script/
routed_promise.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5use js::context::JSContext;
6use script_bindings::reflector::DomObject;
7use serde::Serialize;
8use serde::de::DeserializeOwned;
9use servo_base::generic_channel::GenericCallback;
10
11use crate::dom::bindings::refcounted::{Trusted, TrustedPromise};
12use crate::dom::promise::RootedPromise;
13use crate::tasks::task_source::TaskSource;
14
15pub(crate) trait RoutedPromiseListener<R: Serialize + DeserializeOwned + Send> {
16    fn handle_response(&self, cx: &mut JSContext, response: R, promise: &RootedPromise);
17}
18
19pub(crate) struct RoutedPromiseContext<
20    R: Serialize + DeserializeOwned + Send,
21    T: RoutedPromiseListener<R> + DomObject,
22> {
23    trusted: TrustedPromise,
24    receiver: Trusted<T>,
25    _phantom: std::marker::PhantomData<R>,
26}
27
28impl<R: Serialize + DeserializeOwned + Send, T: RoutedPromiseListener<R> + DomObject>
29    RoutedPromiseContext<R, T>
30{
31    fn response(self, cx: &mut JSContext, response: R) {
32        let promise = self.trusted.root(cx);
33        self.receiver.root().handle_response(cx, response, &promise);
34    }
35}
36
37pub(crate) fn callback_promise<
38    R: Serialize + DeserializeOwned + Send + 'static,
39    T: RoutedPromiseListener<R> + DomObject + 'static,
40>(
41    promise: &RootedPromise,
42    receiver: &T,
43    task_source: TaskSource,
44) -> GenericCallback<R> {
45    let task_source = task_source.to_sendable();
46    let mut trusted: Option<TrustedPromise> = Some(TrustedPromise::from(promise));
47    let trusted_receiver = Trusted::new(receiver);
48    GenericCallback::new(move |message| {
49        let trusted = if let Some(trusted) = trusted.take() {
50            trusted
51        } else {
52            error!("RoutedPromiseListener callback called twice!");
53            return;
54        };
55
56        let context = RoutedPromiseContext {
57            trusted,
58            receiver: trusted_receiver.clone(),
59            _phantom: Default::default(),
60        };
61        task_source.queue(task!(routed_promise_task: move|cx| {
62            context.response(cx, message.unwrap());
63        }));
64    })
65    .expect("Could not create callback in script.")
66}
script/routed_promise.rs

script/
routed_promise.rs
