tk_pool/
metrics.rs

1//! Metrics trait and no-op implementation
2
3/// An object implementing trait may collect metrics of a connection pool
4pub trait Collect: Clone + Send + Sync {
5    /// We started establishing connection
6    ///
7    /// This pairs either with ``connection`` on success
8    /// or ``connection_abort`` and ``connection_error`` on error
9    fn connection_attempt(&self) {}
10    /// Error establishing connection
11    fn connection_error(&self) {}
12
13    /// Aborted connection attempt (name changed, and doesn't include address)
14    fn connection_abort(&self) {}
15    /// Connection established successfully
16    fn connection(&self) {}
17    /// Connection closed (usully means name changed)
18    fn disconnect(&self) {}
19
20    /// Host address added to a blacklist (i.e. connection error)
21    fn blacklist_add(&self) {}
22    /// Host address removed from a blacklist
23    ///
24    /// Note this callback is only called when we're searching for a new
25    /// connection and all others are busy. I.e. unlisting a host from a
26    /// blacklist may be delayed arbitrarily when not under backpressure.
27    /// This may be fixed in future.
28    fn blacklist_remove(&self) {}
29
30    /// Request queued in the internal queue
31    fn request_queued(&self) {}
32    /// Request unqueued from the internal queue and forwarded to a sink
33    ///
34    /// Note: this might not mean that request is already sent as we can't
35    /// control the underlying sinks used.
36    fn request_forwarded(&self) {}
37
38    /// Connection pool is closed
39    fn pool_closed(&self) {}
40}
41
42
43/// A object implementing Collect which is not interested in actual metrics
44#[derive(Debug, Clone)]
45pub struct Noop;
46
47impl Collect for Noop {}
tk_pool/metrics.rs

tk_pool/
metrics.rs
