furtka/furtka/api.py
Daniel Maksymilian Syrnicki 5c58eade1c feat(furtka): Furtka-updates card on /settings + API endpoints
Slice 3 of the self-update story, the user-facing piece. The existing
CLI update flow now has a button next to it.

API additions (furtka/api.py):
- POST /api/furtka/update/check — thin wrapper around updater.check_update
- POST /api/furtka/update/apply — pre-checks the lockfile (409 on conflict)
  then kicks the updater off via systemd-run as a detached transient unit,
  so the update outlives the furtka-api restart it triggers. Returns 202
  with the unit name.
- GET  /api/furtka/update/status — returns the current update-state.json

UI additions (furtka/assets/www/settings/index.html):
- New "Furtka updates" card above Appearance showing installed +
  latest-available versions with Check + Update buttons.
- On apply: starts polling /update-state.json every 2s. That file is
  Caddy-served (not API-served) so the mid-update API restart doesn't
  interrupt progress reporting. Stage labels get plain-English strings
  (Downloading release… / Verifying signature… / etc.). On done: 5s
  grace, then location.reload() so the user sees the new version live.
  On rolled_back: red status with the reason string.

Tests (tests/test_api.py):
- 5 new tests covering both endpoint return shapes (success, 502 when
  updater.check_update raises, 409 when lock held, 202 on dispatch,
  status passthrough).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-04-16 13:44:34 +02:00

714 lines
26 KiB
Python

# ruff: noqa: E501 — _HTML below is a literal HTML/CSS/JS payload; wrapping
# its lines hurts readability and the rendered output is what matters here.
"""Tiny HTTP API + management UI for the Furtka resource manager.
Single stdlib http.server process, no Flask/no third-party deps so we don't
have to pip-install anything on the target. Caddy reverse-proxies /apps and
/api from :80 to here.
Security: NO AUTH. Bound to 127.0.0.1 by default; the Caddy proxy makes it
LAN-reachable. Anyone on the LAN can install/remove apps. The UI shouts this
out at the top. Auth lands when Authentik does.
"""
import json
import re
from http.server import BaseHTTPRequestHandler, HTTPServer
from furtka import dockerops, installer, reconciler
from furtka.manifest import ManifestError, load_manifest
from furtka.paths import apps_dir, bundled_apps_dir
from furtka.scanner import scan
_ICON_MAX_BYTES = 16 * 1024
_UNSAFE_SVG_PATTERNS = (
re.compile(r"<script", re.IGNORECASE),
re.compile(r"javascript:", re.IGNORECASE),
re.compile(r"\bon[a-z]+\s*=", re.IGNORECASE),
)
def _read_icon_svg(app_dir, icon_name):
"""Return an SVG string safe to inline into the /apps response, or None.
Inlined rather than served via a separate endpoint so the /apps page
renders in one round-trip (Doherty Threshold). The trust model: icons
come from bundled apps we ship in the ISO or from apps the operator
installed via the (auth-less-by-design) API — so the realistic threat
is a malformed file, not an attacker. Filter the obvious script /
event-handler vectors for defense in depth and let the browser render
the rest.
