Line data    Source code

       1              : use std::convert::Infallible;
       2              : 
       3              : use anyhow::bail;
       4              : use tokio_util::sync::CancellationToken;
       5              : use tracing::{info, warn};
       6              : 
       7              : use crate::metrics::{Metrics, ServiceInfo};
       8              : 
       9              : /// Handle unix signals appropriately.
      10            0 : pub async fn handle<F>(
      11            0 :     token: CancellationToken,
      12            0 :     mut refresh_config: F,
      13            0 : ) -> anyhow::Result<Infallible>
      14            0 : where
      15            0 :     F: FnMut(),
      16            0 : {
      17              :     use tokio::signal::unix::{SignalKind, signal};
      18              : 
      19            0 :     let mut hangup = signal(SignalKind::hangup())?;
      20            0 :     let mut interrupt = signal(SignalKind::interrupt())?;
      21            0 :     let mut terminate = signal(SignalKind::terminate())?;
      22              : 
      23              :     loop {
      24            0 :         tokio::select! {
      25              :             // Hangup is commonly used for config reload.
      26            0 :             _ = hangup.recv() => {
      27            0 :                 info!("received SIGHUP");
      28            0 :                 refresh_config();
      29              :             }
      30              :             // Shut down the whole application.
      31            0 :             _ = interrupt.recv() => {
      32            0 :                 warn!("received SIGINT, exiting immediately");
      33            0 :                 Metrics::get().service.info.set_label(ServiceInfo::terminating());
      34            0 :                 bail!("interrupted");
      35              :             }
      36            0 :             _ = terminate.recv() => {
      37            0 :                 warn!("received SIGTERM, shutting down once all existing connections have closed");
      38            0 :                 Metrics::get().service.info.set_label(ServiceInfo::terminating());
      39            0 :                 token.cancel();
      40              :             }
      41              :         }
      42              :     }
      43            0 : }