tracing_worker/
lib.rs

1pub struct WorkerLayer {
2    level: tracing::Level,
3}
4
5impl WorkerLayer {
6    pub fn new(level: tracing::Level) -> Self {
7        Self { level }
8    }
9}
10
11pub struct StringVisitor<'a> {
12    string: &'a mut String,
13}
14
15impl<'a> tracing::field::Visit for StringVisitor<'a> {
16    fn record_debug(&mut self, field: &tracing::field::Field, value: &dyn std::fmt::Debug) {
17        use std::fmt::Write;
18        if field.name() == "message" {
19            write!(self.string, "{:?}", value).ok();
20        } else {
21            write!(self.string, "{} = {:?}; ", field.name(), value).ok();
22        }
23    }
24}
25
26impl<S: tracing::Subscriber> tracing_subscriber::Layer<S> for WorkerLayer {
27    fn on_event(
28        &self,
29        event: &tracing::Event<'_>,
30        _ctx: tracing_subscriber::layer::Context<'_, S>,
31    ) {
32        if event.metadata().level() > &self.level {
33            return;
34        }
35        let date = worker::Date::now().to_string();
36        let level = event.metadata().level();
37        let target = event.metadata().target();
38        let name = event.metadata().name();
39        let mut fields = String::new();
40        let mut fields_visitor = StringVisitor {
41            string: &mut fields,
42        };
43        event.record(&mut fields_visitor);
44        worker::console_log!("{date} {level:>5} {target}: {fields} ({name})");
45    }
46}
47
48static INIT: std::sync::Once = std::sync::Once::new();
49
50pub fn init(env: &worker::Env) {
51    use tracing_subscriber::prelude::*;
52
53    INIT.call_once(|| {
54        let level = env
55            .secret("RUST_LOG")
56            .map(|s| s.to_string())
57            .unwrap_or("info".to_string())
58            .parse::<tracing::Level>()
59            .unwrap_or(tracing::Level::INFO);
60        let subscriber = tracing_subscriber::registry()
61            .with(tracing_subscriber::fmt::layer().without_time())
62            .with(WorkerLayer::new(level));
63        tracing::subscriber::set_global_default(subscriber).unwrap();
64    });
65}
tracing_worker/lib.rs

tracing_worker/
lib.rs
