Simple script to detect monitor changes

40-sway-hotplug.rules

ACTION=="change", SUBSYSTEM=="drm", RUN+="/usr/bin/machinectl --uid=<YOUR-USER-NAME> shell .host /bin/bash -c '/bin/systemctl start --no-block --user sway-monitor'"

sway-monitor-update.py

#!/usr/bin/env python

import subprocess
import json
import time

EXTERNAL_MONITOR_NAMES = set(['DELL U2718Q', 'DELL U3011'])
outputs_str = subprocess.check_output('swaymsg -s $SWAYSOCK -r -t get_outputs', shell=True)
outputs = json.loads(outputs_str)

output_names = set(x["model"] for x in outputs)

if len(EXTERNAL_MONITOR_NAMES.intersection(output_names)) > 0:
    print("Dock detected")
    subprocess.check_output('swaymsg -s $SWAYSOCK output eDP-1 disable', shell=True)
else :
    print("Roaming detected")
    subprocess.check_output('swaymsg -s $SWAYSOCK output eDP-1 enable', shell=True)

sway-monitor.service

[Unit]
Description=sway-monitor execution hook
After=sleep.target
StartLimitInterval=5
StartLimitBurst=1

[Service]
ExecStart=/usr/local/bin/sway-monitor-update.py
Type=oneshot
RemainAfterExit=false
KillMode=process

[Install]
WantedBy=sleep.target