initial POC

2026-08-11 17:18:15 +02:00
parent 9822c62cec
commit 8af31c94b5
9 changed files with 368 additions and 1 deletions
@@ -0,0 +1,81 @@
+#!/usr/bin/env python3
+"""Generate system-monitor PNG graphs from its RRD database."""
+
+from __future__ import annotations
+
+import argparse
+import configparser
+import html
+from pathlib import Path
+import subprocess
+
+
+PERIODS = {"3hours": "3h", "1day": "1d", "2weeks": "2w", "1year": "1y"}
+COLORS = ["#2563EB", "#DC2626", "#16A34A", "#9333EA"]
+
+
+def graph(output: Path, rrd: Path, start: str, title: str, unit: str,
+          series: list[tuple[str, str, str]], logarithmic: bool = False) -> None:
+    args = ["rrdtool", "graph", str(output), "--start", f"end-{start}",
+            "--end", "now", "--width", "900", "--height", "260",
+            "--title", title, "--vertical-label", unit, "--slope-mode",
+            "--watermark", "cheap-system-monitor"]
+    if logarithmic:
+        args += ["--logarithmic", "--lower-limit", "1"]
+    for index, (ds, label, cf) in enumerate(series):
+        var = f"v{index}"
+        args += [f"DEF:{var}={rrd}:{ds}:{cf}",
+                 f"LINE{2 if index < 3 else 1}:{var}{COLORS[index % len(COLORS)]}:{label}",
+                 f"GPRINT:{var}:LAST:Current\\:%8.2lf%s",
+                 f"GPRINT:{var}:AVERAGE:Average\\:%8.2lf%s",
+                 f"GPRINT:{var}:MAX:Maximum\\:%8.2lf%s\\n"]
+    subprocess.run(args, check=True)
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--config", default="/etc/cheap-system-monitor.conf")
+    args = parser.parse_args()
+    config_parser = configparser.ConfigParser()
+    if not config_parser.read(args.config):
+        raise SystemExit(f"Configuration file not found: {args.config}")
+    config = config_parser["monitor"]
+    rrd = Path(config["rrd_file"])
+    if not rrd.exists():
+        raise SystemExit(f"RRD file does not exist: {rrd}")
+    output_dir = Path(config.get("graph_dir", "/var/www/html/system-monitor"))
+    output_dir.mkdir(parents=True, exist_ok=True)
+    mounts = [item.strip() for item in config["mountpoints"].split(",") if item.strip()]
+    if not mounts or mounts[0] != "/":
+        mounts.insert(0, "/")
+    definitions = [
+        ("load", "Processor load", "load", [("load1", "1 minute", "AVERAGE"), ("load5", "5 minutes", "AVERAGE"), ("load15", "15 minutes", "AVERAGE")], False),
+        ("cpu", "CPU usage", "%", [("cpu_user", "user", "AVERAGE"), ("cpu_system", "system", "AVERAGE"), ("cpu_nice", "nice", "AVERAGE")], False),
+        ("network", "Network throughput", "bytes/s", [("net_in", "received", "AVERAGE"), ("net_out", "sent", "AVERAGE")], False),
+        ("disk", "Disk usage", "%", [(f"disk_{'root' if i == 0 else i}", mount, "AVERAGE") for i, mount in enumerate(mounts)], False),
+        ("memory", "Memory usage", "%", [("memory", "used", "AVERAGE")], False),
+    ]
+    for period_name, start in PERIODS.items():
+        for filename, title, unit, series, logarithmic in definitions:
+            graph(output_dir / f"{filename}-{period_name}.png", rrd, start,
+                  f"{title} — {period_name}", unit, series, logarithmic)
+    cards = "\n".join(
+        f'<section><h2>{html.escape(title)}</h2>' + "".join(
+            f'<figure><figcaption>{period}</figcaption>'
+            f'<img src="{filename}-{period}.png" alt="{html.escape(title)}, {period}"></figure>'
+            for period in PERIODS
+        ) + "</section>"
+        for filename, title, _unit, _series, _logarithmic in definitions
+    )
+    page = f"""<!doctype html>
+<html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width">
+<meta http-equiv="refresh" content="300"><title>System monitor</title>
+<style>body{{font:16px system-ui;margin:auto;max-width:1100px;padding:1rem;background:#f8fafc;color:#172033}}
+section{{background:white;padding:1rem;margin:1rem 0;border-radius:.5rem;box-shadow:0 1px 4px #0002}}
+figure{{margin:1rem 0}} img{{width:100%;height:auto}} figcaption{{font-weight:600}}</style>
+</head><body><h1>System monitor</h1>{cards}</body></html>"""
+    (output_dir / "index.html").write_text(page)
+
+
+if __name__ == "__main__":
+    main()