jsonrpsee_core/middleware/layer/
either.rs

1// Copyright 2019-2021 Parity Technologies (UK) Ltd.
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26
27//! [`tower::util::Either`] but
28//! adjusted to satisfy the trait bound [`RpcServiceT].
29//!
30//! NOTE: This is introduced because it doesn't
31//! work to implement tower::Layer for
32//! external types such as future::Either.
33
34use crate::middleware::{Batch, Notification, RpcServiceT};
35use jsonrpsee_types::Request;
36
37/// [`tower::util::Either`] but
38/// adjusted to satisfy the trait bound [`RpcServiceT].
39#[derive(Clone, Debug)]
40pub enum Either<A, B> {
41	/// One type of backing [`RpcServiceT`].
42	Left(A),
43	/// The other type of backing [`RpcServiceT`].
44	Right(B),
45}
46
47impl<S, A, B> tower::Layer<S> for Either<A, B>
48where
49	A: tower::Layer<S>,
50	B: tower::Layer<S>,
51{
52	type Service = Either<A::Service, B::Service>;
53
54	fn layer(&self, inner: S) -> Self::Service {
55		match self {
56			Either::Left(layer) => Either::Left(layer.layer(inner)),
57			Either::Right(layer) => Either::Right(layer.layer(inner)),
58		}
59	}
60}
61
62impl<A, B> RpcServiceT for Either<A, B>
63where
64	A: RpcServiceT + Send,
65	B: RpcServiceT<
66			MethodResponse = A::MethodResponse,
67			NotificationResponse = A::NotificationResponse,
68			BatchResponse = A::BatchResponse,
69		> + Send,
70{
71	type BatchResponse = A::BatchResponse;
72	type MethodResponse = A::MethodResponse;
73	type NotificationResponse = A::NotificationResponse;
74
75	fn call<'a>(&self, request: Request<'a>) -> impl Future<Output = Self::MethodResponse> + Send + 'a {
76		match self {
77			Either::Left(service) => futures_util::future::Either::Left(service.call(request)),
78			Either::Right(service) => futures_util::future::Either::Right(service.call(request)),
79		}
80	}
81
82	fn batch<'a>(&self, batch: Batch<'a>) -> impl Future<Output = Self::BatchResponse> + Send + 'a {
83		match self {
84			Either::Left(service) => futures_util::future::Either::Left(service.batch(batch)),
85			Either::Right(service) => futures_util::future::Either::Right(service.batch(batch)),
86		}
87	}
88
89	fn notification<'a>(&self, n: Notification<'a>) -> impl Future<Output = Self::NotificationResponse> + Send + 'a {
90		match self {
91			Either::Left(service) => futures_util::future::Either::Left(service.notification(n)),
92			Either::Right(service) => futures_util::future::Either::Right(service.notification(n)),
93		}
94	}
95}
jsonrpsee_core/middleware/layer/either.rs

jsonrpsee_core/middleware/layer/
either.rs
