feat(infra): Phase 2 monitoring agent — rule-first + 시놀로지 Chat 알림

5분 cron용 agent. docker/disk/health/network 4개 체크.
asyncssh 로그 억제, 작은 파티션(< 1G) 무시.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

infra/agent.py

@@ -0,0 +1,194 @@
+"""Infra Monitoring Agent — rule-first, Gemma 2nd.
+
+5분마다 실행되어:
+1. core/ 함수로 상태 수집
+2. Rule 기반 1차 판정 (threshold/패턴)
+3. 이상 감지 시 → 시놀로지 Chat 알림
+4. 로그 → stdout (launchd가 캡처)
+
+Gemma 4는 Phase 2.1에서 추가 (알림 메시지 자연어 생성).
+"""
+
+from __future__ import annotations
+
+import asyncio
+import json
+import logging
+import os
+import sys
+from datetime import datetime, timezone
+from pathlib import Path
+
+import httpx
+from dotenv import load_dotenv
+
+# gpu-services 루트에서 실행되므로 infra.core를 import 가능
+from infra.core.docker import docker_status
+from infra.core.health import service_health
+from infra.core.system import disk_usage
+from infra.core.network import tailscale_status
+
+load_dotenv(Path(__file__).parent / ".env")
+
+logging.basicConfig(
+    level=logging.INFO,
+    format="%(asctime)s [%(levelname)s] %(message)s",
+    datefmt="%Y-%m-%d %H:%M:%S",
+)
+# asyncssh is extremely verbose at INFO level
+logging.getLogger("asyncssh").setLevel(logging.WARNING)
+log = logging.getLogger("infra-agent")
+
+# --- Config ---
+
+SYNOLOGY_WEBHOOK_URL = os.getenv("SYNOLOGY_INCOMING_URL", "")
+DISK_WARN_PCT = 85
+EXPECTED_TAILSCALE_HOSTS = {"sub-server", "hyungi-macmini", "hyungi-macbookpro"}
+
+# Docker containers known to be intentionally stopped
+IGNORED_CONTAINERS = {
+    "hyungi_document_server-ai-gateway-1",
+    "hyungi_document_server-ollama-1",
+}
+
+# Services to health-check
+HEALTH_SERVICES = ["document-server", "mlx", "ollama-gpu"]
+
+
+# --- Alert ---
+
+async def send_alert(message: str) -> bool:
+    """Send alert to Synology Chat via incoming webhook."""
+    if not SYNOLOGY_WEBHOOK_URL:
+        log.warning("SYNOLOGY_INCOMING_URL not set — alert skipped")
+        log.info("Alert content: %s", message)
+        return False
+
+    payload = json.dumps({"text": f"[infra-agent] {message}"}, ensure_ascii=False)
+    try:
+        async with httpx.AsyncClient(verify=False, timeout=10.0) as client:
+            resp = await client.post(
+                SYNOLOGY_WEBHOOK_URL,
+                data={"payload": payload},
+            )
+            if resp.status_code == 200:
+                log.info("Alert sent: %s", message[:100])
+                return True
+            log.error("Alert failed: %d %s", resp.status_code, resp.text)
+            return False
+    except Exception:
+        log.exception("Failed to send alert")
+        return False
+
+
+# --- Rules ---
+
+async def check_docker_rules() -> list[str]:
+    """Check Docker containers on GPU server."""
+    alerts = []
+    result = await docker_status("gpu")
+
+    if not result.ok:
+        if result.error_type:
+            alerts.append(f"GPU Docker 확인 실패: {result.error}")
+            return alerts
+
+    for c in result.containers:
+        if c.name in IGNORED_CONTAINERS:
+            continue
+        if c.status != "running":
+            alerts.append(f"GPU 컨테이너 다운: {c.name} ({c.status})")
+        elif c.status == "restarting":
+            alerts.append(f"GPU 컨테이너 재시작 중: {c.name}")
+
+    return alerts
+
+
+async def check_disk_rules() -> list[str]:
+    """Check disk usage on all hosts."""
+    alerts = []
+    for host in ["gpu", "macmini"]:
+        result = await disk_usage(host)
+        if not result.ok:
+            alerts.append(f"{host} 디스크 확인 실패: {result.error}")
+            continue
+        for fs in result.filesystems:
+            if fs.used_pct >= DISK_WARN_PCT:
+                alerts.append(
+                    f"{host} 디스크 경고: {fs.mount} {fs.used_pct}% "
+                    f"(사용 {fs.used}/{fs.total})"
+                )
+    return alerts
+
+
+async def check_health_rules() -> list[str]:
+    """Check critical services health."""
+    alerts = []
+    for svc in HEALTH_SERVICES:
+        result = await service_health(svc)
+        if not result.ok:
+            detail = result.error or result.status
+            alerts.append(f"서비스 다운: {svc} — {detail}")
+        elif result.status == "degraded":
+            alerts.append(f"서비스 저하: {svc} — {result.details}")
+    return alerts
+
+
+async def check_network_rules() -> list[str]:
+    """Check Tailscale connectivity for critical hosts."""
+    alerts = []
+    result = await tailscale_status()
+    if not result.ok:
+        alerts.append(f"Tailscale 확인 실패: {result.error}")
+        return alerts
+
+    online_hosts = {p.hostname for p in result.peers if p.status != "offline"}
+    for expected in EXPECTED_TAILSCALE_HOSTS:
+        if expected not in online_hosts:
+            alerts.append(f"Tailscale 오프라인: {expected}")
+
+    return alerts
+
+
+# --- Main ---
+
+async def run_checks() -> None:
+    """Run all checks and send alerts if needed."""
+    now = datetime.now(timezone.utc).isoformat()
+    log.info("=== 상태 수집 시작 (%s) ===", now)
+
+    all_alerts: list[str] = []
+
+    # Run all checks concurrently
+    results = await asyncio.gather(
+        check_docker_rules(),
+        check_disk_rules(),
+        check_health_rules(),
+        check_network_rules(),
+        return_exceptions=True,
+    )
+
+    for result in results:
+        if isinstance(result, Exception):
+            all_alerts.append(f"체크 실패: {result}")
+        else:
+            all_alerts.extend(result)
+
+    if all_alerts:
+        log.warning("이상 감지 %d건:", len(all_alerts))
+        for a in all_alerts:
+            log.warning("  - %s", a)
+
+        # Send combined alert
+        message = f"이상 감지 {len(all_alerts)}건:\n" + "\n".join(f"- {a}" for a in all_alerts)
+        await send_alert(message)
+    else:
+        log.info("전체 정상")
+
+
+def main():
+    asyncio.run(run_checks())
+
+
+if __name__ == "__main__":
+    main()