yew_agent/oneshot/
provider.rs

1use core::fmt;
2use std::any::type_name;
3use std::cell::RefCell;
4use std::rc::Rc;
5
6use serde::{Deserialize, Serialize};
7use yew::prelude::*;
8
9use super::{Oneshot, OneshotBridge, OneshotSpawner};
10use crate::utils::get_next_id;
11use crate::worker::WorkerProviderProps;
12use crate::{Bincode, Codec, Reach};
13
14pub(crate) struct OneshotProviderState<T>
15where
16    T: Oneshot + 'static,
17{
18    id: usize,
19    spawn_bridge_fn: Rc<dyn Fn() -> OneshotBridge<T>>,
20    reach: Reach,
21    held_bridge: Rc<RefCell<Option<OneshotBridge<T>>>>,
22}
23
24impl<T> fmt::Debug for OneshotProviderState<T>
25where
26    T: Oneshot,
27{
28    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
29        f.write_str(type_name::<Self>())
30    }
31}
32
33impl<T> OneshotProviderState<T>
34where
35    T: Oneshot,
36{
37    fn get_held_bridge(&self) -> OneshotBridge<T> {
38        let mut held_bridge = self.held_bridge.borrow_mut();
39
40        match held_bridge.as_mut() {
41            Some(m) => m.fork(),
42            None => {
43                let bridge = (self.spawn_bridge_fn)();
44                *held_bridge = Some(bridge.fork());
45                bridge
46            }
47        }
48    }
49
50    /// Creates a bridge, uses "fork" for public agents.
51    pub fn create_bridge(&self) -> OneshotBridge<T> {
52        match self.reach {
53            Reach::Public => {
54                let held_bridge = self.get_held_bridge();
55                held_bridge.fork()
56            }
57            Reach::Private => (self.spawn_bridge_fn)(),
58        }
59    }
60}
61
62impl<T> Clone for OneshotProviderState<T>
63where
64    T: Oneshot,
65{
66    fn clone(&self) -> Self {
67        Self {
68            id: self.id,
69            spawn_bridge_fn: self.spawn_bridge_fn.clone(),
70            reach: self.reach,
71            held_bridge: self.held_bridge.clone(),
72        }
73    }
74}
75
76impl<T> PartialEq for OneshotProviderState<T>
77where
78    T: Oneshot,
79{
80    fn eq(&self, rhs: &Self) -> bool {
81        self.id == rhs.id
82    }
83}
84
85/// The Oneshot Agent Provider.
86///
87/// This component provides its children access to an oneshot agent.
88#[function_component]
89pub fn OneshotProvider<T, C = Bincode>(props: &WorkerProviderProps) -> Html
90where
91    T: Oneshot + 'static,
92    T::Input: Serialize + for<'de> Deserialize<'de> + 'static,
93    T::Output: Serialize + for<'de> Deserialize<'de> + 'static,
94    C: Codec + 'static,
95{
96    let WorkerProviderProps {
97        children,
98        path,
99        lazy,
100        module,
101        reach,
102    } = props.clone();
103
104    // Creates a spawning function so Codec is can be erased from contexts.
105    let spawn_bridge_fn: Rc<dyn Fn() -> OneshotBridge<T>> = {
106        let path = path.clone();
107        Rc::new(move || {
108            OneshotSpawner::<T>::new()
109                .as_module(module)
110                .encoding::<C>()
111                .spawn(&path)
112        })
113    };
114
115    let state = {
116        use_memo((path, lazy, reach), move |(_path, lazy, reach)| {
117            let state = OneshotProviderState::<T> {
118                id: get_next_id(),
119                spawn_bridge_fn,
120                reach: *reach,
121                held_bridge: Rc::default(),
122            };
123
124            if *reach == Reach::Public && !*lazy {
125                state.get_held_bridge();
126            }
127            state
128        })
129    };
130
131    html! {
132        <ContextProvider<OneshotProviderState<T>> context={(*state).clone()}>
133            {children}
134        </ContextProvider<OneshotProviderState<T>>>
135    }
136}
yew_agent/oneshot/provider.rs

yew_agent/oneshot/
provider.rs
