feat: dbus stats tool

tools/dev-dbus-stats.py

@@ -0,0 +1,139 @@
+#!/bin/bash
+"true" '''\'
+set -eu
+set -o pipefail
+
+FILE="$(readlink -f "$0")"
+ROOT_DIR="$(dirname "$FILE")"
+
+if [ "$EUID" -eq 0 ]; then
+  echo "NB: Running as root, skipping tool setup check."
+else
+  "$ROOT_DIR/setup-tool-env.bash"
+fi
+
+"$ROOT_DIR/.venv/bin/python" "$FILE" "$@"
+
+exit 0 # required to stop shell execution here
+'''
+
+# Basically ripped off some other script from the internet.
+# Can't remember where, but claim no credit.
+
+import asyncio
+from dataclasses import dataclass
+from typing import Dict, List, Optional, Set
+
+from dbus_fast import BusType
+import typed_argparse as tap
+from dbus_fast.aio.message_bus import MessageBus
+from dbus_fast.signature import Variant
+
+
+def get_cmdline(pid: int):
+    if pid <= 0:
+        return "<bad PID>"
+
+    try:
+        procpath = '/proc/' + str(pid) + '/cmdline'
+        with open(procpath, 'r') as f:
+            return " ".join(f.readline().split('\0'))
+    except:
+        return "<err>"
+
+
+class Args(tap.TypedArgs):
+    show_all: bool = tap.arg(
+        help="show all connections instead of hiding those with flushed buffers"
+    )
+    system: bool = tap.arg(
+        help="connect to system bus instead of session bus", default=False
+    )
+
+
+@dataclass
+class ProcRecord:
+    wkn: List[str]
+    pid: int
+    cmd: str
+    stats: Optional[Dict[str, Variant]]
+
+
+# Parsing parameters
+async def _main(args: Args):
+    bus = MessageBus(bus_type=BusType.SYSTEM if args.system else BusType.SESSION)
+    await bus.connect()
+
+    introspect = await bus.introspect("org.freedesktop.DBus", "/org/freedesktop/DBus")
+    remote_object = bus.get_proxy_object(
+        "org.freedesktop.DBus", "/org/freedesktop/DBus", introspect
+    )
+    bus_iface = remote_object.get_interface("org.freedesktop.DBus")
+    stats_iface = remote_object.get_interface("org.freedesktop.DBus.Debug.Stats")
+
+    async def get_stats(conn: str) -> Optional[Dict[str, Variant]]:
+        try:
+            return await stats_iface.call_get_connection_stats(conn)
+        except:
+            # failed: did you enable the Stats interface? (compilation option: --enable-stats)
+            # https://bugs.freedesktop.org/show_bug.cgi?id=80759 would be nice too
+            return None
+
+    names: Set[str] = set(await bus_iface.call_list_names())
+    unique_names = {a for a in names if a.startswith(":")}
+    well_known_names = names - unique_names
+    owners = {
+        name: await bus_iface.call_get_name_owner(name) for name in well_known_names
+    }
+
+    async def fetch_info(conn: str):
+        pid: int = await bus_iface.call_get_connection_unix_process_id(conn)
+        return ProcRecord(
+            wkn=sorted(k for k, v in owners.items() if v == conn),
+            pid=pid,
+            cmd=get_cmdline(pid),
+            stats=await get_stats(conn),
+        )
+
+    def is_boring(x: ProcRecord):
+        if "klipper" in x.cmd:
+            return False
+
+        if x.stats is None:
+            return True
+
+        return (
+            x.stats['IncomingBytes'].value == 0 and x.stats['OutgoingBytes'].value == 0
+        )
+
+    stats = [(name, await fetch_info(name)) for name in unique_names]
+    stats.sort(key=lambda kv: (kv[1].pid, kv[0]))
+
+    for k, v in stats:
+        # hide boring connections
+        if not args.show_all and is_boring(v):
+            continue
+
+        print(f"{k} with pid {v.pid} '{v.cmd}':")
+        print(f"              Names: {' '.join(v.wkn)}")
+
+        if v.stats is not None:
+            print(f"      IncomingBytes: {v.stats['IncomingBytes'].value:>10}")
+            print(f"  PeakIncomingBytes: {v.stats['PeakIncomingBytes'].value:>10}")
+            print(f"      OutgoingBytes: {v.stats['OutgoingBytes'].value:>10}")
+            print(f"  PeakOutgoingBytes: {v.stats['PeakOutgoingBytes'].value:>10}")
+        else:
+            print("  No stats available.")
+
+        print("")
+
+
+def main():
+    def go(args: Args):
+        asyncio.run(_main(args))
+
+    tap.Parser(Args).bind(go).run()
+
+
+if __name__ == "__main__":
+    main()