Log exec

log_exec.rs

use std::time::Duration;
use std::time::Instant;

// Executes `func` and logs warning or error message if it takes longer than specified.
pub fn log_exec<F, T>(label: &str, warn_millis: u64, error_millis: u64, func: F) -> T where F: FnOnce() -> T {
    let warn_duration = Duration::from_millis(warn_millis);
    let error_duration = Duration::from_millis(error_millis);

    let start = Instant::now();
    let output = func();
    let end = Instant::now();
    let duration = end - start;

    if duration > error_duration {
        error!("`{}` took much longer than expected: {:2.2} secs", label, to_secs(duration));
    } else if duration > warn_duration {
        warn!("`{}` took longer than expected: {:2.2} secs", label, to_secs(duration));
    }

    output
}

fn to_secs(duration: Duration) -> f64 {
    let secs = duration.as_secs() as f64;
    let nanos = duration.subsec_nanos() as f64;
    secs + nanos / 1000_000_000.0
}