Expand description
A measured, convenient approach to building traces.
[tracing-actions] is a trace recording toolbox.
It records your live spans on the heap and offers you a visitor function
which is called once per span with the ActionSpan.
Action traces, being heap-allocated, are held in an object pool to mitigate the cost of allocations. While low overhead is a goal of tracing-actions, 0-overhead is not. This is a tool for convenience first and performance second.
§Examples
§K-log
use tracing_actions;
use log;
// First, we implement k-logging.
struct KLog {
k: usize,
n: std::sync::atomic::AtomicUsize,
}
impl tracing_actions::TraceSink for KLog {
fn sink_trace(&self, action_span: &mut tracing_actions::ActionSpan) {
if self.n.fetch_add(1, std::sync::atomic::Ordering::Relaxed) % self.k == 0 {
log::info!("trace: {action_span:?}")
}
}
}
// Next, we configure a subscriber.
let level = "debug".parse().unwrap();
let k_logging_subscriber = tracing_actions::ActionTraceSubscriber::new(
level,
KLog { k: 42, n: Default::default() },
tracing_actions::span_constructor::LazySpanCache::default(),
);
// Finally, we install the subscriber.
tracing::subscriber::set_global_default(k_logging_subscriber)
.expect("I should be able to set the global trace subscriber");
// Now the rest of your application will k-log ActionSpans.