Use subscription::run for download_progress example

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Héctor Ramón Jiménez 2022-01-15 11:45:19 +07:00
parent 35e4f30759
commit 75348c5b8c
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@ -1,112 +1,97 @@
use futures::Stream;
use iced_futures::futures;
use std::hash::{Hash, Hasher};
use iced_native::subscription;
use std::hash::Hash;
// Just a little utility function
pub fn file<I: 'static + Hash + Copy + Send, T: ToString>(
id: I,
url: T,
) -> iced::Subscription<(I, Progress)> {
iced::Subscription::from_recipe(Download {
id,
url: url.to_string(),
})
subscription::run(
Download {
id,
url: url.to_string(),
},
download,
)
}
#[derive(Debug, Hash, Clone)]
pub struct Download<I> {
id: I,
url: String,
}
// Make sure iced can use our download stream
impl<H, I, T> iced_native::subscription::Recipe<H, I> for Download<T>
where
T: 'static + Hash + Copy + Send,
H: Hasher,
{
type Output = (T, Progress);
fn download<I: Copy>(
download: Download<I>,
) -> impl Stream<Item = (I, Progress)> {
let id = download.id;
fn hash(&self, state: &mut H) {
struct Marker;
std::any::TypeId::of::<Marker>().hash(state);
futures::stream::unfold(
State::Ready(download.url),
move |state| async move {
match state {
State::Ready(url) => {
let response = reqwest::get(&url).await;
self.id.hash(state);
}
fn stream(
self: Box<Self>,
_input: futures::stream::BoxStream<'static, I>,
) -> futures::stream::BoxStream<'static, Self::Output> {
let id = self.id;
Box::pin(futures::stream::unfold(
State::Ready(self.url),
move |state| async move {
match state {
State::Ready(url) => {
let response = reqwest::get(&url).await;
match response {
Ok(response) => {
if let Some(total) = response.content_length() {
Some((
(id, Progress::Started),
State::Downloading {
response,
total,
downloaded: 0,
},
))
} else {
Some((
(id, Progress::Errored),
State::Finished,
))
}
}
Err(_) => {
match response {
Ok(response) => {
if let Some(total) = response.content_length() {
Some((
(id, Progress::Started),
State::Downloading {
response,
total,
downloaded: 0,
},
))
} else {
Some(((id, Progress::Errored), State::Finished))
}
}
}
State::Downloading {
mut response,
total,
downloaded,
} => match response.chunk().await {
Ok(Some(chunk)) => {
let downloaded = downloaded + chunk.len() as u64;
let percentage =
(downloaded as f32 / total as f32) * 100.0;
Some((
(id, Progress::Advanced(percentage)),
State::Downloading {
response,
total,
downloaded,
},
))
}
Ok(None) => {
Some(((id, Progress::Finished), State::Finished))
}
Err(_) => {
Some(((id, Progress::Errored), State::Finished))
}
},
State::Finished => {
// We do not let the stream die, as it would start a
// new download repeatedly if the user is not careful
// in case of errors.
let _: () = iced::futures::future::pending().await;
None
}
}
},
))
}
State::Downloading {
mut response,
total,
downloaded,
} => match response.chunk().await {
Ok(Some(chunk)) => {
let downloaded = downloaded + chunk.len() as u64;
let percentage =
(downloaded as f32 / total as f32) * 100.0;
Some((
(id, Progress::Advanced(percentage)),
State::Downloading {
response,
total,
downloaded,
},
))
}
Ok(None) => {
Some(((id, Progress::Finished), State::Finished))
}
Err(_) => Some(((id, Progress::Errored), State::Finished)),
},
State::Finished => {
// We do not let the stream die, as it would start a
// new download repeatedly if the user is not careful
// in case of errors.
let _: () = iced::futures::future::pending().await;
None
}
}
},
)
}
#[derive(Debug, Clone)]