power-profile-monitor-zbus.rs

use futures_lite::stream::StreamExt;
use zbus::names::InterfaceName;
use zbus::zvariant::Str;
use zbus::zvariant::Value;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
	const INTERFACE_NAME: InterfaceName =
		InterfaceName::from_static_str_unchecked("org.freedesktop.UPower.PowerProfiles");
	const PROPERTY_NAME: &str = "ActiveProfile";

	let connection = zbus::Connection::system().await?;

	let properties_proxy = zbus::fdo::PropertiesProxy::builder(&connection)
		.destination("org.freedesktop.UPower.PowerProfiles")?
		.path("/org/freedesktop/UPower/PowerProfiles")?
		.build()
		.await?;

	let mut changes_stream = properties_proxy
		.receive_properties_changed_with_args(&[(0, INTERFACE_NAME.as_str())])
		.await?;

	let power_profile: Str = properties_proxy
		.get(INTERFACE_NAME, PROPERTY_NAME)
		.await?
		.try_into()?;

	println!("Started with power profile {power_profile}");

	while let Some(change) = changes_stream.next().await {
		let args = change.args()?;

		if let Some(Value::Str(power_profile)) = args.changed_properties().get("ActiveProfile") {
			println!("Switched to power profile {power_profile}");
		}
	}

	Ok(())
}