"""
if not app_dir or not icon_name:
return None
path = app_dir / icon_name
try:
if not path.is_file() or path.stat().st_size > _ICON_MAX_BYTES:
return None
data = path.read_text(encoding="utf-8")
except OSError:
return None
data = data.strip()
if data.startswith("<?xml"):
end = data.find("?>")
if end == -1:
return None
data = data[end + 2 :].lstrip()
if not data.startswith("<svg"):
return None
if any(p.search(data) for p in _UNSAFE_SVG_PATTERNS):
return None
return data
_HTML = """<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Furtka Apps</title>
<meta name="viewport" content="width=device-width,initial-scale=1">
<link rel="stylesheet" href="/style.css">
</head>
<body>
<main class="wrap">
<nav class="nav">
<a class="brand" href="/">Furtka</a>
<div class="nav-links">
<a href="/">Home</a>
<a href="/apps" aria-current="page">Apps</a>
<a href="/settings/">Settings</a>
</div>
</nav>
<h1>Furtka Apps</h1>
<p class="lede">Install or remove resource-manager apps on this Furtka box.</p>
<div class="warn">No authentication on this UI yet. Anyone on your LAN can install or remove apps. Don't expose this to the wider internet.</div>
<h2>Installed</h2>
<div id="installed"></div>
<h2>Available to install</h2>
<div id="available"></div>
<details class="log-details">
<summary>Last action</summary>
<pre id="log">(none yet)</pre>
</details>
</main>
<div id="modal-backdrop" class="modal-backdrop" role="dialog" aria-modal="true">
<div class="modal">
<h3 id="modal-title"></h3>
<div id="modal-long" class="long"></div>
<div id="modal-error" class="error"></div>
<form id="modal-form" onsubmit="return false;"></form>
<div class="modal-actions">
<button type="button" class="secondary" id="modal-cancel">Cancel</button>
<button type="button" id="modal-submit">Install</button>
</div>
</div>
</div>
<script>
function esc(s) {
const d = document.createElement('div');
d.textContent = s == null ? '' : String(s);
return d.innerHTML;
}
// Fallback when an app doesn't ship a parseable icon.svg. Simple
// stroked folder — currentColor so the tile's accent tint applies.
const FALLBACK_ICON = '<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"><path d="M3 7v12a2 2 0 0 0 2 2h14a2 2 0 0 0 2-2V9a2 2 0 0 0-2-2h-7l-2-2H5a2 2 0 0 0-2 2z"/></svg>';
function appIcon(a) {
// `a.icon_svg` is already sanitized server-side (see _read_icon_svg).
return `<div class="app-icon">${a.icon_svg || FALLBACK_ICON}</div>`;
}
const modal = {
backdrop: document.getElementById('modal-backdrop'),
title: document.getElementById('modal-title'),
long: document.getElementById('modal-long'),
form: document.getElementById('modal-form'),
error: document.getElementById('modal-error'),
submit: document.getElementById('modal-submit'),
cancel: document.getElementById('modal-cancel'),
current: null, // { name, action: 'install' | 'edit' }
};
modal.cancel.addEventListener('click', () => closeModal());
modal.backdrop.addEventListener('click', (e) => { if (e.target === modal.backdrop) closeModal(); });
document.addEventListener('keydown', (e) => { if (e.key === 'Escape') closeModal(); });
function closeModal() {
modal.backdrop.classList.remove('open');
modal.form.innerHTML = '';
modal.error.classList.remove('show');
modal.error.textContent = '';
modal.current = null;
}
async function openSettingsDialog(name, action) {
const r = await fetch(`/api/apps/${encodeURIComponent(name)}/settings`);
if (!r.ok) {
document.getElementById('log').textContent =
`[settings ${name}] HTTP ${r.status}\\n` + await r.text();
return;
}
const data = await r.json();
modal.current = { name, action };
modal.title.textContent = data.display_name || data.name;
modal.long.textContent = data.description_long || data.description || '';
modal.long.style.display = modal.long.textContent ? '' : 'none';
modal.submit.textContent = action === 'install' ? 'Install' : 'Save and restart';
if (!data.settings.length) {
// No form fields — treat as simple confirm.
modal.form.innerHTML = '<p class="hint">No settings to configure.</p>';
} else {
modal.form.innerHTML = data.settings.map(s => {
const id = `field-${esc(s.name)}`;
const value = action === 'edit' && s.type === 'password' ? '' : esc(s.value || '');
const placeholder = action === 'edit' && s.type === 'password' ? 'Leave blank to keep current' : '';
return `
<div class="field">
<label for="${id}">${esc(s.label)}${s.required ? '<span class="req">*</span>' : ''}</label>
${s.description ? `<div class="hint">${esc(s.description)}</div>` : ''}
<input
id="${id}"
name="${esc(s.name)}"
type="${s.type === 'password' ? 'password' : s.type === 'number' ? 'number' : 'text'}"
value="${value}"
placeholder="${esc(placeholder)}"
${s.required && action === 'install' ? 'required' : ''}
autocomplete="off"
spellcheck="false">
</div>`;
}).join('');
}
modal.backdrop.classList.add('open');
const first = modal.form.querySelector('input');
if (first) first.focus();
}
modal.submit.addEventListener('click', submitModal);
async function submitModal() {
if (!modal.current) return;
const { name, action } = modal.current;
const values = {};
for (const input of modal.form.querySelectorAll('input')) {
// In edit mode, skip password fields left blank — server keeps existing.
