works

app/sbin/stats

@@ -1,7 +1,8 @@
 #!/usr/bin/env python3
-"""Collect server runtime stats (uptime, top, cgroup, mounts) and return as JSON."""
+"""Collect server runtime stats (uptime, top, cgroup, mounts, hdd) and return as JSON."""
 
 import json
+import os
 import subprocess
 
 
@@ -32,6 +33,20 @@ def read_file(path):
         return None
 
 
+def disk_usage(path):
+    """Total/used/available bytes for the filesystem at `path` (same figures as df)."""
+    try:
+        st = os.statvfs(path)
+        return {
+            "path": path,
+            "total_bytes": st.f_blocks * st.f_frsize,
+            "used_bytes": (st.f_blocks - st.f_bfree) * st.f_frsize,
+            "available_bytes": st.f_bavail * st.f_frsize,
+        }
+    except Exception as e:
+        return f"ERROR: {e}"
+
+
 def main():
     stats = {}
 
@@ -39,6 +54,7 @@ def main():
     stats["top"] = cmd(["sh", "-c", "top -b -n 1 | head -n 3"], splitlines=True)
     stats["cgroup"] = read_file("/proc/self/cgroup")
     stats["mounts"] = cmd(["mount"], splitlines=True)
+    stats["hdd"] = disk_usage("/")
 
     print(json.dumps(stats, indent=2))