Line data    Source code

       1              : //! A timestamp captured at process startup to identify restarts of the process, e.g., in logs and metrics.
       2              : 
       3              : use chrono::Utc;
       4              : 
       5              : use super::register_uint_gauge;
       6              : use std::fmt::Display;
       7              : 
       8              : pub struct LaunchTimestamp(chrono::DateTime<Utc>);
       9              : 
      10              : impl LaunchTimestamp {
      11         1745 :     pub fn generate() -> Self {
      12         1745 :         LaunchTimestamp(Utc::now())
      13         1745 :     }
      14              : }
      15              : 
      16              : impl Display for LaunchTimestamp {
      17         1569 :     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
      18         1569 :         write!(f, "{}", self.0)
      19         1569 :     }
      20              : }
      21              : 
      22          604 : pub fn set_launch_timestamp_metric(launch_ts: &'static LaunchTimestamp) {
      23          604 :     let millis_since_epoch: u64 = launch_ts
      24          604 :         .0
      25          604 :         .timestamp_millis()
      26          604 :         .try_into()
      27          604 :         .expect("we're after the epoch, this should be positive");
      28          604 :     let metric = register_uint_gauge!(
      29          604 :         "libmetrics_launch_timestamp",
      30          604 :         "Timestamp (millis since epoch) at wich the process launched."
      31          604 :     )
      32          604 :     .unwrap();
      33          604 :     metric.set(millis_since_epoch);
      34          604 : }