zenoh 1.9.0

Zenoh: The Zero Overhead Pub/Sub/Query Protocol.
Documentation 
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
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241

//
// Copyright (c) 2024 ZettaScale Technology
//
// This program and the accompanying materials are made available under the
// terms of the Eclipse Public License 2.0 which is available at
// http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
// which is available at https://www.apache.org/licenses/LICENSE-2.0.
//
// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
//
// Contributors:
//   ZettaScale Zenoh Team, <zenoh@zettascale.tech>
//

use std::{
    future::{Future, IntoFuture},
    pin::Pin,
    time::Duration,
};

use async_trait::async_trait;
#[cfg(all(feature = "unstable", feature = "internal"))]
use tokio::sync::oneshot::Receiver;
use zenoh_core::{Resolvable, Wait};
use zenoh_result::ZResult;
use zenoh_runtime::ZRuntime;

/// A builder for close operations, returned by the
/// [`Session::close`](crate::Session::close) method.
// NOTE: `Closeable` is only pub(crate) because it is a zenoh-internal trait, so we don't
// care about the `private_bounds` lint in this particular case.
#[allow(private_bounds)]
#[must_use = "Resolvables do nothing unless you resolve them using `.await` or `zenoh::Wait::wait`"]
pub struct CloseBuilder<TCloseable: Closeable> {
    closee: TCloseable::TClosee,
    timeout: Duration,
    close_args: <TCloseable::TClosee as Closee>::CloseArgs,
}

// NOTE: `Closeable` is only pub(crate) because it is a zenoh-internal trait, so we don't
// care about the `private_bounds` lint in this particular case.
#[allow(private_bounds)]
impl<TCloseable: Closeable> CloseBuilder<TCloseable> {
    pub(crate) fn new(closeable: &'_ TCloseable) -> Self {
        Self {
            closee: closeable.get_closee(),
            timeout: Duration::from_secs(10),
            close_args: <TCloseable::TClosee as Closee>::CloseArgs::default(),
        }
    }

    #[cfg(all(feature = "unstable", feature = "internal"))]
    /// Set the timeout for the close operation
    ///
    /// # Arguments
    ///
    /// * `timeout` - The timeout value for the close operation (10s by default)
    ///
    #[doc(hidden)]
    pub fn timeout(mut self, timeout: Duration) -> Self {
        self.timeout = timeout;
        self
    }

    #[cfg(all(feature = "unstable", feature = "internal"))]
    /// Run the Close operation concurrently
    #[doc(hidden)]
    pub fn in_background(
        self,
    ) -> BackgroundCloseBuilder<<CloseBuilder<TCloseable> as Resolvable>::To> {
        BackgroundCloseBuilder::new(self.into_future())
    }
}

impl<TCloseable: Closeable> Resolvable for CloseBuilder<TCloseable> {
    type To = ZResult<()>;
}

impl<TCloseable: Closeable> Wait for CloseBuilder<TCloseable> {
    fn wait(self) -> Self::To {
        let future = self.into_future();
        match tokio::runtime::Handle::try_current() {
            Ok(_) => {
                tracing::trace!("tokio TLS available, closing closeable directly");
                ZRuntime::Net.block_in_place(future)
            }
            Err(e) if e.is_missing_context() => {
                tracing::trace!("tokio TLS is just missing, closing closeable directly");
                ZRuntime::Net.block_in_place(future)
            }
            Err(_) => {
                #[cfg(nolocal_thread_not_available)]
                panic!("Close when thread-local storage is unavailable (typically in atexit()) does not work for this Rust 1.85..1.85.1, see https://github.com/rust-lang/rust/issues/138696");

                #[cfg(not(nolocal_thread_not_available))]
                {
                    let evaluate = move || {
                        // NOTE: tracing logger also panics if used inside atexit() handler!!!
                        tracing::trace!(
                            "tokio TLS NOT available, closing closeable in separate thread"
                        );
                        ZRuntime::Net.block_in_place(future)
                    };
                    std::thread::spawn(evaluate)
                        .join()
                        .expect("Error spawning atexit-safe thread")
                }
            }
        }
    }
}

impl<TCloseable: Closeable> IntoFuture for CloseBuilder<TCloseable> {
    type Output = <Self as Resolvable>::To;
    type IntoFuture = Pin<Box<dyn Future<Output = <Self as IntoFuture>::Output> + Send>>;

    fn into_future(self) -> Self::IntoFuture {
        Box::pin(
            async move {
                if tokio::time::timeout(self.timeout, self.closee.close_inner(self.close_args))
                    .await
                    .is_err()
                {
                    bail!("close operation timed out!")
                }
                Ok(())
            }
            .into_future(),
        )
    }
}

