Takes the first two commits from #15375 and adds suggestions from this comment: https://github.com/bevyengine/bevy/pull/15375#issuecomment-2366968300 See #15375 for more reasoning/motivation. ## Rebasing (rerunning) ```rust git switch simpler-lint-fixes git reset --hard main cargo fmt --all -- --unstable-features --config normalize_comments=true,imports_granularity=Crate cargo fmt --all git add --update git commit --message "rustfmt" cargo clippy --workspace --all-targets --all-features --fix cargo fmt --all -- --unstable-features --config normalize_comments=true,imports_granularity=Crate cargo fmt --all git add --update git commit --message "clippy" git cherry-pick e6c0b94f6795222310fb812fa5c4512661fc7887 ```
		
			
				
	
	
		
			56 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			56 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
//! This example illustrates how to add custom log layers in bevy.
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use bevy::{
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    log::{tracing_subscriber::Layer, BoxedLayer},
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    prelude::*,
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    utils::tracing::Subscriber,
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};
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struct CustomLayer;
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impl<S: Subscriber> Layer<S> for CustomLayer {
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    fn on_event(
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        &self,
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        event: &bevy::utils::tracing::Event<'_>,
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        _ctx: bevy::log::tracing_subscriber::layer::Context<'_, S>,
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    ) {
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        println!("Got event!");
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        println!("  level={:?}", event.metadata().level());
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        println!("  target={:?}", event.metadata().target());
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        println!("  name={:?}", event.metadata().name());
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    }
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}
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// We don't need App for this example, as we are just printing log information.
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// For an example that uses App, see log_layers_ecs.
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fn custom_layer(_app: &mut App) -> Option<BoxedLayer> {
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    // You can provide multiple layers like this, since Vec<Layer> is also a layer:
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    Some(Box::new(vec![
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        bevy::log::tracing_subscriber::fmt::layer()
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            .with_file(true)
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            .boxed(),
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        CustomLayer.boxed(),
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    ]))
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}
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fn main() {
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    App::new()
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        .add_plugins(DefaultPlugins.set(bevy::log::LogPlugin {
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            custom_layer,
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            ..default()
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        }))
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        .add_systems(Update, log_system)
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        .run();
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}
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fn log_system() {
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    // here is how you write new logs at each "log level" (in "most important" to
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    // "least important" order)
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    error!("something failed");
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    warn!("something bad happened that isn't a failure, but thats worth calling out");
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    info!("helpful information that is worth printing by default");
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    debug!("helpful for debugging");
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    trace!("very noisy");
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}
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