Files
turnstone/docker/healthcheck.py
Patrick Buckley 167d63b385 Add operational features: health degradation, rate limiting, workstre… (#10)
* Add operational features: health degradation, rate limiting, workstream eviction

Backend health monitor with circuit breaker (CLOSED/OPEN/HALF_OPEN) probes
LLM backend periodically; /health returns "degraded" when unreachable.
Token-bucket per-IP rate limiter with 429 + Retry-After responses;
/health and /metrics exempt. Workstream auto-eviction of oldest idle
when at configurable max_workstreams capacity.

New modules: healthcheck.py (BackendHealthMonitor, CircuitState),
ratelimit.py (TokenBucket, RateLimiter). 5 new Prometheus metrics.
Both UIs: health indicator, 429 retry with toast, eviction notifications,
node degradation badges (console), circuit state in dashboard footer.

Config: [health] and [ratelimit] TOML sections, max_workstreams in [server].
Docs: README, architecture, API reference, PlantUML diagrams updated.
616 tests pass (35 new), mypy clean, ruff clean.

* Fix Copilot PR #10 review: version import, capacity check order, validations, docs

- Use turnstone.__version__ instead of hard-coded "0.2.1" in /health and
  /metrics endpoints
- Move capacity check/eviction before session creation in
  WorkstreamManager.create() to avoid wasted work when at capacity
- Validate rate > 0 and burst >= 1 in RateLimiter when enabled
- Validate max_workstreams >= 1 in WorkstreamManager.__init__
- Parse do_POST path with urlparse for consistent rate limit exemptions
  and metrics labeling
- Fix should_allow_request docstring: HALF_OPEN allows requests through
  (not just one probe)
- Fix /health docstring: degraded when circuit is not CLOSED (includes
  HALF_OPEN)
- Add class="health-ok" to health indicator HTML to prevent visible
  empty pill before first poll
- Update PlantUML: remove stale MAX_WORKSTREAMS constant, fix
  RateLimiter.check and TokenBucket signatures; regenerate PNG
2026-03-02 22:14:03 -08:00

35 lines
911 B
Python

#!/usr/bin/env python3
"""Health check for turnstone containers.
Usage: healthcheck.py <url>
Exit 0 if the endpoint returns {"status": "ok"}, exit 1 otherwise.
Uses only stdlib — no pip dependencies required.
"""
import json
import sys
import urllib.request
def main() -> None:
if len(sys.argv) != 2:
print("Usage: healthcheck.py <url>", file=sys.stderr)
sys.exit(1)
url = sys.argv[1]
try:
req = urllib.request.Request(url, method="GET")
with urllib.request.urlopen(req, timeout=5) as resp:
data = json.loads(resp.read().decode())
if data.get("status") in ("ok", "degraded"):
sys.exit(0)
print(f"Unhealthy: {data}", file=sys.stderr)
sys.exit(1)
except Exception as exc:
print(f"Health check failed: {exc}", file=sys.stderr)
sys.exit(1)
if __name__ == "__main__":
main()