iota_network_stack/callback/
service.rs

1// Copyright (c) Mysten Labs, Inc.
2// Modifications Copyright (c) 2024 IOTA Stiftung
3// SPDX-License-Identifier: Apache-2.0
4
5use std::task::{Context, Poll};
6
7use http::{Request, Response};
8use tower::Service;
9
10use super::{CallbackLayer, MakeCallbackHandler, ResponseBody, ResponseFuture};
11
12/// Middleware that adds callbacks to a [`Service`].
13///
14/// See the [module docs](crate::callback) for an example.
15///
16/// [`Service`]: tower::Service
17#[derive(Debug, Clone, Copy)]
18pub struct Callback<S, M> {
19    pub(crate) inner: S,
20    pub(crate) make_callback_handler: M,
21}
22
23impl<S, M> Callback<S, M> {
24    /// Create a new [`Callback`].
25    pub fn new(inner: S, make_callback_handler: M) -> Self {
26        Self {
27            inner,
28            make_callback_handler,
29        }
30    }
31
32    /// Returns a new [`Layer`] that wraps services with a [`CallbackLayer`]
33    /// middleware.
34    ///
35    /// [`Layer`]: tower::layer::Layer
36    pub fn layer(make_handler: M) -> CallbackLayer<M>
37    where
38        M: MakeCallbackHandler,
39    {
40        CallbackLayer::new(make_handler)
41    }
42
43    /// Gets a reference to the underlying service.
44    pub fn inner(&self) -> &S {
45        &self.inner
46    }
47
48    /// Gets a mutable reference to the underlying service.
49    pub fn inner_mut(&mut self) -> &mut S {
50        &mut self.inner
51    }
52
53    /// Consumes `self`, returning the underlying service.
54    pub fn into_inner(self) -> S {
55        self.inner
56    }
57}
58
59impl<S, M, RequestBody, ResponseBodyT> Service<Request<RequestBody>> for Callback<S, M>
60where
61    S: Service<
62            Request<RequestBody>,
63            Response = Response<ResponseBodyT>,
64            Error: std::fmt::Display + 'static,
65        >,
66    M: MakeCallbackHandler,
67    RequestBody: http_body::Body<Error: std::fmt::Display + 'static>,
68    ResponseBodyT: http_body::Body<Error: std::fmt::Display + 'static>,
69{
70    type Response = Response<ResponseBody<ResponseBodyT, M::Handler>>;
71    type Error = S::Error;
72    type Future = ResponseFuture<S::Future, M::Handler>;
73
74    fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
75        self.inner.poll_ready(cx)
76    }
77
78    fn call(&mut self, request: Request<RequestBody>) -> Self::Future {
79        let (head, body) = request.into_parts();
80        let handler = self.make_callback_handler.make_handler(&head);
81        let request = Request::from_parts(head, body);
82
83        ResponseFuture {
84            inner: self.inner.call(request),
85            handler: Some(handler),
86        }
87    }
88}
iota_network_stack/callback/service.rs

iota_network_stack/callback/
service.rs
