chromiumoxide/handler/
target_message_future.rs

1use futures::channel::{
2    mpsc,
3    oneshot::{self, channel as oneshot_channel},
4};
5use pin_project_lite::pin_project;
6use std::future::Future;
7use std::pin::Pin;
8use std::task::{Context, Poll};
9
10use crate::handler::target::TargetMessage;
11use crate::{error::Result, ArcHttpRequest};
12
13type TargetSender = mpsc::Sender<TargetMessage>;
14
15pin_project! {
16    pub struct TargetMessageFuture<T> {
17        #[pin]
18        rx_request: oneshot::Receiver<T>,
19        #[pin]
20        target_sender: mpsc::Sender<TargetMessage>,
21        message: Option<TargetMessage>,
22    }
23}
24
25impl<T> TargetMessageFuture<T> {
26    pub fn new(
27        target_sender: TargetSender,
28        message: TargetMessage,
29        rx_request: oneshot::Receiver<T>,
30    ) -> Self {
31        Self {
32            target_sender,
33            rx_request,
34            message: Some(message),
35        }
36    }
37
38    pub fn wait_for_navigation(target_sender: TargetSender) -> TargetMessageFuture<ArcHttpRequest> {
39        let (tx, rx_request) = oneshot_channel();
40
41        let message = TargetMessage::WaitForNavigation(tx);
42
43        TargetMessageFuture::new(target_sender, message, rx_request)
44    }
45}
46
47impl<T> Future for TargetMessageFuture<T> {
48    type Output = Result<T>;
49
50    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
51        let mut this = self.project();
52
53        if this.message.is_some() {
54            match this.target_sender.poll_ready(cx) {
55                Poll::Ready(Err(e)) => Poll::Ready(Err(e.into())),
56                Poll::Ready(Ok(_)) => {
57                    let message = this.message.take().expect("existence checked above");
58                    this.target_sender.start_send(message)?;
59
60                    cx.waker().wake_by_ref();
61                    Poll::Pending
62                }
63                Poll::Pending => Poll::Pending,
64            }
65        } else {
66            this.rx_request.as_mut().poll(cx).map_err(Into::into)
67        }
68    }
69}