if (action === 'edit' && input.type === 'password' && input.value === '') continue;
values[input.name] = input.value;
}
modal.submit.disabled = true;
const original = modal.submit.textContent;
modal.submit.textContent = action === 'install' ? 'Installing…' : 'Saving…';
modal.error.classList.remove('show');
try {
const url = action === 'install'
? '/api/apps/install'
: `/api/apps/${encodeURIComponent(name)}/settings`;
const body = action === 'install' ? { name, settings: values } : { settings: values };
const r = await fetch(url, {
method: 'POST',
headers: {'Content-Type': 'application/json'},
body: JSON.stringify(body),
});
const data = await r.json();
document.getElementById('log').textContent =
`[${action} ${name}] HTTP ${r.status}\\n` + JSON.stringify(data, null, 2);
if (!r.ok) {
modal.error.textContent = data.error || `HTTP ${r.status}`;
modal.error.classList.add('show');
modal.submit.disabled = false;
modal.submit.textContent = original;
return;
}
closeModal();
await refresh();
} catch (e) {
modal.error.textContent = `Network error: ${e.message}`;
modal.error.classList.add('show');
modal.submit.disabled = false;
modal.submit.textContent = original;
}
}
async function refresh() {
const [installed, available] = await Promise.all([
fetch('/api/apps').then(r => r.json()),
fetch('/api/bundled').then(r => r.json()),
]);
document.getElementById('installed').innerHTML = installed.length
? installed.map(a => {
const hasSettings = a.has_settings;
return `
<div class="app">
<div class="left">
${appIcon(a)}
<div class="meta">
<span class="name">${esc(a.display_name || a.name)} <small>${esc(a.version || '')}</small></span>
<span class="desc">${esc(a.description || a.error || '')}</span>
</div>
</div>
<div class="buttons">
${hasSettings ? `<button data-op="edit" data-name="${esc(a.name)}">Settings</button>` : ''}
<button class="secondary" data-op="update" data-name="${esc(a.name)}">Update</button>
<button class="secondary" data-op="reinstall" data-name="${esc(a.name)}">Reinstall</button>
<button class="danger" data-op="remove" data-name="${esc(a.name)}">Remove</button>
</div>
</div>`;
}).join('')
: '<div class="empty">No apps installed yet.</div>';
document.getElementById('available').innerHTML = available.length
? available.map(a => `
<div class="app">
<div class="left">
${appIcon(a)}
<div class="meta">
<span class="name">${esc(a.display_name || a.name)} <small>${esc(a.version || '')}</small></span>
<span class="desc">${esc(a.description || '')}</span>
</div>
</div>
<button data-op="install" data-name="${esc(a.name)}">Install</button>
</div>`).join('')
: '<div class="empty">No bundled apps left to install.</div>';
for (const btn of document.querySelectorAll('button[data-op]')) {
btn.addEventListener('click', () => handleButton(btn.dataset.op, btn.dataset.name, btn));
}
}
async function handleButton(op, name, btn) {
if (op === 'install' || op === 'edit') {
openSettingsDialog(name, op === 'install' ? 'install' : 'edit');
return;
}
// Reinstall + update + remove are direct actions, no form.
