wip: suspense ergonomics

This commit is contained in:
Jonathan Kelley 2021-06-26 01:30:20 -04:00
parent bf21c82de0
commit 0f0fc3e4b8

View file

@ -8,9 +8,7 @@
//! and all work will stop. In this example, we store the future in a hook so we can always resume it.
use dioxus::prelude::*;
fn main() {}
#[derive(serde::Deserialize)]
struct DogApi {
message: String,
@ -18,9 +16,11 @@ struct DogApi {
const ENDPOINT: &str = "https://dog.ceo/api/breeds/image/random";
pub static App: FC<()> = |cx| {
let doggo = use_fetch(&cx, ENDPOINT, |cx, res: surf::Result<DogApi>| match res {
Ok(res) => rsx!(in cx, img { src: "{res.message}"}),
Err(_) => rsx!(in cx, p { "Failed to load doggo :("}),
let doggo = use_future_effect(&cx, move || async move {
match surf::get(ENDPOINT).recv_json::<DogApi>().await {
Ok(res) => rsx!(in cx, img { src: "{res.message}" }),
Err(_) => rsx!(in cx, div { "No doggos for you :(" }),
}
});
cx.render(rsx!(
@ -31,22 +31,29 @@ pub static App: FC<()> = |cx| {
))
};
use dioxus_core::virtual_dom::SuspendedContext;
use futures::Future;
use futures::FutureExt;
use std::pin::Pin;
fn use_fetch<'a, T: serde::de::DeserializeOwned + 'static>(
cx: &impl Scoped<'a>,
url: &str,
g: impl FnOnce(dioxus_core::virtual_dom::SuspendedContext, surf::Result<T>) -> VNode<'a> + 'a,
g: impl FnOnce(SuspendedContext, surf::Result<T>) -> VNode<'a> + 'a,
) -> VNode<'a> {
use futures::Future;
use futures::FutureExt;
use std::pin::Pin;
// essentially we're doing a "use_effect" but with no dependent props
let doggo_promise: &'a mut Pin<Box<dyn Future<Output = surf::Result<T>> + Send + 'static>> = cx
.use_hook(
move || surf::get(url).recv_json::<T>().boxed(),
// just pass the future through
|p| p,
|_| (),
);
cx.suspend(doggo_promise, g)
// essentially we're doing a "use_effect" but with no dependent props or post-render shenanigans
let fetch_promise = cx.use_hook(
move || surf::get(url).recv_json::<T>().boxed_local(),
// just pass the future through
|p| p,
|_| (),
);
cx.suspend(fetch_promise, g)
}
/// Spawns the future only when the inputs change
fn use_future_effect<'a, 'b, F: Future<Output = VNode<'b>>>(
cx: &impl Scoped<'a>,
g: impl FnOnce() -> F + 'a,
) -> VNode<'a> {
todo!()
}