1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172

/*
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */

//! Test connectors that never return data

use aws_smithy_async::future::never::Never;
use aws_smithy_runtime_api::client::http::{
    HttpClient, HttpConnector, HttpConnectorFuture, HttpConnectorSettings, SharedHttpConnector,
};
use aws_smithy_runtime_api::client::orchestrator::HttpRequest;
use aws_smithy_runtime_api::client::runtime_components::RuntimeComponents;
use aws_smithy_runtime_api::shared::IntoShared;
use std::sync::atomic::{AtomicUsize, Ordering};
use std::sync::Arc;

/// A client that will never respond.
///
/// Returned futures will return `Pending` forever
#[derive(Clone, Debug, Default)]
pub struct NeverClient {
    invocations: Arc<AtomicUsize>,
}

impl NeverClient {
    /// Create a new never connector.
    pub fn new() -> Self {
        Default::default()
    }

    /// Returns the number of invocations made to this connector.
    pub fn num_calls(&self) -> usize {
        self.invocations.load(Ordering::SeqCst)
    }
}

impl HttpConnector for NeverClient {
    fn call(&self, _request: HttpRequest) -> HttpConnectorFuture {
        self.invocations.fetch_add(1, Ordering::SeqCst);
        HttpConnectorFuture::new(async move {
            Never::new().await;
            unreachable!()
        })
    }
}

impl HttpClient for NeverClient {
    fn http_connector(
        &self,
        _: &HttpConnectorSettings,
        _: &RuntimeComponents,
    ) -> SharedHttpConnector {
        self.clone().into_shared()
    }
}

/// A TCP connector that never connects.
// In the future, this can be available for multiple hyper version feature flags, with the impls gated between individual features
#[cfg(feature = "connector-hyper-0-14-x")]
#[derive(Clone, Debug, Default)]
pub struct NeverTcpConnector;

#[cfg(feature = "connector-hyper-0-14-x")]
impl NeverTcpConnector {
    /// Creates a new `NeverTcpConnector`.
    pub fn new() -> Self {
        Self
    }
}

#[cfg(feature = "connector-hyper-0-14-x")]
impl hyper_0_14::service::Service<http::Uri> for NeverTcpConnector {
    type Response = connection::NeverTcpConnection;
    type Error = aws_smithy_runtime_api::box_error::BoxError;
    type Future = std::pin::Pin<
        Box<dyn std::future::Future<Output = Result<Self::Response, Self::Error>> + Send + Sync>,
    >;

    fn poll_ready(
        &mut self,
        _: &mut std::task::Context<'_>,
    ) -> std::task::Poll<Result<(), Self::Error>> {
        std::task::Poll::Ready(Ok(()))
    }

    fn call(&mut self, _: http::Uri) -> Self::Future {
        Box::pin(async {
            Never::new().await;
            unreachable!()
        })
    }
}

#[cfg(feature = "connector-hyper-0-14-x")]
mod connection {
    use hyper_0_14::client::connect::{Connected, Connection};
    use std::io::Error;
    use std::pin::Pin;
    use std::task::{Context, Poll};
    use tokio::io::{AsyncRead, AsyncWrite, ReadBuf};

    /// A connection type that appeases hyper's trait bounds for a TCP connector, but will panic if any of its traits are used.
    #[non_exhaustive]
    #[derive(Debug, Default)]
    pub struct NeverTcpConnection;

    impl Connection for NeverTcpConnection {
        fn connected(&self) -> Connected {
            unreachable!()
        }
    }

    impl AsyncRead for NeverTcpConnection {
        fn poll_read(
            self: Pin<&mut Self>,
            _cx: &mut Context<'_>,
            _buf: &mut ReadBuf<'_>,
        ) -> Poll<std::io::Result<()>> {
            unreachable!()
        }
    }

    impl AsyncWrite for NeverTcpConnection {
        fn poll_write(
            self: Pin<&mut Self>,
            _cx: &mut Context<'_>,
            _buf: &[u8],
        ) -> Poll<Result<usize, Error>> {
            unreachable!()
        }

        fn poll_flush(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), Error>> {
            unreachable!()
        }

        fn poll_shutdown(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), Error>> {
            unreachable!()
        }
    }
}

#[cfg(all(test, feature = "connector-hyper-0-14-x"))]
#[tokio::test]
async fn never_tcp_connector_plugs_into_hyper_014() {
    use super::*;
    use crate::client::http::hyper_014::HyperClientBuilder;
    use aws_smithy_async::rt::sleep::TokioSleep;
    use aws_smithy_async::time::SystemTimeSource;
    use aws_smithy_runtime_api::client::runtime_components::RuntimeComponentsBuilder;
    use std::time::Duration;

    // it should compile
    let client = HyperClientBuilder::new().build(NeverTcpConnector::new());
    let components = RuntimeComponentsBuilder::for_tests()
        .with_sleep_impl(Some(TokioSleep::new()))
        .with_time_source(Some(SystemTimeSource::new()))
        .build()
        .unwrap();
    let http_connector = client.http_connector(
        &HttpConnectorSettings::builder()
            .connect_timeout(Duration::from_millis(100))
            .build(),
        &components,
    );

    let err = http_connector
        .call(HttpRequest::get("http://fakeuri.com").unwrap())
        .await
        .expect_err("it should time out");
    assert!(dbg!(err).is_timeout());
}