btn.disabled = true;
const original = btn.textContent;
const labels = { reinstall: 'Reinstalling…', update: 'Checking…', remove: 'Removing…' };
btn.textContent = labels[op] || 'Working…';
try {
const urls = {
reinstall: '/api/apps/install',
remove: '/api/apps/remove',
update: `/api/apps/${encodeURIComponent(name)}/update`,
};
const r = await fetch(urls[op], {
method: 'POST',
headers: {'Content-Type': 'application/json'},
body: JSON.stringify({name}),
});
const data = await r.json();
let header = `[${op} ${name}] HTTP ${r.status}`;
if (op === 'update' && r.ok) {
header += data.updated
? ` — updated ${data.services.length} service(s)`
: ' — already up to date';
}
document.getElementById('log').textContent = header + '\\n' + JSON.stringify(data, null, 2);
} catch (e) {
document.getElementById('log').textContent = `[${op} ${name}] network error: ${e.message}`;
}
btn.textContent = original;
await refresh();
}
refresh();
</script>
</body>
</html>
"""
def _manifest_summary(m, app_dir=None):
return {
"name": m.name,
"display_name": m.display_name,
"version": m.version,
"description": m.description,
"description_long": m.description_long,
"ports": list(m.ports),
"icon": m.icon,
"icon_svg": _read_icon_svg(app_dir, m.icon),
"has_settings": bool(m.settings),
}
def _list_installed():
out = []
for r in scan(apps_dir()):
if r.ok:
d = _manifest_summary(r.manifest, r.path)
d["ok"] = True
out.append(d)
else:
out.append({"name": r.path.name, "ok": False, "error": r.error})
return out
def _list_bundled():
installed_names = {r.path.name for r in scan(apps_dir()) if r.ok}
bundled = bundled_apps_dir()
if not bundled.exists():
return []
out = []
for entry in sorted(bundled.iterdir()):
if not entry.is_dir() or entry.name in installed_names:
continue
manifest_path = entry / "manifest.json"
if not manifest_path.exists():
continue
try:
m = load_manifest(manifest_path)
except ManifestError:
continue
out.append(_manifest_summary(m, entry))
return out
def _load_manifest_for(name):
"""Return (manifest, env_values, installed_bool) for an installed or bundled app.
Returns (None, None, False) if the name doesn't resolve anywhere.
"""
target = apps_dir() / name
if target.exists() and (target / "manifest.json").exists():
try:
m = load_manifest(target / "manifest.json")
except ManifestError:
return None, None, False
values = installer.read_env_values(target / ".env")
return m, values, True
bundled = bundled_apps_dir() / name
if bundled.exists() and (bundled / "manifest.json").exists():
try:
m = load_manifest(bundled / "manifest.json")
except ManifestError:
return None, None, False
env_example = bundled / ".env.example"
values = installer.read_env_values(env_example) if env_example.exists() else {}
return m, values, False
return None, None, False
def _do_get_settings(name):
m, values, installed = _load_manifest_for(name)
if m is None:
return 404, {"error": f"{name!r} not found"}
settings_out = []
for s in m.settings:
# Never return password values back to the client — user either keeps
# the current value (blank input means "don't change") or types a new one.
if s.type == "password":
current = ""
else:
current = values.get(s.name, s.default if s.default is not None else "")
settings_out.append(
{
"name": s.name,
"label": s.label,
"description": s.description,
"type": s.type,
"required": s.required,
"default": s.default,
"value": current,
}
)
return 200, {
"name": m.name,
"display_name": m.display_name,
"description": m.description,
"description_long": m.description_long,
"installed": installed,
"settings": settings_out,
}
def _do_install(name, settings=None):
try:
src = installer.resolve_source(name)
target = installer.install_from(src, settings=settings)
except installer.InstallError as e:
return 400, {"error": str(e)}
actions = reconciler.reconcile(apps_dir())
payload = {
"installed": str(target),
"actions": [{"kind": a.kind, "target": a.target, "detail": a.detail} for a in actions],
}
# 207 Multi-Status — install copy succeeded but reconcile had per-app errors.
return (207 if reconciler.has_errors(actions) else 200, payload)
def _do_update_settings(name, settings):
"""Write settings into an installed app's .env and kick off a reinstall.
Only works for already-installed apps — use /api/apps/install for fresh
installs (since bundled-app folders under /opt/... are read-only).
