Proven working Postgresql monitor

2026-09-17 09:23:17 -04:00
commit 0123da0e12
7 changed files with 769 additions and 0 deletions
@@ -0,0 +1,165 @@
+#!/usr/bin/env python3
+
+import json
+import os
+import signal
+import socket
+import traceback
+
+from registry import Registry, RegistryError
+
+
+SOCKET_PATH = os.environ.get(
+    "MANAGED_CONTAINERD_SOCKET",
+    "/run/managed-containerd/managed-containerd.sock",
+)
+
+server_socket = None
+registry = None
+
+
+def handle_request(req):
+    action = req.get("action")
+
+    if action == "ping":
+        return {
+            "ok": True,
+            "daemon": "managed-containerd",
+            "protocol_version": 1,
+        }
+
+    if action == "registry.list":
+        return {
+            "ok": True,
+            "resources": registry.list_resources(),
+        }
+
+    resource = req.get("resource")
+
+    if not resource:
+        return {
+            "ok": False,
+            "error": "resource is required",
+        }
+
+    return registry.execute(
+        resource,
+        action,
+    )
+
+
+def cleanup_socket():
+    try:
+        os.unlink(SOCKET_PATH)
+    except FileNotFoundError:
+        pass
+
+
+def shutdown(signum, frame):
+    global server_socket
+
+    print(
+        f"managed-containerd received signal {signum}; shutting down",
+        flush=True,
+    )
+
+    if server_socket is not None:
+        try:
+            server_socket.close()
+        except OSError:
+            pass
+
+    cleanup_socket()
+    raise SystemExit(0)
+
+
+def serve():
+    global server_socket
+    global registry
+
+    registry = Registry()
+
+    os.makedirs(
+        os.path.dirname(SOCKET_PATH),
+        exist_ok=True,
+    )
+
+    cleanup_socket()
+
+    signal.signal(signal.SIGTERM, shutdown)
+    signal.signal(signal.SIGINT, shutdown)
+
+    server_socket = socket.socket(
+        socket.AF_UNIX,
+        socket.SOCK_STREAM,
+    )
+
+    server_socket.bind(SOCKET_PATH)
+    os.chmod(SOCKET_PATH, 0o660)
+    server_socket.listen(16)
+
+    print(
+        f"managed-containerd listening on {SOCKET_PATH}",
+        flush=True,
+    )
+
+    print(
+        "registered resources: "
+        + ", ".join(registry.resources),
+        flush=True,
+    )
+
+    try:
+        while True:
+            conn, _ = server_socket.accept()
+
+            with conn:
+                try:
+                    raw = b""
+
+                    while b"\n" not in raw:
+                        chunk = conn.recv(65536)
+
+                        if not chunk:
+                            break
+
+                        raw += chunk
+
+                    req = json.loads(
+                        raw.decode("utf-8").strip()
+                    )
+
+                    response = handle_request(req)
+
+                except (
+                    RegistryError,
+                    ValueError,
+                    KeyError,
+                ) as exc:
+                    response = {
+                        "ok": False,
+                        "error": str(exc),
+                    }
+
+                except Exception as exc:
+                    traceback.print_exc()
+
+                    response = {
+                        "ok": False,
+                        "error": str(exc),
+                    }
+
+                conn.sendall(
+                    json.dumps(
+                        response,
+                        default=str,
+                    ).encode("utf-8")
+                    + b"\n"
+                )
+
+    finally:
+        cleanup_socket()
+
+
+if __name__ == "__main__":
+    serve()