#[cfg(all(feature = "unstable", feature = "internal"))]
/// A builder for close operations running in the background
#[doc(hidden)]
pub struct BackgroundCloseBuilder<TOutput: Send + 'static> {
    inner: Pin<Box<dyn Future<Output = TOutput> + Send>>,
}

#[cfg(all(feature = "unstable", feature = "internal"))]
#[doc(hidden)]
impl<TOutput: Send + 'static> BackgroundCloseBuilder<TOutput> {
    fn new(inner: Pin<Box<dyn Future<Output = TOutput> + Send>>) -> Self {
        Self { inner }
    }
}

#[cfg(all(feature = "unstable", feature = "internal"))]
impl<TOutput: Send + 'static> Resolvable for BackgroundCloseBuilder<TOutput> {
    type To = NolocalJoinHandle<TOutput>;
}

#[cfg(all(feature = "unstable", feature = "internal"))]
impl<TOutput: Send + 'static> Wait for BackgroundCloseBuilder<TOutput> {
    fn wait(self) -> Self::To {
        ZRuntime::Net.block_in_place(self.into_future())
    }
}

#[cfg(all(feature = "unstable", feature = "internal"))]
impl<TOutput: Send + 'static> IntoFuture for BackgroundCloseBuilder<TOutput> {
    type Output = <Self as Resolvable>::To;
    type IntoFuture = Pin<Box<dyn Future<Output = <Self as IntoFuture>::Output> + Send>>;

    fn into_future(self) -> Self::IntoFuture {
        Box::pin(
            async move {
                let (tx, rx) = tokio::sync::oneshot::channel();
                ZRuntime::Net.spawn(async move {
                    if tx.send(self.inner.await).is_err() {
                        panic!("BackgroundCloseBuilder: critical error sending the result");
                    }
                });
                NolocalJoinHandle::new(rx)
            }
            .into_future(),
        )
    }
}

#[cfg(all(feature = "unstable", feature = "internal"))]
#[doc(hidden)]
pub struct NolocalJoinHandle<TOutput: Send + 'static> {
    rx: Receiver<TOutput>,
}

#[cfg(all(feature = "unstable", feature = "internal"))]
impl<TOutput: Send + 'static> NolocalJoinHandle<TOutput> {
    fn new(rx: Receiver<TOutput>) -> Self {
        Self { rx }
    }
}

#[cfg(all(feature = "unstable", feature = "internal"))]
impl<TOutput: Send + 'static> Resolvable for NolocalJoinHandle<TOutput> {
    type To = TOutput;
}

#[cfg(all(feature = "unstable", feature = "internal"))]
impl<TOutput: Send + 'static> Wait for NolocalJoinHandle<TOutput> {
    fn wait(self) -> Self::To {
        ZRuntime::Net.block_in_place(self.into_future())
    }
}

#[cfg(all(feature = "unstable", feature = "internal"))]
impl<TOutput: Send + 'static> IntoFuture for NolocalJoinHandle<TOutput> {
    type Output = <Self as Resolvable>::To;
    type IntoFuture = Pin<Box<dyn Future<Output = <Self as IntoFuture>::Output> + Send>>;

    fn into_future(self) -> Self::IntoFuture {
        Box::pin(
            async move {
                self.rx
                    .await
                    .expect("NolocalJoinHandle: critical error receiving the result")
            }
            .into_future(),
        )
    }
}

#[async_trait]
pub(crate) trait Closee: Send + Sync + 'static {
    type CloseArgs: Default + Send + Sync;
    async fn close_inner(&self, close_arg: Self::CloseArgs);
}

pub(crate) trait Closeable {
    type TClosee: Closee;
    fn get_closee(&self) -> Self::TClosee;
}

impl CloseBuilder<crate::Session> {
    #[zenoh_macros::internal_or_unstable]
    /// Block in undeclare operation until all currently running zenoh entities' callbacks (if any) return.
    pub fn wait_callbacks(mut self) -> Self {
        self.close_args.wait_callbacks = true;
        self
    }
}