"""
target = apps_dir() / name
if not target.exists():
return 404, {"error": f"{name!r} is not installed"}
try:
installer.update_env(name, settings)
except installer.InstallError as e:
return 400, {"error": str(e)}
actions = reconciler.reconcile(apps_dir())
return (
207 if reconciler.has_errors(actions) else 200,
{
"updated": name,
"actions": [{"kind": a.kind, "target": a.target, "detail": a.detail} for a in actions],
},
)
def _do_remove(name):
target = apps_dir() / name
if not target.exists():
return 404, {"error": f"{name!r} is not installed"}
compose_warning = None
try:
dockerops.compose_down(target, name)
except dockerops.DockerError as e:
compose_warning = str(e)
try:
installer.remove(name)
except installer.InstallError as e:
return 500, {"error": str(e)}
return 200, {"removed": name, "compose_warning": compose_warning}
def _do_furtka_check():
"""Thin wrapper around updater.check_update for the /api/furtka/update/check endpoint."""
from furtka import updater
try:
check = updater.check_update()
except updater.UpdateError as e:
return 502, {"error": str(e)}
return 200, {
"current": check.current,
"latest": check.latest,
"update_available": check.update_available,
}
def _do_furtka_apply():
"""Kick off a Furtka self-update detached from this process.
The API handler itself is about to be restarted (furtka-api.service is
part of what gets replaced), so we can't block the response on the
update completing. systemd-run starts the update as its own transient
unit — lifecycle independent of furtka-api, so the restart it triggers
mid-flight doesn't kill the updater.
The client polls /update-state.json (served by Caddy, not the API) to
watch progress. Returns 202 on successful dispatch; 409 if an update
is already running; 502 on systemd-run failure.
"""
import subprocess
from furtka import updater
# Check the lockfile ahead of time. systemd-run would succeed even if a
# concurrent update is running — the child process would then fail loudly
# at acquire_lock(), but the 202 would already be out. Better to 409 up
# front.
try:
fh = updater.acquire_lock()
except updater.UpdateError as e:
return 409, {"error": str(e)}
# Release the lock so the detached child can acquire it. The race between
# our release and the child's acquire is harmless — worst case the child
# logs "already in progress" and we've already 202'd.
fh.close()
try:
subprocess.run(
[
"systemd-run",
"--unit=furtka-update",
"--no-block",
"--collect",
"/usr/local/bin/furtka",
"update",
],
check=True,
capture_output=True,
text=True,
)
except FileNotFoundError:
return 502, {"error": "systemd-run not available"}
except subprocess.CalledProcessError as e:
return 502, {
"error": f"systemd-run failed: {(e.stderr or e.stdout or '').strip()}",
}
return 202, {"status": "dispatched", "unit": "furtka-update"}
def _do_furtka_status():
"""Return the latest update-state.json written by the updater.
Mirrors what Caddy serves at /update-state.json — duplicated here so the
API has a consistent endpoint surface. Returns {} if no update has ever
been attempted.
"""
from furtka import updater
return 200, updater.read_state()
def _do_update(name):
"""Pull newer container images for an installed app; restart if any changed.
Behaviour:
- 404 if the app isn't installed.
- Always runs `docker compose pull` first (cheap no-op when nothing to
fetch, touches the network).
- For each service, compares the container's running image ID against
the post-pull local image ID. If a service's image advanced, runs
`docker compose up -d` so compose recreates the affected containers
in place.
- Returns {updated: bool, services: [{service, from, to}], ...}.
"""
target = apps_dir() / name
if not target.exists():
return 404, {"error": f"{name!r} is not installed"}
try:
dockerops.compose_pull(target, name)
tags = dockerops.compose_image_tags(target, name)
changes = []
for service, tag in tags.items():
running = dockerops.running_container_image_id(target, name, service)
local = dockerops.local_image_id(tag)
if running and local and running != local:
changes.append({"service": service, "from": running, "to": local, "tag": tag})
if changes:
dockerops.compose_up(target, name)
except dockerops.DockerError as e:
return 502, {"error": str(e)}
return 200, {"app": name, "updated": bool(changes), "services": changes}
def _parse_settings_body(payload):
"""Extract and coerce the settings dict from a JSON body. Returns dict or None."""
