automatic backup disk on/off

roles/backup_server/files/backup-disk-onoff.py

@@ -1,5 +1,24 @@
+#!/usr/bin/env python3
 import subprocess
 import json
+import sys
+import paho.mqtt.client as mqtt
+import time
+
+def send_mqtt_message(topic, payload):
+    client = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2)  # Use the latest API version
+    client.connect("mqtt.chaos", 1883, 60)
+    client.publish(topic, payload)
+    client.disconnect()
+
+def get_args(name='default', first='on'):
+    return first
+
+mode = get_args(*sys.argv)
+print(f"Mode is: {mode}")
+if mode not in ["on", "off"]:
+    print("Error: mode must be either 'on' or 'off'")
+    sys.exit(1)
 
 # Run the systemctl command and capture the output
 try:
@@ -21,7 +40,7 @@ except json.JSONDecodeError as e:
     print(f"Error parsing JSON: {e}")
     exit(1)
 
-# Filter units that are loaded, active, and sub: running
+# Filter units that are loaded, active, and sub: running, and start with 'backup-'
 running_units = []
 for unit in units:
     if (
@@ -36,3 +55,46 @@ for unit in units:
 print("Units with load: loaded, active: active, sub: running:")
 for unit in running_units:
     print(f"  - {unit['unit']}: {unit['description']}")
+
+# Send MQTT message based on mode
+if mode == "on" or (mode == "off" and running_units):
+    # Send ON MQTT message
+    print(f"Turning backup Disk ON")
+    send_mqtt_message("switch_backup/switch/switch_backup_power/command", "on")
+    time.sleep(15)
+    # ON case: Send ON message after waiting 5 seconds and running vgchange -ay backup if needed
+    if mode == "on":
+        # Check if 'backup' VG is active
+        try:
+            result = subprocess.run(
+                ["vgdisplay", "-cA"],
+                stdout=subprocess.PIPE,
+                stderr=subprocess.PIPE,
+                text=True,
+                check=True
+            )
+            vgdisplay_output = result.stdout.strip().split("\n")
+            print(f"vgdisplay: {vgdisplay_output}")
+            backup_present = any(line.split(":")[0].strip() == "backup" for line in vgdisplay_output)
+            print(f"backup VG active? {backup_present}")
+            if not backup_present:
+                try:
+                    print(f"Activating VG backup")
+                    subprocess.run(["vgchange", "-ay", "backup"], check=True)
+                except subprocess.CalledProcessError as e:
+                    print(f"Error executing vgchange: {e.stderr}")
+                    exit(1)
+        except subprocess.CalledProcessError as e:
+            print(f"Error executing vgdisplay: {e.stderr}")
+            exit(1)
+else:
+    # OFF case: Only execute if nothing is mounted
+    if not running_units:
+        print(f"Turning backup Disk OFF")
+        subprocess.run(["sync"], check=True)
+        try:
+            subprocess.run(["vgchange", "-an", "backup"], check=True)
+        except subprocess.CalledProcessError as e:
+            print(f"Error executing vgchange: {e.stderr}")
+            exit(1)
+        send_mqtt_message("switch_backup/switch/switch_backup_power/command", "off")