reqwest_lb/
discovery.rs

1use futures::Stream;
2use std::fmt::Debug;
3use std::{
4    pin::Pin,
5    task::{Context, Poll},
6};
7
8pub trait Discovery: sealed::Sealed {
9    ///
10    /// element key
11    ///
12    type Key: Debug;
13
14    ///
15    /// element type
16    ///
17    type Element;
18
19    ///
20    /// poll element change error type
21    ///
22    type Error;
23
24    ///
25    /// poll element change event(s)
26    ///
27    fn poll_change(
28        self: Pin<&mut Self>,
29        cx: &mut Context<'_>,
30    ) -> Poll<Option<Result<Change<Self::Key, Self::Element>, Self::Error>>>;
31}
32
33pub enum Change<K, V> {
34    ///
35    /// discovery element insert event
36    ///
37    Insert(K, V),
38
39    ///
40    /// discovery element remove event
41    ///
42    Remove(K),
43
44    ///
45    /// discovery element initialized event
46    ///
47    Initialized,
48}
49
50impl<S, K, T, E> sealed::Sealed for S where S: Stream<Item = Result<Change<K, T>, E>> {}
51
52impl<S, K, T, E> Discovery for S
53where
54    S: Stream<Item = Result<Change<K, T>, E>>,
55    K: Debug,
56{
57    type Key = K;
58
59    type Element = T;
60
61    type Error = E;
62
63    fn poll_change(
64        self: Pin<&mut Self>,
65        cx: &mut Context<'_>,
66    ) -> Poll<Option<Result<Change<Self::Key, Self::Element>, Self::Error>>> {
67        self.poll_next(cx)
68    }
69}
70
71pub type BoxDiscovery<'a, K, I, E> =
72    Pin<Box<dyn Stream<Item = Result<Change<K, I>, E>> + Send + Sync + 'a>>;
73
74mod sealed {
75    pub trait Sealed {}
76}
reqwest_lb/discovery.rs

reqwest_lb/
discovery.rs
