libp2p_core/upgrade/
select.rs

1// Copyright 2018 Parity Technologies (UK) Ltd.
2//
3// Permission is hereby granted, free of charge, to any person obtaining a
4// copy of this software and associated documentation files (the "Software"),
5// to deal in the Software without restriction, including without limitation
6// the rights to use, copy, modify, merge, publish, distribute, sublicense,
7// and/or sell copies of the Software, and to permit persons to whom the
8// Software is furnished to do so, subject to the following conditions:
9//
10// The above copyright notice and this permission notice shall be included in
11// all copies or substantial portions of the Software.
12//
13// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
14// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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18// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
19// DEALINGS IN THE SOFTWARE.
20
21use std::iter::{Chain, Map};
22
23use either::Either;
24use futures::future;
25
26use crate::{
27    either::EitherFuture,
28    upgrade::{
29        InboundConnectionUpgrade, InboundUpgrade, OutboundConnectionUpgrade, OutboundUpgrade,
30        UpgradeInfo,
31    },
32};
33
34/// Upgrade that combines two upgrades into one. Supports all the protocols supported by either
35/// sub-upgrade.
36///
37/// The protocols supported by the first element have a higher priority.
38#[derive(Debug, Clone)]
39pub struct SelectUpgrade<A, B>(A, B);
40
41impl<A, B> SelectUpgrade<A, B> {
42    /// Combines two upgrades into an `SelectUpgrade`.
43    ///
44    /// The protocols supported by the first element have a higher priority.
45    pub fn new(a: A, b: B) -> Self {
46        SelectUpgrade(a, b)
47    }
48}
49
50impl<A, B> UpgradeInfo for SelectUpgrade<A, B>
51where
52    A: UpgradeInfo,
53    B: UpgradeInfo,
54{
55    type Info = Either<A::Info, B::Info>;
56    type InfoIter = Chain<
57        Map<<A::InfoIter as IntoIterator>::IntoIter, fn(A::Info) -> Self::Info>,
58        Map<<B::InfoIter as IntoIterator>::IntoIter, fn(B::Info) -> Self::Info>,
59    >;
60
61    fn protocol_info(&self) -> Self::InfoIter {
62        let a = self
63            .0
64            .protocol_info()
65            .into_iter()
66            .map(Either::Left as fn(A::Info) -> _);
67        let b = self
68            .1
69            .protocol_info()
70            .into_iter()
71            .map(Either::Right as fn(B::Info) -> _);
72
73        a.chain(b)
74    }
75}
76
77impl<C, A, B, TA, TB, EA, EB> InboundUpgrade<C> for SelectUpgrade<A, B>
78where
79    A: InboundUpgrade<C, Output = TA, Error = EA>,
80    B: InboundUpgrade<C, Output = TB, Error = EB>,
81{
82    type Output = future::Either<TA, TB>;
83    type Error = Either<EA, EB>;
84    type Future = EitherFuture<A::Future, B::Future>;
85
86    fn upgrade_inbound(self, sock: C, info: Self::Info) -> Self::Future {
87        match info {
88            Either::Left(info) => EitherFuture::First(self.0.upgrade_inbound(sock, info)),
89            Either::Right(info) => EitherFuture::Second(self.1.upgrade_inbound(sock, info)),
90        }
91    }
92}
93
94impl<C, A, B, TA, TB, EA, EB> InboundConnectionUpgrade<C> for SelectUpgrade<A, B>
95where
96    A: InboundConnectionUpgrade<C, Output = TA, Error = EA>,
97    B: InboundConnectionUpgrade<C, Output = TB, Error = EB>,
98{
99    type Output = future::Either<TA, TB>;
100    type Error = Either<EA, EB>;
101    type Future = EitherFuture<A::Future, B::Future>;
102
103    fn upgrade_inbound(self, sock: C, info: Self::Info) -> Self::Future {
104        match info {
105            Either::Left(info) => EitherFuture::First(self.0.upgrade_inbound(sock, info)),
106            Either::Right(info) => EitherFuture::Second(self.1.upgrade_inbound(sock, info)),
107        }
108    }
109}
110
111impl<C, A, B, TA, TB, EA, EB> OutboundUpgrade<C> for SelectUpgrade<A, B>
112where
113    A: OutboundUpgrade<C, Output = TA, Error = EA>,
114    B: OutboundUpgrade<C, Output = TB, Error = EB>,
115{
116    type Output = future::Either<TA, TB>;
117    type Error = Either<EA, EB>;
118    type Future = EitherFuture<A::Future, B::Future>;
119
120    fn upgrade_outbound(self, sock: C, info: Self::Info) -> Self::Future {
121        match info {
122            Either::Left(info) => EitherFuture::First(self.0.upgrade_outbound(sock, info)),
123            Either::Right(info) => EitherFuture::Second(self.1.upgrade_outbound(sock, info)),
124        }
125    }
126}
127
128impl<C, A, B, TA, TB, EA, EB> OutboundConnectionUpgrade<C> for SelectUpgrade<A, B>
129where
130    A: OutboundConnectionUpgrade<C, Output = TA, Error = EA>,
131    B: OutboundConnectionUpgrade<C, Output = TB, Error = EB>,
132{
133    type Output = future::Either<TA, TB>;
134    type Error = Either<EA, EB>;
135    type Future = EitherFuture<A::Future, B::Future>;
136
137    fn upgrade_outbound(self, sock: C, info: Self::Info) -> Self::Future {
138        match info {
139            Either::Left(info) => EitherFuture::First(self.0.upgrade_outbound(sock, info)),
140            Either::Right(info) => EitherFuture::Second(self.1.upgrade_outbound(sock, info)),
141        }
142    }
143}
libp2p_core/upgrade/select.rs

libp2p_core/upgrade/
select.rs
