spacetimedb/util/
prometheus_handle.rs

1use std::time::Instant;
2
3use prometheus::{Histogram, IntGauge};
4
5/// Decrements the inner [`IntGauge`] on drop.
6pub struct GaugeInc {
7    gauge: IntGauge,
8}
9impl Drop for GaugeInc {
10    #[inline]
11    fn drop(&mut self) {
12        self.gauge.dec();
13    }
14}
15
16/// Increment the given [`IntGauge`], and decrement it when the returned value goes out of scope.
17#[inline]
18pub fn inc_scope(gauge: &IntGauge) -> GaugeInc {
19    gauge.inc();
20    GaugeInc { gauge: gauge.clone() }
21}
22
23pub trait IntGaugeExt {
24    fn inc_scope(&self) -> GaugeInc;
25}
26
27impl IntGaugeExt for IntGauge {
28    fn inc_scope(&self) -> GaugeInc {
29        inc_scope(self)
30    }
31}
32
33/// A scope guard for a timer,
34/// the total duration of which is written to a Histogram metric on drop.
35pub struct TimerGuard {
36    histogram: Histogram,
37    timer: Instant,
38}
39
40impl Drop for TimerGuard {
41    fn drop(&mut self) {
42        self.histogram.observe(self.timer.elapsed().as_secs_f64());
43    }
44}
45
46pub trait HistogramExt {
47    fn with_timer(self, timer: Instant) -> TimerGuard;
48}
49
50impl HistogramExt for Histogram {
51    fn with_timer(self, timer: Instant) -> TimerGuard {
52        TimerGuard { histogram: self, timer }
53    }
54}
spacetimedb/util/prometheus_handle.rs

spacetimedb/util/
prometheus_handle.rs