s = payload.get("settings")
if s is None:
return None
if not isinstance(s, dict):
return False # sentinel — caller should reject
out = {}
for k, v in s.items():
if not isinstance(k, str):
return False
out[k] = "" if v is None else str(v)
return out
class _Handler(BaseHTTPRequestHandler):
def _json(self, status, payload):
body = json.dumps(payload).encode()
self.send_response(status)
self.send_header("Content-Type", "application/json")
self.send_header("Content-Length", str(len(body)))
self.end_headers()
self.wfile.write(body)
def _html(self, status, body):
b = body.encode()
self.send_response(status)
self.send_header("Content-Type", "text/html; charset=utf-8")
self.send_header("Content-Length", str(len(b)))
self.end_headers()
self.wfile.write(b)
def do_GET(self): # noqa: N802 — http.server convention
if self.path in ("/", "/apps", "/apps/"):
return self._html(200, _HTML)
if self.path == "/api/apps":
return self._json(200, _list_installed())
if self.path == "/api/bundled":
return self._json(200, _list_bundled())
if self.path == "/api/furtka/update/status":
status, body = _do_furtka_status()
return self._json(status, body)
# /api/apps/<name>/settings
if self.path.startswith("/api/apps/") and self.path.endswith("/settings"):
name = self.path[len("/api/apps/") : -len("/settings")]
if "/" in name or not name:
return self._json(400, {"error": "invalid app name"})
status, body = _do_get_settings(name)
return self._json(status, body)
self._json(404, {"error": "not found"})
def do_POST(self): # noqa: N802
length = int(self.headers.get("Content-Length", "0"))
raw = self.rfile.read(length) if length else b""
try:
payload = json.loads(raw.decode()) if raw else {}
except (UnicodeDecodeError, json.JSONDecodeError):
return self._json(400, {"error": "invalid JSON body"})
if not isinstance(payload, dict):
return self._json(400, {"error": "body must be a JSON object"})
# Per-app settings update: /api/apps/<name>/settings
if self.path.startswith("/api/apps/") and self.path.endswith("/settings"):
name = self.path[len("/api/apps/") : -len("/settings")]
if "/" in name or not name:
return self._json(400, {"error": "invalid app name"})
settings = _parse_settings_body(payload)
if settings is False or settings is None:
return self._json(400, {"error": "missing or invalid 'settings' object"})
status, body = _do_update_settings(name, settings)
return self._json(status, body)
# Per-app image update: /api/apps/<name>/update
if self.path.startswith("/api/apps/") and self.path.endswith("/update"):
name = self.path[len("/api/apps/") : -len("/update")]
if "/" in name or not name:
return self._json(400, {"error": "invalid app name"})
status, body = _do_update(name)
return self._json(status, body)
# Furtka itself: check + apply endpoints (Phase 2 self-update).
if self.path == "/api/furtka/update/check":
status, body = _do_furtka_check()
return self._json(status, body)
if self.path == "/api/furtka/update/apply":
status, body = _do_furtka_apply()
return self._json(status, body)
name = payload.get("name")
if not isinstance(name, str) or not name:
return self._json(400, {"error": "missing or empty 'name' field"})
if self.path == "/api/apps/install":
settings = _parse_settings_body(payload)
if settings is False:
return self._json(400, {"error": "'settings' must be an object"})
status, body = _do_install(name, settings=settings)
elif self.path == "/api/apps/remove":
status, body = _do_remove(name)
else:
status, body = 404, {"error": "not found"}
self._json(status, body)
def log_message(self, fmt, *args): # noqa: A003
# Quiet — systemd journal already records the access via Caddy's log.
pass
def serve(host: str = "127.0.0.1", port: int = 7000) -> None:
"""Run the API server. Blocks forever; exits on SIGINT/SIGTERM."""
server = HTTPServer((host, port), _Handler)
print(f"Furtka API listening on http://{host}:{port}/")
try:
server.serve_forever()
except KeyboardInterrupt:
pass
finally:
server.server_close()