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Version: v1.3.3

Power Events

Power state monitoring uses D-Bus to listen for UPower events. This allows profiles and templates to react to AC/battery power changes.

Power events

Disabling Power Events​

To disable power state monitoring entirely:

hyprdynamicmonitors run --disable-power-events

When disabled:

  • The system defaults to AC power state
  • No power events will be delivered
  • No D-Bus connection will be made

Default Configuration​

By default, the service listens for D-Bus signals:

  • Signal: org.freedesktop.DBus.Properties.PropertiesChanged
  • Interface: org.freedesktop.DBus.Properties
  • Member: PropertiesChanged
  • Path: /org/freedesktop/UPower/devices/line_power_ACAD

Monitoring Power Events​

You can monitor power events with:

gdbus monitor -y -d org.freedesktop.UPower | grep -E "PropertiesChanged|Device(Added|Removed)"

Example output:

/org/freedesktop/UPower/devices/line_power_ACAD: org.freedesktop.DBus.Properties.PropertiesChanged ('org.freedesktop.UPower.Device', {'UpdateTime': <uint64 1756242314>, 'Online': <true>}, @as [])

Querying Power Status​

On each event, the current power status is queried. Equivalent command:

dbus-send --system --print-reply --dest=org.freedesktop.UPower \
  /org/freedesktop/UPower/devices/line_power_ACAD \
  org.freedesktop.DBus.Properties.Get \
  string:org.freedesktop.UPower.Device string:Online

Custom D-Bus Configuration​

You can customize which D-Bus signals to monitor and how to query power status.

Custom Signal Match Rules​

[power_events]
[[power_events.dbus_signal_match_rules]]
interface = "org.freedesktop.DBus.Properties"
member = "PropertiesChanged"
object_path = "/org/freedesktop/UPower/devices/line_power_ACAD"
# sender = "org.freedesktop.UPower"  # Optional: specific sender

You can add multiple match rules to listen for different events like DeviceAdded and DeviceRemoved.

Custom Signal Filters​

Filter received events by name to avoid noisy signals:

[[power_events.dbus_signal_receive_filters]]
name = "org.freedesktop.DBus.Properties.PropertiesChanged"

Custom UPower Query​

For non-standard power managers:

[power_events.dbus_query_object]
destination = "org.freedesktop.UPower"
path = "/org/freedesktop/UPower"
method = "org.freedesktop.DBus.Properties.Get"
expected_discharging_value = "true"

[[power_events.dbus_query_object.args]]
arg = "org.freedesktop.UPower"

[[power_events.dbus_query_object.args]]
arg = "OnBattery"

This is equivalent to:

dbus-send --system --print-reply --dest=org.freedesktop.UPower \
  /org/freedesktop/UPower \
  org.freedesktop.DBus.Properties.Get \
  string:org.freedesktop.UPower string:OnBattery
warning

The above query configuration is shown for reference only and is not recommended for production use. Stick with the default configuration unless you have a custom power management setup.

Leave Empty Token​

To explicitly remove default values from D-Bus match rules:

[[power_events.dbus_signal_match_rules]]
interface = "leaveEmptyToken"  # Removes interface match
member = "PropertiesChanged"
object_path = "/custom/path"

Session Bus vs System Bus​

By default, the service connects to the system bus. To use the session bus:

hyprdynamicmonitors run --connect-to-session-bus

This is useful if your power line events are exposed in your user session bus instead of the system bus.

Using Power State​

Power state is available in templates via functions:

{{if isOnAC}}
monitor=eDP-1,2880x1920@120,0x0,2.0
{{else}}
monitor=eDP-1,1920x1080@60,0x0,2.0
{{end}}

See Templates for more details.

Behavior​

  • Power status changes are only propagated when the state actually changes
  • Template/link replacement only occurs when file contents differ
  • This prevents unnecessary Hyprland reloads when nothing has changed