1  //! Check health of the node.
 2  
 3  use std::{sync::Arc, time::Duration};
 4  
 5  use apibara_node::db::{
 6      libmdbx::{Environment, EnvironmentKind, Error as MdbxError},
 7      MdbxTransactionExt,
 8  };
 9  use tokio_util::sync::CancellationToken;
10  use tonic_health::pb::health_server::{Health, HealthServer};
11  use tracing::warn;
12  
13  use crate::db::tables;
14  
15  pub struct HealthReporter<E: EnvironmentKind> {
16      db: Arc<Environment<E>>,
17      _reporter: tonic_health::server::HealthReporter,
18  }
19  
20  impl<E> HealthReporter<E>
21  where
22      E: EnvironmentKind,
23  {
24      pub fn new(db: Arc<Environment<E>>) -> (Self, HealthServer<impl Health>) {
25          let (reporter, service) = tonic_health::server::health_reporter();
26          (
27              HealthReporter {
28                  db,
29                  _reporter: reporter,
30              },
31              service,
32          )
33      }
34  
35      pub async fn start(&mut self, ct: CancellationToken) {
36          let interval = Duration::from_secs(1);
37          loop {
38              if ct.is_cancelled() {
39                  return;
40              }
41  
42              if self.check_db().is_ok() {
43                  self.set_serving().await;
44              } else {
45                  self.set_not_serving().await;
46              }
47  
48              tokio::time::sleep(interval).await;
49          }
50      }
51  
52      fn check_db(&self) -> Result<(), MdbxError> {
53          let txn = self.db.begin_ro_txn()?;
54          // access one table to see if db access is working
55          let mut cursor = txn.open_table::<tables::BlockHeaderTable>()?.cursor()?;
56          cursor.last()?;
57          txn.commit()?;
58          Ok(())
59      }
60  
61      async fn set_serving(&mut self) {
62          /*
63          self.reporter
64              .set_serving::<pb::node_server::NodeServer<NodeServer<E>>>()
65              .await
66          */
67      }
68  
69      async fn set_not_serving(&mut self) {
70          warn!("server is not serving");
71          /*
72          self.reporter
73              .set_not_serving::<pb::node_server::NodeServer<NodeServer<E>>>()
74              .await
75          */
76      }
77  }