4,7 @@
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>frank — services</title>
+<base href="/">
 <link rel="stylesheet" href="style.css">
 </head>
 <body>

tests/homepage_caddy.bats

@@ -24,3 +24,7 @@ setup() {
     grep -q "root \* /srv/homepage" "$CADDY"
     grep -q "file_server" "$CADDY"
 }
+
+@test "the /admin/ path is rewritten to admin.html" {
+    grep -qE "@admin[[:space:]]+rewrite[[:space:]]+\*[[:space:]]+/admin.html" "$CADDY"
+}

tests/homepage_checker.bats

@@ -88,3 +88,10 @@ assert s["realhttp"] == "up", s
 PY
     kill "$RAW_PID" "$HTTP_PID" 2>/dev/null
 }
+
+@test "the checker writes status.json world-readable so Caddy can serve it" {
+    local svc="$TMP/services.json" out="$TMP/status.json"
+    echo '[{"name":"x","category":"user","probe":"127.0.0.1:1","method":"tcp","wip":true}]' > "$svc"
+    python3 "$CHECKER" "$svc" "$out"
+    [ "$(stat -c %a "$out")" = "644" ]
+}

tests/homepage_pages.bats

@@ -43,3 +43,8 @@ setup() {
     grep -q "deployed-at" "$BASE/admin.html"
     grep -q "deployed-at" "$BASE/app.js"
 }
+
+@test "the pages set a base so the /admin/ page resolves refs to the root" {
+    grep -q '<base href="/">' "$BASE/index.html"
+    grep -q '<base href="/">' "$BASE/admin.html"
+}